EVS Shashi Chawla

A Textbook of
Environmental Studies
About the Author
Shashi Chawla is currently Assistant Professor in the Department of Applied
Sciences, Amity School of Engineering and Technology, New Delhi. He holds
MSc and MTech degrees from IIT Delhi and a PhD from Jamia Millia Islamia,
New Delhi, specialising in Chemistry, Polymer Science and Technology and
Nanocomposites. With a total of 14 years of teaching and research experience, he
has also worked in Lingaya’s Institute of Management and Technology, Faridabad,
as Lecturer, and in Jamia Millia Islamia as Visiting Faculty.
Dr Chawla has also worked on various R&D and consultancy projects for Inter
University Accelerator Centre and IIT Delhi. Dr Chawla’s research has included
various modern topics in science and technology like radiation graft modification
of polypropylene and development of PP based nanocomposites; swift-heavy-
ion-induced structural, conformational and chemical changes in BOPP film;
functionalisation of industrial polypropylene films via the swift-heavy-ion induced
grafting of glycidyl methacrylate; swift-heavy-ion-induced grafting of glycidyl
methacrylate onto latent ion tracks and surface of industrial polymeric films; and
grafting of glycidyl methacrylate onto industrial polyproylene films irradiated with
swift nickel ions.
He has presented many research and conceptual papers in various international
and national seminars and Conferences. Recently, he spoke on the Role of Chemistry
for Improvement in Quality of Water in the National Seminar on Role of Chemistry
for Improvement in Quality of Human Life, organised on 17-18th March 2012 by
Ujjain Engineering College, Ujjain (Madhya Pradesh).
He is a well-published author with books on Engineering Chemistry, Polymer
Science and Engineering, Essentials of Experimental Engineering Chemistry and
Materials Science and Engineering. Dr Chawla has been recognised as one of the top
100 educators of the world by the International Biographical Centre, Cambridge,
England, in 2009. His biographical profile is published in Marquis Who’s Who in
the World (2009).
With a keen interest in sports, he is the Sports Advisor for all the students of
ASET (1999–2012) and is a mentor in each academic session for the students of
ASET (2000–2012).
A Textbook of
Shashi Chawla
Assistant Professor
Department of Applied Sciences
Amity School of Engineering and Technology
New Delhi
Tata McGraw Hill Education Private Limited

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Dedicated to
My mother, Mrs Santosh Chawla,
for her support, enthusiasm, unfailing cooperation
and inspiration
Contents
1. Multidisciplinary Nature of Environmental Studies............................................... 1.1

2. Natural Resources.......................................................................................................... 2.1
3. Ecosystem ........................................................................................................................ 3.1
4. Biodiversity and Its Conservation.............................................................................. 4.1
5. Environmental Pollution and Its Effects................................................................... 5.1
6. Social Issues and the Environment ........................................................................... 6.1
7. Human Population and the Environment ................................................................. 7.1
8. Field Work......................................................................................................................... 8.1
Index
Preface
Environmental Science is an interdisciplinary academic field that integrates physical
and biological sciences (including physics, chemistry, biology, soil, science, geology
and geography) to the study of the environment, and the solution of environmental
problems. Environmental science provides an integrated, quantitative and
interdisciplinary approach to the study of environmental systems. Hence, preparing
a textbook on the Environmental Studies course, which is based on the latest syllabus
of UGC and also gives the reader sufficient information to understand the principles
and importance of the subject, has been an eye-opening experience.
A Textbook on Environmental Studies is a replete and concise content endowing the
essence of the theoretical concepts of the subject. It covers the course requirements
as per the UGC curriculum for all the undergraduate students of all disciplines. I
have made a sincere attempt to present the global subject of environmental studies
in the Indian context with ample examples, flowcharts, illustrations and cases from
India. I hope UG students of various Indian universities will find this book easy to
read, understand and implement.
Salient Features
This book is written in such a manner so as to
∑ Completely cover the entire syllabus of the ‘Environment Studies’ course of
various universities as per UGC framework
∑ Develop your understanding of this crucial and logical subject through
emphasis on fundamental principles, concepts and applications
∑ Promote visual and spontaneous learning through a simple and holistic
approach, full of learning objectives, memory aids, solved examples, well-
labelled illustrations, flowcharts and important definitions
∑ Enhance your knowledge with easy, concise and accurate Case Studies
incorporating most recent developments
∑ Enable you to perform confidently and effectively in various examinations
through its rich pedagogy for self-assessment, thought stimulation and skill
evaluation:
� 162 Theory Questions
� 26 Solved Examples
� 41 Case Studies
xii Preface
� 119 Fill in the Blanks

� 20 Match-ups
� 102 Multiple Choice Questions
� 85 True/False Questions
Chapter Organisation
The content is divided into eight comprehensive chapters.
Chapter 1 explains the multidisciplinary nature of environment studies. It outlines
the nature of our environment, environmental studies, need for public awareness,
environmental degradation, shelter security, economic security, social security,
effects of housing on environment and effects of industry on environment.
Chapter 2 discusses natural resources and includes topics like types of natural
resources, for example forest, water, mineral, food-security, energy and land
resources. It also discusses conservation of natural resources, sustainable lifestyles,
Sustainable Water Management (SWM) and the biogeochemical cycle.
Chapter 3 covers the ecosystem and explains ecological succession, food chain,
ecological pyramids and the types of ecosystems like forest ecosystem, aquatic
ecosystem, grassland ecosystem and desert ecosystem.
Chapter 4 presents biodiversity and its conservation. It gives details on values
or benefits of biodiversity, biogeographic zones of India, hot spots of biodiversity,
endangered and endemic species, rare and threatened species, threats to biodiversity,
human–wildlife conflicts and conservation of biodiversity.
Chapter 5 handles environment pollution and its effects and elucidates on
requirements of a nonpolluted environment, public health aspects, air pollution,
water pollution, land pollution or soil pollution, marine pollution, noise pollution,
thermal pollution, hazardous wastes, nuclear hazards (radiation pollution), solid
waste and its management, role of individuals in pollution prevention and disaster
management.
Chapter 6 is on social issues and the environment. This chapter discusses
sustainable development, urbanisation, water conservation, resettlement and
rehabilitation of people; its problems and concerns, wasteland reclamation, acts for
environmental protection, carbon credits, industrial symbiosis, initiatives and roles
of Nongovernmental Organisations (NGOs) in environmental protection, issues
involved in enforcement of environmental legislation and animal husbandry.
Chapter 7 discusses human population and the environment. It explains
population growth, family welfare programmes, environment and human health,
fundamental rights, human rights, value education, HIV/AIDS, environmental
education, women’s education, and role of information technology in environment
and human health.
Finally, Chapter 8 presents some fieldwork activities like visit to a local area to
document environmental assets: river/forest/grassland/mountain, visit to a local
polluted site: urban/ rural/industrial/agricultural; study of common plants, insects,
birds; and study of simple ecosystems: pond/river/hill slopes.
Preface xiii
All the chapters contain learning objectives, memory aids, solved examples, well-
labelled illustrations, flowcharts and important definitions.
Acknowledgements
I feel greatly indebted to my parents, Smt. Santosh Chawla and Shri Thakur Das
Chawla, who created in me an immense interest in this field. One of the main
sources of inspiration for writing this book has been the many interested students
in my classes. I am grateful to all the teachers, authors and environmentalists who
helped me enrich my knowledge of this subject.
I express my sincere gratitude to Dr Ashok K Chauhan, founder President, Amity
University; and Mr Atul Chauhan, President, RBEF and Amity University, for their
constant inspiration and encouragement.
I am thankful to Prof. B P Singh, Senior Director and Prof. Rekha Agarwal,
Director, Amity School of Engineering and Technology, for their continued
guidance and encouragement.
Along with this, a special note of appreciation goes to reputed faculty members
of various Indian universities who made suggestions, pointed out errors, responded
to my questions and helped in numerous other ways.
I deeply acknowledge the contribution of my wife, Mrs Taruna Chawla, and her
never-ending encouragement, moral support, patience and understanding. She has
done a commendable job of editing this manuscript.
A number of experts took pains to provide valuable feedback about the book. My
heartfelt gratitude goes out to those whose names are given below:
Sandeep Gupta A K Garg Engineering College, Ghaziabad, Uttar Pradesh
Shashi Bala Babu Banarasi Das National Institute of Technology and
Management, Lucknow, Uttar Pradesh
Manisha Shukla Babu Banarasi Das National Institute of Technology and
Management, Lucknow, Uttar Pradesh
Shibu Krishnan College of Engineering, Trivandrum, Kerala
Finally, I thank the publishing team of Tata McGraw-Hill for the enthusiasm
and interest shown by them during all the stages of the preparation of this book.
Feedback
I hope this book will serve its purpose and prove beneficial to its readers. Any
suggestions and constructive criticism towards further improvement of the book are
most welcome, all of which can be mailed to me at shashichawla10@rediffmail.com
SHASHI CHAWLA
1
MULTIDISCIPLINARY
NATURE OF
ENVIRONMENTAL
STUDIES
Learning Objectives
After studying this chapter, you should be able to
∑ describe the term environment and its segments
∑ explain the multidisciplinary nature of environmental studies
∑ discuss the scope and importance of environmental studies
∑ explain the need of public awareness for the protection of environment
∑ write short notes on shelter security, economic security and social security
∑ discuss the effects of housing and industry on environment
∑ explain why is environmental education provided to engineers
∑ enumerate the objectives and guiding principles of environmental education
1.1 ENVIRONMENT
The term ‘environment’ originated from the French word environner or environ
meaning ‘to surround’. From this etymology, environment means the things or
events that surround something else. In other words, environment means the
area in which something exists or lives.
Environment is defined as the social, cultural and physical conditions that surround,
affect and influence the survival, growth and development of people, animals or plants.
Environment includes everything around us. It encompasses both the living
(biotic) and nonliving (abiotic) components of the earth.
The environment consists of four segments. These are briefly discussed below:
Atmosphere It is the blanket of gases surrounding the earth.
Hydrosphere It is composed of various water bodies on the earth. It includes the
oceans, lakes, rivers, etc.
Lithosphere It contains various types of soils and rocks on earth.
Biosphere It is composed of all living organisms and their interactions with the
environment, viz. atmosphere, lithosphere and hydrosphere. The biosphere is the
earth’s zone of air, soil, and water that is capable of supporting life.
1.2 Environmental Studies
Environment
Atmosphere
Biosphere
Lithosphere Hydrosphere
Fig. 1.1 Concept of environment as a functional system composed

of organised, interacting and independent elements
1.1.1 Composition of the Lithosphere

The lithosphere (from the Greek ‘lithos’ for “rocky” and ‘sphaira’ for “sphere”) is the
rigid outermost shell of a rocky planet. The lithosphere includes the crust and the
uppermost mantle, which constitute the hard and rigid outer layer of the earth.
Fig. 1.2 Internal structure of the earth
There are two types of lithosphere.

(i) Oceanic Lithosphere It mainly consists of mafic crust and ultramafic mantle
(peridotite). It is associated with oceanic crust.
(ii) Continental Lithosphere It is associated with continental crust.
The oceanic lithosphere is more denser than the continental lithosphere.
Multidisciplinary Nature of Environmental Studies 1.3
1.1.2 The Biosphere

The biosphere is the earth’s zone of air, soil, and water that is capable of supporting
life. It is a zone which reaches about 10 km into the atmosphere and down to the
deepest ocean floor. Processes in the biosphere include life and death, and evolution
and extinction. Within the biosphere, the basic unit of analysis or study is the
ecosystem. Thus, the biosphere is the global sum of all ecosystems.
The atmosphere forms a protective
osphere
shell over the earth. The troposphere is Strat
the lowest layer and is only 12 km thick.
oposphere
It is the only part warm enough for us Tr
to survive in. 12 km
Earth
The stratosphere is 50 km thick and
contains a layer of sulphates which is km
important for the formation of rain. It 50
also contains a layer of ozone, which

absorbs ultraviolet light known to cause
cancer.
Fig. 1.3 Atmosphere around the earth
1.1.3 Components of the Environment

Physical, biological and cultural environments are the three distinct dimensions
of the environment. The study of cultural environment (i.e. social environment,
economic environment and political environment) has been allocated to
sociologists, economists and managers. Biologists and doctors are in charge of
studying our biological environment [which comprises plants (flora), animals (fauna)
and microorganisms]. Environmentalists take care of the physical environment
(lithosphere, hydrosphere, atmosphere).
Cultural Environment
∑ Social
∑ Economic
∑ Political
Environemnt
Biological Environment Physical Environment

∑ Flora ∑ Atmosphere
∑ Fauna ∑ Lithosphere
∑ Microorganisms ∑ Hydrosphere
Fig. 1.4 Various types of environments and interactions

between their various elements
The components of the environment are classified in terms of biotic and abiotic
components based upon living components and nonliving components respectively.
It is from this component system that the study of the structure of ecosystems was
evolved.
Fig. 1. 5 Components of the environment
1.1.4 Relationship between Humans and Environment
� Carbon dioxide for plants, air pollutants � Food/shelter/timber

� Oxygen for life, combustion of fossil fuels � Water pollutants/waste
� Fertilizer/soil pollutants, industrial waste � Water, fishes, sea-food
Fig. 1.6 Human–environment relationship: (A) Urban growth (B) Industrial expansion
With the development of human society, the human–environment relationship

is changing. These relationships from prehistoric to modern periods is summarised
below in four stages.
(A) Stage I: Period of Hunting and Food Gathering
In this period, the basic requirements of primitive humans were limited to food
and shelter. There was a very friendly relationship between humans and their
environment because of limited requirements, very low population and disorganised
society. However, the discovery of fire and invention of tools and weapons made
humans capable of exploiting natural resources. Due to their carelessness while
cooking, destruction of the environment started with inadvertent burning of forests.
Sometimes, humans intentionally used fire to clear the forest for creating habitats
and to drive away dangerous animals from his surroundings.
(B) Stage II: Period of Animal Domestication and Pastoralism
In this period, humans learnt to domesticate animals for milk, meat, etc. They also
started living a community life. This ultimately led to the destruction of forests and
exploitation of environmental resources. However, the changes brought about by
human activities in the environment were well within the limits of selfregulatory
mechanisms of the environment.
(C) Stage III: Period of Plant Domestication and Agriculture
The emergence of socially organised human communities, human civilisations
(specially, river-valley civilisations), farming practices (specially domestication of
plants and primitive type of agriculture), gradual increase of human population and
domestic animals led to the spread of human population and destruction of natural
ecosystems. However, the human race continued to be guided by the physical
environment and no serious damage was done to the natural environment.
(D) Stage IV: Period of Science, Technology and Industrialisation
In this period, humans started exploiting natural resources in a reckless and
indiscriminate manner for urban growth and industrial expansion. In this period, the
hostile relationship between humans and their natural environmental was initiated.
This has created most of the present ecological and environmental problems.
1.1.5 Impact of Technology and Development on Environment

Technology and development help us
(i) to provide better transport and delivery,
(ii) to speed up production and manufacture of goods,
(iii) to do efficient farming for making food, and
(iv) to make faster and reliable communication, etc.
Due to technology advancements, trade and commerce flourished at faster rates
and brought about globalisation. As trade and commerce grew, it increased the
greed of humans which resulted in direct and indirect impact on the environment.
These are briefly discussed below:
(i) Direct Impacts These impacts are pre-planned. Both positive and negative
consequences of any programme (launched to change or modify the natural
environment for development of the concerned region) are known in advance.
Suppose deforestation is done either for cropland or for commercial purposes. It
leads to accelerated rate of soil erosion, resulting in loss of soil fertility and floods.
However, these effects can be stopped by afforestation of the deforested area. Thus,
direct impacts are reversible.
(ii) Indirect Impacts The indirect impacts of humans on the environment are
mainly due to industrial development. These indirect impacts are not immediately
noticeable but are experienced after long time. Sometimes, such effects are not
reversible. They change the overall natural system and the resultant chain effects
sometimes become suicidal for humans. Majority of the indirect impacts on the
environment are related to pollution and environmental degradation.
Fig. 1.7 Impact of technology and development on environment
Green Technology for Lessening the Accumulated Negative Impacts

Green technology is helping us in the following ways:
(i) It provides better solutions of generating heat and energy.
(ii) The sun’s powerful UV rays are being harnessed through solar panels.
(iii) The kinetic powers of wind and water currents are being utilised to produce
electricity.
These and some other green technological approaches help in lessening the
demand for coal and fossil fuels, whose burning contributes to air pollution and
consequent respiratory diseases and fatal illnesses.
1.2 ENVIRONMENTAL STUDIES

Environmental education refers to organised efforts to teach how natural
environment functions and, particularly, how human beings can manage their
behaviour and ecosystems in order to live sustainably.
Environmental study is the academic field which systematically studies every issue
that affects an organism.
Environmental science is the systematic study of the scientific principles, economic
influences and political action, and inter-relationship among living organisms
(biotic components) and nonliving things (abiotic components) which affect the
environment.
Fig. 1.8 Major aspects of environmental science

Both theoretical and applied aspects of human impact on the world are studied
in environmental science.
The theoretical aspects of environmental science identify threats to our survival and
our future generations. For example, how ozone-layer depletion injures plant and
marine life and even reduces our immunity to diseases is studied in theoretical aspects.
The applied aspects of environmental science suggest solutions to the identified
environmental problems.
1.2.1 Multidisciplinary Nature of Environmental Studies

The environment is everybody’s concern as we all live on the same planet. An
understanding of the working of the environment requires the knowledge of various
fields.
Air pollution is one of the important topics in environmental studies. Table 1.1
shows a list of topics commonly studied in air pollution and the related traditional
fields of knowledge illustrating the interdisciplinary nature of the subject.
Table 1.1 Interdisciplinary nature of environmental studies—air pollution

Environmental issue Knowledge of subject required
(i) History of air pollution and air pollu- (i) History
tion accidents
(ii) Economic impacts of air pollution (ii) Economics, demography
(iii) Nature and reactions of air pollutants (iii) Chemistry and chemical engineering
(iv) Air-pollution control devices (iv) Physics, chemistry and various
branches of engineering
(v) Effects of air pollutants on human be- (v) Zoology, botany, physics, chemistry
ings, animals, plants and materials
(vi) Sociological impacts of air pollution (vi) Sociology
(vii) Conservation of resources and pollu- (vii) Various branches of physical and
tion control political sciences
(viii) Alternative fuels (viii) Various branches of physical sciences
(ix) Ozone hole and global warming (ix) Pure as well as social sciences
(x) Effect of climate on air pollution (x) Mathematical modelling, meteorology,
thermodynamics, geography, etc.
Ag
ric
ult
ur
e
Fig. 1.9 Many disciplines contribute to environmental science

The situation is similar in other topics of environmental studies.

To sum up, environmental science incorporates the principles of pure sciences
(like physics, chemistry, biology, earth science, agriculture, engineering, computer
science, etc.) with input from the social sciences (such as political science, law,
philosophy, sociology and economics), thus creating a new interdisciplinary field.
It is essentially a multidisciplinary approach that brings about an appreciation of
our natural world and human impacts on its integrity.
1.2.2 Scope of Environmental Studies

The scope of environmental studies is so wide that it is related to every science and
scientific aspects in general and biology in particular.
The scope of environmental studies in numerous fields is given below:
(i) Conservation and management of natural resources (like forest resources, water
resources, etc.)
(ii) Conservation of biodiversities (like conservation of genetic diversity, species
diversity, ecosystem diversity, landscape diversity, etc.)
(iii) Control of environmental pollutions (like air pollution, water pollution, soil
pollution, solid waste pollution, noise pollution, electronic waste pollution,
e-pollution, etc.)
(iv) Control of human population
(v) Replacement of development (like green revolution, urbanisation,) economic
growth, (industrialisation, etc.) with sustainable development
Fig. 1.10 Scope of environmental studies
1.2.3 Objectives of Environmental Studies

The objective of environmental studies is to help social groups and individuals
acquire an awareness of the environment as a whole and its related problems. They
should
(i) acquire the skills for identifying and solving environmental problems
(ii) participate in improvement and protection of the environment
(iii) develop the ability to evaluate measures for the improvement and protection
of environment
(iv) acquire an attitude of concern for the environment

(v) gain a variety of experiences and acquire a basic understanding and knowledge
about the environment and its allied problems.
To sum up, the objective of environmental studies is to develop a world in
which persons are aware of and concerned about the environment and the problems
associated with it, and committed to work individually as well as collectively towards
solutions of current problems and prevention of future problems.
1.2.4 Guiding Principles of Environmental Studies

The guiding principles of environmental education are as follows:
(i) Environmental education should help learners discover the symptoms and
real causes of environmental problems.
(ii) Environmental education should have an interdisciplinary approach, and
it should be continuous and compulsory, right from the pre-school to all
formal as well as nonformal higher levels.
(iii) Environmental education should encourage stewardship to help reduce
human impact on the planet.
(iv) Environmental education should emphasise the importance of economic
development without degrading the environment (i.e. sustainable develop-
ment).
(v) Environmental education should enable policymakers to include
environmental-impact analysis in proposed developmental projects in order
to minimise environmental damages.
(vi) Environmental education should emphasise the necessity of seeking
international cooperation in environmental planning, and prevention and
control of environmental problems.
(vii) Environmental education should lay more stress on practical training and
practical activities.
(viii) Environmental education should promote the value and necessity to
examine major environmental issues from the local, national, regional, and
international point of view.
(ix) Environmental education should emphasise the complexity of environmental
problems and the need to develop critical thinking and problem-solving
skills.
1.2.5 Importance of Environmental Studies

For the survival of the present and future generations, environmental education is
necessary.
The important benefits of environmental studies are the following:
(i) It directs attention towards the unlimited exploitation of environment (nature)
by humans for greed or for the sake of development. Exploitation of nature has
threatened the survival of all living organisms, including humans.
(ii) It generates concern for the changing environment, population explosion
and throws light on the methods of solution.
Fig. 1.11 A self-perpetuating vicious cycle of poverty, environmental

degradation and population growth
(iii) It helps to understand different food chains and to find ways and means to
maintain ecological balance.
(iv) It helps in the maintenance of healthy life. Through improved health of
people, economic productivity gets increased.
(v) It imparts knowledge about conservation of energy and reducing material
dependence
(a) by refusing to purchase things which are harming our environment
(b) by reusing a product number of times
(c) by motivating recycling of recyclable products
(vi) It helps in developing social responsibility towards protection of environment
and control of environmental pollution.
(vii) It helps in appreciating and enjoying nature and working towards sustainable
development.
Fig. 1.12 Population stabilisation, poverty alleviation and environmental

protection are mutually supportive of and dependent on one another
1.2.6 Why is Environmental Education Provided to Engineers?

Engineering graduates entering industry get benefitted from environmental
competence in their practice fields. This is because planning, extraction, design
and manufacturing, all have some common and some unique regulations for their
environmental effects.
Engineers are capable of finding creative solutions for climate change and other
environmental problems. They will play a crucial role in helping the human race
coexist with the rest of the world in decades to come. This is because, engineers use
principles of chemistry and biology to prevent or solve environmental problems.
They work in many areas, including industrial hygiene, land management, air-
pollution control, toxic-materials control, etc. The duties of an environmental
engineer range from planning and designing an effective waste-treatment plant, to
study the effects of pollution on humans. A sales engineer in the environmental
engineering field may be responsible for the sale of air pollution control products to
factories. In addition to sale, they often assist with the design and modification of
their products based on customer feedback.
1.3 NEED FOR PUBLIC AWARENESS

Humans are responsible for depletion
of natural resources; degradation of the
vital life-supporting systems (like air,
water, soil, etc.); ecological imbalance;
deteriorated environment, etc. Solid-
waste disposal, oil pollution, water
pollution, air pollution, Itai-Itai disease,
Minamata disease, Chernobyl disaster,
Bhopal gas tragedy, smog, etc., are some
of the examples which are threatening Fig. 1.13 Need for awareness of
human survival. environment in public
To get rid of these problems, environmental awareness is necessary. It ensures
that everyone knows about the consequences of his/her activities on nature.
To protect global environment for sustainable development, we should do the
following:
(i) Preserve Forest Cover Humans should minimise cutting of trees and using
timber for aesthetic pleasure such as decoration of drawing rooms.
(ii) Preserve Natural Resources Humans should not unnecessarily and exhaus-
tively extract natural resources such as mineral resources, water resources, etc.
(iii) Conserve Energy Humans should not harness too much energy from burn-
ing of fossil fuels.
(iv) Maintain Ecological Balance Humans should work to create synergy
between green revolution and industrial evolution by compulsory growing
green belts around industrial areas, maintaining wildlife sanctuaries and
national parks.
(v) Practice Green Technology: Everyone from a farmer in the village to a policy
planner in the government should use green technology that incorporates
(a) treatment of air emissions,
(b) treatment of waste waters,
(c) waste reduction, waste or emission management, and
(d) use of nonconventional, renewable energy resources like solar energy on
priority, etc.
1.4 ENVIRONMENTAL DEGRADATION

The ability of an environment to sustain the resource demands of a species or a
community without losing its ability to regenerate the resource is termed the
carrying capacity.
Environmental degradation means that the carrying capacity is reduced by some
natural or human phenomenon.
Environmental degradation is the deterioration of the environment through
extinction of wildlife, depletion of natural resources and the destruction of
ecosystems.
The main causes of environmental degradation are the following:
(i) Population (P) More population means less resource availability per person,
which encourages couples to have more children to help gather resources leading to
resource exploitation and environmental degradation.
(ii) Affluence (A) Rich people overuse the resources, and this lead to air, water,
land and environmental pollution. Poor people exploit natural resources and so they
also cause environmental degradation.
(iii) Technology (T) Heavy industrialisation, unplanned and heavy consumption
of natural resources in which even renewable resources are not given time for renewal
also lead to environmental degradation.
To sum up, environmental degradation (ED) is a function of P, A and T.
ED = f (P ¥ A ¥ T )
The causes and effects of environmental pollution are illustrated in Fig. 1.14.
1.5 SHELTER SECURITY

All of us need shelter security for food, water, sleep and warmth.
When humans feel safe and secure in their homes, and have the love and support
of family and friends, they have the opportunity to grow in confidence, to gain the
respect of others, and most importantly to achieve a high level of self-respect.
1.5.1 Problems Faced by Homeless People

If people do not have shelter security, they may have difficulty finding a school or a
job, they may lose touch with family and friends, they may feel excluded, they may
be unsafe, and they have reduced access to health care.
Fig. 1.14 Causes and effects of environmental degradation
1.5.2 Causes of Homelessness

People become homeless for the following reasons:
(i) Unemployment
(ii) Lack of money to buy a property or to pay rent
(iii) Family breakdown due to domestic violence
(iv) Natural disaster or war
(v) Drug or alcohol addiction
(vi) Increased wealth disparity and income inequality leading to distortions in
the prices of houses
(vii) Mortgage foreclosures on homes by banks
1.6 ECONOMIC SECURITY

Economic security refers to the condition of having a stable income (or other
resources) to support a standard of living now and in the foreseeable future. It
includes the society’s production levels and monetary support for nonworking
citizens.
When children, adults, and families are safe, healthy, educated and have sufficient
money for comfortable living, it means they are economically secure.
International relations between countries are mainly governed by their economic
securities.
If a foreign government gets unauthorised access to proprietary information or
technology then the country’s overall economic security is under threat.
Economic security of children and their parents is indicated by the income level
and employment security of their families.
Economic security of retired people is based on social-security benefits, pensions,
savings, earnings and employment, and health-insurance coverage.
Economic security can be defined as the condition of an individual, household or
community to be able to cover the essential needs (like food, shelter, access to health care,
education, etc.) and unavoidable expenditures in a sustainable manner.
If essential needs are not covered, a situation of crisis develops. The crisis can be
of the following four types:
Essential needs are still covered, but are at risk of no longer being addressed in
pre-crisis. Some essential needs are no longer covered in acute-crisis. Essential needs
are insufficiently covered in chronic-crisis. Essential needs are covered by structure
whose sustainability remains fragile in post-crisis.
The aim is to save lives in pre-crisis and acute-crisis. The aim is to support
livelihoods in chronic-crisis and post-crisis.
1.7 SOCIAL SECURITY

Social security means providing social welfare services to the poor, aged, disabled,
widowed, retired, children or unemployed people by the society.
(A) Negative Effects of Social Security Social security may discourage
people from working and saving to reduce international competitiveness and em-
ployment creation. It may also encourage people to take early retirement.
(B) Positive Economic Effects of Social Security

(i) It may help maintain effective demand at the national level.
(ii) It may help create conditions in which a market economy can flourish, by
encouraging workers to accept innovation and change.
1.8 EFFECTS OF HOUSING ON ENVIRONMENT

Traditionally, home is considered a haven, where humans are protected and nurtured.
However, a house can also be a health hazard when factors such as poor design, envi-
ronmental contamination and poverty combine to cause or exacerbate disease.
1.8.1 Housing and Health
Housing is an environmental health issue because of various socio-economic
conditions as illustrated below:
(i) Lead-based paints were used for renovation and painting homes. They are
major causes of childhood lead poisoning.
(ii) Poorly constructed houses lead to stress and children stay inside with
increasing exposure to pollutants resulting in childhood asthma.
(iii) Substandard housing contributes to asthma incidences.
Fig. 1.15 Housing as an environmental health issue
1.8.2 Housing and Environment

The quality of environment is determined by the following factors:
(i) Maintenance and arrangement of houses.
(ii) The presence, quality and accessibility of facilities
(iii) Security
(iv) Street cleanliness in the residential area, etc.
The material flows for houses during construction, maintenance and operation
phases are illustrated below:
Fig. 1.16 Material flows for houses

1.8.3 Strategies for Improvement of Environment

(i) Reduce the natural resource depletion regarding material use.
(ii) Reduce global warming via efficient energy and material use.
(iii) Reduce air, noise and water pollution by eco-designing of houses.
(iv) Reduce the environmental impact of housing through innovations in design,
like green housing, zero emission housing, etc.
1.9 EFFECTS OF INDUSTRY ON ENVIRONMENT

For the development of a country and the prosperity of its people, industry is
essential. Unfortunately, our technology choices have turned out to be wasteful
because decisions are based on short-term and narrow goals of the enterprise rather
than a holistic view of the full range of consequences from the use of a technology.
1.9.1 Adverse Environmental Effects of Industry

The total global flow of materials is around 500 billion tons a year. Only 6%
actually ends up in consumer products whereas much of the virgin materials are
being returned to the environment in the form of harmful solid, liquid, and gaseous
wastes. Some of the adverse effects of industrial practices are summarised below:
(i) Industrial practices release enormous quantities of air and water pollutants.
(ii) They generate huge amounts of hazardous wastes.
(iii) Industrial effluents have polluted many lakes, rivers and coastal environments.
(iv) Industrial accidents, such as the Bhopal gas tragedy, often have tragic
environmental consequences.
1.9.2 Approaches for Minimising Harmful Effects of Industry on

Environment
The approaches for minimising adverse effects of industrial practices on environment
are outlined below:
(i) Pollution Prevention Try to create less of the pollutant or waste or eliminate
it.
(ii) Recycling and Reuse They not only reduce pollution, but they also conserve
natural resources.
(iii) Treatment It is used to reduce the volume or toxicity of the waste.
(iv) Disposal Responsible disposal as per the law by both industries and
municipalities should be done.
Important Definitions
∑ Environment is defined as the social, cultural and physical conditions that surround,
affect and influence the survival, growth and development of people, animals or
plants.
∑ The biosphere is the earth’s zone of air, soil, and water that is capable of supporting
life.
∑ The objective of environmental studies is to develop a world in which persons are
aware of and concerned about the environment and the problems associated with
it, and committed to work individually as well as collectively towards solutions of
current problems and prevention of future problems.
∑ The ability of an environment to sustain the resource demands of a species or a
community without losing its ability to regenerate the resource is termed the carrying
capacity.
∑ Environmental degradation means that the carrying capacity is reduced by some
natural or human phenomenon.
∑ All of us need shelter security for food, water, sleep and warmth.
∑ Economic security can be defined as the condition of an individual, household or
community to be able to cover the essential needs (like food, shelter, access to health
care, education, etc.) and unavoidable expenditures in a sustainable manner.
∑ Social security means providing social welfare services to the poor, aged, disabled,
widowed, retired, children or unemployed people by the society.
EXERCISES
1. Define environment. (b) Discuss the physical components of
2. Briefly discuss four major global en- the environment.
vironmental problems. 8. What are the objectives and guiding
3. What is the importance of environ- principles of environmental education?
mental studies? 9. Why is environmental education
4. Discuss how formal environmental provided to engineers?
education can help in managing the en- 10. What is the meaning of environ-
vironment. ment? Discuss the relationship be-
5. (a) Write a note on the importance tween different components/parts of
of education on environmental issues environment.
and concerns. 11. Discuss the relationship between
(b) Describe the multidisciplinary na- humans and environment. Why is en-
ture of environmental studies. vironmental protection discussed re-
6. (a) Explain the impact of technology cently?
and development on environment. 12. What is meant by society and en-
(b) Give the composition of atmosphere vironment? How these are related to
and lithosphere. each other?
7. (a) What are the components of 13. Explain the need for public aware-
environments? Explain by drawing a ness about the environment and its
sketch. degradation.
OBJECTIVE TYPE QUESTIONS

I. Fill in the Blanks B.
1. The study of reciprocal relationship Column I Column II
between organisms and environment is
called ______ . 1. Industrial revolu- (a) 17th and 18th
2. ______ teaches us how to respect tion (Father) centuries
nature. 2. Global warming (b) James Watt
3. The term environment has been de- 3. Environmental (c) CO2
rived from the French word ‘environner’ movement
which means ______ .
4. Industrial revolu- (d) Rachael
4. World Environment Day is celebrat-
tion took place in carron
ed on ______ .
5. The term ecology was introduced by 5. Industrial revolu- (e) England
______ . tion took place dur-
6. The United Nations Conference on ing
Environment and Development (Earth III. Multiple Choice Questions
Summit) was held at ______ in ______ . 1. The part of the earth and its atmo-
7. The world’s first Intergovernmental sphere in which organisms live is the
Conference on Environmental Educa- (a) biosphere (b) biomass
tion was held in ______ . (c) biota (d) biome
8. ______ is often identified as the 2. Which of the following conceptual
founder of ecology. sphere of the environment has the least
9. The part of the earth and its storage capacity of matter?
atmosphere in which organisms live is (a) Lithosphere (b) Atmosphere
known as ______ . (c) Biosphere (d) Hydrosphere
10. Troposphere is located ______ 3. Which one of the following is an
stratosphere. abiotic component of the ecosystem?
11. World Food Day is recalled on (a) Plants (b) Fungi
______ . (c) Humus (d) Bacteria
II. Match the following terms. 4. The most stable ecosystem is
Match the terms of column I with (a) mountain (b) desert
appropriate terms of column II. (c) forest (d) ocean
A. 5. Increase in fauna and decrease in
flora would be harmful due to increase
Column I Column II
in
1. Living organism (a) Stratosphere (a) CO2 (b) O2
2. Air (b) Biosphere (c) N2 (d) SO2
3. Water (c) Atmosphere 6. The largest reservoir of nitrogen in
our planet is the
4. Soil (d) Hydrosphere (a) fossil fuel (b) atmosphere
5. Ozone (e) Lithosphere (c) biosphere (d) ocean
IV. Indicate True or False for the 3. Public awareness is a must for the
following statements: protection of environment. True/False
1. Biosphere is made of atmosphere, 4. Temperature in thermosphere can
hydrosphere and lithosphere. be as high as 1200°C. True/False
True/False 5. The term ecology is not derived
2. Environmental studies is multidisci- from the Greek word ‘Oekologie’.
plinary in nature. True/False True/False
Answers to Objective Type Questions

I. Fill in the Blanks II. Matching the terms.
1. Ecology A. 1. (b) 2. (c) 3. (d) 4. (e) 5. (a)
2. Environmental studies B. 1. (b) 2. (c) 3. (d) 4. (e) 5. (a)
3. To encircle or surround
4. 5th June III. Multiple Choice Questions
5. Ernst Haeckel 1. (a) 2. (b) 3. (c) 4. (d)
6. Rio de Janerio, 1992 5. (a) 6. (b)
7. Tbilisi, Georgia IV. True or False
8. Eugen Warming 1. True 2. True 3. True 4.True
9. Biosphere 5. False
10. Below
11. October 16th
2
NATURAL
RESOURCES
Learning Objectives
∑ explain the difference between renewable, nonrenewable and perpetual
natural resources
∑ describe the impacts of over-utilisation of underground and surface water
∑ identify and explain the core causes of water crisis in the world
∑ explain the fluoride problem in drinking water
∑ discuss the measures to conserve water
∑ explain the various natural mechanisms involved in the self-purification of
rivers
∑ describe the effects of mineral extraction on the environment
∑ explain the necessity of conserving mineral resources
∑ describe mineral resources of India
∑ define deforestation
∑ explain causes and ill effects of deforestation
∑ describe measures taken for conserving forest wealth
∑ name and explain various steps involved in the carbon cycle, nitrogen cycle,
and sulphur cycle
∑ explain how elemental carbon is recycled in nature
∑ explain the various energy resources
∑ describe the energy scenario in the Indian context
∑ compare the alternative energy resources
∑ explain the nonrenewable energy resources
∑ describe the hydropower energy as renewable, clean and nonpolluting
source of energy
∑ explain fossil fuels
∑ describe nuclear energy
∑ enumerate the application of solar energy in modern days
∑ explain the use of solar energy for space heating of buildings
∑ describe hydrogen as an alternative future source of energy
∑ explain the biomass energy as renewable energy
∑ describe a fuel cell
∑ explain the various ways in which energy from the ocean can be obtained
∑ discuss merits and limitations of geothermal energy
2.1 INTRODUCTION
Resources are objects, materials, creatures, or any form of energy found in nature that
can be used to perform any useful function. They are or may become of potential
economic interest due to their inherent properties.
Reserves are that part of a resource which has been fully evaluated and is found
commercially viable to work on the consideration of mining, metallurgical,
economic, marketing, legal, environmental, social and governmental factors.
Fig. 2.1 Reserves and resources
2.2 TYPES OF NATURAL RESOURCES

Based on their use, availability, origin and economic status, natural resources can be
classified into the following types:
2.2.1 Perpetual, Renewable and Nonrenewable

Natural Resources
Based on their availability or how human activities affect them, natural resources are
of the following three types:
(A) Perpetual Resources Perpetual resources are those natural resources that
naturally perpetuate themselves and are not affected by human use.
Examples Sunlight, wind, rainfall water and tides.
(B) Renewable Resources Renewable resources are those natural resources
that have the inherent ability to renew or replenish themselves if given a reasonable
amount of time.
Examples Soil, fresh water, forest, etc.
(C) Nonrenewable (or Exhaustible) Resources Nonrenewable resources
are those natural resources that cannot be regenerated or renewed or replaced within
a time framework.
Examples Fossil fuels (such as coal, petroleum, natural gas, etc.), nuclear power.
Natural Resources 2.3
Table 2.1 Differences between perpetual, renewable and nonrenewable resources

Perpetual Resources Renewable Resources Nonrenewable Resources
(i) They are replenished natu- (i) The environment has (i) They are being consumed
rally at a rate faster than the capacity to replenish or used up faster than they
their rate of consump- them as long as they are can be made by nature.
tion. properly conserved.
(ii) They last forever regardless (ii) Human activities can (ii) Once these resources are
of anything humans do to affect the supplies of reused up, they are gone
them. newable resources. forever.
(iii) Examples: Wind, sunlight (iii) Examples: Soil, forest (iii) Examples: Coal, petroleum
(D) Intangible Resources Intangible resources are those natural resources that
are available in huge quantities, but at the same time can be destroyed easily.
The tourism industry is based on serenity, beauty, diversity, open space and
satisfaction. However, a small piece of trash can easily destroy the beauty of any
place. Thus, intangible resources are both exhaustible and inexhaustible.
2.2.2 Biotic and Abiotic Natural Resources

Based on their origin, natural resources are of the following two types:
(A) Biotic Resources Biotic resources have originated from some living or-
ganism or have life.
Examples
∑ Renewable: Livestock, fisheries, flora, fauna and humans.
∑ Nonrenewable: Coal, petroleum, etc.
(B) Abiotic Resources Abiotic resources are of nonliving origin.
Examples Minerals, rocks, water, etc.
2.3 FOREST RESOURCES

(A) Types of Forest Resources
Forests are broadly classified into there categories from the point of view of use as
a resource:
(i) Old-Growth or Ancient Forests These are uncut forests that have not been
seriously disturbed by natural disasters or human activities. As a result, they have
attained great age, and thereby exhibit unique ecological features.
(ii) Second-Growth Forests They result from secondary ecological succession
that takes place when forests are cleared and then left undisturbed for long periods
of time.
(iii) Plantations These are (large, artificially established) forests of commercially
valuable trees. These are created mostly by clearing old-growth or second-growth
forests.
Table 2.2 Differentiation characteristics of forests

Forest-Resource Type Canopy Layer Biodiversity Prone to Disease
(i) Old-growth Several More Less
(ii) Second-growth One Less More
(iii) Plantations One Least Maximum
example 1 Automated analysis of forest satellite imagery is not reliable

for estimating forest cover. Comment with respect to Indian perspective.
Solution The Forest Survey of India (FSI) reported in 2009 that Indian forests
had grown by almost 5% per year from the 1990s. They used automated analysis of
forest satellite imagery.
The above method cannot differentiate between native forests and exotic tree
plantations (such as rubber, teak, pine, eucalyptus trees). The plantation forest
covers have very limited value for biodiversity.
Monoculture plantations are expanding by nearly 6,000 to 18,000 square
kilometres per year in India.
If one subtracts plantations from total forest cover then India’s native forests
have actually declined at an alarming pace, from 0.8% to 3.5% per year from 2000–
2005.
(B) Functions of a Forest Forests help in production of timber, regulation of

stream flow, control of erosion, recreation, provision of wildlife habitat, etc.
2.3.1 Use and Over-exploitation of Forest Resources

Beneficial functions of forests are the following:
(i) Influence on Climate The crowns of the trees hold the moisture in because
the force of the wind is broken. It makes the forest cool in the summer and warm
in the winter.
(ii) Control of Run-off Leaves and branches of trees break the impact of rain,
causing it to drip rather than have a strong force. Rain is absorbed by the
ground, reducing surface run-off.
(iii) Flood Control Forested watersheds help in avoiding extremes of water
flow and so help in flood prevention.
(iv) Wildlife Habitat Provision Wildlife uses the products of trees and forests
as food and shelter respectively.
(v) Prevention of Soil Erosion Water moves slowly through forested soils
and stays free of sediments.
(vi) Reduction of Wind Erosion Trees are used as windbreaks and slow down
the force of wind.
(vii) Removal of Pollutants The roots of trees absorb soil and water pollutants.
Sulphur dioxide is used for metabolism of trees. Thus, forests aid in the
cleansing of air, water and soil.
(viii) Noise Abatement Trees act as a sound barrier.

(ix) Recycling of Nutrients
Forests help in nutrient
recycling.
(x) Provisions for Healthy
Survival of Local Com-
munities and Man-
kind Forests provide
employment and income,
aesthetic pleasure and
spiritual solace. They also
provide food, fibre, hon-
ey, medicinal plants and Fig. 2.2 Environmental and commercial
minerals. value of forests
2.3.2 Deforestation
Deforestation involves the cutting down, burning, and damaging of forests.
Deforestation can be defined as the change of forest with depletion of tree crown
cover of more than 90%. However, depletion of forest-tree-crown cover less than
90% is considered as forest degradation.
(A) Causes of Deforestation The main causes of deforestation are sum-
marised below:
(i) Population explosion
(ii) Agriculture: shifting cultivation, overgrazing, cash-crop economy, etc.
(iii) Commercial logging: cutting trees for sale as timber or pulp
(iv) Poverty
(v) Mining
(vi) Dams
(vii) Infrastructure creation for logging
(viii) Forest fires
(ix) Acid rain
(x) Development projects and housing projects.
(B) Ill Effects of Deforestation The ill effects of deforestation are sum-
marised below:
(i) Soil Erosion Soil is exposed to wind, sunlight, evaporation due to
deforestation. Soil fertility goes down due to soil erosion and rapid leaching
of essential mineral nutrients.
(ii) Harm to Fisheries As the soil is eroded, it accelerates siltation in dams,
rivers, and the coastal zone. The increased sedimentation harms downstream
fisheries.
(iii) More Floods and Droughts Because of deforestation, there is no regulation
of the flow into rivers. As a result, floods and droughts alternate in the
affected areas.
(iv) Habitat Loss of Wildlife Butterflies, migratory birds and wild animals
suffer due to the loss of their habitat.
(v) Extinction of Some Species Many species are affected and some become
extinct.
(vi) Local and Global Climate Changes The rainfall pattern is affected as
the forest is cut down. Local and global climate changes may result from
deforestation.
(vii) Global Warming If the trees are burned, the carbon is released immediately
as carbon dioxide which lead to global warming.
(viii) Danger for the Survival of Local Communities Communities lose their
source of food, fuel, construction materials and areas for livestock grazing by
deforestation.
Fig. 2.3 Effects of deforestation
(C) Causes of Deforestation in India The deforestation in India is rooted

in the commercially oriented forest use and ownership policies of the British gov-
ernment which continued even after India gained independence. (The other cause
was the expansion of agriculture.) Immediately after independence, the other major
causes of deforestation were
(i) State-sponsored agricultural expansion
(ii) Rapid industrialisation
(iii) Urbanisation
(iv) Growing consumerism
(v) Policies and programmes of unsustainable development like subsidies offered
for making the paper and plywood industry a viable and profitable venture
(vi) Lack of education and awareness programmes regarding (a) real cost of the
destruction of forests, and (b) legal provisions for the safeguarding of the
forests
(vii) Absence of strict implementation of laws
(viii) Not including people at all levels in planning, decision making and
implementation (i.e. absence of social engineering)
(ix) Not taking the correct decisions by decision makers on the basis of accurate
knowledge and information
(x) The campaign to safeguard forests is not accompanied with social, economic
and political reforms
(xi) Corruption of government institutions
(xii) Population growth and overpopulation
(xiii) The inequitable distribution of wealth and power
(xiv) Other causes: shifting cultivation, dams, weather, fires, etc.
(D) Problems Created by Deforestation in India The following prob-
lems are created by deforestation in India:
(i) Decreasing levels of rainfall and rainy days
(ii) Increasing rate of soil erosion
(iii) Climate change
(iv) Loss of biodiversity
(v) Air pollution
(vi) Decline in watershed functions
(vii) Apparent loss of hardwood, fuel wood, and aesthetic stocks
(viii) Flooding
(ix) Desertification and sedimentation in rivers
(x) Long-term hydroelectric shortages
Annual deforestation rate is calculated by using the formula (Dirzo, 1992;
Vina, 1999; Ochoa-Gaona and Gonzales-Espinosa, 2000):
ÏÔ Ê AB - AE ˆ ¸Ô
1/t
r = Ì1 - Á1 - ˝ ¥ 100
Ë AB ˜¯ Ô
ÓÔ ˛
where r = Annual deforestation rate (%)
t = Number of years for the given period
AB = Area of forest at the beginning of the period
AE = Area of forest at the end of the period
∑ The deforestation trend is assessed by means of Indian topographical sheets
and satellite images.
∑ The socio-economic drivers of deforestation: Population density, education,
and infrastructure like road creation are socioeconomic drivers of
deforestation. This can be confirmed by statistical analysis.
example 2 Suppose for a particular area,

AB = 29458.83 ha; AE = 21397.96 ha; t = 10 years
Find annual deforestation rate.
Solution
ÔÏ Ê 29458.83 - 21397.96 ˆ Ô¸
1/10
r = Ì1 - Á1 - ˜¯ ˝ ¥ 100 = 0.315 ¥ 100
Ë 29458.83
ÓÔ ˛Ô
Thus, deforestation rate = 3.15 % per year.
(E) Economic Impacts of Deforestation As per BBC News, May 29,

2008; by 2050, damage to forests and other aspects of nature could (a) halve living
standards for the world’s poor, and (b) reduce global GDP by about 7%.
In developing countries, almost 3 billion people rely on forest wood for cooking
and heating. People in developed countries continue to use timber for building
houses and wood pulp for paper. In both developed and developing countries the
forest products industry is a large part of the economy. By conversion of forest to
agriculture, or over-exploitation of wood products, people get short-term economic
gains. However, it simultaneously results in loss of long-term biological productivity,
and hence a reduction in nature’s services.
(F) Environmental Impacts of Deforestation
(i) Atmosphere Less CO2 taken in, burned trees add even more CO2, which
traps heat, causes more evaporation, and this leads to more precipitation. More
sunlight reaches surface, less photosynthesis, increased risk of fire. This is responsible
for global warming, which in turn causes deforestation (a).
(ii) Hydrosphere Run-off increases, turbidity increases. More sediment at
mouth of rivers, more flash floods.
Increase of water temperature near river banks results in less availability of oxygen
in water ways. This is responsible for degradation of aquatic habitat (b) & (d).
(iii) Geosphere Increased erosion from water and wind, top soil carried away,
loss of minerals (C, N, etc.), soil depleted quicker, less wood for construction, fuel
and other products (b).
Fig. 2.4 Problems created by deforestation

(iv) Biosphere Loss of vegetation, change of food supply, decreased habitat,

decrease in number of species, decrease of diversity, decrease of pollinators and seed
dispersers, loss of human cultural diversity (c) & (d).
(G) Estimation of Socio-economic and Environmental Impacts of
Deforestation The assessment procedure consist of
(i) Description of the environmental state before the deforestation, representing
the baseline for assessment; refer (A).
(ii) Identification of the impacts of the deforestation on the environment; refer
(B).
(iii) Qualitative environmental assessment and classification of the effects on the
environment; refer (C).
(iv) Economic valuation of the environmental impacts, refer (D).
(v) Review for avoiding overlap with other sectors, refer (E).
(A) Goods and services provided by forest ecosystems must be clearly tabulated.
(B) Impact identification requires knowledge of cause–effect relationship. For
example, More deforestation means more sunlight reaches the surface, less
photosynthesis, more CO2 in atmosphere, global warming and increased
risk of fire (Fig. 2.4).
(C) To assess the effects of deforestation on natural capital (i.e. goods and
services), one can begin by separating its components: physical medium (air,
water, soil, climate), biotic medium (flora, fauna, human beings); perceptual
medium (landscape, cultural and scientific resources) and interactions among
the above-mentioned media.
(D) Environmental impact can be direct or indirect. Direct damage to the
environment can be estimated as the value of the assets effected.
� For permanent destruction, direct damage can be considered as the
commercial value of the assets when a market exists for them. For
example, if agricultural land is completely destroyed, the direct damage
will be the value of the land.
� When afforestation is possible, the direct damage can be approximated
by estimating the cost of afforestation.
� When a value cannot be assigned to assets for the estimation of direct
damage, estimates must be made by indirect means.
(E) Review the damage estimation for avoiding counting many and varied cases
of damage twice under the different social or economic sectors.
Notes:
(1) The above procedure is also applicable for estimating the socio-economic
and environmental effects of disasters.
(2) The above methodology takes into account several major constraints,
such as:
(i) too little time available for carrying out the assessment,
(ii) the lack of information on affected ecosystems, and
(iii) the shortage of markets for most environmental services.
(H) The Measures Taken for Conserving Forest Wealth

(i) Sustainable Forest Management (SFM) SFM is the use of the world’s
forests in such a way that they continue to provide resources in the present,
without depriving future generations of their use.
(ii) Forest Certification Be responsible consumers. Buy wood only from
companies that follow sustainable practices.
(iii) Involve Local Communities in Joint Forest Management (JFM) As local
communities want to continue to get the benefits they previously enjoyed,
they provide labour and help in conserving biodiversity. The Government
should provide them extractive reserves. These are protected forests in which
local communities are allowed to harvest fruits, nuts, medicines, fibres,
rubber, etc., in ways that do not harm the forest.
(iv) Improve Governance and Accountability The Government must take
bold political decisions and develop new civil society institutions to improve
governance and accountability regarding forest use. Stop harmful subsidies
to timber companies.
(v) Accelerate Education, Research and Training This is to ensure that SFM
and JFM can quickly become a reality.
2.3.3 Timber Extraction

Timber is a term used to describe clusters of trees. It is also used to describe wood
throughout its processing from the time it is cut down to the time it is used as a
structural material. It is a durable wood of high quality used for making sports
goods, doors, window frames, crates, plywood sheets, household utensils, coffins,
furniture and other items.
Timber extraction is the removal of timber from forests. It requires various cutting,
felling and hauling practices.
Logging is the work or business of felling and trimming trees and transporting
the logs to a mill.
(A) Classification of Timber Extraction Methods Usually, the follow-
ing types of timber-extraction methods are used:
(i) Clear Felling It is a controversial logging practice in which most or all trees
in a harvest are cut down. In clear felling, the aim is to create an even-aged group
of trees with commercial species dominating by removal of noncommercial trees by
cutting. Thus, clear felling means complete destruction of the native forest. All over
the world, industrial timber logging is being done by clear felling.
(ii) Handlogging It involves timber felling by hand-held chain saws. The
transport of logs from felling sites to log landing sites is also manual. It is practiced
in those forests that are either seasonally flooded or permanently waterlogged (e.g.
peat swamp forests). Many local people also use this method for clearing of forests
for agriculture.
(iii) Reduced–impact Logging Reduced-impact logging means timber

extraction is done selectively, carefully and in a planned manner. Reduced-impact
logging practices are based on the Food and Agriculture Organization (FAO)
guidelines. They help in minimising environmental damages through the selection
of site-sensitive harvesting techniques.
The Forest Stewardship Council (FSC) is an international body that provides
a framework for organisations certifying sustainable logging operations. The FSC
criteria also help policymakers to define national standards of logging.
(iv) Selective Logging In selective logging, only few large individual trees of a few
commercially marketable species are harvested. The other trees are left untouched till
the next harvesting so that forests are designated to remain production forests. Per
hectare, about 3 to 10 of the tallest trees are targeted in selective logging. However,
the damage done to the total forest areas may be as high as 50% because of lack of
planning, need to create access routes, dragging cut trees on the forest floor, etc.
(v) Mechanized Logging In it, heavy machinery is used for lifting, pulling and
transporting cut-trees operations. Sometimes logs are transported by trucks from
felling sites to log-landing sites. For this, roads are built to provide a network of
access routes,
Table 2.3 Timber-extraction methods
C H RI S M
Ø Ø Ø Ø Ø
Clear Hand Reduced-Impact Selective Mechanised
Felling Logging Logging Logging Logging
(B) Impacts of Timber Extraction

(i) Deforestation Logging roads are used by landless farmers to gain access to
rainforest areas. They clear the forest by slashing and burning to grow enough food
so as to keep them and their families alive. This ‘subsistence farming’ and commercial
logging is ranked as the biggest agent of tropical deforestation.
(a) Forest Degradation Poor logging practices results in a degraded forest.
(b) Forest Fires Timber extraction produces excess organic debris which
makes a forest more vulnerable to destruction in the event of fire.
(ii) Atmosphere Trees act as sinks for carbon dioxide. In the global carbon
cycle, forests provide the largest carbon-storage mechanisms. When the forests
are destroyed by timber extraction, the carbon-storage capacity is lost. Moreover,
through decay and burning, additional carbon is released into the atmosphere.
(iii) Harm to Nature Timber extraction results in forest fragmentation. It

promotes loss of biodiversity because some species of animals and plants require
large continuous areas of similar habitat to survive.
(iv) Climate Change Removal of forest cover leads to increased spring run-off
coupled with summer drought, soil erosion and landslips. This also results in hotter
summers and cooler winters.
(v) Soil Erosion and Siltation The tracks made by heavy machinery and the
clearings left behind by loggers are sites of extreme soil disturbance. From these
sites, heavy rain causes soil erosion. This causes siltation of the streams, rivers and
the forests. As a result, the lives of indigenous people, life-support systems and the
habitat of hundreds of birds and animals gets disrupted.
Case Studies
(i) Chipko Movement
‘Chipko’ in Hindi means hugging or embracing. Contractors used to make huge
profits, from the feeling of trees in the hills. The Chipko movement was the
hill communities’ response to the unfair and destructive nature of this contract
system. The Chipko movement spread through India during the 1970’s.
As per the folk-poet Ghansyam Returi, Chipko movement is
“Embrace the trees in the forests and save them from being felled! Save the
treasure of the mountains from being looted away from us!”
The slogan of the Chipko movement was
“What do the forests bear? Soil, water, and pure air!”
The Chipko movement ensured that the contract system was abolished and
the indiscriminate felling of trees stopped. The Forest Development Corporation
(FDC) department was formed which works for the welfare of hilly areas and the
people living there. It enlightened the people about the necessity of ecological
balance in the nature.
The Chipko movement took place under the leadership of Sunder Lal
Bahuguna (an environmentalist and journalist) and Chandi Prasad Bhatt in
Tehri Garhwal (Uttarakhand). Sunderlal along with his wife, Vimla, has given
his time and talent freely to work for the good of India. He has been the catalyst
of change, encouraging thousands of people to work without pay for the good of
India’s people and ecology, through non-violent resistance. As a Gandhian peace
worker, they do not resort to violence to achieve the change.
Chandi Prasad Bhatt encouraged the development of local industries based on
the conservation and sustainable use of forest weather for local benefit.
Forests in Uttarakhand district covered more than 81% of its geographical
area in 1950. The Government initiated the process of development by allowing
a pulp and paper mill, a plywood factory and a chain of hydroelectric dams on
rivers. Over-exploitation of forest resources by these industries and submergence
of huge forests and agricultural areas by dams resulted in shrinking of the forests
to nearly 25% of the district’s area by 1980. The poor, local population was forced
to displace. The conversion of the natural mixed forests into eucalyptus and teak
plantations dried up the water resources, directly affecting forest dwellers, and
resulted in poverty instead of intended development.
The Chipko protests in Uttar Pradesh achieved a major victory in 1980 with
a 15-year ban on green felling in the Himalayan forests of UP by the order of the
then Prime Minister of India (Mrs Indira Gandhi). Since then, the movement
has spread to many states in India. The movement has also helped in stopping
deforestation in the Western Ghats and the Vindhyas.
(ii) Appiko Movement
In Karnataka, the Chipko movement is known as Appiko movement, because
in Kannada, the local term for ‘hugging’ is appiko. The main objectives of the
Appiko movements are:
(a) Ulisu (to conserve),
(b) Belesu (to grow), and
(c) Balasu (rational use).
The importance of the Appiko movement can be understood from the fact
that it is trying to evolve a sustainable development strategy for conservation and
improvement of forest resources.
In September 1983, men, women and children of Salkani “hugged the trees”
in Kalase forest and gave birth to a new awareness all over southern India through
this Appiko movement. It uses various techniques to raise awareness like foot
marches in the interior forests, street plays, folk dances, etc. As a result of the
Appiko movement, the state government has banned felling of green trees in
the same forest areas. Only dry, dying and dead trees are felled to meet local
requirements.
The Appiko movement is also promoting afforestation on denuded lands. It is
also active in promoting rational use of the ecosphere.
(iii) The Bishnois
Jambhoji, a resident of a village near Jodhpur, had a vision in the fifteenth
century that the people’s interference with nature like felling of trees, killing of
animals would result in drought. Thereafter, he become a sanyasi and initiated
the Bishnoi sect. He came to be known as Swami Jambeshwar Maharaj. He laid
down tenets (including a ban on killing animals, a ban to the felling of khejri and
other trees) for his followers.
Once the Maharaja of Jodhpur sent his men to the area around the village
of Jalnadi to fell the trees as he required wood for building a new palace. When
Amrita Devi (a Bishnoi rural woman) saw this, she rushed out to prevent the
men and hugged the first tree, but the axe fell on her. Before dying, she uttered
the now famous couplet of the Bishnois, ‘A chopped head is cheaper than a
felled tree’. To prevent the Maharaja’s men from felling the trees, people from
83 surrounding villages rushed to the spot and by the end of the day more than
350 had lost their lives.
When the Maharaja heard about this, he was filled with regret and came to
the village to personally apologise to the people. He promised them that they
would never again be asked to provide timber to the ruler, no khejri tree would
ever be cut, and hunting of animals would be banned near the Bishnoi villages.
The village of Jalnadi thus came to be called khejari. The Bishnois have proved
that human lives are a small price to pay to protect the wildlife and the forests
around them.
(iv) The Green Belt Movement
Dr Wangari Maathai started the Green Belt Movement (GBM) in 1977 as a
grassroots tree planting programme to address the challenges of deforestation,
soil erosion and lack of water. Now, GBM is one of the most prominent women’s
civil society organisations, based in Kenya. The GBM advocates for human
rights, supports good governance and protects the environment through peaceful
democratic change.
In 2004, Dr Wangari Maathai became the first African woman and the first
environmentalist to receive the Nobel Peace Prize.
Across Africa, GBM has helped in the plantation of more than 40 million trees.
As a result, soil erosion has been reduced in critical watersheds, biodiversity-rich
indigenous forests have been restored and protected in thousands of acres, and
lakhs of women and their families are standing up for their rights and those of
their communities to live healthier and more productive lives through training in
forestry, food processing, beekeeping, etc.
In the next decade, the goal of GBM is to plant one billion trees worldwide. A
healthy natural world is at the heart of an equitable and peaceful society.
(v) Social Forestry
Thimmakka and Chikkanna were residents of Hulikal village in Karnataka, India,
and were childless. Frustrated from the taunts of neighbours for being infertile,
they decided to raise banyan (Ficus religiosa) trees as their children. Every year,
for many years, they planted 15 to 20 new saplings of banyan trees along a hot,
dusty 4 kilometre stretch between Huikal and Kudur villages in Karnataka.
Every morning, the couple set out—Thimmakka (the wife) with a pot atop her
head and another on her hip and Chikkanna (the husband) with two more pots
hanging from a pole he held over his shoulder. They watered the tiny plants and
placed thorn guards around their little wards to protect them from grazers. They
watered the trees everyday till they flourished. They refilled the pots from wells
and ponds along they way as their trees required about 50 pots of water a day.
They visited their plants at least once a week until the trees were 10 years old.
More than 45 years later, the banyan trees (the adopted children of Thimmakka
and Chikkanna) stretch all along the 4 kilometres between Hulikal and Kudur
villages. The trees are in fact a proud and memorable mark of their ‘parents’
dedication. They provide shade for the villagers, who often had to work on the hot
and dusty road. Chikkanna died a few years later and after five years, the couple
started receiving recognition. Thimmakka has received the National Citizen’s
and the Prime Minister’s Award for Social Forestry for the strong upbringing of
her many offspring.
Thimmakka proved that environmentalism is not exclusively for the wealthy
and privileged, but that it should be at the centre of everyone’s daily lives without
cultural restrictions or economic education.
2.3.4 Mining
Mining is the extraction (removal) of metals and minerals from the earth.
(A) Sustainable Mining Extraction and beneficiation of raw materials has
to be
∑ Environmentally compliant
∑ Socially acceptable ‘‘Sustainable”
∑ Economic
A mining operation is socially acceptable if
(i) It obeys standards in occupational safety and health
(ii) It is accepted by the society
(iii) It obeys national and international guidelines and laws
(iv) It provides resettlement help
(v) It considers cultural and social constraints
(vi) It provides suitable working conditions for the workers
A mining operation is economic if
(i) It fulfills the needs of the society with material and immaterial goods
(ii) It is working for the long-term maximisation of revenues and profit
A mining operation is environmentally compliant if
It does not impose any harm to the environment.
(B) Mining Process and the Environment Some of the major environ-
mental impacts of mining are a result of associated mining operations as summarised
in Fig. 2.5.
(C) Environmental Impacts of Mining Some of the major environmental
impacts of mining are the following:
(i) Ecological Impacts
(a) Degradation of Land Due to leaching out of toxic elements, the growth
of vegetation is adversely affected. Loss of fauna and flora is also observed.
(ii) Socio-economic Impacts
(a) Pollution of Water Resources Even when drainage is controlled, some
leaching and release of harmful elements (e.g. Pb, Cd, etc.) into the surface
and groundwater occurs. It affects the ecosystem stability adversely due to
alterations in water quality and availability.
(b) Pollution of Air Mining processes emit dust and gases which cause air
pollution. These air pollutants have adverse impacts on historical monuments
and religious places.
Fig. 2.5 Mining process and the environment

Impacts of Mining
Physical impacts Ecological impacts
∑ Landscape destruction ∑ Ecosystem degradation

∑ Soil erosion ∑ Loss of flora and fauna
∑ Land subsidence ∑ Deforestation
Socio-economic impacts
Positive Negative
∑ Employment ∑ Pollution and accidents

∑ Economic gains ∑ Health hazards
∑ Infrastructure ∑ Resettlement and
facilities rehabilitation issues
Fig. 2.6 Impacts of mining activities
(c) Problems in Rehabilitation of Affected Population It is one of the

biggest problems due to economic constraints.
To sum up,
Mines always cause environmental impacts
But ... it is usually cheaper to prevent the impacts than to deal with them after
they have already happened. It is easier to prevent the impacts if one knows about
them in advance.
Case Studies
(i) Impact of Coal Mining on Vegetation
Meghalaya, one of the seven states of North-East India, is honoured with rich
natural vegetation as well as large reserves of mineral resources.
In the early 1970s, coal mining was initiated in the Jaintia Hills district of
Meghalaya. Since then mining and the area affected by it is increasing day by day.
The dense forest areas were converted into open forests and the considerable area
of the forests was converted into a nonforest.
Extensive coal mining has led to landscape damage and damage to the
biological communities in enormous ways. The number of trees and shrub
species drastically decreased due to mining. The unfavourable habitat conditions
prevailing in the coal-mining areas has reduced the chances of regeneration of
species, thereby, reducing the number of plant species in the mined areas.
(ii) Jhansi Open-Cast Mining Site: Uttar Pradesh, India
The Bundelkhand region occupying about 71818 km2 in Uttar Pradesh is known
for its rich deposits of graphite, saltpetre, sand, etc. Presently there are around
325 active mining sites in the Jhansi district alone (2010).
Mining and its allied activities significantly contributed towards infrastructure
development and raising the living standards of the people.
Deforestation, dust generation, noise, air and water pollution as well as
resource depletion are common hazards associated with open-cast mining widely
prevalent in the Jhansi region.
(iii) Marble Mining and Drying of Lakes in Rajasthan
The Aravalli Hills are the lifeline of Haryana, Rajasthan, and Gujarat. They control
the climate and drainage systems of the region. The hills also act as a watershed
for the region. The hills are also known for their rich deposits of teak, marble and
granite. About 1,75,000 workers are employed in mining and related industries.
About 9700 industrial units are connected with mining in Rajasthan alone.
Over the past 20 years, the forest cover has been depleted by 90% in Rajasthan
due to large-scale mining. When the mines reach below the underground water
level, a cone of depression is formed that sucks water from the surrounding areas,
drying up wells and lakes and affecting agriculture.
The Rajasamand Lake in Rajasthan had not dried up for at least 300 years.
However, in 2001, this finally did happen because of a decade of marble mining
in the Rajnagar area. While mining has led to the depletion of water, mining
waste has destroyed fertile land.
(iv) Impact of Mining Activities on Labourers

Studies on mining activities in the Aravallis have shown that
(a) Labourers are not provided with any health care
(b) Tuberculosis, silicosis and other lung diseases are very common
(c) Diseases make labourers invalid and even kill them by the age of 40
(d) The condition of women workers (30–40%) and child labourers (10–15%)
is the worst.
(v) Impact of Mining on the Culture and Lifestyle of People
From the gold and copper project, 1000 m3 of conc. cyanide were released
into a river in 1984 on the OK Tedi Island in new Guinea. It caused extensive
environmental damage, devastated the ecosystem and destroyed the culture and
lifestyle of the native Wopkaimin people.
2.3.5 Dams and their Effects on Forest and Tribal People

A dam is a huge and giant barrier constructed across a river to obstruct its natural
flow. Consequently, an enormously large artificial lake is created to store water. The
water thus stored is utilised for multipurpose services such as power generation,
irrigation, flood and drought control, etc.
Construction of dams in countries like India and China displace a large number
of people because of the high population densities of these countries. In India,
dams account for 75–80% of displacement of about 4–5 crore people. Out of the
total people displaced, only 25% have been rehabilitated so far. Tribal people are
economically, socially and politically the weakest and the most deprived community
in India.
Some of the problems associated with effects of dams on tribal people are listed
below:
(i) No Human Rights Human rights violations create unrest among tribals.
(ii) No Basic Amenities They are forced to migrate to urban slums in search
of employment. They become landless labourers in rural areas. A majority
of tribal people end up with less income than before, less resources of
the common people, inferior houses, etc. They are forced to live without
drinking water, sanitation, health care, and other basic amenities.
(iii) No Benefit Sharing They hardly get to share the benefits of development
projects that cause their displacement.
(iv) No Home Tribal people have been forced to leave their ancestral homes
and go elsewhere.
(v) No Cultural Identity Tribal communities get dispersed, traditional sup-
port systems get broken and cultural identity gets devaluated because of dams.
Table 2.4 Problems associated with effects of dams on tribal people: Loss of
R A S H I
Ø Ø Ø Ø Ø
Rights Amenities Sharing Home Identity
All major dams are constructed in mountainous regions, where there is plenty of
rainfall. These places are covered with rich vegetation and forests.
The major effects of dams on forests are summarised below:
(i) The forests area which is supposed to get submerged is cleared off by the
contractors.
(ii) The forest is also cleared for approach roads, offices, residences and for
storage of construction material.
(iii) As more and more workers occupy the dam sites, forests are destroyed for
getting fuel and timber.
(iv) Irrecoverable Loss to Ecosystems and Biodiversity Forest fragmentation
causes serious irrecoverable loss of species and ecosystems. This is because
some species of animals and plants require large continuous areas of similar
habitat to survive.
2.4 WATER RESOURCES

Water resources are sources of water that are useful or potentially useful to humans.
Water is a prerequisite for the existence of life. Plants, animals, and human beings
cannot survive without water. Water is used in agricultural, household, industrial,
recreational and environmental activities. Water is essential for economic growth,
environmental stability, biodiversity conservation, food security and health care.
(A) The Water Cycle It describes the continuous movement of water above
and below the surface of the earth. It is driven by the sun.
The sun heats water in seas and oceans. Water evaporates into the air as water
vapour. Snow and ice can sublime directly into water vapour. Rising air currents
take the water vapours into the atmosphere where cooler temperatures help them to
condense into clouds. Air currents move clouds; they collide, grow, and fall out of
the sky as precipitation. Some precipitation falls as snow, and can accumulate as ice
caps and glaciers . Most water falls back into the oceans or onto land as rain where
the water flows over the ground as surface run-off. Much of the run-off is soaked
into the ground as infiltration. Some run-off is stored as fresh water in lakes. Some
run-off enters rivers in valleys in the landscape. Some water infiltrates deep into the
ground and replenishes aquifers. This helps in the long-term storage of freshwater.
Some groundwater finds openings in the surface of land and freshwater springs
come out. Some rainwater flows through rivers back into the ocean, where the water
cycle begins again.
Table 2.5 Water cycle
Significance of Water Cycle Problems Arising from the
Disturbances to the Water Cycle
(i) The water cycle helps in the maintenance of life (i) Maintenance of life and ecosys-
and ecosystems on the earth. tems on earth get disturbed.
(Contd.)
(Contd.)
(ii) The water cycle helps in the transport of (ii) Mineral transport to different
minerals from one part to different parts of parts of the globe gets disturbed.
the globe.
(iii) The water cycle purifies water by transferring (iii) Water purification process gets
water from one reservoir to another. disturbed.
(iv) The water cycle helps in the replenishing of the (iv) Replenishing of the land with
land with freshwater. fresh water gets disturbed.
(v) Processes such as erosion and sedimentation as- (v) Processes for reshaping the geo-
sociated with the water cycle helps in reshaping logical features of the earth get
the geological features of the earth. disturbed.
(vi) Through the evaporation and condensation (vi) Influence on climate gets
process, the water cycle helps in the cooling and disturbed.
warming of the environmental respectively.
2 Evaporation: The transformation of water from liquid to gaseous phase.

2´ Sublimation: The state change directly from snow or ice to water vapour.
3 Condensation: The transformation of water vapours to liquid water droplets creating fog and
clouds.
4 Precipitation: Condensed water vapour that falls to the earth’s surface as rain.
5 Surface run-off: The way by which water moves across the land.
6 Percolation: Infiltration of surface water for groundwater storage.
Fig. 2.7 The water cycle
(B) Sources of Water 97.5% of water on the earth is salt water in oceans.
Only 2.5% is fresh water. Sources of fresh water are briefly described below:
(i) Surface Water Water in a lake, river or freshwater wetland is known as
surface water.
(ii) Groundwater Fresh water located in the pore space of soil and rocks is
called groundwater.
(iii) Ice Caps and Glaciers Fresh water from ice caps and glaciers is relatively
inaccessible.
Earth’s water
Saline water Fresh water

(97.5 %) (2.5 %)
Icecaps and glaciers Groundwater Surface water

(68.7 %) (30.1 %) (0.9 %)
Lakes Swamps Rivers

(87 %) (11 %) (2 %)
Fig. 2.8 Distribution of the earth’s water
(C) Availability of Water The total water in the world is estimated to be

1400 ¥ 106 km3. Unfortunately, 97.5%
of this water is found in the oceans and
is too salty to drink. Of the remaining
2.5% fresh water, 2% is locked up in rel-
atively inaccessible ice caps and glaciers,
and 0.5% is groundwater and most of it
lies too far underground.
About 2 ¥ 105 km3 of freshwater
is found in lakes and rivers and 14 ¥
103 km3 of freshwater is found in the
atmosphere. The available freshwater is
distributed regionally as shown in Table
2.6.
The global overview of water
availability versus the population (Table
2.6) stresses the continental disparities,
and in particular the pressure put on the
Asian continent. This is because Asia
supports 60% of the world’s population
with only 36 per cent of the world’s
water resources. Fig. 2.9 World’s water content
Table 2.6 Water availability versus population

Continent Population Freshwater Availability
(i) North and Central America 8% 15%
(ii) South America 6% 26%
(iii) Europe 13% 8%
(iv) Africa 13% 11%
(v) Australia and Oceania < 1% 5%
(vi) Asia 60% 36%
Availability of Water in India India is the wettest country in the world, but
rainfall is highly uneven with space and time. Rainfall is high in the North-East but
extremely low in Rajasthan. Out of 4000 billion cm3 rainfall received, about 600
billion cm3 is put to use so far.
With 16% of the world’s population, India has only 4% of global water resources.
The city of the Delhi gets 60 hours of rain a year, and only 11 hours of it are
contained while the rest is wasted. Every monsoon we see flooded underpasses and
buses floating by.
(D) Causes of Water Crisis in the World The causes for shortage of water
leading to water crisis are the following:
(i) Growing population and with better lifestyles, per capita use of fresh water is
increasing, causing shortage of water.
(ii) Spatial and temporal variations in available water is also responsible for water
crisis.
(iii) Freshwater resources are reduced by pollution. Industrial wastes, chemicals,
human waste and agricultural wastes (fertilisers, pesticides and pesticide
residues) are disposed off within water.
(iv) Increase in extreme weather conditions like floods, droughts, typhoons, cyclones,
etc., are also responsible for worsening of water quality and availability.
Recently, it is estimated that
∑ Climate change will account for about 20% of the increase in global water
scarcity
∑ 50% of the population of developing countries are exposed to polluted water
sources
(E) Importance of Water Next to air, water is the most essential thing for our
survival. We must drink water to avoid dehydration which means less or insufficient
levels of water and important body salts of sodium and potassium in our body. The
kidneys, brain, heart and other important body organs cannot function property
without salt and water.
Water is also helpful in maintaining the relatively constant body temperature
through the homeostasis process. It helps in avoiding upsetting of metabolic
reactions by preventing sudden changes in temperature.
Water helps in the digestion process. Different types of food products, after being
broken down to simple molecules (e.g. large starch molecules are broken down to
simple sugars) are solubilised in the universal solvent ‘water’. Different enzymes
facilitate this digestion process.
Oxygen gas is also dissolved in water to some extent. This Dissolved Oxygen
(DO) helps in the respiration process of many organisms who live in water and
spend most of their time underwater.
“Life is impossible without water. It is needed for health, ecosystem services, economic
development, poverty reduction, protection of greenery, production of food and imparting
of aesthetic beauty.”
(F) Impacts of Over-utilisation of Underground and Surface Water
The over-utilisation of underground and surface water has the potential to alter,
sometimes irreversibly, the integrity of freshwater ecosystems. Some of the major
impacts are summarised below:
(i) Loss of Integrity of Freshwater Ecosystems Human activities for infra-
structure development like creation of dams, land conversion, etc., are re-
sponsible for this loss of integrity of freshwater ecosystems. Water quality
and quantity, fisheries, habitats, etc., are at risk due to this loss of integrity.
(ii) Risk to Ecosystem Functions Population and consumption growth
increases water abstraction and acquisition of cultivated land. Virtually all
ecosystem functions including habitat, production and regulation functions
are at risk.
(iii) Depletion of Living Resources and Biodiversity Overharvesting and ex-
ploitation causes groundwater depletion, collapse of fisheries. Production of
food, quality and quantity of water and supply of water gets badly affected
by these depletions of living resources and biodiversity.
(iv) Pollution of Water Bodies Release of pollutants to land, air or water
alters chemistry and ecology of water bodies. Greenhouse gas emissions
produce significant changes in run-off and rainfall patterns. Because of water
pollution, water supply, habitat, water quality, food production, climate
change, etc., are at risk.
2.4.1 Uses and Overuses of Water Resources

(A) Uses of Good-Quality Water Good-quality water is needed for all di-
rect or indirect uses of water as illustrated in Fig. 2.10.
According to the Union Ministry of Water Resources (MoWR), 80 per cent of
India’s utilisable water is devoted to agriculture, mostly for irrigation. Demand from
the domestic sector is about 5% of the annual freshwater withdrawals in India. The
industrial sector in India is the second largest user of water.
As a result of growing sectoral demands and declining water supplies, competition
is growing rapidly.
From public systems, allocation of water is not based on fundamental rights
consideration or social, economic or environmental considerations, Thus, water
allocation is inequitable. Growing inequity in access to and control over water leads
to conflicts among different sectors.
Fig. 2.10 Direct and indirect uses of water resources by humans and ecosystems
The poor need water for both domestic as well as productive purposes which
include growing food, fruit, vegetables, rear livestock, etc. The rich residents of
cities consume around 200 litres per capita per day. It is believed that finding ways
of providing similar quantity of water in support of the livelihoods of the rural poor
is vital.
India’s supply of water is rapidly decreasing mainly due to mismanagement
of water resources, although over-extraction and pollution are also significant
contributors.
As per Central Water Commission (CWC) assessment, 2011; water availability
in India is 1869 billion cubic metres or 1869 km3.
(B) Sectoral Demand of Table 2.7 Water requirement for various sectors
Water As per the ministry Sector Water demand in Billion Cubic Metres
of Water Resources (MoWR) Year 2010 Year 2025
assessment, 2000; water re- Irrigation 688 910
quirements for various sectors Drinking water 56 73
in India is tabulated here. Industry 12 23
Over-exploitations of water re- Energy 5 15
sources and the problem of avail- Others 52 72
ability of safe drinking water: Total 813 1093
(i) Excessive Withdrawal from Surface Waters Size of the sea is shrinking
(e.g. the Aral sea in the former Soviet Union) primarily by the diversion of the
inflowing rivers to irrigate water-intensive cotton and rice crops.
In 2007, about 60% of the Aral Sea’s volume had been lost, its depth had declined
by 14 metres. Moreover, its salt concentration had doubled.
(ii) Inefficient Use of Freshwater Excessive consumption by individuals,
leakage in water delivery systems, inefficient use by industry and poor irrigation
practices can all contribute to situations where there is not enough water for all
uses.
(iii) Excessive Withdrawal of Water from Underground Aquifers Exces-

sive freshwater abstraction along much of the west coast of India has allowed sea
water to enter aquifers. It resulted in making the water saline and unfit for human
use. The above problem has worsened due to leaching of excess irrigation water
containing pesticides, fertilisers, etc., into these aquifers.
(C) Water Conservation
“Water conservation is the most cost-effective and eco-friendly way to reduce our
demand for water.”
(i) Need for Water Conservation On an average, a citizen in most parts of the
world is allocated 2.5 gallons of water per day for sustainability. However, the aver-
age American citizen uses 80–100 gallons of water per day. The poor do not have ac-
cess to safe drinking water. More than 4000 children are dying every day as a result
of diarrhoeal diseases caused from unsafe drinking water, lack of access to sanitation
and inadequate availability of water. Thus, it is very essential to conserve water.
Fig. 2.11 Water conservation

(i) Measures to Conserve Water
(a) Recharge groundwater by harvesting rainwater.
(b) Use water wisely for household, agricultural and domestic purposes.
(c) Reuse water whenever possible. For example, waste water after bath can be
used for the toilet.
(d) Avoid transmission and distribution losses by checking leaks in pipes, hoses,
etc.
(e) Prevent flow of untreated sewage to lakes and rivers. This will reduce the
likelihood of water pollution and help in water conservation.
(f) Collect water by building dams and reservoirs, and digging wells.
(g) Use drip irrigation, precision sprinklers for agriculture. Practice organic
farming.
(h) Adopt fairer policies for treatment, access and pricing of water.
(i) Prevent flow of industrial effluents to natural water resources to avoid water
pollution.
(j) Do protect forests to protect rivers, lakes, wells and other sources of water.
(D) Quality Aspects
(i) Impacts of Poor Water Quality Poor water qualities are responsible for
(a) public health hazards,
(b) damage to ecosystems, and

(c) adverse economic consequences.
A good status of water biology and healthy aquatic organisms are necessary for
obtaining a good status of water quality.
(ii) Characteristics of a Good-Quality Water
(a) It is transparent, colorless and odourless.
(b) It has sufficient oxygen concentration for marine life to survive.
(c) It is free from bacteriological contamination.
(d) It is free from any water pollution.
(e) It is free from excessive nutrients like N, P, etc., which are responsible for
eutrophication.
(f) It is fit for the intended use.
(E) Self-Purification of Rivers A variety of plant and animal species live in
seas and rivers. If pollution does not attain a critical level, water can purify itself, i.e.
progressively eliminate polluting agents. The phenomena of filtration and oxida-
tion, combined with the action of organisms (insects, bacteria, plants, etc.) living
in the water and on the banks helps water maintain its quality and preserve its eco-
system’s balance.
Fig. 2.12 River self-purification mechanisms
Various river-self purification mechanisms are described below:

(i) Phyto-remediation Aquatic plants and vegetation on the river banks ab-
sorb (nitrate, phosphate and other nutrients) and remove pesticides and heavy
metals from water. In this way quality of water in the river is largely improved.
(ii) Aeration When a river runs through hills, turbulence mixes air into water
increasing the dissolved oxygen (DO). The increased DO concentration
facilitates many chemical and microbiological processes in water to reduce
the pollutant concentration.
(iii) Sedimentation In this mechanism, sand in the river bed acts as a sink for
the pollutants. From the hills, when river reaches flat lands, it spreads, its
velocity reduces and suspended pollutants settle on the sand bed.
(iv) Adsorption Pollutants are adsorbed onto sand particles, plant surfaces,
rocks, etc., and thereby their concentrations get reduced in the river water.
(v) Dilution When a polluted river is joined by less polluted tributaries or
during the rainy seasons, the volume of water in the river is increased. It
reduces the concentrations of pollutants by dilution process.
(vi) Floatation After rapid mixing of water in falls, air bubbles act as vehicles
to lift many pollutants to the water surface in the form of froth (or a layer of
foam). This froth is exposed to the atmosphere, and it facilitates oxidation

of pollutants to less harmful forms. The top layer is also directly exposed to
sunlight; so either by increased temperature or due to various photochemical
reactions, volatile organic compounds are removed from the top layer. At
different sections of the river, various artificial traps help in the removal of
this froth and thus rivers get self-purified.
(vii) Microbial Degradation The shallow and turbulent water results in high
aeration of water. It helps in growth of bacteria and other microorganisms.
They help in river purification by microbial degradation of pollutants.
(F) Major Water-Quality Issues Wastes introduced by humans into rivers,
lakes, groundwater aquifers and the oceans modify the environmental water quality
and make huge quantities of water unsuitable for various uses.
(G) Major Factors Responsible for Water-Quality Degradation

(i) Insufficient and incomplete treatment of domestic and industrial waste
water
(ii) Eutrophication
(iii) Pathogens, and pesticide contamination
(iv) Stagnation of domestic sewage and contamination of groundwater
Fig. 2.13 Important quality issues of water
(H) Water-Borne Diseases Water-borne diseases are illnesses caused by con-

suming water contaminated by pathogenic microorganisms.
Fig. 2.14 Illnesses caused by consuming contaminated water

Often lack of access to hygienic water, poor sanitation and rise in population of
pathogenic microorganisms like protozoa, viruses, bacteria and intestinal parasites
breeding in on water are considered the main causes of water-borne diseases.
According to the World Health Organization, diarrhoeal disease is responsible
for the deaths of 1.8 million people every year and a majority of them are children
in developing countries.
A few water-borne diseases are summarised in Table 2.8.
Table 2.8 Water-borne diseases
S.No. Water-borne disease Caused by Symptoms
1. Giardiasis Giardia intestinalis Severe abdominal cramps, diarrhea,
(Type of diarrhoea) nausea, greasy stool, gas, etc.
2. Amoebiasis Entamoeba Extreme abdominal discomfort, loose
(Type of diarrhoea) histolytica (Protozoa) stools, bloating, weight loss, abdominal
pain, etc.
3. Cryptosporidiosis Cryptosporidium Mild fever, weight loss, diarrhoea, vomit-
(Type of diarrhoea) parvum (tiny parasites) ing, nausea
4. Cholera Vibro cholerae Sudden onset of acute diarrhoea, which
(bacteria) may lead to excessive dehydration, kid-
ney failure and finally, even death
5. Gastroenteritis or Noroviruses Low grade fever, diarrhoea, frequent
stomach flu vomiting, dehydration, stomach or
abdominal cramping
The best ways to prevent water-borne diseases are

(i) avoid drinking untreated water,
(ii) avoid consuming undercooked food,
(iii) maintain good personal hygiene (e.g. wash hands before eating), and
(iv) educate for clean sanitation.
Fig. 2.15 Control of water-related diseases
(I) Fluoride Problem in Drinking Water

At low concentrations in drinking water, fluoride has beneficial effects on teeth.
But excessive exposure to fluoride in drinking water can give rise to number of
adverse effects. Although the concentration (mg/litre) of fluoride added to water can
be controlled, but we cannot control the dose (mg/day). This is because one cannot
control how much water people drink or how much fluoride they get from other
sources.
(i) Sources of Fluoride

(a) Fluoridated water supplies
(b) Food processed with fluoridated water
(c) Mouthwash enhanced with fluoride
(d) Toothpaste enhanced with fluoride
(e) Food supplements
(ii) Fluoridation is not Necessary
(a) The level of fluoride in mother’s milk is 0.004 ppm. It means a bottle-fed
baby, where fluoridated tap water (with 1 ppm fluoride) is used to make up
the formula milk, will get 250 times more fluoride than nature intended.
(b) Fluoride works from the outside of the tooth, not from inside the body, so
it is not required to swallow fluoride or drink fluoridated water.
(iii) Fluoride’s Dangers Fluoride damages teeth, bone, brain and endocrine
system. It may cause osteosarcoma.
Table 2.9 Dangers of fluoride consumption
Concentration of Fluoride Observed Effects
in Drinking Water
(i) At 0.7 ppm Early manifestation of skeletal fluorosis.
(ii) At 0.9 ppm Lowered IQ in children with borderline iodine deficiency.
(iii) At 1.0 ppm ∑ Dental fluorosis impacts 30+% of children
∑ Increased cortical bone defects in children
∑ Osteosarcoma in young men.
(iv) At 1.5 ppm Doubling of hip fracture rates.
(v) At 1.8 ppm Lowering of IQ in children.
(vi) At 2.3 ppm Lowering of thyroid activity
(vii) At 4.0 ppm ∑ Enamel damage with severe fluorosis (proven).
∑ Increased fractures in susceptible groups (probable).
∑ Skeletal fluorosis, stage II (possible)
(a) Fluoride damages the teeth A permanent discoloration and mottling of

the tooth enamel (dental fluorosis) is caused by a child’s ingestion of fluoride
(0.5–1.5 ppm) before its permanent teeth have erupted.
(b) Fluoride damages the bone In an area of high natural levels of fluoride
(1.5–5.5 ppm), fluoride can weaken bone and increase the risk of fractures.
(c) Fluoride damages the brain Fluoride lowers the IQ of children, even
when present at 1.8 ppm in water. It is apparent that fluorides have the
ability to interfere with the functions of the brain.
(iv) Defluoridation of Water Defluoridation of water can be carried out by
(a) Reverse osmosis filtration
(b) Activated alumina defluoridation filter
(c) Nalgonda technique
(J) Pesticide Removal Methods from Drinking Water
Water contaminated or suspected of being contaminated by pesticide and synthetic/vol-

atile organic compounds can be purified using following methods shown in Fig. 2.16.
Fig. 2.16 Pesticide removal methods from drinking water
2.4.2 Floods
Waterways are formed slowly over time, and their size is proportionate to the
amount of water that normally accumulates in that area. Sometimes, due to excessive
runoff from precipitation or snowmelt or by coastal storm surges or other tidal
phenomenon, there is suddenly a much greater volume of water. As a result, the
normal waterways overflow, and the water spreads out over the surrounding land.
This anomalous accumulation of water in an area of land is called flood.
Flood can be defined as a temporary rise of the water level, as in a river or lake or
along a sea coast, resulting in its spilling over and out of its artificial or natural confines
onto land that is normally dry or flood is a temporary covering by water of land not
normally covered by water.
(A) Effects of Flood
The effects of flood are briefly described below:
(i) Primary Effects Flood can cause either physical damage or casualties.
(a) Physical Damage Flood can damage any type of structure resulting in physical
damage to canals, bridges, sewerage systems, roadways, cars, buildings, etc.
(b) Casualties Humans and animals die due to drowning. Floods can also
cause casualties through epidemics and water-borne diseases. The spawning
grounds for fish and other wildlife can become polluted or completely
destroyed.
(ii) Secondary Effects Secondary effects of floods are briefly summarised below:
(a) Contamination of Water Clear drinking water becomes scarce because of
contamination of water due to floods.
(b) Spread of Water-borne Diseases Floods are responsible for unhygienic

conditions leading to various diseases.
(c) Loss of Harvest The entire harvest can be lost due to floods leading to
shortage of food crops and this badly affects the food supplies.
(d) Death of Some Nontolerant Tree Species Floods can lead to suffocation
and death of some nontolerant tree species.
(iii) Tertiary Effects / Long-term Effects Floods are responsible for food
shortage, leading to price increases. They are also responsible for temporary decline
in tourism. Money is also, needed for rebuilding any type of structure damaged by
flood. All the above effects (where economic hardship in concerned) is discussed in
tertiary effects or long-term effects.
Fig. 2.17 Effects of flood
(B) Benefits of Floods The more frequent and smaller floods can bring fol-
lowing benefits:
(i) Water Availability Floods helps in recharging of groundwater. Flood
waters provide much-needed water resources in arid and semi-arid regions where
precipitation events are unevenly distributed throughout the year.
(ii) Ecosystem Services Specially freshwater floods play an important role in
maintaining ecosystems in river corridors and in maintaining floodplain biodiver-
sity.
(iii) Increase in Soil fertility Floods help in making the soil more fertile by
providing nutrients to soil.
(iv) Improved Fisheries Flooding adds a lot of nutrients to lakes and rivers
which help in improved fisheries for some years. Fish, like weather fish, make use of
floods to reach new habitats.
(v) Benefits to Birds Birds profit from the boost in production caused by
flooding.
(vi) Higher Viability of Hydro-energy Projects The viability for hydrological
based renewable source of energy is higher in flood-prone regions.
(C) Flood Disaster Impact Minimisation

(i) If it has been raining hard for several hours, or steadily raining for several
days, individuals must listen carefully to the radio or TV flood forecasts
issued by the Central Water Commission.
(ii) They should listen to and follow the instructions of the emergency services.
(iii) They should extend all possible help to the administrative and engineering
agencies of the states/union territories to take appropriate measures.
2.4.3 Drought
Drought may be defined as the deficiency of rainfall (relative to the statistical multi-year
average for a region ) over an extended period of months or years.
(A) Types of Drought
Fig. 2.18 Types of drought
Drought can be classified into the following types:

(i) Meteorological Drought It is brought about when there is a prolonged
period with less than average rainfall. As per the India Meteorological Department
(IMD), meteorological drought occurs when the seasonal rainfall received over an
area is less than 75% of its long-term average. The drought can be classified as
‘moderate’ or ‘severe’ depending on the rainfall deficit between 26% to 50% or
exceeds 50% respectively.
Usually, meteorological drought precedes the other kinds of drought.
(ii) Agricultural Drought It is a drought that affects crop production or the
ecology of the range. It is caused by extended period of below-average rainfall result-
ing in a shortfall in water for the crops. It is typically witnessed after a meteorologi-
cal drought but before a hydrological draught.
(iii) Hydrological Drought It is brought about when the water reserves available
in sources such as reservoirs, lakes or aquifers fall below the statistical average. It
tends to show up more slowly because it involves stored water that is used but not
replenished.
(B) Consequences of Drought
The impacts of drought are briefly described below:
(i) Impact on Agriculture Droughts are responsible for diminished crop growth
or diminished production yields due to lack of water for irrigation. Famine may also
be caused.
(ii) Impact on Environment When drought hits an area suffering from

desertification and erosion, dust storms and/or dust bowls result which further
erode the landscape. Drought also affects both terrestrial and aquatic wildlife
through habitat damage.
(iii) Impact on Health Drought is responsible for malnutrition, dehydration
and related diseases. Drought can also reduce water quality, because lower water
flows reduce dilution of pollutants and increase contamination of remaining water
sources.
(iv) Social Impacts Subsistence farmers are forced to migrate during drought
because they do not have alternative food sources. Mass migration results in internal
displacement and international refugees. Droughts are also responsible for snake
migration and increases in snakebites. In totality, a situation of social unrest arises
because of drought. A war can also happen over natural resources including water
and food.
(v) Economic Impacts Droughts lead to reduced electricity production due to
reduced water flow through hydroelectric dams and insufficient available coolant for
power stations. Droughts also lead to shortages of water for industrial users
Fig. 2.19 Effects of drought
(C) Strategies for Mitigation of Drought Impacts Society’s vulnerabil-

ity to drought is minimised through the following actions:
(i) An artificial technique of cloud seeding helps in inducing rainfall.
(ii) For consumption or irrigation, desalination of sea water can be done in times
of scarcity.
(iii) Carefully planned crop rotation can help to minimise soil erosion. This also
allow farmers to plant less water-dependent crops in drier years.
(iv) Collection and storage of rainwater through rainwater harvesting is very
useful.
(v) Regulating the use of water-intensive home maintenance tasks and the use of
sprinklers, hoses, etc., on outdoor plants.
(vi) Redirecting rivers for irrigation in drought-prone areas.
(vii) Treatment and purification of sewage wastewater for reuse.
(viii) Continuous observation of rainfall levels and comparisons with current

usage levels can help prevent man-made drought.
2.4.4 Conflicts Over Water

Water might be the source of the world’s next big conflict. This is because fresh
water availability is limited but its demand is rising day by day.
(i) Infrastructure Failure The cost and environmental risks due to failure of
drinking and waste water infrastructure are very high, costing billions of rupees.
Fig. 2.20 Demand for water
(ii) Rapid Urbanisation It requires significant investment in water infrastructure

in order to deliver water to individuals and to process the wastewater so as to avoid
unacceptable public health risks.
(iii) Population Growth The demand of water for residential and industrial
purposes increases with increase in population.
(iv) Increasing Affluence Increasing affluence especially in India and in China,
inevitably means more water consumption. Expansion of business activity requires
more water supply.
(v) Climate Change Climate change poses a series of risks to water availability
as a result of the following:
(a) Rising temperatures could increase the rate of evaporation from surface
waters and reservoirs and lead to loss of freshwater held in glaciers.
(b) Increased rainfall might come in the form of storms that lead to floods.
(c) Climate change could increase annual precipitation and make more freshwater
available in some places leading to difficulty in water management systems.
Where water crosses cultural, economic, political or legal boundaries, the stage is
set for disputes between different users. The users try to safeguard access to a vital
resource, while protecting the natural environment.
Management and transformation of water conflicts require implementation of
right strategies for anticipation, addressing and mediation between competing users.
If the strategies are not implemented, the conflicts over water are likely to become
more frequent, more intense and more disruptive around the world.
Water conflicts in India can be classified as per the following themes:
Conflicts over (a) equity, access and allocations, (b) water quality, (c) dams and
displacement, (d) privatisation, (e) contending water uses, (f) sand excavation and
mining, (g) trans-boundary conflicts, and (h) micro-level conflicts are also present.
Some specific examples of conflicts over water:

(i) Conflict between Poor and Rich The rural peasants are poor and only
require a pot full of drinking water. The urban elite is rich and uses large quantities
of water for meeting the requirements of water-intensive sewage systems, space
cooling, gardening, etc. This results in conflict.
(ii) Conflicts between Agricultural Usage of Water Conflict also exists be-
tween water-intensive cultivation of commercial crops for high cash returns and wise
water use for protective irrigation of necessary food crops essential for survival.
(iii) Interstate Conflicts Sometimes water projects of upstream states influence
the quantity and quality of water flow in the basin. This reduces the possibilities of
water use by downstream states resulting in inter-state conflicts.
(iv) Intrastate Conflicts State-planned extraction of timber or minerals in the
river catchment affect the river flow and generate conflicts downstream.
State-planned agricultural production based on large irrigation projects to
generate marketable surpluses of cash crops conflicts with people’s needs for local
food production.
(v) Across Borders Conflicts India, Bangladesh and Nepal are disputing the best
use of water of the Ganges–Brahmaputra basin. India and Nepal want to exploit the
basin’s huge hydroelectric power-generating potential, whereas Bangladesh wants
the water management in such a way so as to minimise water shortages during dry
months and flooding during monsoon months.
2.4.5 Dams—Benefits and Problems

(A) Positive Impacts of Dams
(a) Flood Control Dams help in controlling river flow and flooding.
(b) Ecosystem Services Some dams help in creating new wetlands, new opportu-
nities for fishing and recreation in the reservoirs.
(a) Hydroelectricity Generation Dams are useful in generation of electricity.
(b) Help in Solving Problems of Hunger and Starvation About 16% of the
world’s food comes from land irrigated from dam reservoirs.
(c) Water Supply Dams ensure a year-round water supply.
(B) Negative Impacts of Dams
(a) Seismic Tremors The hydraulic pressures generated by deep reservoirs is
sufficient to change the seismicity of the region. Earthquakes of magnitude equal to
or greater than of 5 on the Richter scale seem to occur if the rate of water loading in
the reservoir exceeds 13 m per week.
(b) Evaporation Losses The reservoir of the dam provides more surface area for
evaporation. The loss of water due to evaporation is very high. As salt does not
evaporate, the remaining water becomes more saline.
(c) Salinisation of the Soil Use of saline water from dams for irrigation increases
the rate of salinisation of the soil.
Fig. 2.21 Socio-economic and ecological impacts of dams
(d) Landslips The rise in water level can destabilise the geodynamic situation
leading to substantial landslips.
(e) Silting Generally, a turbulent stream feeds the reservoir of a dam. A rapid
stream always carries some soil particles in suspension because of much up and
down movement of water. However, water in the reservoir is calm and slow moving.
As a result, most of the sediment that enters the reservoir from the run-off that feeds
it, settles at the bottom at the rate of 10 cm per year. At such a rate, the lakes behind
high dams can last up to hundreds of years, though not forever.
(a) Increase in Water-related Diseases Water impoundments for dams may pro-
vide breeding sites for the vectors. This leads to transmission of malaria and schistoso-
miasis and spread of onchocerciasis in populations living near dam spillways.
(b) Low Efficiency Most of the world’s large dams have been unable to achieve
the social, technical and economic objectives for which they were designed.
2.5 MINERAL RESOURCES

“Natural resources in the form of minerals are known as mineral resources.” They
include the ores of base metals such as copper, iron and lead as well as strategic
and critical metals such as chromium, titanium, platinum, cobalt, manganese,
palladium, etc.
2.5.1 Minerals and Their Classification

Minerals are naturally occurring, inorganic, solid, crystalline substances which contain
a specific composition of elements.
A mineral which can be extracted and processed at a profit is known as an ore.
(A) Types of Minerals
Minerals are broadly classified
into two categories: metallic and
nonmetallic. Metallic miner-
als are further sub-divided into
ferrous and nonferrous materi-
als. Nonmetallic minerals com-
prise of mineral fuels, precious
stones, etc. Fig. 2.22 Classification of minerals
(B) Importance of Minerals
(i) Almost all rocks are made of minerals.
(ii) They have high aesthetic value, e.g. gemstones.
(iii) They have natural resource value:
(a) Minerals are sources of metals needed for electronic manufacture,
airplanes, cars, etc.
(b) Minerals are raw materials for making window glass, plaster, etc.
(C) Mineral Resource of India India produces and works with roughly 100
minerals, which are an important source for earning foreign exchange as well as
satisfying domestic needs.
We import graphite, mercury, cobalt, etc., and export iron ore, granite, bauxite,
titanium, manganese, etc.
The distribution of minerals in the country is uneven and mineral density varies
from region to region.
Coal, iron ore, manganese, mica, bauxite, copper, etc., are found in the North-
Eastern peninsular belt located in Chhotanagpur Plateau and the Orissa Plateau
covering the states of Jharkhand, West Bengal and Orissa. These regions are called
the mineral heartland of India.
Gems, marble, coal, mica, graphite, manganese etc. exist in large quantities
in Central Belt located in Chattisgarh, Andhra Pradesh, Madhya Pradesh and
Maharashtra. The central Belt is the second largest belts of minerals in the country.
According to the 2008 Ministry of Mines estimates:
∑ India ranks 2nd in the production of chromite, barites
∑ India ranks 3rd in the production of coal and lignite,
∑ India ranks 4th in the production of iron ore,
∑ India ranks 5th in the production of bauxite and crude steel,
∑ India ranks 7th in the production of manganese, and
∑ India ranks 8th in the production of aluminium.
2.5.2 Environmental Effects of Extracting and

Using Mineral Resources
The impacts on forest, land, occupation, water, ecological functions, rehabilitation
of population, or impact on flowers due to pollution created during extraction and
use of mineral resources are
(i) Deforestation including to loss of flora and fauna.
(ii) Degradation of land due to excavations.
(iii) Occupational health hazards.
(iv) Pollution of ground and surface water resources due to accidental or periodic
discharge of pollutants.
(v) Damage to local ecological functions, nutrient cycling and biodiversity due
to alterations in water availability or quality.
(vi) Problem in rehabilitation of affected population.
(vii) Pollution of air due to emission of dust and poisonous gases during mining
and processing stages. Problems in providing living environment and clean
water, air, etc., for the survival of large number of workers who have migrated
nearby mine sites.
(viii) Problems in the safe disposal of tremendous amounts of solid waste generated
during mining.
2.5.3 Conservation of Mineral Resources

The mineral resources are very essential for the growth and development of a country.
The ever-increasing population in the world with improved lifestyles are responsible
for the rapid consumption of mineral resources. The geological processes of mineral
formation are so low that the rates of replenishment are very small in comparison to
the present rates of consumption. Thus, mineral resources are valuable but they will
be available for a limited time.
A sincere effort has to be made in order to use the mineral resources in a planned
and sustainable manner. The following four steps are very useful for the conservation
of mineral resources:
(i) Encourage use of improved technologies so as to reduce waste generation.
(ii) Encourage recycling of metals.
(iii) Regulate the use of mineral resources.
(iv) Reduce the purchase of unwanted products made from mineral resources.
(v) Encourage research for providing suitable ecofriendly alternatives for fossil
fuels, metals, etc.
These are known as 4R¢s for the sustainable use of mineral resources.
2.6 FOOD-SECURITY RESOURCES

Food security is defined as the physical and economic access to sufficient, safe, nutritious
food for maintaining a healthy and active life.
(A) Pillars of Food Security
There are three pillars on which food security is built:
(i) Food Availability It means sufficient quantities of food should be available

to people to meet their dietary needs as well as their food preferences. Food can be
made available from local, regional and international sources. Availability of food is
governed by food production, food processing, food trade, food storage, etc.
(ii) Food Access It means people at all times should have physical and economic
access to sufficient, safe and nutritious food. Food access is governed by marketing,
transport, purchasing power, etc.
(iii) Food Use It means people must have knowledge of basic nutrition and
care to maintain a healthy and active life. Food utilisation requires nutritious food
choices, food safety and quality, clean water and proper sanitation.
(B) Food Security can be Achieved by Policies, Agreements, Imports
and Distribution of Food
(i) Implementing appropriate food, agriculture and rural development policies
with conservation of natural resources that will facilitate food security in the
long run.
(ii) Permitting appropriate international agricultural agreements.
(iii) Ensuring that the imported food products
(a) are of acceptable quality and safe to eat,
(b) does not reduce agricultural employment levels, and
(c) permit protection of national food security.
(iv) Facilitating proper distribution of sufficient, safe and nutritious food.
(C) Threats to Food Security Threats to food security are summarised below:
(i) Declining productivity, increasing poverty and declining income from
traditional crops
(ii) Loss of preferences
(iii) Growing incidence of food-related diseases
(iv) High dependence on imported food
2.6.1 World Food Problems

According to Food and Agriculture Organization (FAO) estimates, on an overage,
the minimum calorie requirement of a healthy man is 3000 kcal/day and of a healthy
woman is 2200 kcal/day.
(A) Undernourishment
If a person receives less than 90% of this minimum calorie requirement then the
person is undernourished. Thus, undernourishment means to receive less calories
than needed.
As per WHO, almost one-third of all children under five years of age are
undernourished in developing countries.
Effects of Undernourishment
(i) Undernourished persons have less energy for doing any kind of work. They
are susceptible to diseases, their body becomes weak and they frequently fall
sick. They look old even at a young age.
(ii) Undernourished children suffer from the following problems: social

inferiority complex, slow body growth, mental retardness, illness, delayed
adulthood, etc.
(B) Malnourishment
It means lack of essential nutrients (like proteins, vitamins, lipids, minerals, etc.) in
the diet.
It may lead to the following problems:
Malnourished persons are more susceptible to diseases, they have less strength to
function productively, and they face abnormal growth.
According to WHO, more than 3 billion people in the world are malnourished.
Common Diseases of Malnutrition
(i) Marasmus It is progressive deterioration caused by a diet low in total calories
and protein.
∑ Symptoms: Pronounced slowing of growth, extreme wasting of muscles.
∑ Remedy: Adequate diet.
BALANCED-DIET GUIDELINES FOR HEALTHY LIVING
Fig. 2.23 Food triangle for balanced diet

(ii) Kwashiorkor It is caused by protein deficiency.

∑ Symptoms: Fluid retention, swelling of abdomen, dry, brittle hair, mental
retardation and stunted growth.
∑ Remedy: Balanced diet.
(C) Overnourishment It is due to overconsumption of saturated (animal)
fats, sugar and salt in diet.
∑ Symptoms: Obesity, high blood pressure, diabetes, heart diseases, etc.
∑ Remedy: Balanced diet.
Overgrazing Animal grazing is a natural process of forage utilisation, because
herbivores produce in the environment where evolution formed them. When a plant
is grazed on severely, it uses energy stored in its roots to support regrowth. As this
energy is used, the roots die back. The dying of roots adds organic matter to the soil,
which increases soil porosity, the infiltration rate of water and the soil’s moisture-
holding capacity. After enough leaves have re-grown, the roots will regrow as well.
A plant is overgrazed when it is re-grazed before the roots recover. Overgrazing
reduces root growth by 90%. Pastures are less productive because there is less root
growth.
“Overgrazing can be defined as grazing plants (by livestock or wildlife) for
extended periods of time or without sufficient recovery periods.”
Impacts of overgrazing are listed below:
(i) Porosity of soil decreases.
(ii) The infiltration rate and moisture-holding capacity of soil decreases.
(iii) Soils have less organic matter and become less fertile.
(iv) Under the above adversed and undesirable conditions, desired plants become
stressed but the growth of thorny shrubs/poisonous plants may increase.
(v) Overgrazing destroys the vegetation completely. The entire land area
becomes prone to desertification and heavy soil erosion. This may cause
siltation of any river leading to severe floods that may claim a large number
of lives and property as well.
Notes:
1. Overgrazing is not a function of animal numbers. It is a function of time.
Even one cow in a big pasture will overgraze plants if she is kept there for a
longer duration or brought back too soon.
2. Worldwide, overgrazing is considered to be the major cause of soil
degradation.
3. A grassland is overgrazed where a linked vegetation changes and loss of
animal productivity arises from herbivores grazing of land.
Control Measures for Overgrazing Economic sustainability cannot be
achieved without environment sustainability. The latter requires that overgrazing
must be stopped. Cattle owners need to make sure that they do not bring the
animals before plants have recovered. When growth of plants is fast, recovery
periods of (4–16) weeks may be adequate. Thus, overgrazing can be stopped with
(Contd.)
(Contd.)
8–10 paddocks. Overgrazing will not occur if livestock are kept in a paddock for
less than 3 or 4 days. Awareness and some sort of legislation also help in stopping
overgrazing. Negative impacts of overgrazing can be prevented and /or reversed by
proper grassland-management practices.
2.6.2 Agriculture and Modern Agriculture

The word agriculture comes from the Latin words ager (meaning soil) and cultura
(meaning cultivation).
Agriculture means the cultivation of soil and or production of crop plants or
livestock products. It is synonymous with farming: the field-dependent production
of food, fodder, and industrial organic material.
The term modern agriculture depicts the push for innovation, stewardship and
advancements continually made by farmers to sustainably produce higher quality
products with a reduced environmental impact. It is based on the following:
(A) Agriculture Business and Marketing For solving the problem of
hunger, systematic and efficient marketing of foodgrains play an important role.
Poor cannot pay higher prices of foodgrains and they remain hungry. When
the marketing system is not efficient, profits earned from the consumers are not
adequately transferred to the producers. As a result, farmers do not get sufficient
price incentive to increase the production of food items which are in short supply.
To sum up, agricultural marketing plays a role in modern agriculture in fostering
and sustaining the willingness critical to rural and economic development.
(B) Organic Farming Organic farming is based on development of biological
diversity and the maintenance and replenishment of soil productivity through crop
rotation, use of animal and green manures, and some forms of biological control
of pests.
Chemical fertilisers are extensively used in intensive agriculture for increasing the
crop yields. But their use has spoiled the land, soil and water.
Table 2.10 Difference between intensive agriculture and organic farming
Objective Intensive Agriculture Organic Farming
(1) To increase crop yields ∑ Use of expensive inor- ∑ Use of economic manuers, farm
ganic fertilisers organic resources and biofertilisers
(2) To manage disease and ∑ Use of pesticides ∑ Use of Biological pest.
weed
(3) Effect on soil quality ∑ Soil quality gets reduced ∑ Soil quality improves.
Principles used in Organic Farming

(a) Nature does not use chemical fertilisers, pesticides and excessive water, but still
it provides the best food. Thus, nature is the best role model for farming.
(b) Soil must not be considered as an inert bowl to dump chemicals. Soil is a
living system.
(c) Living populations of microbes and other organisms present in the soil are
main contributors to fertility on a sustained basis. Thus, at all costs, they
must be protected and nurtured.
(d) From soil cover to soil structure, the total environment of the soil is more
important than any fertiliser we may wish to pump into it.
Fig. 2.24 Organic farming
(C) Sustainable Agriculture

“Sustainable agriculture means meeting the food needs of the present generation without
endangering the resource base for the future generation.”
Sustainable agriculture requires focus on soil, plant, agriculture, water and
nutrients through
(a) Conservation of soil and water to prevent degradation of soil productivity
and lengthening of crop
(b) Integrated plant protection for reducing the effects of intensive agriculture
(c) Efficient use of irrigation water to prevent problem of soil salinity, alkalinity,
etc.
(d) Integrated management of nutrients
Strategies for Sustainable Agriculture The following strategies are helpful
for sustainable agriculture
(a) Management of soil, water, nutrients, etc., by farmers
(b) Regulations, formulations and implementations of appropriate policies by
the government
(c) Use of right technologies for agriculture. It includes
∑ precision farming
∑ global positioning system, and
∑ animal feed-use efficiency.
(D) Conservation Tillage Conservation tillage is a farming process which
helps prevent land loss to erosion and water pollution. It also enhances carbon se-
questration.
(E) Integrated Crop Management

Integrated crop management is based
on agro-ecological principles. It in-
creases the yields of crop and reduces
the environmental damage.
Farmers are supported by educ-
ation and certification programmes. Fig. 2.25 Modern agriculture
This ensures that they apply right agricultural practices, with care and only when
required. They have the access to the technologies required to support modern
agriculture practices.
2.6.3 Effects of Agriculture or Environment

Humans get food from agricultural practices. However, the production, processing
and distribution of food changes the environment.
Agriculture has both on-site and off-site environmental effects. These are
summarised below:
Fig. 2.26 On-site and off-site environmental effects
Since the last few decades, the emphasis of most of chemical farms is exclusively on
productivity through high input in exchange for high returns and high productivity.
However, the following important considerations were overlooked:
(i) What Happens to the Land?
(a) The continuous use of artificial fertilisers, together with a lack of crop rotation,
reduces the soil’s fertility and this ultimately leads to land exhaustion.
(b) Where repeated deep ploughing were used to turn over the ground, heavy
rains carried away the top soil and left the ground useless for cultivation
through soil erosion.
(c) In areas that were intensively farmed (in conventional tillage) using tractors,
soil compaction problem was observed. Even a single tractor pass can compress
the surface enough to reduce the porosity of the soil.
(d) Large and chemical farms tend to be monocultures growing the same crop
and crop variety. This causes loss of cultivated biodiversity by 70%, increasing
surface run-off and therefore, soil erosion.
(ii) What Happens to the Environment?

(a) High crop-yield levels were produced by applying large quantities of artificial
fertilisers. Natural fertility of the soil was not maintained. About half of the
nitrate in the artificial fertilisers used in crops is dissolved by rain and irrigation
water. The dissolved nitrate runs off the fields to contaminate water resources.
(b) Animals (to be used in modern farms) are generally crowded together
indoors. Complex systems of machinery are needed to feed them. To prevent
disease, constant medication is also given. The cruelty to animals involved in
managing, breeding, growing and slaughtering is unimaginably horrifying.
Furthermore, with so many animals forced to live in small areas (indoor),
their waste accumulates at great speed. It is often poured into lagoons
which leak into local watercourses, contaminating them with disease- causing
pathogens and also contributing to algae-blooms.
(c) In places where stubble is burned, large amounts of potentially useful
organic matter disappears into the sky in clouds of polluting smoke causing
air pollution.
(d) The wild animals and plants which used to be around farms are deprived of
natural habitat. This habitat destruction leads to their death.
(iii) What Happens to Indigeneous Seeds and Plant Varieties?
Native animal breeds and cultivations lose out to hybrids and exotic species. Many
native animal breeds are threatened with extinction. Moreover, within the space of
one generation, many indigeneous seeds and plant varieties have disappeared.
(iv) What Happens to the People?
(a) The supply and trading in agricultural inputs and food is in the hands of a
few large corporations. This causes destruction of traditions and indigeneous
knowledge. As a result, food security is threatened and the importance of the
farmer and the consumer is reduced.
(b) Chemical agriculture is a threat to individual farmers and their livelihoods.
They are forced to change their lifestyle, unfortunately not for the better.
Fig. 2.27 How modern farming affects our world
Effects of Modern Agriculture Practices on Environment

(i) Detrimental Effects Increasing food demand, farming on environmentally
sensitive land, technological changes, economical changes, and need to have more
output per unit of land or labour (i.e. intensification of agriculture) has led to the
following environmental harms:
(a) Water pollution
(b) Air pollution
(c) Loss of wildlife, habitats and landscape features
(d) Soil degradation
(e) Water depletion
(ii) Environmental Benefits In some circumstances, the following benefits are
results of agricultural practices:
(a) Contribution to water accumulation and flood control
(b) Soil formation
(c) Nutrient recycling and fixation
(d) Carbon sequestration by trees and plants
(e) Wildlife protection
(f) Biodiversity protection
(g) Recreational provisions
(h) Aesthetic value provisions
2.6.4 Fertilisers and Associated Problems

Fertilisers are substances (natural or synthetic) that are added to the soil to restore
and enhance the soil fertility to improve the quality and quantity of plant growth.
All fertilisers contain variety of micronutrients and macronutrients (nitrogen,
phosphorus, and potassium). With proper application, these micro and macronu-
trients provide plants with the nutrients needed for healthy growth. However, im-
proper application can lead to a variety of problems associated with fertilisers.
(A) Fertiliser Problems
A brief description of fertiliser problems is given below:
(i) Fertiliser Burn An excess amount of fertiliser application causes fertiliser
burn. It is identified by leaf-tip burn, premature yellowing of foliage, and patch
discolouration,
∑ Leaf burn is due to overfertilisation, with symptoms appearing along the veins
and leaf margins.
∑ Discolouration is due to the excess salts in the soil resulting from overfertilisa-
tion. Plants are not able to absorb enough water for heathy growth due to excess
salts present in soil. This results in the yellow to brown appearance of tip burn.
By using the right amount of fertiliser (recommended for the specific plant),
fertiliser burn can be prevented.
(ii) Fertiliser Run-off Due to overfertilisation, fertiliser run-off happens which
can lead to a variety of environmental problems. For instance, phosphorus run-off
into lakes and other water courses causes an elevated growth of weeds and algae.
This unnatural growth of weeds and algae, saps oxygen from the water and threatens
aquatic life.
Eutrophication refers to a whole sequence of events, (illustrated in Fig. 2.28)

starting with nutrient enrichment and proceeding to the growth and die-off of
phytoplankton, the accumulation of detritus, the growth of bacteria, the depletion
of dissolved oxygen and suffocation of fish, shellfish, etc.
The increased nutrient level in the water will promote a rapid and heavy growth
of plants. Much of this plant life will be algae floating in the surface waters of the
river, lake or pond. Their rapid increase in numbers cause a thick mat or algal
bloom to spread across the surface of the water. This results in sunlight being cut off
and death of vegetation beneath these mats. The increase in dead matter provides
food for the bacteria which increase in numbers very rapidly, causing a rapid fall
in oxygen levels. The reduction in oxygen then leads to the death of fish and other
animals in the water.
OLIGOTROPHIC EUTROPHIC
Nutrient enrichment
∑ Less nutrients ∑ More nutrients
∑ Limited phytoplankton ∑ Rapid growth and die-off of phytoplankton
∑ Clear water allow enough ∑ Water turbidity

light to penetrate
∑ Accumulation of detritus
∑ Support the growth of Submerged
Aquatic Vegetation (SAV) ∑ Decomposers (mainly bacteria)feed on detritus
∑ SAV provides food, habitats and ∑ Bacteria (via respiration) consume oxygen,
dissolved oxygen to support so dissolved oxygen gets depleted
the rest of a diverse aquatic
ecosystem. ∑ Suffocation of higher organisms (like fish and shellfish)
∑ Water unappealing for boating,

sport-fishings, and swimming
∑ Some species of phytoplankton secrete various toxins

into water that may kill other aquatic life and injurious
to human health.
Fig. 2.28 Eutrophication
To prevent run-off problems from overfertilisation, soil tests must be done. It

helps in determining how much fertiliser needs to be added to soil.
(iii) Increased Pests In fertilisers, nitrogen is a primary macronutrient. It
promotes cell division, helps plants gain energy, and causes leafy, green foliage
growth. However, high nitrogen levels also results in increase in plant-damaging
pests. Too much nitrogen causes an immense amount of weak foliage. The foliage
growth may appear as healthy growth, but the thin cell walls make the plant
vulnerable to insects and disease. Insect damage is a leading threat to weak but thick
foliage as insects are attracted to foliage growth.
By using the right and recommended amount of nitrogen for the specific plant
grown, it is possible to prevent increased pests.
(iv) Soil Damage The use of synthetic fertilisers in soils without a balanced
addition of organic materials (which helps in formation of humus) leads to soil
compaction. As a result, the soil loses its nutrient and water-retention capacity
and is not able to make nitrogen readily available to the plants. As a consequence,
requirement for synthetic fertilisers increases, which continues to make the problems
worse. Gradually the soil becomes heavily mineralised and excessively susceptible to
erosion.
(v) Health Problems for People Excessive use of inorganic fertilisers and
resultant water pollution causes high consumption of nitrates through drinking
water and leafy vegetables. In the intestines, these nitrates are reduced to nitrites
by bacterial action. Nitrites, on reaching the bloodstream, become attached to
haemoglobin forming methaemoglobin. This reduces the oxygen-carrying capacity
of the blood and produces a condition known as methaemoglobin anaemia or the
blue baby disease, characterised by bluish colouration of the skin.
In adult humans, if nitrates are converted into amines and nitrosoaminess, it
causes gastric cancer.
(B) Solutions for Fertiliser Problems For avoiding problems associated
with fertilisers, the following guidelines are helpful:
(i) Use only a recommended amount of suitable fertiliser.
(ii) Do not apply fertilisers just before rain.
(iii) Use fertilisers at the minimum rate.
(iv) Poor aeration, wrong soil pH and diseases can all cause poor growth of plants.
Thus, if a plant grows poorly, it may not necessarily need more fertiliser.
(v) Use compost and other organic fertilisers for economically improving soil
texture and nutrient levels. Furthermore, organic fertilisers release nutrients
more slowly and leach into water supplies less.
(vi) Select and use the right fertiliser for a given crop based on fertiliser number
and apply it evenly.
Table 2.11 Fertiliser number
N P K
Fertiliser code 10 20 10
Weight (kg) of constituent (10/10) = 1 (20/10) = 2 (10/10 = 1)
Suppose you have a 10 kg bag of 10-20-10 fertiliser. It means, the fertiliser has
1 kg of nitrogen, 2 kg of phosphorus, and 1 kg of potassium. This is because fertiliser
number represents a ratio to inert matter. The first, second and third numbers tell us
how much N, P and K is in the fertiliser bag.
Nitrogen (N) is the chemical which makes plants have dark luscious green
colour. Nitrogen is required by chlorophyll which captures the sunlight in the
photosynthesis process for making oxygen, carbohydrates and energy. Nitrogen is

also used in reproduction. It also allows the plant to grow, produce more plant
leaves, and create a darker green colour.
Phosphorus (P) is in the form of phosphate. It helps in early maturement of plants.
As a result, flowering plants give flower early and of big size.
Potassium (K) helps in the development of healthy root system. The water dissolves
the nutrients in the soil and is absorbed by the root system. Thus, potassium gives
structure and strength to plant to sustain extreme weather conditions. Plants also
become drought resistant with the right amount of potassium
2.6.5 Pesticides and Associated Problems

Pest is any organism that causes an economic loss or damage to the physical well
being of human beings.
Pesticides are the chemical compounds that are used for killing of insects, rodents,
etc., stopping vital physiological processes within the organisms. The use of pesticides
help in increasing crop yields and in the eradication of diseases such as malaria.
Fig. 2.29 Basic groups of pesticides
(A) The Pesticide Treadmill The

term pesticide treadmill is used to describe
attempts to eradicate pests with synthetic
organic chemicals. However, these chemi-
cals do not eradicate the pests. Instead,
they increase resistance and secondary pest
outbreaks. This leads to the use of new
and larger quantities of chemicals, which
in turn lead to more resistance and more
secondary pest out-breaks, and so on. This
nonsustainable process is an unending
cycle constantly increasing contamination Fig. 2.30 Pesticide treadmill (as per
of foodstuff and ecosystems causing more late entomologist Robert
risks to humans (Fig. 2.30). Van den Bosch)
(B) Effects of Pesticides
The ecological fate of pesticides affects natural water supply, aquatic wildlife, insects
and birds. This is briefly discussed below:
(i) Water Supply Various streams and groundwater supplies, drained watershed
from agricultural, urban and mixed-use areas were found to contain pesticides. Even
those pesticides were found whose use has been banned. This is because pesticides
persist in the environment for longer times.
(ii) Aquatic Wildlife Pesticides are a potential cause of deformities and decline in
amphibians. Pesticides are present in many streams at concentrations that may have
effects on aquatic life or fish-eating wildlife.
(iii) Insects Pesticides are also responsible for dwindling populations of pollinator
species (bees) and beneficial insects. Colony Collapse Disorder (CCD) means the sudden
abandonment or evacuation of bee colonies through acute pesticide poisoning.
(iv) Birds Birds are environmental sentinels as they are much more sensitive to
pesticides than mammals. They forewarn us about the potential hazards to our
environment and our own health.
Pesticides affects birds indirectly by weakening them or reducing their food supply.
Birds may prey on target pests or nontarget beneficials treated with pesticides. This
leads to sudden exposure for a short period (acute) or prolonged exposure (chronic).
As a result, population of birds gets reduced.
(v) Humans The human body is susceptible to the effects of pesticides. Over
time, it can cause health problems.
(a) Endocrine System Problems When inhaled or absorbed through the skin,
the chemical structure of pesticides enable them to settle inside the fatty materials
contained in the body. As a result, pesticide residue can accumulate inside the body
gradually. The endocrine system of humans consists of chemical-hormone secreting
glands. Pesticides change the body’s normal hormone levels. As a consequence,
reproductive processes, cell growth and repair as well as cell-metabolism processes
are disrupted.
(b) Neurotoxicity In the human body, pesticides act on cholinesterase (an essential
neurotransmitter chemical in the brain and body tissue, it works in conjunction
with the body’s nerves and muscles). The body experiences a gradual decline in
nervous-system function, nausea, muscle weakness, and chronic fatigue because the
pesticide residues accumulate within body tissues.
Organophosphates and carbamate pesticides are responsible for chronic fatigue
syndrome and Parkinson’s disease.
(c) Cancer When cells become unable to regulate growth functions, they start
multiplying at abnormal rates resulting in cancer.
Accumulation of pesticides in the body causes abnormality in endocrine-system
processes. This abnormality greatly contributes to a breakdown in cell function.
Pesticide 2, 4 D is associated with a 50% increase in lymphoma disorder. Other
forms of cancer include lung, intestinal, prostate, brain and leukemia.
Risk = f (Hazard, Exposure)

∑ Risk (damage) by pesticide is determined by both toxicity (hazard) and the
likelihood of exposure.
A low level of exposure to a very toxic pesticide is less dangerous than a
high level of exposure to a relatively low toxic pesticide.
∑ As per WHO estimates, about 1 million pesticide-poisoning cases and
20,000 deaths occur every year globally due to high pesticide residues in
the food chain including fruits, vegetables, cereals, pulses, fishes, poultry,
meat products, water, milk (including mother’s milk) and milk products.
The rate of utilisation of pesticides is such that it contaminates soil, water
and food even in concentrations of parts per trillion to parts per million.
Table 2.12 Pesticides: Structure and uses

Major Structural Class Pesticides and its Structure Uses
(i) Chlorinated hydro- Broad spectrum—Peanut,
carbon soybean and cotton pests;
mosquito control (use banned
in some countries because it
accumulates in food chain,
cause adverse health effects
on wildlife and persists in the
environment)
(ii) Organophosphates Broad spectrum—Fruit and

vegetable pests, larvicide for
mosquitoes control
(iii) Carbamates Control of flies, mosquitoes,

ants and cockroaches
(iv) Chlorophenoxy Military defoliant, weed

acids control
(C) Solutions to Problems Created by Pesticides

(i) Limit the use of pesticide products.
(ii) Initiate crop rotation in farms and other management approaches.
(iii) Clean and use nonchemical traps to avoid home pests and thus avoid use of
pesticides. It helps in reducing your chances of getting cancer.
(iv) Support local initiatives to get a pesticide by-law enacted in your community
as quickly as possible.
(v) Before applying liquid pesticide, remove food, toys, etc. Close doors to
rooms that are not infested. Turn off central heating or cooling units. During
application, apply at low pressure to avoid making small particles that can
linger in the air. After application, open windows, turn on fans to speed up
drying time. Keep children and pets out of the treated area until the pesticide
has dried.
(vi) Use plant-based pesticides like neem-based insecticides which are eco-
friendly. It has pesticidal, antibacterial and antiviral properties and has been
developed in dust and spray forms for use.
(vii) Get complete toxicological information on the active ingredients of the
pesticide manufactured and only use if found right.
(viii) Pesticide manufacturers must obey standard specifications formulated by
competent authorities.
(D) Objectionable Properties of Chemical Pesticides
(i) Chemical pesticides have high physiological and ecological specificity.
(ii) Chemical pesticides are resistant to biochemical degradation.
(iii) There is an increase in concentration of pesticides in successively higher
trophic levels of a food chain or food web in a process known as bio-
magnification.
In an aquatic ecosystem, zooplankton consume pesticides and other organic
pollutants which may be consumed by the next trophic level (predators)
such as small fishes. These predators consume many prey organisms and
thus they accumulate and concentrate pesticides into a large extent. When
these predators are consumed by the next trophic level, these pesticides are
further concentrated and it goes on to successive trophic levels. Thus, there
is a magnification of pesticides in higher-trophic-level organisms.
Biomagnification also occurs in terrestrial ecosystems.
(iv) Chemical pesticides have the capacity for delayed onset of intoxication.
DDT Magnification of Trophic levels
concentration [DDT]
(ppm)
Fish-eating birds such as the bald
20 eagle, brown pelican and osprey
20 = 107
3 ¥ 10–6
2
2.0 = 106 Small fish
3 ¥ 10–6
2 ¥ 10–1 Zooplankton such as protozoa

2 ¥ 10–1 = 105
3 ¥ 10–6
4 ¥ 10–2 Phytoplankton such as algae

4 ¥ 10–2 = 104
3 ¥ 10–6
3 ¥ 10–6 Water
3 ¥ 10–6 3 ¥ 10–6
=1
Fig. 2.31 Biomagnification

(E) How to Get Rid of Pesticides from Fruits and Vegetables

Step (i) Rinse your fruits and vegetables in tap water briefly. The majority of
pesticide residue appear to reside on the surface of produce and is thus removed by
the mechanical action of rinsing.
Step (ii) For fruits like apples or pears that are easy to handle, spray with (i) one
per cent solution of dish liquid (i.e. detergent) and water (ii) 5% NaCl solution.
Then rub the solution over the surface of the item with your fingers.
Leafy green vegetables and broccoli tend to hold dirt in their crevices and it is
better to soak these often in a one per cent solution of dish liquid and water.
Step (iii) Rinse fruit or vegetable produce with tap water for about one minute.
This will remove any traces of dish liquid from your fruits and vegetables.
Step (iv) Normal household procedures, viz. peeling and cooking, are also very
effective.
2.6.6 Green Revolution

Green Revolution means better food-production methods or better agricultural practices
to secure the world food supply. It consists of crop-variety improvements, expansion
of irrigation and increased use of pesticides and fertilisers.
“The Green Revolution refers to the rapid increase in food production mainly through
the use of High-Yielding Varieties (HYVs) of seeds, chemical fertilisers, pesticides,
agriculture machinery and water.”
Impacts of Green Revolution Because of Green Revolution,
(i) Foodgrain prices have remain stable for the last 15 years
(ii) Food crisis has overcomed
(iii) Agricultural productivity has increased
2.6.7 Waterlogging
It means too much water in the root zone of a plant so that roots cannot absorb enough
oxygen to breathe. The result is the plant stops growing and within a few days, it may
die.
Causes
(i) Over-irrigation of soils
(ii) Farming on clayey soils; here water cannot move efficiently through the soil
and cannot be adequately drained; eventually waterlogging occurs
(iii) Excessive rain or flood, etc.
2.6.8 Salinity
It means accumulation of soluble salts in the soil due to over-irrigation. When excessive
quantities of soluble salts accumulate in the root zone, the crop has difficulty in
extracting enough water from the salty solution. It results in adverse crop productivity.
Fruit crops are the most sensitive to soil salinity followed by vegetables.
For the solution of this soil-salinity problem, root zone of the plants are flushed
with excess water. However, it may contaminate the groundwater or irrigation canals.
example 3 How has agriculture contributed to water pollution?

Solution
(a) Pesticide run-off from agricultural land impairs drinking-water quality. It
also harms water-based wildlife.
(b) Animal effluent from livestock and use of fertilisers in agriculture accounts
for higher nitrogen and phosphate emissions in surface water. It results in
eutrophication, which causes depletion of oxygen in water.
example 4 How has agriculture contributed to air pollution?

Solution In areas of intensive agricultural production, the following air-pollution
problems are encountered:
(a) Emissions of methane, nitrous oxide, etc., from agriculture contribute to
global warming and climate change.
(b) Offensive odours are produced by crop burning.
example 5 Why do agriculture practices cause loss of biodiversity?

Solution
(a) In countries where grasslands and wetlands are converted to cropland, several
rare species of wildlife have declined.
(b) Intensification of farming practices lead to habitat degeneration.
(c) Reduced crop rotations, increased fertiliser and pesticide application are
some of the main reasons for the loss of biodiversity.
example 6 How do agriculture practices cause soil erosion?

Solution
(a) The trees and plants hold the soil together. For agriculture, trees are removed
to create fields. Once the cover is gone; wind, rain, etc., start soil erosion.
(b) Animals (like cows, sheep, etc.) compact the ground due to their hooves. It
results in increased run-off of water, leading to soil erosion.
(c) Sheep also eat plants close to the ground, killing them and leaving the ground
prone to more wind/water erosion.
Case Studies
(i) Effects of Modern Agriculture on Punjab
Dr Rayed Tirado, from the University of Exeter, UK, conducted the study in
50 villages in Ludhiana, Bhatinda and Muktasar districts under a Greenpeace
Research Laboratories investigation in 2009. This study revealed radiation,
biological and chemical toxicity rampant in Punjab. As per WHO the safety
limit is 50 ppm w.r.t. nitrate levels in water. Twenty per cent of the sampled
wells showed nitrate levels above this safety limit. The study connected it with
high use of synthetic fertilisers. High nitrate levels in drinking water can be
harmful to humans particularly for infants under 6 months where it is linked
to methemoglobinemia or blue-baby syndrome. With increasing poisoning of
the soil, the region once hailed as the home to the Green Revolution, now is
being termed as the “Other Bhopal” due to excessive use of chemical fertilisers.
A comprehensive study conducted by Post Graduate Institute of Medical
Education and Research (PGIMER) has underlined the direct relationship
between indiscriminate use of fertiliser and pesticides and increased incidence
of cancer in several villages of Punjab including Khara, Bhimawali, Puckka,
Koharwala, Jhariwala, etc.
(ii) Waterlogging in India
2,189.4 ha have been reported to suffer from waterlogging in irrigation canal
commands in India. The increased level of the water table can lead to reduced
agricultural production. Stagnant water tables at the soil surface are known to
increase the incidence of waterborne diseases like dengue, malaria, etc.
(iii) Salinity in India
3,469.1 ha were reported to be seriously salt affected in India. Salinity induced
by human activity is a desertification problem of increasing world concern as
pressure increases on agricultural land for food production.
2.7 ENERGY RESOURCES

2.7.1 Growing Energy Needs (Energy Scenario in India)
Energy is essential for economic growth and sustenance of modern economy.
(A) Energy Import India, though rich in coal and abundantly endowed with
renewable energy in the form of hydro, wind, solar and bio-energy, has very small
hydrocarbon reserves. India is a net importer of energy, more than 25% of primary
energy needs being met through imports mainly in the form of natural gas and
crude oil.
(B) Energy Production Pattern Coal and oil account for 54% and 34%
respectively, with natural gas, hydro, solar and nuclear contributing to the balance.
Nearly 62% of power generation is from coal-fired thermal power plants and 70% of
the coal produced every year in India has been used for thermal power generation.
(C) Distribution of Primary Commercial Energy Resources The
distribution is non-uniform. The northern and north-eastern regions account for
70% of the total hydro potential, whereas the eastern region accounts for about
70% of the total coal reserves in India. The southern region has most of the lignite
deposits in the country.
(D) Energy-Consumption Pattern The industrial sector consumes about

52% of commercial energy production. The energy consumption per unit of
GDP (energy intensity) is one of the highest in comparison to other developed and
developing countries. Thus, there is a huge scope for energy conservation in India.
(E) Future The long-term availability of energy from sources that are affordable,
accessible and environmentally friendly will govern the future economic growth in
India.
(F) Over-exploitation of Energy Resource in India Power demand in
India touched an all-time high of 99,027 MW recently, a year-on-year growth of
over 16%. In our country, economic growth is very fast which is responsible for the
growing energy demands of the country.
India’s demand for energy is set to increase to as much as 315,000 MW by 2017
at an average GDP growth rate of 8% per year as per the forecast from Mckinsey
and company in 2008. To meet this energy requirement, the country has to over-
exploit all its energy resources.
Presently the power needs of the country are primarily met by thermal power
stations (about 60%), followed by hydro, wind and nuclear power stations.
India is experiencing shortages in the production of domestic coal. Many of the
thermal power stations, including NTPC, faced critical coal stock levels and had to
cut down their production levels. The obvious result was power cut. In 2008–09
due to non-availability of power, India Inc. has supposedly lost `43,205 crore as per
a study. The coal reserves of India may get exhausted by 2040 at the current rate of
coal consumption. India may have to depend entirely on coal imports.
(G) Relationship Between Energy Resources and Development in
India About 60 years back, at the time of independence, the installed power
generation capacity was 1300 megawatt, (MW). In 2009, power demand in India
touched 99,027 MW.
As on 31st march 2005, the installed power-generation capacity using various
methods is tabulated below:
The installed power generation capacity
Thermal 80,902.45 MW
Hydro 30935.63 MW
Wind 13065.37 MW (as on 31st Dec. 2010)
Nuclear 2770 MW
Energy is the key input to drive and improve lifestyles. Improvement in the
living standards, industrialisation, education, health-care services, etc., all depend
on availability of energy. Availability of energy, energy resources and consumption
of energy all directly govern the progress of the country.
(H) Problems due to Over-exploitation of Energy In the US, non-
renewable fossil fuels provide 92% of the energy used. The US has 3% of the world’s
oil and petroleum resources, but consumes 25% of the crude oil extracted in the
world. US citizens also waste tremendous amount of energy. Higher consumption
of energy resources means larger emissions of greenhouse gases which lead to global
warming and consequent problems.
Many developing countries are striving to reach the level of prosperity of the US.
It has been estimated that if world starts consuming at the same rate as the US, the
world could run out of fossil fuels in a few years.
Fig. 2.32 Problems due to over-exploitation of energy resources
2.7.2 Types of Energy

Energy is the ability to do work.
Broadly, there are six types of energies, viz. mechanical, radiant, chemical, heat,
electrical and nuclear. Mr CHEN is a mnemonic for remembering the six forms of
energy.
Fig. 2.33 Interconversion of different types of energies

The different types of energies are briefly described below:

(i) Mechanical Energy Energy due to an object’s motion (kinetic) or position
(potential) is known as mechanical energy.
Examples Windmill used to make electricity, water wheel used to grind grain.
(ii) Radiant Energy Radiant energy is electromagnetic energy. It includes energy
from gamma rays, X-rays, ultraviolet rays, visible light, infrared rays, microwaves
and radio waves.
Examples Solar panel used to provide electricity and heat for a house; microwave
oven used for cooking.
(iii) Chemical Energy Energy that is available for release from chemical reactions
is termed chemical energy.
Examples Gasoline is used to run a car.
(iv) Heat Energy The heat energy of an object determines how active its atoms
are.
Examples Coal was used to produce steam for steam engines of trains.
(v) Electrical Energy Energy caused by the movement of electrons is called
electrical energy.
Examples Electricity is used to run appliances in our homes.
(vi) Nuclear Energy Nuclear energy is the energy stored in the nucleus of an
atom. It is the energy that holds the nucleus together. It is released when the nuclei
are combined (nuclear fusion) or split apart (nuclear fission).
Example A nuclear power plant uses the fission of atoms to create energy that is
converted into electricity.
According to the first law of thermodynamics, “Energy is never created nor
destroyed, but it can be converted from one type into another.”
Electromagnetic Radiation
Electromagnetic waves are produced by the motion of electrically charged particles.
These waves are also called “electromagnetic radiation” because they radiate from
electrically charged particles. They travel through air, empty space and other
substances. The electromagnetic radiation travels at 3 ¥ 108 m/s in vacuum.
(i) Examples of Electromagnetic Radiation AM and FM radio waves, TV
signals, cell phone communication links, microwaves, infrared radiation, light,
X-rays, gamma rays.
(ii) Uses of Electromagnetic Waves
(a) One-way and two-way communication systems
(b) Radar
(c) Cooking (with microwaves)
(d) Medical imaging (X rays)
(e) Night vision (infrared)
(f) Astronomy (radio, gamma, UV, visible, IR, microwave)
All that we experience through our eyes is conveyed by electromagnetic radiation.

Table 2.13 Types of electromagnetic radiation
Non-ionising Radiations Ionising Radiations
(i) They are low-energy radiations (i) They are high-energy radiations
(ii) Overexposure causes skin burns (ii) Overexposure causes genetic mutation
or alteration in cellular structure
(iii) Examples: Visible and infra-red radia- (iii) Examples: X-rays, Gamma rays
tion, radio and microwaves
2.7.3 Renewable and Nonrenewable Energy Sources

(A) Conventional and Nonconventional Sources of Energy
Conventional energy sources are energy sources which are nonrenewable. However,
nonconventional energy sources are energy sources which are renewable and ecologically
safe (Fig. 2.34).
Fig. 2.34 Important energy sources

The important differences between conventional and nonconventional sources
of energies are summarised below:
Table 2.14 Differences between conventional and nonconventional sources
of energies
Conventional Sources of Energy Nonconventional Sources of Energy
(i) They are fully developed. (i)They are still undergoing development.
(ii) They use nonrenewable resources. (ii)They use renewable resources.
(iii) Inexpensive. (iii)Expensive.
(iv) Require established technologies. (iv) Require new technologies which are still
under research and development.
(v) Ecologically not safe for usage. (v) Ecologically safe to use.
(vi) Available in limited quantity. (vi) Available in plenty.
(Contd.)
(Contd.)
(vii) Carbon and other greenhouse gas emis- (vii) Free from such problems.
sions from the combustion of coal, natu-
ral gas, etc., are known to have disastrous
environmental and health consequences.
These gases are also major culprit in
climate change.
(viii) Examples: Petroleum, coal, etc. (viii) Examples: Solar, wind and hydropower, etc.
(B) Renewable Energy Programmes in India Major thrust is given to-

wards research, development, demonstration, commercialisation and deployment of
(i) New and renewable energy system/devices for transportation
(ii) Portable and stationary applications for rural, urban, industrial and
commercial areas
(iii) Alternate fuels for surface transportation including electric/hydrogen/hybrid
vehicles
(iv) Biofuel for motive power for stationary/portable applications
(v) Hydrogen energy
(vi) Cowdung based power plants (the new component in the biogas programme)
The above-mentioned new thrusts are being given to renewable energy
programme in India to closely align them with the objectives of the common
minimum programme regarding rural electrification, energy security and world-
class infrastructure.
2.7.4 Hydro-Power Energy or Hydroelectric Energy

Hydroelectricity or hydroelectric power is the electricity obtained by harnessing the power
of water flowing down from a high level.
It is a renewable, affordable and pollution-free source of energy.
Major Purposes of Dams
Dams are used for storing water. This
stored water is led down through
large pipes or tunnels to lower levels.
In the course of the fall of water, the
water rotates turbines. The produced
mechanical energy is converted
to electricity by the generators
connected to it. Transformers change
the alternating current produced by
the generators into currents of very
high voltage for easy transmission Fig. 2.35 Generation of hydro-electric
through long distances (Fig. 2.35). energy using a dam
(i) Advantages
(a) Economical The cost of operating a hydroelectric plant is nearly immune
to increases in the cost of fossil fuels. Operating labour cost is also low.
(b) Safe Hydroelectricity produces the least amount of greenhouse gases.
(ii) Disadvantages
(a) Failure Hazard In the case of failure of dams, millions of people become
homeless, sick and even die.
(b) Limited Service Life As rivers convey silt, higher the siltation, lower will
be the service life of dam.
(c) Environmental Damage Dams are responsible for habitat fragmentation,
aquatic ecosystem disruption, and greenhouse-gas emissions.
(d) Population Relocation Problem Millions of people need relocation and
generally they do not get necessary compensation.
(e) Energy Production is Affected by Amount of River Flow Specially during
drought period, hydroelectric power cannot be generated.
2.7.5 Fossil Fuels

Petroleum and coal are formed from the fossilised remains of animals and plants,
hence they are known as fossil fuels. As they are used up much more rapidly than
they are replenished by nature, it might ultimately result in fuel shortage.
(A) Coal
Coal is defined as stratified rock, consisting of organic matter of fuel value derived
from the partial decay and alteration of accumulated plant materials by the action of
heat and pressure over millions of years.
Coal is of the following four types:
Fig. 2.36 Types of coal
(i) Advantages The factors which are in fovour of usage of coals in huge tonnage
quantities are availability, low cost, least risk of fire hazards and easy storage.
(ii) Disadvantages
(a) Combustion of coal is a slow process.
(b) Combustion control is not easy.
(c) After combustion, ash is always produced and so its disposal is a problem.
Smoke is also invariably produced.
(d) Use of coal in internal combustion engines is not possible.
(e) Calorific value and thermal efficiency is least.
(B) Coal-based Thermal Power Plants (Environmental Problem)

About 80% of domestic reserves of coal in India are characterised by ash content
of 35% to 45%. Burning of this inferior-quality coal results in lesser efficiency and
higher emissions of pollutant gases including CO2, SOx and NOx. It also releases
particulate matter, bottom ash and fly ash. Coal mining which is done to extract coal
to feed into thermal plants is also hazardous. The environmental problems caused by
mining and burning of coal are endless. A few of these are summarised below:
(i) Carbon Dioxide (CO2) Coal-based thermal power plants are the major
contributor of CO2 (a greenhouse gas) responsible for global warming.
(ii) Sulphur Dioxide (SO2) Depending on the type and rank of coal, sulphur in
coal ranges from 0.1–3.5 %. During combustion of coal in thermal power plants,
sulphur combines with oxygen to from SO2.. Thermal power plants are the largest
emitters of SO2. In atmospheric air, SO2 is converted into sulphuric acid. It can
precipitate down as acid rain leading to destruction of ecosystems.
(iii) Oxides of Nitrogen (NOx) Coal-based thermal power plants are the second
largest emitter of NOx which combine with water to form HNO3. It is responsible
for acid rain, smog and ground ozone. NOx is a hazardous pollutant and is respon-
sible for visual and respiratory problems.
(iv) Particulate Matter Although there are arrangements in thermal power
plants to collect the ash, still some ash goes out through the stack and is known as
particulate matter emission. The particulate matter are dispersed over a very wide
area from very tall stacks of thermal power plants. The particles of size less than 2.5
microns (called PM 2.5) are of great concern as they are responsible for respiratory
illnesses in humans.
(v) Ash In coal-based thermal power plants, the residue left after the combustion
process is know as ash.
A 500 MW coal-fired thermal power plant burning coal with around 20% ash
results in the accumulation of 2 million tons of ash in 5 years. A small portion of
this ash may be utilised by cement plants but disposing the bulk of it on a long-term
basis can raise major environmental issues. The ash particles can be carried away to
surrounding areas though wind. Toxic elements of ash can percolate into the water
system causing harm to vegetation and humans.
(C) Petroleum
The word petroleum is derived from Latin petra which means rock and oleum which
means oil.
Petroleum is a complex mixture of paraffinic, olefinic and aromatic hydrocarbons
with small quantities of organic compounds containing oxygen, nitrogen and
sulphur. It is also called mineral oil because it occurs beneath the earth. Petroleum
refining of crude oil or petroleum provides many liquid fuels that are in current use.
A brief description of important liquid fuels, viz. gasoline, diesel and kerosene oil is
given on next page.
(i) Gasoline or Petrol It is a mixture of hydrocarbons from pentane to octane. It

is highly volatile and inflammable. It is used as a fuel for internal combustion engines.
Its calorific value is about 11,250 cal/g.
(ii) Diesel Oil It is a mixture of higher hydrocarbons (C15 to C18). It is used as a
fuel for diesel engines and its calorific value is about 11,000 cal/g.
(iii) Kerosene Oil It is a mixture of hydrocarbons (C10 to C16). Its calorific value
is about 11,100 cal/g. It is used as domestic fuel in stoves.
(D) Gaseous Fuels
(i) Natural Gas It is obtained from wells dug in the oil-bearing regions. It is
mainly composed of methane, ethane and other hydrocarbons. It is also called marsh
gas because it mainly consists of methane (about 88.5%). It is used as a domestic
and industrial fuel, because of its high calorific value (8000–14000 kcal/m3).
(ii) Compressed Natural Gas (CNG) The natural gas compressed at very high
pressure of about 1000 atmosphere is called CNG. The calorific value of CNG
is 31400–37700 kJ/m3. The use of CNG as a fuel for automobiles has reduced
pollution in urban cities. As it undergoes complete combustion in CNG engine so
there is nil possibility of release of CO in the atmosphere. Further, CNG is much
safer fuel with lower operating cost.
(iii) Liquified Petroleum Gas (LPG) The main constituents of LPG are
n-butane, isobutane, butylene and propane. The calorific value of LPG is about
27,800 kcal/m3. It is mainly used as domestic fuel. To help in the detection of gas
leakage, a strong-smelling substance, viz. ethyl mercaptan, is added to the LPG gas
cylinders. LPG is also used as motor fuel because it easily mixes with air and burns
cleanly without residue and without knocking.
2.7.6 Nuclear Energy

The study of nuclear fuel is important because energy changes involved are many
million times greater than in chemical fuels. The source of energy in nuclear fuel is
nuclear fission or nuclear fusion reaction. These are discussed below.
(A) Nuclear Fission When an unstable nucleus of a heavy atom (like ura-
nium–235) is bombarded with neutrons, the former splits up into two medium
weight nuclei with the liberation of an enormous amount of energy.
235 1 Fission
92 U + 0 n æææÆ 139
56 Ba +
94
36 Kr + 3 01 n + Energy
In all fission reactions, more neutrons are emitted than consumed. They, in turn,
are capable of fission of more heavy atoms and a chain reaction is started. When
this chain reaction is controlled, it can lead to power generation in a device called a
nuclear reactor.
(B) Nuclear Fusion When two lighter nuclei (like deuterium atoms) are heat-
ed to a very high temperature (~106°C), they fuse together to form a heavy, more
stable nucleus and an enormous amount of energy is liberated.
2 2 Fusion 4
1 H + 1 H æææÆ 2 He + Energy
High temperatures needed for fusion can be attained by using the heat evolved
in a fission reaction. But, in this way, the fusion of hydrogen gets out of controlled
and leads to explosion (hydrogen bomb).
(C) Merits and Demerits of Nuclear Energy
(i) Merits of Nuclear Energy
(a) Availability Nuclear power plants could still produce electricity after coal and
oil become scarce.
(b) Less Fuel Requirement One ton of uranium produces more energy than is
produce by several million tons of coal or several million barrels of oil.
(c) Less Pollution Well-operated nuclear power plants do not release contaminants
into the environment. As combustion is not done so no CO2, SOx, NOx, are released.
Thus, there is very little effect on environment.
(d) Economical Cost of fuel is a much smaller percentage of the total cost and
operating cost is about the same as coal-based thermal power plant. Generation of
power is less susceptible to price fluctuations. One fuel pellet about the size of a
pencil eraser produces the same energy as about 1 ton of coal, and after reprocessing
2/3rd amount can be reclaimed.
(e) Employment Energy generation from nuclear power plants creates high
paying, skilled jobs.
(f) Safe Safety record of nuclear power plants in the world is fantastic.
(g) Reliable Nuclear power plants have very high capacity factors. Presently, 12%
to 18% of the world’s electricity is generated through nuclear energy.
(ii) Demerits of Nuclear Energy
(a) Large Initial Cost To develop a single nuclear power plant about 15 years to
20 years are required along with expenditure of huge amount of money. The nuclear
reactors will work only as long as uranium is available.
(b) Dangerous Waste The waste produced after fission reactions of uranium
consist mainly of unstable, radioactive elements. It is very dangerous to the human
health and environment for thousands of years. It needs professional handling and
careful storage isolated from the living environments. In 1957, at a dump site in
Russia’s Ural mountains, dozens of people were killed by the mysterious explosion
of buried nuclear waste.
(c) Less Life of Nuclear Reactors They could only last for about 40 years to 50
years.
(d) Chances of Worse Disasters Meltdown is one possible type of reactor disaster
in which the fission reaction goes out of control, leading to nuclear explosion and
the emission of great amount of radiation. In the Chernobyl nuclear power plant in
Ukraine, a large amount of radiation escaped from the reactor in 1986. Hundreds
of thousands of people were exposed to radiation, resulting in deaths of several
dozens of peoples within a few days. Radiation-induced cancer resulted in deaths of
thousands of more people. One cannot deny the possibility of repetition of such disasters
in future.
(e) Domestic unavailability of safe storage and reprocessing facilities.
(f) Fear security concerns, terrorism and proliferation of nuclear weapons. They are a
major threat to the world as they cause large-scale devastation.
(D) Major Concerns Regarding Use of Nuclear Power for Electricity
Generation in India
A brief description of the above is given below:
(i) Deficiency of Uranium The Department of Atomic Energy (DAE) has
formulated an approach for the nuclear energy resource consisting of the following
three stages;
(a) Setting up of natural uranium fuelled Pressurized Heavy Water Reactors
(PHWRs): India has achieved maturity for this.
(b) Setting up of fast breeder reactor utilising a uranium–plutonium fuel cycle.
The beginning was made in 2003 through commencement of construction.
(c) Setting up of breeder reactors utilising thorium fuel. India’s thorium reserves,
about 2.9 lakh metric tons, are the second largest in the world.
(ii) Absence of Self-sufficiency India’s civil nuclear strategy has been directed
towards complete independence in the nuclear fuel cycle. This self-sufficiency
extends from uranium exploration and mining though fuel fabrication, heavy water
production, reactor design and construction, to reprocessing and management.
(iii) Small Contribution of Nuclear Energy to India’s Energy Mix The
nuclear establishment in India has failed to deliver what the pro-nuclear lobby had
promised nearly 60 years after its inception.
(iv) Environmental Concerns Regarding Digging of Uranium Mines India
has only modest reserves of about 70,000 metric tons of uranium which may never
be fully exploited because environmental consideration will not allow the miners to
dig new uranium mines. Public protests against Uranium Corporation of India Ltd
(UCIL) have prevented mining of uranium since 1985.
(v) Safety Concerns India still faces severe challenges regarding the operational
safety of uranium mines, nuclear power stations, etc.
There are also serious problems to do with treating and disposing of the large
volumes of highly radioactive wastes.
Terrorist attacks put additional tremendous pressure on nuclear reactor safety.
Case Study
Jaitpur Nuclear Power Project
India has 20 nuclear reactors in operation generating 4780 MW nuclear power
as of 2010. To generate additional nuclear power, seven other reactors are under
construction. On the plains of Jaitpur, 420 km south of Mumbai, a six-reactor
nuclear power complex is planned. If built, it would be one of the world’s largest
nuclear power complexes. In the wake of Japan’s Fukushima nuclear accidents,
environmentalists, fishermen and local farmers have been protesting over this
project. This is because of the following reasons.
(i) To build the reactors, 931 hectares of farmland will be needed. This land is
now home to 10,000 people, their main orchards, rice fields and cashew trees.
(ii) Livelihoods of fishermen in the region will be taken away.
(iii) Marine life will be adversely affected through the release of waste water
from the plant into the sea.
(iv) The survival of the fishermen and local farmers will be very difficult.
(Hindustan Times 27/11/2000, Sydney morning Heralds 23/4/2011)
2.7.7 Solar Energy

Solar energy is the energy received by the earth from the sun that is converted into
thermal or electrical energy. Solar energy influences the earth’s climate and weather
and sustains life. Although solar energy only provides 0.15% of the world’s power,
experts believe that sunlight has the potential to supply 5000 times as much energy
as the world currently consumes.
Broadly speaking, solar energy is a term for describing a range of methods for
obtaining energy from the sun. For instance, wind, biomass and hydropower are
all forms of solar energy. Wind
develops through lows and highs
in temperature. Wind drives waves.
Rainfall, created by sun-warmed
evaporated water feeds the rivers that
are sources of hydro power. Fossil
fuels are also forms of stored solar
energy. Coal, oil and gas formed
hundreds of millions of years ago
from decomposed plant matter, plant Fig. 2.37 Technologies and applications
matter that grew by aid of the sun. of solar energy
(A) Applications of Solar Energy in Modern Days Some of the impor-
tant applications of solar energy are summarised below:
(i) Space cooling and heating through solar architecture
(ii) Potable water via distillation and disinfection
(iii) Solar cooking
(iv) Solar hot water
(v) Day lighting

(vi) High-temperature process heat for industrial purposes
(vii) Solar air-conditioning
(viii) Solar desalination
(ix) Solar electricity–photovoltaic
(x) Solar electricity–thermal
(xi) Solar vehicles
(xii) Solar chimney
(B) Advantages and Disadvantages of Solar Energy
The advantages of solar energy are cost-effectivity, renewability, installation ease,
low maintenance, pollution free. These are briefly discussed below:
(i) Cost-effectivity If you use a solar power system to reduce electric
consumption from traditional power companies, the savings will be reflected
in reduced electric bills.
(ii) Renewable Resource Solar power can be regenerated and replenished
without fear of depletion because the sun is used as the energy source.
(iii) Easy Installation and Use of Solar Powered Products Solar panels, hot-
water heaters, lighting, fountains, pumps, etc., are easy to install and/or use.
(iv) Long Life and Low Maintenance The life of solar panels is long (≥25
years) and maintenance free. Maintenance only requires that solar panels are
kept dirt-free and snow-free for maximum contact with sunlight.
(v) Pollution Free Solar power energy is eco-friendly as solar energy does not
pollute the air or produce greenhouse gases like traditional energy sources.
The disadvantages of solar energy are summarised below:
(i) As solar power uses the sun to produce electricity, generally, solar power
cannot be created at night, during a cloudy day when sunlight is diminished
or during a rainy seasons.
(ii) The initial cost of installation of solar panels is high.
(iii) Efficient collection of solar energy is a big challenge because solar radiations
falls over a vast area in a scattered manner.
(iv) Solar cooking takes more time
and all sorts of food cannot be
cooked in a solar cooker, for
example, the ‘chapatti’.
(C) Use of Solar Energy for
Space Heating of Buildings
The architectural design of buildings
helps in their passive space heating using
solar energy. Following strategies are
useful for passive space heating:
(i) Provide large south-facing win-
Fig. 2.38 Passive solar design technique
dows (Fig. 2.38).
(ii) Provide an entire wall of double-glazed windows.

(iii) Provide a heavy dark-coloured south-facing wall behind a layer of glass, with
room air circulating by convection between the wall and the glass.
(iv) Provide a flat roof covered by a pond of water. Provision should be made for
an insulating screen cover for cooling requirements in summer.
Note that no mechanical equipment is needed for passive solar heating.
An active technology of solar space heating needs a collector to absorb and collect
solar radiation. Subsequently, fans or pumps are used to circulate the needed air or
heat-absorbing fluid (generally water). Water systems are more common than air
systems as they offer better heat-exchanger performance.
(D) Use of Solar Energy for Generation of Electricity–Photovoltaics
Photovoltaics (PVs) are arrays of cells containing a solar photovoltaic material that
converts solar radiation into direct current electricity. Solar cells produce direct
current (dc) electricity from sunlight, which can be used to power bulb/equipment
or to recharge a battery [Fig. 2.39]. However, for grid-connected power generation,
an inverter is required to convert the dc to alternating current (ac):
Fig. 2.39 Use of solar energy for the generation of electricity

A number of solar cells, electrically connected to each other and mounted in a
support structure or frame, is called a photovoltaic module. Multiple modules can be
wired together to form an array. In general, the larger the area of a module or array,
the more electricity that will be produced.
When n-type and p-type semiconductors are sandwiched together and irradiated
with sunlight, the excess electrons in the n-type material flow to the p-type, and
the holes thereby vacated during this process flow to the n-type. Through this hole
and electron flow, the two semiconductors act as a cell, creating an electric field at
the surface where they meet (known as p-n junction). It is this field that causes the
electrons to jump from the semiconductor out toward the surface and make them
available for the electrical circuit [Fig. 2.39].
(i) Advantages of Solar Photovoltaics
(a) Easy installation and maintenance
(b) Pollution free
(c) Long life
(d) Viable for remote and isolated areas, forest, hilly, desert regions
(ii) Disadvantages of Solar Photovoltaics The high initial cost, specially of
the silicon wafer is the major constraint in the widespread use of solar cells.
(iii) Applications of Photovoltaic Cells and Solar Panels Photovoltaic cells
are used in watches, pocket calculators and toys. Solar panels are useful to light up a
house, run an irrigation pump, operate traffic lights, etc.
(E) Solar Water Heater Solar water heater consists of a flat-plate collector,
with a black bottom, a glass top, and water tubes in between. The collector is placed
at a suitable angle to catch the sun’s energy. The black bottom of the collector gets
hot by absorbing solar radiation. The heat warms up the water in the tubes. The
insulated storage tank is placed above the collector, the cool water moves down into
the tubes and the water moves into the tank by natural convection.
Fig. 2.40 Active solar water heater system
As the energy is coming from the sun, utility bills are much lower and within a
few years the installation cost is recovered.
2.7.8 Biomass
The term biomass is used for the dead plants and trees (e.g. wood, crop residue, etc.)
and the waste material of living organisms (e.g. cattle dung, sewage, etc.). Biomass
energy or bioconversion means the direct burning of waste paper, wood, cattle dung
or converting them to a fuel.
The various ways of using biomass as a fuel:
(i) Biomass can be directly used as a fuel.
Example Burning of biomass like cattle dung in chulhas.
(ii) The biomass is first converted into a fuel and then these fuels are used for
heating purposes, more effectively.
Example Conversion of cattle dung into biogas.
2.7.9 Biogas and Biofuel (or Green Fuel)

(A) Biogas Biogas consists mainly of methane. It burns with a blue flame and
its average calorific value is about 5300 kcal/m3.
Gobar gas is the cheapest and most easily available biogas. It is made in a gobar-
gas plant. Cattle dung is mixed with water (in equal parts) to form a slurry. It
is then poured in a ‘well’ constructed of a masonry work (i.e. ‘digester’). There
anaerobic fermentation occurs at 34–48°C. The gas generated due to continuous
decay is mostly methane (Fig. 2.41) and is collected in a gas holder. One kg of
dung generates 160 litres of biogas and 164.6 kcal of extra heat is generated by this
indirect burning.
Fig. 2.41 Gobar-gas plant

(i) Advantages
(a) More heat is generated by burning gobar gas instead of cattle dung.
(b) It is free from smoke, dust, dirt, etc. Thus, the environment and utensils
remain comparatively clean.
(c) In addition to cattle dung, a gobar-gas plant can also digest human refuge,
poultry, etc. Thus, production of gobar gas means optimum utilisation of
waste.
(ii) Limitation Gobar gas should be used within 10 metres of the gobar-gas plant.
(iii) Applications
(a) Biogas is used as domestic fuel in many villages.
(b) Biogas is also used for lighting purposes.
(c) A biogas plant also simultaneously gives good quantity of excellent manure.
This manure has 2% nitrogen content as against 0.75% in farmyard
manure.
(B) Green Fuel “Green fuel (or biofuel) is a type of fuel obtained from nonfood
sources like green algae which is more environmental friendly than the widely used
and quickly disappearing fossil fuels.’’
In recent years, the processing of sugar and starch plants into ethanol has come
under heavy criticism because
(i) This results in food shortages
(ii) The fermentation process causes air pollution
(iii) The obtained fuel on combustion may emit formaldehyde, ozone, and other
carcinogenic substances
(iv) One acre of corn produces 200 times less oil as can be obtained from one
acre of algae
Case Study
The Central Salt and Marine Chemicals Research Institute (CSMCRI) has
become the first Indian body to successfully produce ethanol from a seaweed,
Kappaphycus alvarezii, in the year 2010.
Scientists of CSMCRI drove an ambassador car with a fuel blend of 10 %
ethanol and 90 % petrol in a major ecofriendly step towards renewable energy
generation and use in India.
CSMCRI plans for mass-scale production of ethanol in three years through
offshore cultivation on a five-hectare area on the Tamil Nadu coast with the
following major advantages.
(i) No pressure on agricultural land.
(ii) No requirement of fresh water, fertiliser and pesticides for irrigation.
(iii) Seaweed processing also produces sap (a biofertiliser especially used for
sugarcane crop)
2.7.10 Hydrogen as an Alternative Future Source of Energy

Hydrogen is a very light gas, and its density is eight times less than that of natural
gas. There are no significant problems with regard to storage, transportation,
dispensation as well as end use of hydrogen.
Hydrogen is either produced through the steam reformation of natural gas
or through electrolysis of water with renewable energies such as solar, wind and
geothermal.
By burning fossil fuels, more than 90% of the world’s energy requirements are met.
This leads to emissions of carbon dioxide, which is responsible for the greenhouse
effect and therefore responsible for the warming of our planet. Global warming
at accelerated rates is inevitable if we do not reduce the emission of greenhouse
gases. A hydrogen-based transport system has the potential to play an important
role in reducing greenhouse gas emissions. To propel vehicles, the hydrogen can be
burnt directly in either Internal Combustion Engines (ICEs) or used as a fuel for
producing electricity in fuel cells. The electricity is produced by an electrochemical
reaction. The electric power is then used to power an electric motor in the vehicle.
Fuel-cell driven vehicles have great potential to be more efficient and ecofriendly
than conventional fuel-driven vehicles. The vehicles will emit only steam but no
greenhouse gas.
Hydrogen is considered a secondary source of energy (or energy carrier).
Electricity is also an energy carrier. They are used to move, store and deliver energy
in a form that can be easily used.
(A) Advantages of Hydrogen as an Important Energy Carrier in the
Future
(i) Pollution free Hydrogen is a pollution free fuel.
(ii) Economical It is less costly to ship hydrogen by pipeline than sending
electricity over long distances by wire in some instances.
(iii) Various Applications It can be used for transportation, heating and power
generation in places where it is difficult to use electricity.
(iv) Easy Storage A large volume of hydrogen can be easily stored in a number
of different ways.
(v) High Efficiency Hydrogen is considered a highly efficient fuel.
(B) Future Applications of Hydrogen
(i) Energy Carrier Hydrogen will join electricity as an important energy
carrier in the future. This is because it can be made safely from renewable
energy sources and is virtually nonpolluting.
(ii) Electricity Production Hydrogen will be used to produce electricity in
fuel cells.
(iii) As a Fuel Hydrogen will be used as a fuel for ‘zero-emission’ vehicles, and
for aircraft.
(iv) In Heating Hydrogen will also be used to heat offices and homes.
(C) Infrastructure Many new facilities and systems must be built before hy-
drogen can play a bigger role and become a widely used alternative to gasoline.
(D) Limitations of Hydrogen Energy The use of hydrogen as an alterna-
tive future source of energy is limited by
(i) Its low availability in pure H2 form in the environment
(ii) Difficulty in handling, storing and transportation of H2
(iii) Requirement of energy for the production of H2
Fig. 2.42 Infrastructure requirement for hydrogen as a

source of energy for propelling vehicles
2.7.11 Ocean Energy or Marine Energy

Oceans cover more than 70% of the earth’s surface making them the world’s largest
solar collectors. Just a small portion of the heat trapped in the ocean could power
the whole population across the globe.
(A) Various Ways in which Energy from the Ocean can be Obtained
From the oceans, electrical power can be derived by the following methods:
(i) Wave power
(ii) Ocean Thermal Energy Conversion (OTEC)
(iii) Tidal power
(iv) Ocean currents
(v) Ocean winds
(vi) Salinity gradients
The first three technologies, viz. wave power, OTEC and tidal power, are the
most developed technologies. These are briefly described below.
(B) Wave Power The energy in waves comes from the movement of the ocean
and the changing heights and speed of the swells. It is estimated that the total power
of waves breaking on the world’s coastlines is 2 to 3 million megawatts. An average
4 foot, 10-second wave striking a coast puts out more than 35, 000 horse power per
mile of coast. This is equivalent to about 65 megawatts of wave energy density per
mile of coast.
One of the approaches to

capture wave energy is the use of
oscillating water columns (OWC).
Its simple design is illustrated in
Fig. 2.43. The OWC generates
electricity from the wave-driven
rise and fall of water in a cylindrical
shaft. The rising and falling water
column drives air into and out of
the top of the shaft, powering an
air-driven turbine. Fig. 2.43 Oscillating water columns for
The theoretical potential of harnessing wave energy of oceans
renewable energy from wave
energy is estimated to be of the order of 8000–80000 TWh/year.
(C) Ocean Thermal Energy Conversion (OTEC) The oceans absorb
enough heat from the sun every day to equal the thermal energy contained in 250
billion barrels of oil. Thus, a great amount of heat is stored in the world’s oceans.
This thermal energy is converted into
electricity by using ocean thermal energy
conversion systems. Closed-cycle plants are
one type of OTEC systems. Its simple
design is illustrated in Fig. 2.44. They
circulate a working fluid (which has a
low boiling point, such as ammonia) in
a closed system, heating it with warm
surface sea water, flashing it to vapour,
routing the vapour through a turbine,
and then condensing it with cold sea
water. The rotating turbine then activates Fig. 2.44 Ocean Thermal Energy
a generator to produce electricity. Conversion (OTEC) power plant
The theoretical potential of renewable energy from OTEC is estimated to be of
the order of 1000 TWh/year.
2.7.12 Geothermal Energy

Geothermal energy is a clean, renewable and environment-friendly energy source based
on the heat inside the earth.
The word geothermal comes from the Greek words:
Geo = Earth ; Thermal = Heat
Thus, the energy that can be extracted from the heat inside the earth is geothermal
energy.
In the earth’s core, about 4000 miles below the surface of the earth, geothermal
energy is continuously produced by the slow decay of radioactive particles. The
regions where the earth’s tectonic plates collide and one slides beneath another
create the conditions which are most favourable for the geothermal activity.
The geothermal heat gets up to the earth’s surface by the following mechanisms:
(i) Heat from the earth’s interior flows outward. It is transferred by conduction
to the outer layer of rock on the crust.
(ii) In some regions, the mantle beneath the crust may be hot enough to partly
melt and create magma. Magma rising upward out of the mantle (convection)
can bring intense shallow heat into the crust.
(iii) Through pores and crevices in the crust, rain water seeps down to depths
of a mile or more and gets heated. The heated water may be stored at
depths in geothermal reservoirs, or the hot water may flow upwards out of
the reservoir to the surface as hot springs, or boil near the surface to create
geysers, mudpots, and fumeroles.
In the past, people have used geothermal energy for the following purposes:
(i) Bathing Hot springs were used by ancient civilisations for bathing,
(ii) Heating Geothermal energy was used by early Romans to heat their homes.
(iii) Cooking Geothermal water was used for cooking by native Americans.
(iv) Medical Therapy Geothermal water was used by early Romans to treat eye
and skin diseases.
(A) Present Uses of Geothermal Energy Electricity generation, space
heating/cooling, greenhouses, aquaculture, drying of fruits/vegetables, and indus-
trial uses like manufacture of paper, washing wool, drying of cloth, etc.
In fact geothermal resources are available in the following temperature ranges
(Fig. 2.45).
Fig. 2.45 Availability of geothermal resources in different temperature ranges
(B) Merits of Geothermal Energy Some of the advantages of using geother-

mal energy to generate electricity are given below.
(i) Flexible With growing demand for energy, additional units with modular
designs can be installed easily, because there is no major land requirement.
(ii) Affordable The cost of electricity production is almost competitive with
conventional energy sources.
(iii) Sustainable It is believed that enough heat will be radiated from the centre
of the earth to fulfill human energy demand for all the times to come.
(iv) Clean Technology No emission and safe to use.
(v) Extraction Useful minerals (like zinc and silica) can be extracted from
underground water.
(vi) Reliable Energy can be harnessed continuously, Only water is used that
can also be recycled.
(C) Limitations of Geothermal Energy
(i) If the cooled water is not injected back into the reserve after the heat is
extracted, the following harmful effects are observed:
(a) Brine can salinate soil.
(b) Land subsidence can occur leading to an increase in seismic activity.
(c) Large quantities of H2S “the rotten-eggs” gas can be released and
inhaling it in too much quantities is fatal.
(ii) Geothermal hot spots are scattered and are at faraway regions than the areas
that need energy.
(iii) The overall production efficiency is lower.
(iv) At geothermal sites, drilling operations cause noise pollution.
(D) Electricity Generation
(i) Dry Steam Plants They
use underground steam to directly
turn the turbines (Fig. 2.46).
(ii) FlashSteamPlants These
plants pull deep, high-pressured
hot water (T = 360°F) to the
surface. This hot water is trans-
ported to low-pressure chambers Fig. 2.46 Dry steam plant
and the resulting steam drives the
turbines. The remaining water
and steam are then injected back
into the source from which they
were taken (Fig. 2.47).
Note: A temperature gradient of
40ºC/km exists is hot dry rock
when dug underground. If one
digs 20,000 feet underground,
the large temperature difference is
sufficient to produce electricity. Fig. 2.47 Flash steam plant
(E) Role of Geothermal Energy in India Global warming and climate

change is and will continue to be one of the key challenges the world has to face
along with India in the coming years. Geothermal energy could play a very impor-
tant role in mitigating these challenges by reducing dependence on fossil fuels and
provide clean energy.
India’s first geothermal power plant with an initial capacity of 25 megawatts will
be coming up in Andhra Pradesh’s Khammam district by 2012.
Geosyndicate Power Pvt. Ltd. is an incubated company of the Indian Institute

of Technology Bombay. APNPDC is Northern Power Distribution Company of
Andhra Pradesh.
India’s first geothermal Power Purchase Agreement (PPA) was signed in August
2010 between GeoSyndicate and APNPDC, under the aegis of the Nonconventional
Energy Development Corporation of Andhra Pradesh Limited (NEDCAP).
GeoSyndicate is India’s one and only Indian geothermal company who will play a
significant role in reducing the country’s carbon footprint by setting up geothermal
plants.
Geothermal power plants emit 0.893 kg CO2 per MWh while coal power plants
emit 953 kg CO2 per MWh. The combined geothermal potential of India amounts
to 18348 ¥ 1014 MWh.
245 ¥ 106 MWh (33%) of electricity generated from coal based thermal power
plants is utilised by domestic and commercial building sector. A major amount
of this energy is spent for hot-water supply, refrigeration and space cooling. This
amounts to emission of 234 ¥ 109 kg of CO2. India can save about 234 ¥ 107 euros
under CER by utilising geothermal sources. This resource can provide a stable supply
of energy, in contrast to many alternative domestic renewable energy resources like
wind, hydro and solar photovoltaic.
As per IEA 2007, the Indian food sector uses about 13% of the electricity
amounting to 63 ¥ 106 MWh. This energy is obtained from coal-fired thermal
power plants. By using geothermal sources instead of this, 600 ¥ 106 euros can
be raised through Clean Development Mechanism (CDM) and ploughed into
this industry. Thus, implementing CDM in food processing sector will help in
reducing CO2 emission and earning carbon credits.
If emission of CO2, SO2 and NOx is not controlled, it may lead to severe droughts
in India and other developing countries and reduce supplies of clean, fresh water to
the point where there are major threats to public health. With global water resources
already under severe strain from rapid population growth and expanding economic
activity, the danger is clear.
Fig. 2.48 Utilisation of geothermal energy in India

In India, there are nearly 400 low to medium enthalpy thermal springs. These are
distributed in seven geothermal provinces. These provinces include the Himalayas,
West Coast, Godavari, Mahanadi, Sohana, Cambay, Son–Narmada–Tapi rift zone
(SONATA).
The surface temperatures of these thermal springs vary from 47°C to 98°C. These
provinces are the sites for commissioning small-scale power projects using binary
plant technology. They are also the best sites for direct application technologies in
which heat energy is directly used by a variety of small-scale industries. Dehydration
of agricultural produce, food processing and food production can utilise this energy
with maximum profits (about 5 % to 8% total operating costs).
2.7.13 Wind Energy

Air in motion is know as wind. It is caused by the uneven heating of the surface of
earth by the sun. During the daytime, the air above the land heats up more quickly
than the air over water. The warm air over the land expands and rises, and the
cooler, heavier air rushes in to take its place, creating wind.
At night, the air cools more rapidly over land than over water; so the winds are
reversed.
The land near the earth’s equator is heated more by the sun than the land near the
North and South poles. This creats the atmospheric winds that circle the earth.
Fig. 2.49 Generation of wind
Wind is a renewable energy source because the wind will blow as long as the sun
shines.
(A) Good Sites for Wind Plants Over open areas that have no windbreaks
and with altitude, wind speed increases. Thus, the tops of smooth, rounded hills,
mountain gaps that produce wind funneling, open plains or shorelines are good sites
for wind plants.
(B) Advantages of Wind Energy (a Clean Source of Energy)

(i) Windmills do not release emissions that pollute the water or air.
(ii) They do not require water for cooling.
(iii) Windmills help in reducing the amount of electricity generation from
fossil-fuel based thermal power plants. Therefore, they help in reducing air
pollution and carbon dioxide emissions.
(iv) Many windmills are located on farm, grazing and forest land. The extra
income from windmills help farmers live a better life.
(v) Wind power projects are considered to be best alternatives to mountain-top
removal coal-mining projects for thermal power generation.
(vi) Offshore wind turbines on the ocean are considered even more environment
friendly than windmills on land.
(vii) Wind is an important renewable and sustainable source of energy, available
free of cost.
(viii) Power generation using windmills is very economical. This is because
running cost for windmills is almost negligible.
(ix) In large coastal, hilly and desert areas, laying of power transmission lines is
extremely difficult and costly leading to unavailability of electric power. In
such circumstances, wind energy is very useful.
Fig. 2.50 How does a wind turbine work?

(x) Wind power systems are specially useful for water pumping, battery charging,
operating simple machinery, hybrid energy (wind/diesel, wind/photovoltaic)
systems, etc., in remote areas.
(xi) The gestation period of installing wind turbines is short.
(C) Limitations of Wind Energy
(i) Wind energy is variable, irregular, erratic, intermittent, unsteady and some-
times dangerous.
(ii) Location sites for wind farms are generally away from cities.
(iii) Design, manufacture and installation of wind turbines is very complex because
of widely varying atmospheric conditions in which they have to operate.
(iv) Continuous whirling and whistling sound associated with rotation of blades
of windmills can be very irritating.
(v) The output of a single windmill is quite small and cannot be used for
commercial applications. Thus, a large number of windmills need to be
erected to make a wind energy farm. This requires a very large open area and
huge investment of money.
(vi) Cost of maintenance is very high because the towers and blades are exposed
to rain, sun, storm and cyclones.
(vii) The location of some windmills are on the routes of migratory birds. The
working of windmills in these locations cause bird deaths and decline in
their populations. The wind energy industry is researching ways to reduce
the impact of wind turbines on birds.
(viii) Initial cost for wind turbines is greater than that of conventional fossil-fuel
generators per MW of installed capacity.
(D) Wind Energy in India and the World
By the end of 2009, the worldwide installed capacity of wind power reached 157,889
MW. Top five wind-power producing countries in the world are listed below:
Table 2.15 Wind-power producing countries in the world
Country USA Germany Spain China India
Wind power 35,159 25,777 19,149 25,104 13065.37*
[Installed capacity (MW)]
The installed capacity of wind power as of 31st Dec. 2010
(i) In 2009–10, India’s growth rate with respect to wind power was highest
among other top four countries.
(ii) Wind power accounts for 6 % of India’s total installed power capacity.
(iii) India generates 1.6 % of the country’s power using wind.
The actual utilisation of wind power in India is low despite the high
installed capacity. This is because policy incentives are for installation rather
than operation of the plants. The Indian Government is still considering the
addition of incentives for ongoing operation of installed power plants.
(iv) In India, additional 6000 MW of wind power capacity will be installed by
2012.
(v) Suzlon is an Indian-owned company and the leading manufacturer of wind

turbines for the Indian market (with 52 % market share). It has made India
the developing country leader in advanced wind turbine technology.
(vi) Tamil Nadu is the state with the most wind generating capacity (4906.74
MW) at the end of March 2010.
(vii) Maharashtra (2077.70 MW) is second only to Tamil Nadu in terms of
generating capacity.
2.7.14 Tidal Energy

Periodic changes of water levels and the associated tidal currents, are due to the
gravitational attraction of the sun and moon. At a particular location, the magnitude
of tide is the result of
(i) the changing positions of the sun and the moon relative to the earth,
(ii) the effects of earth’s rotation, and
(iii) the local geography of the sea floor and coastlines.
Tidal power, or tidal energy, is a form of hydropower that converts the energy of
tides into electricity or other useful form of hydro power. Tidal power is a renewable
energy resource because the earth’s tides are practically inexhaustible.
(A) Power Generation Methods using Tidal Energy
The following methods are useful:
(i) Tidal Stream Generators (TSGs) TSGs make use of the kinetic energy of
moving water to power turbines. TSGs use moving water in the similar ways as wind
turbines use moving air.
Advantages Lower cost, lower ecological impact compared to tidal barrages.
(ii) Tidal Barrage They make use of the potential energy in the difference in
height between low and high tides. They are essentially dams across the full width
of a tidal estuary.
Motion of turbine blades help in the rotation of a coil of wire in a magnetic field
of an electric generator. This induces a flow of electricity in the wire.
Fig. 2.51 Kinetic energy of moving water is used to power turbines for harnessing
tidal energy using tidal barrage at (a) high tide, and (b) low tide
Drawbacks
∑ Very high civil infrastructure costs
∑ Higher environmental impacts
∑ A worldwide shortage of viable sites

In the Gulf of Kutch on India’s west coast, the Atlantis Resources Company will
start construction in early 2012 to install a 50 MW tidal farm. This will be south
Asia’s first commercial-scale tidal power station.
(B) Merits of Tidal and Wind Energy Resources A few important ad-
vantages of using tidal and wind energy are listed below:
∑ They are clean, renewable sources of energy.
∑ Consumption of tidal and wind energy does not create pollution.
∑ Use of tidal and wind energy reduces the dependence upon fossil fuels.
∑ They are highly efficient resources.
∑ Power generation using tides or waves does not create greenhouse gases.
(C) Demerits of Tidal and Wind Energy Resources A few important
disadvantages of using tidal and wind energy resources are given below:
∑ The initial construction cost for making the plant for harnessing tidal and
wind energy is very high.
∑ The required technology is not fully developed for harnessing tidal energy.
∑ Ecological impacts relating to alteration of tides and waves is not fully
understood.
∑ Waves are irregular in size, durability and direction; so they are a diffuse
energy source.
∑ Appropriate waves and tides are highly dependent on location.
∑ Required technology for transporting electricity from the sea onto the land
is yet to be discovered.
2.7.15 Advantages and Disadvantages of Various Sources

of Energy
Table 2.16 Advantages and disadvantages of various sources of energy
Advantages Disadvantages
(1) Coal ∑ Widespread availability ∑ Mining of coal is dangerous to man and
environment
∑ Low cost of coal. ∑ Transportation of coal and its combustion
in thermal power plants create pollution
∑ Easier transportation to power ∑ Nonrenewable
stations
∑ Technology is known and used ∑ Domestic reserves of good-quality coal
and supplying about 70% of are very less in India
energy requirement in India
(2) Nuclear ∑ Low nuclear fuel requirements ∑ Generates very harmful and radioactive
waste
∑ Energy production does not ∑ Nonrenewable because limited uranium
generate greenhouse gases reserves in the world; environmental
concerns regarding digging of uranium
mines in India
(Contd.)
(Contd.)
Advantages Disadvantages
∑ Operating cost is about the same ∑ Nuclear power stations are at risk from
as coal-based thermal power terrorist attack
plants
∑ Time consuming and expensive develop-
ment of nuclear power plants
(3) Wind ∑ Wind is free, renewable ∑ Number of wind turbines in the form
of wind farms are needed to generate
electricity; costly and requires large
open area
∑ Wind power generation does ∑ Availability of wind is variable
not create greenhouse gases
∑ Wind turbines are relatively safe ∑ Maintenance cost is also very high
(4) Hydro ∑ Hydro power does not create ∑ Electricity production is variable
greenhouse gases
∑ Relatively safe ∑ Expensive
∑ Renewable
(5) Tidal ∑ Predictable ∑ Technological limitations for harnessing
and distribution of energy
∑ Renewable ∑ Dam construction expensive and may
harm plants and animals
∑ No greenhouse gas emission ∑ Tides happen only twice a day so electric-
ity can be produced for that time only
(6) Geothermal ∑ Less costly ∑ Sites for building geothermal power sta-
tions are very limited
∑ Renewable, reliable ∑ While harnessing geothermal energy
∑ No greenhouse gas emission from underground, sometimes harmful
gases also come up, which is difficult
∑ Very useful for food processing
to control
sector and building sector
(7) Solar ∑ Renewable ∑ Construction of solar power station is
expensive
∑ Sun energy is free ∑ Electricity cannot be made during cloudy
days or during night
∑ No greenhouse gas emission
Case Studies
Energy Resources
(i) Waste To Energy (WTE)
With the fast depletion of conventional resources and the growing awareness and
concern regarding pollution created from their utilisation, there has been a major
thrust in the recent past to identify and develop alternate energy resources.
Waste To Energy (WTE) is a proven environment friendly process that

provides reliable electricity generation and is extensively used in Europe and
other developed nations in Asia. Municipal Solid Waste (MSW) is a waste type
that includes predominantly household waste (domestic waste) sometimes with
the addition of commercial garbage or refuse that is generated by commercial
establishments, industries, etc. Use of municipal solid waste as a fuel source is
governed by moisture and energy content of the waste material. The thermal
treatment of MSW results in the generation of 500–600 kWh of electricity per
ton of MSW combusted.
In a case study of Eluru, AP, India (2010), it is estimated that by combusting
the solid waste in Eluru Municipal Corporation, it is possible to generate nearly
3 MW of power.
(ii) Electrifying Rural India (Husk Power System)
In August 2007, HUSK Power Systems (HPS) lighted the first village from its
power plant. As of August 2010, HPS has installed 60 mini power plants that
provide power to 25,000 households in more than 250 villages.
The key advantages of HPS are the following:
(a) HPS electrifies rural India from its 100% biomass based power plant that
uses discarded rice husks to generate electricity.
(b) One mini power plant of HPS serves about 400 households and replaces
about 42,000 litres of kerosene and 18,000 litres of diesel per year.
(c) HPS power plants help in CO2 sequestration.
(d) HPS has employed and trained more than 300 local people in rural India for
running and managing its power plants.
(e) HPS plants are cheaper than the mega-size thermal power plants. The
generation, distribution and installation cost of HPS is about $1/W.
[http://www/huskpowersystems.com]
2.8 LAND RESOURCES

2.8.1 Land as a Resource
Land resources are natural resources in the form of productive land. Land resources
are essential for the survival and prosperity of humanity. These resources are also
essential for the maintenance of all terrestrial ecosystemss.
The basic functions of land in supporting human and other terrestrial ecosystems
are given below:
(i) Land is a store of wealth in its own.
(ii) Land is a storehouse of minerals and raw materials for human use.
(iii) Land helps in the production of food, fibre, fuel, etc.
(iv) Land is the biological habitat for many plants, animals and microorganisms.
(v) Land regulates flow of surface water and stores groundwater.
(vi) Land enables or hampers movement of people and animals between one
place to another.
(vii) Land is a buffer, filter or modifier for chemical pollutants.

(viii) Land is co-determinant in the global energy balance and the global hydrologi-
cal cycle, which provides both a source and sink for greenhouse gases.
(ix) Land is the physical space for settlements, industry and recreation.
(x) Land stores and protects evidence of past climates, archaeological remains
from the historical or prehistorical record.
2.8.2 Texture, Structure and Composition of Soil

Soil is an uncemented aggregate of mineral grains and decayed organic matter with
water and air occupying the void spaces between particles.
Soil texture refers to the size distribution of soil particles and the relative percentage
of sand, silt and clay in a soil. Three sizes of particles are recognised in soil. These
are tabulated below:
Soil Type Fine-Texture Clays Medium-Textured Silt Coarse-Textured Sand
Particle Size < 2 mm (2 – 50) mm > 50 mm
The relationship between particle size and class names is shown in Fig 2.52.
It is to be noted that a clay soil remains clay and a sandy soil remains sandy
because the size of particles in the soil is not subject to ready change.
90
10
80
20
y
ay cla
Clay
Pe
Cl ent
rc
rc
en
Pe
Silty
t
Sandy
Sil
clay clay
t
s
am
Sandy Silty
Clay loam
Lo
clay loam clay loam

ay
Cl
20
Loams
80
Sandy Silty
10
loam loam
am
90
Lo
Sand
Per cent Sand

90 80 20 10
Fig. 2.52 Percentages of sand and clay in major soil textural classes: (a) Sandy
clay contains more sand than clay. (b) Soils with the best structure for
most crops have to retain water and dissolve mineral nutrients. These
soils are various types of loams, viz. sandy loam, silty loam, etc.
Soil texture controls the following properties of soil with respect to plant growth:
(i) aeration,
(ii) availability and movement of water,
(iii) content of plant nutrients, and
(iv) workability.
For instance, movement of water in various soil-textured types is illustrated in

Fig. 2.53.
Water
Loam-type Soil
Clay Soil
Sandy Soil
Particles
Pore
Particle size : Big Big and small (mixture Small

of Sand and Clay)
Number of pores : Few More Many
Size of pore Large Varying Small
Water drainage : Free and fast Slow but still poor and slow, water
well drained tends to get trapped
Fig. 2.53 Water drainage from various types of soils
(A) Soil Structure

Soil structure refers to the arrangement of soil particles into groups or aggregates.
The peds are natural, fairly water stable aggregates; and clods are artificial, water
unstable aggregates. Ploughing of wet clay soil makes the soil cloddy.
Soil structure is divided into the following groups:
(a) Types of soil structure.
Examples: Platy, spheroidal, etc
(b) Class of soil structure.
Examples: Fine, medium, coarse, etc.
(c) Grades of soil structure.
Examples: Weak, strong, etc.
(B) Soil Composition
Four major components of soils are mineral materials, organic matter, water and air.
Approximate composition of soil is given below:
Soil Constituent Mineral Materials Organic Matter Water Air
Volume Per Cent 45 5 20–30 30–20
(i) Mineral Materials

(a) Mineral materials are elements (Si, Fe, O, Mg, Al, Ca, Na and K), finely
divided quartz (SiO2), iron-silicates and aluminium silicates.
(b) They are derived from the underlying bedrock or from materials transported
and deposited by surface run-off, wind flow, etc.
(c) Secondary minerals (viz., Na+, K+, Ca2+, Mg2+, H+, NH+4) are held at the
surface of all the silicate clays. These are not leached by water and are
exchanged. Thus, they are available as plant nutrients.
(ii) Organic Matter
(a) Organic matter can be crop residues, weeds, grasses, bacteria, fungi, other
microorganisms and animal manures.
(b) They come from the residues of plants and animals.
(c) Functions
∑ They provide food for microorganisms, other nutrients to plants. Thus, soil
productivity is controlled by them.
∑ They provide a storehouse for nutrients.
∑ They increasing waterholding capacity of soil.
(iii) Water It is a good solvent for many nutrients which move into plant roots.
Water is also important to maintain the proper form and position of leaves and new
shoots for capturing sunlight and satisfactory growth.
(iv) Air Soil air encourages optimum rate of the essential metabolic processes of
various organisms.
2.8.3 Land Degradation

In the face of the rapidly changing global situation, humanity is not paying attention
to manage resources efficiently for sustainable future. Because of this land resources
are under stress and the world is facing outcomes of declining crop production,
increased land degradation, increased competition for land, etc.
Most persons are trapped in the downward spiral (Fig. 2.54) in which resource-
limited farmers have shortage of land resources. They are even further degrading these
limited resources by inappropriate farming practices in order to satisfy immediate
subsistence needs. Decision-makers often face a situation where requirement is to
increase production and reduce poverty, but at the same time resources must be
conserved to prevent environmental degradation. Most of the time, short-term political
Migration
Lack of proper
land policies
Expansion
of land Land
Old obsolete pressure
Unsustainable area
technologies
land use
Higher birth rates
Poor subsistence Land erosion
+
Low income Land degradation
Less education, no health care
Poverty and family welfare services
Fig. 2.54 Causes of land degradation

gains have been made at the expense of long-term environmental damage. It is

becoming more difficult for technological progress to keep up with the increasing
demands generated by population explosion. This is partly a result of the extension
of cropping to more marginal areas where risks of failures are higher and productivity
is limited by physical factors. Externalities related to global change are also a major
constraint to sustainable land management.
It is necessary to apply an integrated planning approach for the sustainable
management of land resources (Fig. 2.55). This is because land in different regions
varies greatly in productive potential. There
is no universal technological solution for
meeting human needs while protecting
the terrestrial biosphere. This integrated
planning approach requires establishment
of improved land policies that will enable
informed decisions to be made about land
resources. Improved access to information
and technology and the capacity to use them
are essential for right decision making. This
will help in sustainable land use and higher
production per unit area. Fig. 2.55 Sustainable land use
(A) Landslides A landslide means ground movement in offshore, coastal and
onshore environments. This geological phenomenon includes deep failure of slopes,
rock falls and shallow debris flows.
Causes When the stability of a slope changes from a stable to an unstable
condition (due to either natural or human causes), landslides occur.
(a) Natural Landslide Causes include groundwater pressure acting to destabilise
the slope, earthquakes adding weight to barely stable slopes, earthquakes causing
liquefaction, destabilising slopes, and volcanic eruptions. These causes are illustrated
in Fig. 2.56.
Fig. 2.56 Landslides as a result of translational ground movements. (A) Landslide

caused by fill placement (B) Landslide caused by earthquake
(b) Human Induced Landslides Human activities aggravate landslides by

destabilising already fragile slopes. Human causes include vibrations from machinery
or traffic; blasting; the removal of deep-rooted vegetation that binds colluvium to
bedrock in shallow soils; construction, and agricultural or forestry activities which
change the amount of water which infiltrates the soil.
(B) Soil Erosion Soil erosion is the wearing away of soil or geological material from
one point on the Earth’s surface to be deposited elsewhere.
Normally, soil erosion is a natural process which occurs over geological time
scales. It occurs because of various physical forces such as rainfall, flowing water,
wind, temperature change, gravity, etc.
By anthropogenic activity, rate of soil erosion significantly increases compared
to the natural rate and it becomes a process of degradation. Tillage, mechanical
influences, etc., are anthropogenic factors.
The natural factors of soil erosion are wind and water. Wind velocity and rain-
splash dislodges soil particles that initially fly through the air (saltation). Slope wash
causes overland flow. Wave motion in streams, rivers and lakes causes slumping
of bank material. The various forces responsible for soil erosion are illustrated in
Fig. 2.57.
Fig. 2.57 Forces responsible for soil erosion
Table 2.17 Consequence of soil erosion

On-site Off-site
(i) Loss of productivity of soil (i) Diffuse pollution of soil and water by
contaminants and nutrients
(ii) Reduction of functional capacity of soil (ii) Destruction of habitats, damage to property,
infrastructure, etc
(iii) Silting of lakes, reservoirs and river courses
(C) Desertification
Desertification, or land degradation, means irreversible decline in the ‘biological
potential’ of the land. It is a process in which the soil loses its productivity and
becomes infertile.
(i) Causes Desertification is caused by natural and/or man-made reasons.

Some of these are climate change, deforestation, overcultivation, overgrazing, dam
construction, mining, urbanisation, industrialisation, etc.
(ii) International Efforts to Prevent Desertification The following steps
should be taken at international and national levels to control desertification:
∑ Sustainable usage of available groundwater resources
∑ Management of land use and farming techniques, etc; control of overgrazing
∑ Generation of public awareness, imposing ban on cutting of desert vegetation
∑ Plantation of ecologically suitable plants
2.9 CONSERVATION OF NATURAL RESOURCES

(A) Need for Conservation of Natural Resources Conservation means
wise use. We need to conserve natural resources so that present and future genera-
tions will be able to use natural resources to fulfill their needs of food, shelter and
clothing.
There is an urgent need for the conservation of natural resources because over-
utilisation of natural resources has totally disturbed the ecological balance of the
environment leading to pollution, extinction of species and disturbance in the food
chain. This measurable degree of damage up to and including a state beyond use or
repair is known as destruction.
(B) Methods and Tools for Conservation of Natural Resources
People belonging to different disciplines should take care of the following:
(i) Reduce usage of nonrenewable natural resources such as fossil fuels.
(ii) Preferably use renewable and environment-friendly energy resources like
solar energy, wind energy, etc.
(iii) Avoid deforestation and conserve forest resources.
(iv) Help in afforestation by planting trees along the roadside, wastelands, etc.,
through social forestry programmes.
(v) Use biogas for cooking instead of fuel wood in rural areas.
(vi) Turn off unused appliances to reduce energy requirements.
(vii) Reduce usage of vehicles for energy saving avoiding pollution and conserving
natural resources.
(viii) Preferably use ecofriendly products made through green technology.
(ix) Use less paper, reuse paper and recycle paper for saving forest and water
resources.
(x) Donate money for conservation activities.
(xi) Reduce the use of chemical fertilisers. Use compost. It is a mix of dead plants
and dirt which is buried underground for a few weeks. The compost can
then be digged out for addition to soil and making it fertile and healthy.
(xii) Help governments to protect an entire wetland or a large section of tropical
rainforest.
(xiii) Find more creative conservation solutions and then share ideas with many
for timely action.
(xiv) Make a plan based on good natural resource information for the rational
use of natural resources. For this, take help from satellite imagery and maps,
GIS based analysis, real-world 3D modelling, statistical analysis of ecosystem
services through software and many more.
2.10 SUSTAINABLE LIFESTYLES

Sustainable lifestyle or sustainable living is the application of sustainability to lifestyle
choices and decisions.
Sustainable lifestyle attempts to reduce an individual’s or society’s use of the
natural resources by shifting to a renewable energy-based, reuse/recycle economy
with a diversified transport system.
(A) Need for Sustainable Lifestyles The major cause of the continued de-
terioration of the global environment is the unsustainable patterns of consumption
and production, particularly in the industrialised countries. Sustainable lifestyles
and practices in agriculture, forestry, fishing, and manufacturing need to be maxi-
mised so that pollution and waste an be minimised.
(B) Relationship Between Population and Food Production
For survival, people need to eat food. Thus, when the population increases, the food
production will have to increase.
When there is a lack of land and water to grow food, there are large chances for a
lack in food supply to meet the hunger need of the rising population. This leads to
more starvation deaths which limits the population growth.
Impact on food production (I) is governed by population (P), Affluence (A) and
Technology (T ) as per the following relation:
I = f (P ¥ A ¥ T )
(i) Population (P) Keeping other factors constant, the more people there are,
the greater is the impact on the environment, and the greater is the impact on food
production capacity.
In many poor countries, rapid population growth directly results in land
fragmentation. Often landholdings which are too small to provide a sufficient
livelihood are sold to wealtheir landowners, making land distribution uneven and
adding to the increase in landless labourers. As more land is in large holdings, the
poor are forced to live on small holdings or in marginal areas.
Rapid population growth can lead to inappropriate farming practices, (like over-
use and improper use of agrochemicals, water resources, etc.) resulting in severe land
degradation and decline in food production.
When population growth is unchecked, it grows geometrically. However, food
supply generally grows arithmetically because of a limited area of cropland. This
leads to famine and rise in the death rate so as to balance population size and its
food supply.
Fig. 2.58 Relationship between population and food production.

(ii) Affluence (A) Lifestyle, income and social organisation determines the level
of consumption of food. Poverty may prevent the adoption of a more appropriate
technology that could halt or slow down environmental degradation. Affluent and
awarded people can easily practice improved resource management technique for
increasing crop yields.
(iii) Technology (T) The technologies in practice determine the extent to which
human activities damage or sustain the environment. It also determines the amount
of waste associated with a given level of consumption.
By using improved production techniques, improved seeds, accurate weather
forecasts, etc., farmers can maximise agricultural food production.
(C) Equitable Use of Resources for Sustainable Lifestyles
By equitable use of resources, it is possible to improve energy security while reducing
the impact on climate. It is also possible to improve food and water security while
reducing biodiversity degradation. This is because to generate economic value, it is
a must to generate the resources on which it relies. Our prosperity is dependent on
the prosperity of biodiversity (Fig. 2.59).
Fig. 2.59 How health and prosperity are linked with energy security and
biodiversity. (Source: newanthropocene.wordpress.com)
(A) Present approaches to secure food and water availability are leading to
increasing natural environment fragmentation, pollution and unsustainable
harvest. These approaches are harming biodiversity.
(B) Biodiversity provides the following valuable services:
(a) Aerates and improves soil, water and air quality
(b) Composes new, useful material
(c) Decomposes spent material
(d) Converts sunlight to chemical energy, etc.
Thus, conservation of biodiversity is a must for food and water security.
(C) As economy improves, green cover on land is reduced, concrete cover increases,
emission of greenhouse gases increases, protection from floods, cyclones, etc.,
decreases. All these leads to intensification of climate change effects.
(D) Energy availability governs the access of products and services. The demand
for energy is rising day by day. As a result, fuel price is increasing, increasing
price of consumables/personal transport/energy reliant services.
(E) As efficiency and security of energy improves, access to products and services
likewise improves.
(F) When access to goods and services is dependent upon fossil fuels, it impacts
climate change through increasing greenhouse gas emissions.
(G) Climate change results in heat and storm surge so it impacts all aspects of
biodiversity, from distribution to damage.
(H) As the effects of food and water security increase, ecological services (such as
green cover, carbon sequestration, storm surge protection) are reduced. This
results in increasing the effects of climate change.
As is illustrated in Fig. 2.59, it is obvious that our wealth presently depends on
undermining the wealth of natural resources and energy requirements. Thus, to
have prosperous and sustainable societies, it is a must to improve (B) and (E) while
reducing (A), (C), (D), (F), (G) and (H).
2.11 SUSTAINABLE WATER MANAGEMENT (SWM)

The purpose of sustainable water management is simply to manage our water resources
while taking into account the needs of present and future users.
Sustainable water management is based on the following principles devised in 1992
during the International Conference on Water and the Environment (ICWE):
(i) Freshwater is a finite and valuable resource. It is essential for sustaining life,
environment and development.
(ii) Users, planners and policymakers, all must participate in development and
management of our water resources.
(iii) Women play a central role in the provision, management and safeguarding
of water resources.
(iv) Economic and policy incentives must be given to manage water resources
properly.
(A) Problem or Factors Limiting the Adoption of SWM in India

(i) Policy Failures and Institutional Weaknesses Only government agencies
are involved for water development projects (with full funding). There are policy
failures on whether the demand for water was met by public, cost recovery and
continued abuse of water resources.
(ii) Competition for Water Even presently, the urban, agricultural and
industrial demands for water are greater than the available supplies.
(iii) Past projects did not fully address the health and environmental needs.
(B) Action Plan for SWM
(i) Right Planning Environment, health, agriculture and other sectors must
cooperate for the management of water resources. Each must understand the need
of the other group and must be accountable for its actions. Policies should encourage
demand management rather than continuing with the old policies of developing
supplies of water resources.
(ii) Optimisation of the Use and Distribution of the Current Water
Supplies This can be done through appropriate actions for water conservation.
For this, all should join hands for
(a) reducing wastage and leakage,
(b) regulating demand,
(c) using low-flow technologies,
(d) reclaiming waste water, and
(e) reusing water, etc.
(iii) Right Budgeting The needs of the ecosystem to maintain its functions must
be included in water-balance budgets. The government should facilitate generation
of sufficient data on the links between health and water quality.
(iv) Right Decision-making Process Government, industry, law and public,
all should be involved in the decision-making process.
2.12 BIOGEOCHEMICAL CYCLE

A circulating pathway by which a chemical (an element or a molecule) moves
through both biotic (bio) and abiotic (geo) compartments of an ecosystem is termed
the biogeochemical cycle. The most important biogeochemical cycles are those of
carbon, nitrogen, water, etc.
Biogeochemical cycles are essentially the continuous transport and transformation
of materials in the environments and so these are also termed material cycles.
In natural systems, the flow of material and energy is circular. The wastes that
living creatures excrete are degraded and become nutrients to living organisms.
Likewise, when living creatures die, they too biodegrade to nutrients.
2.12.1 The Carbon Cycle

The carbon cycle is a complex series of processes through which all of the carbon
atoms in existence rotate.
In the carbon cycle, plants absorb carbon dioxide from the atmosphere and through
photosynthesis convert this CO2 and water into oxygen and carbohydrates, which they
need for growth. Animals breathe in this oxygen, eat the plants and use the carbon
of carbohydrates to build their own tissues. These animals return carbon dioxide into
the air, when they breathe and when they die, as the carbon is returned to the soil
during decomposition. The carbon atoms in the soil may then be used in a new plant
or small microorganisms. When we burn fossil fuels like oil, the carbon in the fuel
combines with atmospheric oxygen to form carbon dioxide (Fig. 2.60). Every ton of
CO2 emitted from combustion of fossil fuels changes the carbon cycle for thousands
of years as it upsets the carbon balance in the atmosphere. The current excessive levels
of CO2 lead to global warming, climate change, floods, droughts, etc.
Fig. 2.60 The carbon cycle
Carbon exists in the nonliving environment as

(i) Carbon dioxide in the atmosphere and by forming bicarbonates, it gets
dissolved in water
(ii) Carbonate rocks (like limestone CaCO3)
(iii) Deposits of coal, petroleum, and natural gas derived from once-living things
(iv) Dead organic matter, e.g. humus in the soil
Carbon enters the biotic world through the action of producers (or autotrophs):
(i) Primarily photoautotrophs (like plants).
They use the energy of light to convert carbon dioxide to organic matter.
(ii) And to small extent, chemoautotrophs (like bacteria).
They do the same but use the energy derived from an oxidation of molecules
in their substrate.
Carbon returns to the atmosphere by
(i) respiration (as CO2),
(ii) burning or combustion of fossil fuels, and
(iii) decay (producing CO2 if oxygen is present, methane if oxygen is not present).
However, the uptake and return of CO2 are not in balance. The CO2 content of
the atmosphere is gradually and steadily increasing.
2.12.2 The Nitrogen Cycle

Nitrogen and its compounds are essential constituents of protein which is the
building block of all living organisms. The ultimate source of nitrogen is atmospheric
nitrogen but plants or animals are incapable of assimilating free nitrogen.
The process of converting atmospheric nitrogen to useful nitrogenous compounds
by plants, passing it to animals and then the decomposition of these compounds to
give back free nitrogen in the atmosphere is called the nitrogen cycle (Fig. 2.61). The
percentage of nitrogen remains constant in the air because of the nitrogen cycle.
Fig. 2.61 The nitrogen cycle (detailed)

Fig. 2.62 The simplified nitrogen cycle
The nitrogen cycle consists of following steps:

Step (i) Fixation of Nitrogen The process of conversion of free nitrogen of the
air to useful nitrates is termed nitrogen fixation. This can be achieved by
(a) Microorganisms like rhizobium (a nitrogen-fixing bacteria) present in the
roots of leguminous plants.
(b) Atmospheric thunder and lightning
(c) Addition of compost and fertilisers.
Step (ii) Entry of Nitrogen in Plants and Animals The nitrates in the soil
are absorbed by plants as mineral salts. Plants convert the inorganic nitrates to
organic proteins. The proteins from the plants enter the body of animals in the
form of food.
Step (iii) Ammonification and Nitrification Processes for Returning
Nitrogen to the Soil When plants and animals die, their bodies decompose.
The organic proteins undergo a series of chemical changes, brought about by
microorganisms, which convert the proteins back to inorganic nitrates.
In humans and animals, some proteins are broken down to ammonia and carbon
dioxide, which forms urea and is excreated out in urine. Waste matter of animals
and humans is also treated by microorganisms to convert it into inorganic nitrates.
Step (iv) Denitrification Denitrifying bacteria found in the soil convert nitrates
of the soil to free nitrogen which escapes to the atmosphere and thus completes the
cycle and maintains the atmospheric balance of nitrogen concentration.
Impacts of Human Activities on the Nitrogen Cycle Human activities

have altered and upset the nitrogen balance. The application of nitrogen fertilisers
to crops has caused increased rates of denitrification and leaching of nitrates into
groundwater streams, rivers, lakes, etc. The added nitrogen in these systems leads
to eutrophication.
2.12.3 The Sulphur Cycle

Sulphur enters the atmosphere through both natural and human sources in the
form of oxides of sulphur (SOx). It reacts with rain and falls into earth as acidic
sulphate (SO42–) deposition. The sulphate is absorbed by plants as it is required for
making amino acids, proteins, etc. Animals consume these plants, so that they take
up enough sulphur to maintain their health. This is because sulphur is important for
the functioning of enzymes and proteins.
A simplified version of the pathways, transformations, and chemical species in a
sulphur cycle is illustrated in Fig. 2.63.
(i) Sulphate (SO42–) is reduced to hydrogen sulphide (H2S) by Sulphate-
Reducing Bacteria (SRB).
(ii) Some sulphate is assimilated by organisms to form cell components such as
amino acids and co-factors.
Fig. 2.63 The sulphur cycle

(iii) Organic sulphur is converted to H2S upon mineralisation.

(iv) H2S is transformed to elemental sulphur (S°).
(v) Sulfide oxidising bacteria convert S° into SO42–.
(vi & vii) Anoxygenic phototrophic bacteria also convert H2S to SO42– via elemental
sulphur.
(viii) Sulphur-reducing bacteria transform back the elemental sulphur to H2S.
(ix) Some H2S complexes with iron to form black FeS precipitates, whose
recycling is slow.
Role of Human Activities in Sulphur Cycle Human activities such as coal
mining, petroleum extraction and burning of coal and natural gas result in increase
of sulphur content in the atmosphere.
SO2 gets released as air pollutant. It reacts with moisture in the air and sulphuric
acid is formed. It is responsible for acid rain which causes severe damage to natural
and man-made ecosystems.
Case Studies
(i) Packaged and Processed Foods
(a) Canned foods with large amounts of sodium or fat.
(b) Breads and pastas made with refined white flour instead of whole grains.
They have potassium bromate to increase their volume.
(c) Frozen fish sticks and frozen dinners contain excessive quantities of sodium.
(d) Packaged chips, candies, cakes and cookies have high calories.
(e) Processed meats such as ham, hot dogs, sausage, etc., contain sodium
nitrate for maintaining colour and increasing shelf life.
Commonly used preservatives used in packaged and processed foods and
their harmful effects are listed below:
∑ Calcium, Potassium and Sodium Salts These result in high blood pressure,
kidney damage, worsening of heart-related diseases, calcification of tissues etc.
∑ Sulphites They worsen asthma.
∑ Boric Acid It causes cancer damage to kidneys and testis.
∑ Sodium Benzoate Responsible for allergies and liver problems.
∑ Phosphoric Acid Responsible for bone weakening, kidney stones and kidney
damage.
∑ Sodium Nitrate It is known to worsen asthma and decrease lung function.
∑ Potassium Bromate When breads and other bakery products are not cooked
long enough or not at a high temperature, a residual amount of this oxidising
agent will remain in bread, which may be harmful if consumed.
∑ Sodium Benzoate and Benzoic Acid These are food preservatives found in
sauces, fruit juices, jams and pickled products. If used over the permissible
limit, regular intake of products containing these can cause allergic reactions
and other side effects.
Solutions
(a) Always read the label of pre-packaged food products for chemical content.
(b) High BP patients, kidney patients and heart patients should avoid too much
of packaged food, particularly meat items that have high salt content.
(c) Choose fresh food over processed foods.
(ii) Population in India
(a) As per census 2011
(i) Population of India is 1.2 billion.
(ii) It is almost equal to the combined population of the US, Indonesia, Brazil,
Pakistan, Bangladesh and Japan (1214.3 million).
(iii) Absolute addition (181 million since 2001) is slightly lower than the
population of Brazil, the fifth most populous country in the world.
(iv) Uttar Pradesh (with 200 million people) is the most populous state.
(v) Lakshadweep is the least populated at 64,429.
(vi) India now makes up 17.5 % of the world’s population.
(b) 586.5 million Females and 623.7 million males.
Table 2.18
Decade Population Growth Rate (%)
1951–1961 21.64
1961–1971 24.80
1971–1981 24.65
1981–1991 23.87
1991–2001 21.54
2001–2011 17.64
(vi) 60% of the population lives in the top seven states.
(vii) Uttar Pradesh and Maharashtra together now are home to more people
than those in the United States of America.
∑ Natural resources are objects, materials, creatures, or any form of energy found in
nature that can be used to perform any useful function.
∑ Perpetual resources are those natural resources that naturally perpetuate themselves
and are not affected by human use.
∑ Renewable resources are those natural resources that have the inherent ability to
renew or replenish themselves if given a reasonable amount of time.
∑ Nonrenewable resources are those natural resources that cannot be regenerated or
renewed or replaced within a time framework.
∑ Intangible resources are those natural resources that are available in huge quantities,
but at the same time can be destroyed easily.
∑ Biotic resources have originated from some living organism or have life.
∑ Abiotic resources are of nonliving origin.
∑ Forests help in production of timber, regulation of stream flow, control of erosion,

recreation, provision of wildlife habitat, etc.
∑ Deforestation can be defined as the change of forest with depletion of tree crown
cover of more than 90%. However, depletion of forest-tree-crown cover less than
90% is considered as forest degradation.
∑ Timber extraction is the removal of timber from forests.
∑ Logging is the work or business of felling and trimming trees and transporting the logs
to a mill.
∑ Mining in the extraction (renewal) of metals and minerals from the earth.
∑ A dam is a huge and giant barrier constructed across a river to obstruct its natural
flow.
∑ Water resources are sources of water that are useful or potentially useful to humans.
∑ Life is impossible without water. It is needed for health, ecosystem services, economic
development, poverty reduction, protection of greenery, production of food and
imparting of aesthetic beauty.
∑ Water conservation is the most cost-effective and eco-friendly way to reduce our
demand for water.
∑ Water-borne diseases are illnesses caused by consuming water contaminated by
pathogenic microorganisms.
∑ Flood is a temporary covering by water of land not normally covered by water.
∑ Drought may be defined as the deficiency of rainfall (relative to the statistical multi-
year average for a region ) over an extended period of months or years.
∑ Meteorological drought is brought about when there is a prolonged period with less
than average rainfall.
∑ Agricultural drought is a drought that affects crop production or the ecology of the
range.
∑ Hydrological drought is brought about when the water reserves available in sources such
as reservoirs, lakes or aquifers fall below the statistical average.
∑ Natural resources in the form of minerals are known as mineral resources.
∑ A mineral which can be extracted and processed at a profit is known as an ore.
∑ Food security is defined as the physical and economic access to sufficient, safe,
nutritious food for maintaining a healthy and active life.
∑ Undernourishment means to receive less calories than needed.
∑ Malnourishment means lack of essential nutrients (like proteins, vitamins, lipids,
minerals, etc.) in the diet.
∑ Overnourishment is due to overconsumption of saturated (animal) fats, sugar and salt
in diet.
∑ Overgrazing can be defined as grazing plants (by livestock or wildlife) for extended
periods of time or without sufficient recovery periods.
∑ Agriculture means the cultivation of soil and or production of crop plants or livestock
products. It is synonymous with farming: the field-dependent production of food,
fodder, and industrial organic material.
∑ The term modern agriculture depicts the push for innovation, stewardship and
advancements continually made by farmers to sustainably produce higher quality
products with a reduced environmental impact.
∑ Organic farming is based on development of biological diversity and the maintenance
and replenishment of soil productivity through crop rotation, use of animal and green
manures, and some forms of biological control of pests.
∑ Sustainable agriculture means meeting the food needs of the present generation
without endangering the resource base for the future generation.
∑ The Green Revolution refers to the rapid increase in food production mainly through
the use of High-Yielding Varieties (HYVs) of seeds, chemical fertilisers, pesticides,
agriculture machinery and water.
∑ Green Revolution means better food-production methods or better agricultural

practices to secure the world food supply.
∑ Fertilisers are substances (natural or synthetic) that are added to the soil to restore
and enhance the soil fertility to improve the quality and quantity of plant growth.
∑ Pest is any organism that causes an economic loss or damage to the physical well
being of human beings.
∑ Risk (damage) by pesticide is determined by both toxicity (hazard) and the likelihood
of exposure.
∑ There is an increase in concentration of pesticides in successively higher trophic levels
of a food chain or food web in a process known as bio-magnification.
∑ Waterlogging means too much water in the root zone of a plant so that roots cannot
absorb enough oxygen to breathe.
∑ Salinity means accumulation of soluble salts in the soil due to over-irrigation.
∑ Energy is the ability to do work.
∑ Conventional energy sources are energy sources which are nonrenewable. However,
nonconventional energy sources are energy sources which are renewable and ecologi-
cally safe.
∑ Hydroelectricity or hydroelectric power is the electricity obtained by harnessing the
power of water flowing down from a high level.
∑ Petroleum and coal are formed from the fossilised remains of animals and plants,
hence they are known as fossil fuels.
∑ Coal is defined as stratified rock, consisting of organic matter of fuel value derived
from the partial decay and alteration of accumulated plant materials by the action of
heat and pressure over millions of years.
∑ Petroleum is a complex mixture of paraffinic, olefinic and aromatic hydrocarbons with
small quantities of organic compounds containing oxygen, nitrogen and sulphur.
∑ Nuclear fission: When an unstable nucleus of a heavy atom (like uranium–235) is
bombarded with neutrons, the former splits up into two medium weight nuclei with
the liberation of an enormous amount of energy.
∑ Nuclear fusion: When two lighter nuclei (like deuterium atoms) are heated to a very
high temperature (~106°C), they fuse together to form a heavy, more stable nucleus
and an enormous amount of energy is liberated.
∑ Solar energy is the energy received by the earth from the sun that is converted into
thermal or electrical energy. Solar energy influences the earth’s climate and weather
and sustains life.
∑ The term biomass is used for the dead plants and trees (e.g. wood, crop residue, etc.)
and the waste material of living organisms (e.g. cattle dung, sewage, etc.).
∑ Biogas consists mainly of methane. It burns with a blue flame and its average calorific
value is about 5300 kcal/m3.
∑ Green fuel (or biofuel) is a type of fuel obtained from nonfood sources like green algae
which is more environmental friendly than the widely used and quickly disappearing
fossil fuels.
∑ Hydrogen is a very light gas, and its density is eight times less than that of natural gas.
There are no significant problems with regard to transportation, dispensation as well
as end use of hydrogen.
∑ Oceans cover more than 70% of the earth’s surface making them the world’s largest
solar collectors. Just a small portion of the heat trapped in the ocean could power the
whole population across the globe.
∑ Geothermal energy is a clean, renewable and environment-friendly energy source
based on the heat inside the earth.
∑ Air in motion is know as wind. It is caused by the uneven heating of the surface of
earth by the sun.
∑ Wind is a renewable energy source because the wind will blow as long as the sun
shines.
∑ Tidal power, or tidal energy, is a form of hydropower that converts the energy of tides
into electricity or other useful form of hydro power. Tidal power is a renewable energy
resource because the earth’s tides are practically inexhaustible.
∑ Land resources are natural resources in the form of productive land. Land resources
are essential for the survival and prosperity of humanity. These resources are also
essential for the maintenance of all terrestrial ecosystems.
∑ Soil is an uncemented aggregate of mineral grains and decayed organic matter with
water and air occupying the void spaces between particles.
∑ Soil texture refers to the size distribution of soil particles and the relative percentage
of sand, silt and clay in a soil.
∑ Soil structure refers to the arrangement of soil particles into groups or aggregates.
The peds are natural, fairly water stable aggregates; and clods are artificial, water
unstable aggregates. Ploughing of wet clay soil makes the soil cloddy.
∑ A landslide means ground movement in offshore, coastal and onshore environments.
This geological phenomenon includes deep failure of slopes, rock falls and shallow
debris flows.
∑ Soil erosion is the wearing away of soil or geological material from one point on the
Earth’s surface to be deposited elsewhere.
∑ Desertification, or land degradation, means irreversible decline in the ‘biological
potential’ of the land. It is a process in which the soil loses its productivity and becomes
infertile.
∑ Conservation means wise use. We need to conserve natural resources so that present
and future generations will be able to use natural resources to fulfill their needs of
food, shelter and clothing.
∑ The purpose of sustainable water management is simply to manage our water
resources while taking into account the needs of present and future users.
∑ Sustainable lifestyle or sustainable living is the application of sustainability to lifestyle
choices and decisions.
∑ By equitable use of resources, it is possible to improve energy security while reducing
the impact on climate. It is also possible to improve food and water security while
reducing biodiversity degradation.
∑ A circulating pathway by which a chemical (an element or a molecule) moves through
both biotic (bio) and abiotic (geo) compartments of an ecosystem is termed the
biogeochemical cycle.
∑ Biogeochemical cycles are essentially the continuous transport and transformation of
materials in the environments and so these are also termed material cycles.
∑ The carbon cycle is a complex series of processes through which all of the carbon
atoms in existence rotate.
∑ The process of converting atmospheric nitrogen to useful nitrogenous compounds by
plants, passing it to animals and then the decomposition of these compounds to give
back free nitrogen in the atmosphere is called the nitrogen cycle.
EXERCISES
Based on Natural Resources 2. Distinguish between reserves and
1. What are the different types of nat- resources.
ural resources? 3. Give the classification of natural re-
sources.
4. Discuss the associated problems of 7. What are the problems associated

the unequal consumption of natural re- with the over-exploitation of water re-
sources. sources?
5. Why do we conserve natural re- 8. State and describe different sources
sources? of water.
6. Give in detail different types of re- Based on Mineral Resources
newable resources available and used 1. What are the environmental effects
in India and problems because of over- of using mineral resources?
exploitation of them. 2. What are the effects on environment
Based on Forest Resources due to extraction of mineral resources?
1. What is the importance of forest Based on Food Resources
resources for economic and ecological 1. What are the impacts caused by ag-
wealth of a country? ricultural activities?
2. Describe uses and over-uses of land 2. What is undernutrition and malnu-
and forest. trition?
3. Describe the key benefits of forests. 3. State the biochemical effects of
4. How can we estimate and explain pesticides.
socio-economic and environmental im- 4. Write a short note on effects of
pacts of deforestation? modern agriculture.
5. What are the different benefits ob- 5. What are the effects of modern agri-
tained from forest resources? culture on food resources?
6. What are the causes of deforesta- 6. Describe the relationship of popula-
tion of India? Describe briefly its effects tion and food production.
on the environment.
7. Write a short note on consequences Based on Energy Resources
of deforestation. 1. State the merits and demerits of us-
8. Describe in detail types of forest re- ing geothermal energy.
sources and the problems created by 2. Write a short note on wind energy.
deforestations in India. Also discuss its advantages and limita-
tions.
Based on Water Resources 3. What are green fuels?
1. Without water, life is impossible, 4. State the advantages and limita-
Justify it. tions of using hydro energy.
2. Explain the water cycle and the 5. What are the different types of en-
problems that arise with disturbances ergies which can be derived from the
to the water cycle. ocean? Explain briefly along with their
3. Explain by drawing a sketch of the advantages and limitations.
hydrological cycle. 6. What are renewable and nonrenew-
4. Describe in detail the uses and over- able energy sources?
uses of water resources in India. 7. Explain the limitations and impor-
5. Enlist different surface and ground- tance of solar energy.
water sources and explain how over- 8. What is the role of geothermal en-
exploitations of water resources exag- ergy in India?
gregate the problem of availability of 9. List the different nonconventional
safe drinking water energy sources. What new thrusts are
6. “Water shall be the source of the being given to renewable energy pro-
world’s next big conflict.” Explain. gramme in India?
10. Explain in detail conventional 5. Discuss land use planning for mini-
(nonrenewable) and nonconventional mising land-associated problems.
(renewable) energy sources with envi- Based on Conservation of Natural
ronmental problems created by the use Resources
of each of them. 1. What is the need of conservation of
11. What are various sources of en- natural resources? Discuss the different
ergy? Explain in detail any one noncon- tools used for conservation of natural
ventional source of energy. resources.
12. Describe the merits and demerits 2. Explain the different areas of envi-
of nuclear power energy and discuss ronmental conservation to which peo-
the major concerns regarding its use ple belong to different disciplines can
for electricity generation in India. contribute.
Based on Land Resources 3. Write a short note on destruction
1. Write a short note on desertification. versus conservation.
2. What are the causes of land degra- Based on Sustainable Lifestyle and
dation? Sustainable Water Management
3. Discuss about the soil texture, struc- 1. Discuss the need for sustainable
ture and its composition. lifestyles.
4. What are the sources/factors re- 2. Write about sustainable water man-
sponsible for soil degradation? agement.

I. Fill in the Blanks 9. _________ means meeting the needs
1. Major purpose of most of the dams of the present without compromising
around the world is _________. the ability of future generations to
2. A fuel cell in order to produce meet their own needs.
electricity burns _________. 10. When the sum total of nature’s
3. _________ declared that big dams resources (natural capital) is used
are temples of modern India. up faster than it can be replenished,
4. Energy and manure together are _________ of environment occurs.
supplied by _________. 11. _________ is an example of on-site
5. _________ became the first African effect of agriculture on environment.
woman to receive the Nobel Peace Prize 12. Climate change is an example
for “her contribution to sustainable of _________ effect of agriculture on
development, democracy and peace.” environment.
6. GH Brundtland is an international 13. _________ are major causes of
leader in _________ and public health. childhood lead poisoning.
7. _________ means the removal of 14. Intensive irrigation without
minerals or metals from earth’s soil. drainage causes _________.
8. Environmental impact assessment 15. World Nature Conservation Day is
is a systematic process of predicting recalled on _________.
environmental, social and economic 16. Chipko movement in Tehri Garhwal
impacts of a proposed project prior to region was initiated by _________ to
_________. conserve forests.
17. Most biotic resources are _________. 3. Largest fresh (c) Loss of
18. Overgrazing results in _________. water lake in the biodiversity
19. Green plants are also called the world
_________.
20. The disease caused by excess of 4. Deforestation (d) Lake superior
fluoride in water is known as ________. III. Multiple Choice Questions
21. The largest portion of water is used 1. Biogas predominantly contains
for _________. (a) CH4 (b) NH3
22. Deforestation takes place in (c) SO2 (d) Ethane
mountain region due to _________. 2. Both power and manure are pro-
23. World Water Day is recalled on vided by a
_________. (a) thermal plant
II. Match the following terms. (b) biogas plant
Match the terms of column I with (c) nuclear plant
appropriate terms of column II. (d) hydroelectric plant
A. 3. Steam reforming is currently the
least expensive method of producing
Column I Column II (a) CNG (b) petrol
1. Coal (a) Earth (c) hydrogen (d) biogas
2. Solar energy (b) Lignite 4. Peat, lignite, bituminous and an-
thracite are different types of
3. Nuclear energy (c) Sun
(a) biogas (b) natural gas
4. Geothermal (d) Fission and (c) nuclear fuel (d) coal
energy fusion 5. Identify the nonrenewable energy
B. resource from the following:
(a) Coal (b) Tidal power
Column I Column II
(c) Wind power (d) Solar energy
1. Substandard hous- (a) Biodiversity 6. Power generation by which of the
ing loss following is least polluting?
2. Ecodesigning of (b) Asthma (a) Coal (b) Natural gas
houses (c) Gasoline (d) Crude oil
3. Socially acceptable (c) Reduced 7. Extensive planting of trees to
economic and envi- pollution increase forest cover is called
ronmentally compli- (a) afforestation
ant mining operation (b) social forestry
(c) deforestation
4. Vehicular emission (d) Sustainable (d) agroforestation
mining 8. Deforestation generally decrease
5. Habitat fragmen- (e) CO2, NOx, (a) drought (b) rainfall
tation by roads or particulate (c) global warming
railway tracks matter (d) soil erosion
C. 9. Which of the following is a nonre-
newable resource?
Column I Column II
(a) Forest (b) Wildlife
1. Metal ores (a) Aluminium (c) Coal (d) Water
2. Bauxite (b) Mining 10. Fossil fuel and mineral resources are
(a) renewable (b) perpetual
(c) inexhaustive 2. The rural energy source in India is

(d) nonrenewable wood and animal dung. True/False
11. Fluoride pollution mainly affects. 3. The largest production of hydro en-
(a) teeth (b) heart ergy is carried out in Canada.
(c) kidney (d) brain True/False
12. Material cycles go through. 4. Nuclear energy often causes thermal
(a) biosphere and lithosphere pollution. True/False
(b) atmosphere and hydrosphere 5. Power generation by hydro energy
(c) biosphere and hydrosphere is least polluting. True/False
(d) all the four spheres 6. Deforestation is taking place only in
13. A forest is a complex community developing countries. True/False
with 7. Population explosion is one of the
(a) birds and animals reason for deforestation. True/False
(b) flora and fauna 8. Cleaning of forest for agriculture is
(c) plants and trees deforestation. True/False
(d) all the above 9. Cauvery water dispute is in between
Karnataka and Tamil Nadu. True/False
IV. Indicate True or False for the
10. Khetri (Rajasthan) is famous for
following statements.
copper mines. True/False
1. Hydro-power energy and biomass
11. Mosquito is an example of Bacteria.
energy are renewable energy sources.
True/False
True/False

I. Fill in the Blanks 20. Fluorosis
1. electricity production 21. Irrigation
2. H2 22. Hydel projects and road construc-
3. Pandit Jawaharlal Nehru tion
4. biogas plant 23. March, 22nd
5. Dr. Wangari Muta Maathai
II. Matching the terms.
6. Sustainable development
A. 1. (b) 2. (c) 3. (d) 4. (a)
7. Mining
B. 1. (b) 2. (c) 3. (d) 4. (e) 5.
8. Decision making
(a)
9. Sustainable development
C. 1. (b) 2. (a) 3. (d) 4. (c)
10. Degradation
11. Soil erosion III. Multiple Choice Questions
12. Off-site 1. (a) 2. (b) 3. (c) 4. (d)
13. Lead based paints 5. (a) 6. (b) 7. (a) 8. (b)
14. Water logging 9. (c) 10. (d) 11. (a) 12. (d)
15. July 28th 13. (d)
16. Sunderlal Bahuguna IV. True or False
17. Renewable 1. True 2. True 3. True 4. True
18. Desertification 5. True 6. False 7. True 8. True
19. Producers 9. True 10. True 11. False
3
ECOSYSTEM
Learning Objectives
∑ define ecology and ecosystem
∑ describe the causes and basic types of ecological succession
∑ enumerate and explain different types of ecosystems
∑ explain the roles of producer, consumer and decomposer in an ecosystem
∑ enumerate and explain various types of food chains
∑ explain the flow of energy through the various components of the ecosystem
∑ describe grassland ecosystem, desert ecosystem, forest ecosystem and
aquatic ecosystem
∑ define an ecological pyramid and its various types
∑ explain different models of energy flow in an ecosystem
∑ describe why a complex ecosystem is more stable than one with few species
3.1 INTRODUCTION TO ECOLOGY AND

ECOLOGICAL SUCCESSION
The term ecology is derived from the Greek word Oikologie. Literally, Oikos means
‘home or surroundings’ and logos means ‘study’. Thus, ecology is the study of nature.
Ecology can be defined as “the study of interactions between an organism and its
physical environment; the relationship between animals and plants and how one species
affect another.”
3.1.1 Classification of Ecology

Ecology can be classified
(i) By Level of Complexity or Scope For example, behavioral ecology,
population ecology, etc.
(ii) By Organisms under Study For example, animal ecology, plant ecology,
insect ecology, etc.
(iii) By Biome under Study For example, desert ecology, forest ecology, etc.
(iv) By Geographic or Climatic Area under Study For example, tropical

ecology, polar ecology, etc.
(v) By Spatial Scale under Study For example, micro ecology, macro ecology,
molecular ecology, global ecology, etc.
(vi) By Phenomena under Investigation For example, chemical ecology,
evolutionary ecology, etc.
(vii) By Technique used for Investigation For example, theoretical ecology,
quantitative ecology, etc.
(viii) By Philosophical Approach For example, conservation ecology,
restoration ecology, applied ecology, etc.
(ix) Ecology-involved Interdisciplinary Fields For example, human ecology,
agro ecology, etc.
3.1.2 Evolution of Ecosystems

An ecosystem is evolved through the following evolutionary processes:
Natural selection, life history, development, adaptation, populations and inheritance.
3.1.3 Ecological Succession

Ecological succession is orderly changes in the composition or structure of an ecological
community. It is more or less predictable.
(A) Causes and Basic Types of Ecological Succession
(i) Primary and Secondary Succession
(a) When the development begins on an area that has not been previously
occupied by a community, the process is known as primary succession.
Examples A lava flow, a newly formed lake, or a newly exposed rock or
sand surface.
(b) When the community development is proceeding in an area from which a
community was removed, it is called secondary succession.
Examples It arises on cut-over forest, an abandoned crop, etc. These are the
sites where the vegetation cover has been disturbed by nature or humans.
(ii) Seasonal and Cyclic Succession These are periodic changes arising from
fluctuating species interactions or recurring events.
Example Vegetation changes which are not dependent on disturbance unlike
secondary succession.
(B) Causes of Plant Succession
(i) Changes in the soil caused by the presence of organisms there includes
change in pH of soil by plants growing there, alterations of soil nutrients, etc.
(ii) Changes in the soil caused by external environmental influences includes
soil changes due to erosion, deposition of silt and clays, changes caused by
animals, etc.
Ecosystem 3.3
(iii) Changes caused by climate factors are promoted by changes in temperature

and rainfall patterns, specially global warming, floods etc.
3.2 ECOSYSTEM
“An ecosystem is defined as a natural unit that consists of living and nonliving parts
which interact to form a stable system.”
An ecosystem is generally an area within the natural environment in which
physical (abiotic) factors of the environment, such as rocks and soil, function together
along with interdependent (biotic) organisms, such as plants and animals, within
the same habitat to create a stable system. It possesses all the characteristics required
to sustain life. When we want to conserve species or to use natural resources in a
sustainable manner, we need to focus on ecosystems. This is because an ecosystem
is the minimal grouping of diverse organisms that interact and function together so
as to sustain life.
The sizes of some ecosystems are illustrated below:
Ecosystem Bacteria Pond Desert Ocean
2 2 2
Size (1 to 100) mm (10 to 100) m > 100 km > 1000 km2
example 1 How is the sun the primary sustainer of life on the earth?
OR
Wshat sustains life in an ecosystem?
Solution The energy from the sun
(i) enables plants to produce food through photosynthesis,
(ii) evaporates water and cycle it through the biosphere,
(iii) generates winds,
(iv) warms the atmosphere and the land,
(v) drives the climate and weather systems, and
(iv) powers the cycling of carbon, nitrogen and other matter.
Balanced Ecosystem
The biotic (living) and abiotic (nonliving) parts of the ecosystem are in equilibrium
in a balanced ecosystem. Balanced ecosystem means that the nutrients are able to cycle
efficiently, and no community of organisms or natural phenomena is interrupting
the flow of energy and nutrients to other parts of the ecosystem.
3.2.1 Structure of an Ecosystem
Structure of an ecosystem means:
(i) The Composition of Biological Community It includes species, their
population, etc.
(ii) The Quantity and Distribution of Abiotic Materials It includes water,
soil, nutrients, etc.
(iii) The Conditions of Existence It includes temperature, light, humidity, etc.
Fig. 3.1 Structure of an ecosystem
(A) Abiotic Components All the nonliving components of the environment

constitute the abiotic components. It includes:
∑ Inorganic substances which are involved in mineral (nutrient) cycles.
Examples: C, N, P, K, S, H, etc.
∑ Organic substances present in the biomass or in the environment. They form
the living body and influence the functioning of the ecosystem. Examples:
Carbohydrates, proteins, lipids, humus, etc.
∑ Climate factors having a strong influence on the ecosystem.
(i) Water Plants and animals receive water from the soil and the earth’s surface.
Water is the medium by which mineral nutrients enter and are distributed in plants.
For the survival of animals, water is necessary.
(ii) Soil Soil provides nutrients and water, a structural growing medium for
organisms.
(iii) Atmospheric Air Within ecosystems, the atmosphere provides oxygen for
respiration of organisms and carbon dioxide for photosynthesis in plants.
(iv) Sunlight Sunlight is necessary for photosynthesis. It is used to heat the
atmosphere in ecosystems.
(B) Biotic Components
All the living components of the environment constitute the biotic components.
Ecosystem 3.5
Depending on their self-food producing capability, biotic components are of

following types.
(i) Producers or Autotrophic Components Producers are self-nourishing
organisms (so they are called autotrophs). They contain chlorophyll and are capable of
converting carbon dioxide and water, in the presence of sunlight into carbohydrates
through photosynthesis. In the process, they give out oxygen.
Photosynthesis
6CO2 + 6H2O + Sunlight Producers C6H12O6 + 6O2
Fig. 3.2 Process of photosynthesis
Autotrophs are of the following two types:

(a) Photoautotrophs These are the producers who fix energy from the sun and
store it in complex organic compounds.
Light
Simple inorganic Photoautotrophs Complex

compounds organic compounds
Examples Green plants, some bacteria, algae.

(b) Chemoautotrophs (Chemosynthesizers) They are bacteria that oxidise re-
duced inorganic substances (typically ammonia and sulphur compounds) and
produce complex organic compounds.
Reduced Complex
inorganic Chemoautotrophs organic
compounds compounds
Example Nitrifying bacteria in the soil underground.

(ii) Consumers (or Heterotrophic Components) Consumers depend on
producers to obtain their energy for survival. They utilise, rearrange and decompose
the organic matter produced by autotrophs.
Heat
Complex Heterotrophs Simple

organic compounds inorganic compounds
Consumers are classified as herbivores, carnivores and top carnivores depending

on their food habits.
(a) Herbivores (or Primary Consumers) They feed on green plants (autotrophs)
to obtain energy for survival.
Seed-eaters are also known as granivores. Fruit-eaters are also known as
frugivores.
Examples Grasshoppers, rabbits, goats, cows, horses, etc.
(b) Carnivores (or Secondary Consumers) They feed on primary consumers.
Examples Lizard, fox, hawk, etc.
(c) Top Carnivores (or Tertiary Consumers) They eat the flesh of both carnivores
and herbivores and are not killed or eaten by other animals.
Examples Lions, tigers, vultures, etc.
Fig. 3.3 Structure of an ecosystem
(iii) Decomposers The decomposers are also known as saprotrophs (i.e. sapros
= rotten; trophs = feeder). They feed on dead organic matter (from producers
and consumers). They transform complex organic compounds back into simple
inorganic substances like CO2, H2O, phosphates, sulphates.
Examples Bacteria, fungi, other microbes, etc.
Fallen leaves, parts of dead trees, and faecal wastes of animals are termed detritus.
The consumers that feed on detritus are known as detrivores.
Examples Ants, termites, earthworms, crabs, etc.
Decomposers and detrivores are essential for the long-term survival of a
community. Their vital role is to complete the matter cycle. Enormous wastes of
plant litter, dead animal bodies, animal excreta, and garbage would collect on the
earth without them. Furthermore, important nutrients would remain indefinitely
in dead matter. The producers would not get their nutrients, and life would be
impossible without detrivores and decomposers.
Ecosystem 3.7
Notes:
∑ Humans act as primary consumers when they eat fruits and vegetables.
∑ Humans act as secondary consumers when they eat meat.
∑ Humans act as tertiary consumers when they eat the fish that eat smaller
fish that eat the algae.
∑ Humans can also act as omnivores by eating both plants and animals.
3.2.2 Function of an Ecosystem

Major functions of an ecosystem are as follows:
(i) It regulates flow rates of biological energy. In other words, it controls the rate
of production and respiration of the community.
(ii) It regulates flow rates of nutrients. In other words, it controls the production
and consumption of minerals and materials.
(iii) It helps in biological regulation including:
(a) Photoperiodism (regulation of organisms by environment)
(b) Nitrogen-fixing organisms (regulation of environment by the organism)
3.2.3 Importance of an Ecosystem

An ecosystem provides number of services for the healthy survival of humans. For
example:
(i) An ecosystem helps in water retention, thus facilitating a more evenly
distributed release of water.
(ii) An ecosystem provides air and does its purification.
(iii) An ecosystem provides recreation for us via eco-tourisms facilitating the
enjoyment of nature.
(iv) An ecosystem provides materials like minerals and food.
(v) An ecosystem regulates nutrient recycling and waste.

(vi) An ecosystem helps in erosion control, soil building and soil renewal.
(vii) An ecosystem helps in seed dispersal.
(viii) An ecosystem gives us solar energy (that accounts for 99% of the total energy
used on earth). It also gives us
(a) Renewable energy like biofuels, and
(b) Non-renewable energy like fossil fuels.
(ix) Additional services provided by an ecosystem are the following:
(a) An ecosystem helps in the maintenance of the biogeochemical cycles
like carbon cycle and water cycle. It also helps in the cycling of vital
chemicals like sulphur, phosphorus, nitrogen and carbon.
(b) An ecosystem helps in natural pest and disease control.

(c) An ecosystem preserves genetic diversity.
3.3 FOOD CHAIN

Food chain is a feeding hierarchy in which organisms in an ecosystem are grouped into
nutritional (trophic) levels and are shown in a succession to represent the flow of food
energy and the feeding relationship between them. The directional flow of food energy
from one organism to another is graphically represented by arrows. Food chain is
just a sequence of organisms, in which each is food for the next.
Fig. 3.4 A food chain

Food chains overlap, because most consumers feed on multiple species and in
turn, are fed upon by multiple other species. Thus, we have a complex network of
interconnected food chains called a food web.
For example, a snake might feed on a mouse, a lizard, or a frog. In turn, the snake
might be eaten by a bird or a badger.
Fig. 3.5 Food web in a forest

Types of Food Chains
Food chains are broadly of the following two types:
(i) Grazing Food Chain The grassland and forest ecosystems follow this grazing
food chain. Here, producers get energy from the sun and are grasses or green plants.
They are subsequently grazed by animals.
Examples (a) Grass Æ Grasshopper Æ Frog Æ Snake Æ Hawk
(b) Green plants Æ Goat Æ Wolf Æ Lion
(ii) Detritus Food Chain The estuarine and mangrove leaf ecosystems follow
this detritus food chain. In this chain, the dead animals, dead plants and fallen leaves
are consumed by detrivores and their predators.
Ecosystem 3.9
Examples (a) Dead plants Æ Soil mites Æ Insects Æ Lizards

(b) Dead organic matter Æ Bacteria Æ Protozoa Æ Rotifiers
example 2 How is balance maintained in an ecosystem?

Solution The food chains and other such interrelationships in ecosystems create
a balance in the environment, called the ecological balance.
The components of the ecosystem are part of food chains and food webs. They
do not try to modify the environment to suit their needs, rather they help in
maintaining a balance in the ecosystem.
However, humans try to modify the environment to suit their needs. As they are
also a part of these food chains and webs, modification of environment has upset the
delicate balance which was maintained in the environment.
example 3 What is the difference between a food chain and a food web?
Solution
(i) Food chains follow just one path of energy as animals find food. Food webs
show how plants and animals are connected in many ways to help them all
survive.
(ii) A food chain is the hierarchy of consumption of food from sun to plant to
herbivore to carnivore. It acknowledges only one single string of connected
plants/animals. There are many food chains within a food web, and one
creature is not necessarily at the top of the hierarchy. In a food web, one kind
of prey may be eaten by several kinds of predators, and one predator may eat
several different kinds of prey.
(iii) A food chain is very basic and doesn’t show the full picture of an ecosystem.
On the other hand, a food web refers to everything that goes on in the real
world.
(iv) A food chain can be illustrated by a linear diagram. However, a food web can
be illustrated by a complex diagram.
example 4 Explain the significance of studying a food chain.

Solution
(i) The knowledge of how species are inter-dependent in a food chain is
necessary. It is also necessary to understand how natural and man-made
environmental pressures affect ecosystems. These include mercury, DDT,
etc., which are toxic chemicals and cause destructive pollution. They can
alter or break the food chain. These also include nutrient pollution which
shift whole ecosystems toward nutrient-hungry species. For example, crops,
fertilizers, sewage and animal waste escape into lakes causing algae blooms at
the expense of fishes.
(ii) The study of food chains and webs is critical for understanding the route
by which pollutants gets bio-accumulated (i.e. concentrated) up the food
chain.
(iii) By studying a food chain, we can understand how balance is maintained in

an ecosystem.
3.4 ECOLOGICAL PYRAMIDS
3.4.1 Pyramid of Numbers

The pyramid of numbers represents the number of individuals at each trophic level.
The shape of a pyramid of numbers can be upright, partly upright and inverted
depending on the type of ecosystem.
(A) Aquatic and Grassland
Ecosystem Tertiary
In aquatic and grassland ecosystems, Consumers
the number of producers are Secondary
always more than that of primary Consumers
consumers. Thus, the producer
organisms remain in abundance Primary
near the base of the food chain and Consumers
the consumers gradually decrease

Producers
in number towards the apex. As a
result, the shape of the pyramid is Abundance
upright (Fig. 3.6 (a)). (a) Upright pyramid
Hyperparasites
Carnivores
Parasites
Herbivores
Herbivores
Producers
Producers
Abundance Abundance
(b) Spindle shaped

(c) Inverted pyramidal shaped
Fig. 3.6 Pyramid of numbers
(B) Forest Ecosystem

In a forest ecosystem, there are fewer number of producers that support a greater
number of herbivores who in turn support a lesser number of carnivores. The shape
of the pyramid of numbers is partly upright or spindle type (Fig. 3.6 (b)).
Ecosystem 3.11
(C) Parasitic Food Chain

In a parasitic food chain, one primary producer supports numbers of parasites which
again support still more hyperparasites. The pyramid of numbers is inverted in shape
because the producers are least in number and the predators are greater in number as
we move up the food chain (Fig. 3.6 (c)).
3.4.2 Pyramid of Energy Flow (Flow of Energy in an Ecosystem)

Flow of energy in an ecosystem takes place through the food chain.
The main source of energy for most ecosystems is the sun. Solar energy is trapped
by producers. They store it as carbohydrates, proteins and fats. When primary
Fig. 3.7 Pyramid of energy flow
consumers eat the producers, the energy also moves up the trophic level. During this
transfer, about 90% of the energy is lost as unusable heat to the environment.
We have an upright pyramid of energy flow as we move up the trophic levels, and
the amount of usuable energy available at each stage declines.
Notes:
1. The ecological pyramid is the graphical representation of the organism’s
position in the food chain. The base of the pyramid consists of the food-
producer level and the successive levels make the tiers with the top carnivore
or tertiary consumers forming the apex.
2. The size of each compartment in an ecological pyramid represents the
amount of organisms (or item) in each trophic level of a food chain.
3. Trophos is a Greek word meaning nourishment.
Suppose the producer has 10,000 units of energy. When primary consumers
eat the producer, they receive only 1000 units, and the rest 9000 units are lost as
heat. Similarly, the secondary and tertiary consumers gets only 100 and 10 units
respectively. The loss at each stage is simply released as heat into the environment.
The flow of energy through the various components of the ecosystem is unidirectional
and continuous.
Unlike the nutrients which move in a cyclic manner and are reused by the producers
after flowing through the food chain, energy is not reused in the food chain.
All organisms require energy for growth, maintenance, reproduction, locomotion,
etc. The flow of energy in an ecosystem follows the laws of thermodynamics.
(i) First Law of Thermodynamics Energy

can never be created or destroyed, but can be
converted from one form to another.
(ii) Second Law of Thermodynamics
Transformations of energy always result in
some loss or dissipation of energy.
The trophic structure of an ecosystem is
the pattern of energy flow among different Fig. 3.8 The trophic structure of
organisms as illustrated in Fig. 3.8. an ecosystem
3.4.3 Models for Energy Flow in Ecosystem

The following models can be used for explaining the flow of energy through various
trophic levels in an ecosystem.
(A) Universal Energy-flow Model According to this model (as per
E.P. Odum), as the flow of energy takes place, there is a gradual loss of energy
at every level, thereby resulting in less energy available at the next trophic level
as denoted by smaller boxes (for stored energy in biomass) and as indicated by
narrower pipes (for energy flow). The energy not utilised (NU) is lost in excretion,
locomotion, respiration (R). The rest of the energy is used for production (P).
Input energy = I
Assimilated energy = A
Production = P
Energy not utilised = NU
Fig. 3.9 Universal energy-flow model

(B) Single-channel Energy-flow Model According to this model, the flow
of energy takes place in a unidirectional manner from producers to herbivores to
Solar energy input = I

Gross primary production = GPP
Energy not utilised = NU
Net primary production = NPP
Energy not assimilated = NA
Respiratory loss = R
Fig. 3.10 Single-channel energy-flow model

Ecosystem 3.13
carnivores. Due to loss of energy at Grazing

food chain
each successive trophic level in a graz-
ing food chain, there is gradual decline Predators
in energy.
Sunlight R
Herbivores
(C) Double-channel or Y-shaped
Energy-flow Model Both graz- Plants R
ing and detritus food chain operate in Detritus
the same ecosystem in nature. In a ma- consumers
rine ecosystem, the grazing food chain
predominates. In a forest ecosystem, R
Predators
the detritus food chain predominates. R = Respiration Detritus
food chain
The grazing and detritus food chains R
are separated in space and time. A Y- Fig. 3.11 Y-shaped energy-flow model
shaped model of energy flow is used showing linkage between the
to show the passage of energy through detritus and grazing food chains
these two chains.
3.4.4 Pyramid of Biomass (Flow of Matter in an Ecosystem)

Estimation of Biomass
Step (1) Collect (or trap) and weigh suitable samples at each trophic level.
Step (2) Total combined (net dry) weight (often, per unit area or volume) of all
the organisms at each trophic level is biomass.
Fig. 3.12 Depicting biomass relationship graphically at successive

trophic levels gives rise to a biomass pyramid
The dry weight of all the matter contained in the organisms is known as biomass.
Each tropic level contains a definite amount of biomass. As we move up trophic
levels, biomass decreases drastically. There is 90 to 99 per cent loss of biomass at
each level. This is known as the pyramid of biomass.
Reasons for the decrease of biomass as we move up trophic levels are the
following:
(i) Only a fraction of the food taken in by a consumer is converted into body
tissue. The remaining is stored as energy to be used by the consumer when
needed.
(ii) Much of the biomass, especially at the producer level, is never eaten and goes
directly to the decomposers.
example 5 Why is the mass of water not usually included in biomass?

Solution This is because the water content is variable and contains no usuable
energy.
example 6 What is net primary production?

Solution Total amount of energy captured by producers is termed Gross Primary
Production (GPP).
When energy lost due to respiration is subtracted from GPP, we get Net Primary
Production (NPP).
NPP = GPP – Respiration
Net primary production is the amount of energy stored by the producers and
potentially available to the consumers and decomposers.
example 7 What is secondary productivity?

Solution It is the rate at which consumers convert organic material into new
biomass of consumers.
example 8 “The pyramid of total biomass produced must resemble the

pyramid of energy flow”. Comment.
Solution The above statement is TRUE.
This is because biomass can be equated to energy.
example 9 Why can the pyramids of energy and yearly biomass produc-
tion never be inverted?
Solution Because this would violate the laws of thermodynamics.
3.5 TYPES OF ECOSYSTEMS

There are several ecosystems working at micro and macro levels in the world. The
biosphere is the biggest ecosystem which combines all the ecosystems of the world.
The world’s smaller ecosystems are broadly divided into natural and artificial type
ecosystems.
3.5.1 Natural Ecosystems
They operate by themselves under natural conditions without any interference by
humans. Broadly they are subclassified into terrestrial and aquatic ecosystems.
Ecosystem 3.15
Fig. 3.13 Classification of ecosystems
(i) Terrestrial Ecosystems They are known by the type of main vegetation in
them. For example, grassland ecosystems have grass as the main vegetation.
(ii) Aquatic Ecosystems They are known by the type of habitat. They can be
of estuarine, marine and freshwater types of ecosystems.
The freshwater ecosystems can be of standing freshwater ecosystems (or lentic
ecosystems) or running freshwater ecosystems (or lotic ecosystems).
Examples Ponds, lakes, etc., are examples of lentic ecosystems and rivers, springs,
etc., are examples of lotic ecosystems.
3.5.2 Artificial Ecosystems

These ecosystems are controlled and manipulated by humans. These are created by
humans in order to fulfill certain needs.
Broadly, they are subclassified into the following two types:
(i) Agriculture ecosystem
(ii) Aquaculture ecosystem
(A) Differences between Natural and Artificial Ecosystems
Natural ecosystems Artificial ecosystems
(i) Polyculture systems (i) Monoculture system
(ii) Stable ecosystems (ii) Fragile ecosystems
(iii) Less productive in terms of yield of (iii) Highly productive as they are given increased
grains, milk, fish or meat supply of energy in the form of labour, extra
nutrients, fossil fuels, fertilisers, pesticides, etc.
(Contd.)
(Contd.)
(iv) Pollution free (iv) Generate lots of pollutants.
(v) Examples: Aquatic ecosystems and (v) Examples: Agriculture ecosystems and aquac-
terrestrial ecosystems ulture ecosystems
(vi) Functions: (vi) Functions:
∑ Air purification ∑ To supply large quantities of grains, etc.
∑ Water purification ∑ To supply large quantities of fish, meat,
milk, etc.
(B) Similarities between Natural and Arificial Ecosystems

(i) Both are open systems with no constraints of boundaries.
(ii) Both have all the essential components such as abiotic and biotic members.
(iii) Both permit constant interaction between biotic and abiotic components.
3.6 FOREST ECOSYSTEM

A forest is a community of trees, herbs, shrubs, and associated organisms that use
oxygen, water and soil nutrients for their growth and reproduction.
A forest ecosystem is the organisms, soil, air and water associated with the forest.
A forest ecosystem is interdependent because every organism depends on every
other living and nonliving elements of the system.
Fire, storms, drought, flood, death, disease, etc., are natural changes in a forest
ecosystem. Harvesting, farming, trails, recreation and development, etc., are man-
made changes in a forest ecosystem.
Components of Forest Ecosystems
The different components of the forest ecosystems are the following:
(i) Abiotic Components The minerals present in the forest and all organic
(litter, debris) and inorganic substances present in the soil and the atmosphere
constitute the abiotic components.
(ii) Biotic Components All living components, viz. producers, consumers and
decomposers, constitute the biotic components of the forest.
(a) Producers Big trees, medium-sized bush, small herbaceous plants, or any
vegetation of the forest is the producer, which performs photosynthesis.
(b) Consumers
Primary Consumers They graze over the primary producer, e.g. elephants,
mongooses, squirrels, deer; birds and insects like flies, spiders, ants, etc.
Secondary Consumers They are the predators of primary consumers. They regulate
the population size of primary consumers and thereby their grazing activity, e.g.
jackal, fox, eagle, snake, etc.
Tertiary Consumers They feed on secondary consumers and are also known as top
carnivores., e.g. lions, tigers, etc.
Ecosystem 3.17
(c) Decomposers They have the ability to degrade all dead organisms to release
nutrients into the soil which are again used by the producer. They remain confined
to the soil of the forest floor.
Examples Earthworms, bacteria, fungi, protozoa, nematodes, etc.
Fig. 3.14 Interconnection between food chain and food web in a forest ecosystem
3.7 AQUATIC ECOSYSTEM

An aquatic ecosystem is an ecosystem located in a body of water.
Biotic and abiotic components (which are self-regulating and self-sufficient)
constitute an aquatic ecosystem. About 70% of the earth’s total surface is under the
aquatic ecosystem. Broadly, an aquatic ecosystem is of the following three types:
Freshwater ecosystem, marine ecosystem and estuarine ecosystem.
3.7.1 Pond Ecosystem (or Freshwater Ecosystem)

The different components of a pond ecosystem are as follows:
(i) Abiotic Components Oxygen, carbon dioxide, water, nitrogen, phosphorus,
calcium, amino acids, etc., are abiotic components of a pond ecosystem.
(ii) Biotic Components They consist of the following:
(a) Producers Some photosynthetic bacteria and the autotrophic green plants fix
the solar energy with the help of nutrients obtained from the mud of the pond.
(b) Consumers
Primary Consumers They feed on the producers.
Examples Herbivores like zoo plankton and small invertebrates like copepod.
Secondary Consumers They feed on primary consumers.
Examples Small carnivores like small fishes.
Tertiary Consumers They feed on secondary consumers.
Examples Large fishes.
(c) Decomposers They help in the release and recycling of nutrients. They
decompose the organisms and are present at the base of the pond.
Examples Bacteria, fungi, etc.
Fig. 3.15 How food chain and food web are interconnected
in an aquatic ecosystem
Functions An aquatic ecosystem performs the following environmental func-

tions:
∑ Recycle nutrients
∑ Purify water
∑ Recharge ground water
∑ Provide habitats for wildlife
∑ Attenuate floods
∑ Used for human recreation
3.7.2 Marine or Ocean Ecosystem

Oceans are gigantic reservoirs of water covering nearly 70% of the earth’s surface. A
marine ecosystem is different from a freshwater ecosystem mainly because of its salty
water and also because the sea is deep, and the water is in continuous circulation.
A marine ecosystem can be divided into the following zones:
(A) Littoral Zone It is the shoreline between the land and the open sea. Waves
and tides have maximum effect in a littoral zone. Various regions of this zone are
tabulated below along with the important organisms:
Region Organisms
(i) Rocky shore region Starfish, barnacles, algae
(ii) Sandy shore region Snails, clams
(iii) Bays Algae
Often photosynthetic bacteria are present below the algae. Moreover, by colonial
coelenterates, coral reefs are also formed.
Ecosystem 3.19
Fig. 3.16 Horizontal and vertical zonation in the ocean

(B) Neritic Zone This zone lies just above the continental shelf. The nutrients
washed from land are found in this zone. Thus this zone is rich in species. The
productivity of this zone is high because sunlight can penetrate through this zone.
Zooplankton and phytoplankton are abundant here and support fishing grounds.
Pollution also affects the neritic zone first.
(C) Pelagic Zone The open sea constituting 90 per cent of the total ocean
surface forms this zone. Phytoplanktons, zooplanktons, shrimps, jelly fish, fin, deep-
water fishes and blue whale are found here.
Organisms of this zone are present below the light penetration zone and totally
depend on the rain of detritus of upper regions for their nutrition.
(D) Benthic Zone
The floor of the ocean constitutes this zone. It stretches from the edge of the
continental shelf to the deepest ocean trenches.
Sponges, sea lilies, sea fans, snails, clams, starfish, sea cucumbers and sea urchins
are found in this zone.
The components of marine ecosystem are the following:
(i) Abiotic Components High sodium, potassium, calcium and magnesium salt
concentrations, variable dissolved oxygen content, light and temperature make a
unique physico-chemical condition in marine water.
The size of marine populations is low because concentration of dissolved nutrients
is less.
(ii) Biotic Components
(a) Producers Phytoplankton, seaweeds and mangrove vegetations are main
producers in marine ecosystems.
(b) Consumers Crustaceans, molluscs, fishes and other herbivorous which feed
directly on producers are primary consumers.
Carnivorous fishes like herring, sahd and mackerel, etc., are secondary
consumers.
Cod, haddock and other top carnivorous fishes are tertiary consumers.
(iii) Decomposers These are microorganisms like fungi and bacteria.
3.7.3 Estuarine Ecosystem

Estuaries are semi-enclosed coastal bodies of water connected on the one side with a
river and on the other side with the open sea. Thus, estuarine is characterised as an
ecosystem having fluctuating water level.
The organisms present in estuaries are known as eurythermal (which show a
wide range of tolerance to temperature) and eurysaline (which show a wide range of
tolerance to salinity).
Due to nutrient and energy inputs from both river water and sea water, estuaries
are highly productive. They also offer high food potential for human beings. Deep-
water fishes use estuaries as nurseries to bring up their younger ones.
The component of an estuarine ecosystem are the following:
(i) Abiotic Components A mixture of fresh and marine ecosystems.
(ii) Biotic Components
(a) Producers Phytoplankton, benthic algae, sea grasses, seaweeds and marsh
grasses.
(b) Consumers Fishes, oysters, crabs, shrimp, etc.
(c) Decomposers Bacteria and fungi.
3.7.4 Streams and River Ecosystems or Flowing-water Ecosystems

The water flows rapidly in mountain
reaches. The lower reaches of rivers sustain
phytoplankton, zooplankton, crustaceans,
small fishes and big fishes. The river bottoms
are covered by algae and bacteria.
The trophic levels in a river ecosystem are
shown in Fig. 3.17.
Fig. 3.17 River ecosystem
3.8 GRASSLAND ECOSYSTEM

Grasslands are areas where the vegetation is dominated by grasses and other
nonwoody plants.
A grassland ecosystem is a biological community that contains grasslands.
About 32% of the plant cover of the world is covered with grasslands. The most
fertile and productive soils in the world have developed under grasslands. Generally,
the natural species have been replaced by cereals (cultivated grasses).
Grasslands occur in regions too moist for deserts and too dry for forests. The
annual rainfall in grasslands is usually seasonal. It ranges between 25 cm to 75 cm.
The principal grasslands include
(i) Steppes (Europe and Asia)
Ecosystem 3.21
(ii) Prairies (Canada, USA)

(iii) Pampas (South America)
(iv) Veldts (Africa)
The dominant animal species in grassland ecosystems include large mammals in
highest abundance and greatest diversity.
Examples Horses, asses, antelope, herds of bison, etc.
3.8.1 Components of a Grassland Ecosystem

The components of a grassland ecosystem are briefly discussed below:
(A) Biotic Components
(i) Producer Organisms Mainly grasses and a few herbs and shrubs contribute
to primary production of biomass.
(ii) Consumers Three main types of consumers in a grassland are
Primary Consumers They are herbivores feeding directly on grasses. These are
grazing animals.
Examples Cows, buffaloes, goats, sheeps, deer, rabbits, etc.
Secondary Consumers They are carnivores that feed on herbivores.
Examples Frogs, snakes, birds, foxes, lizards, etc.
Tertiary Consumers They feed on secondary consumers.
Examples Hawks, tigers, lions, etc.
(iii) Decomposers They attack the dead or decayed bodies of organisms, and
play an active role in their decomposition. In this decomposition process, nutrients
are released for reuse by producers.
Examples Bacteria, fungi, Actinomycetes, etc.
(B) Abiotic Components Abiotic components include inorganic and organic
compounds present in the soil and aerial environment.
The essential elements like C, H, N, O, P, S, etc., are supplied by water; nitrates,
sulphates, and phosphates are present in the soil and nitrogen is present in the
atmosphere.
3.9 DESERT ECOSYSTEM

Desert refers to a region or landscape in which the rainfall is negligible; and annual
rainfall is less than 250 millimetres. They occupy about 17% of the earth’s surface.
Deserts are characterised by
(i) scanty flora and fauna,
(ii) hot days and cold nights, and
(iii) soils with abundant nutrients but little or no organic matter.
Structure and Functions of a Desert Ecosystem
The structure and functions of biotic and abiotic components of a desert ecosystem
are as follows.
(i) Abiotic Components Nutrients present in the soil and air are abiotic
components. The organic substances are poorly present in the soil because of very
low rainfall and high temperature.
(ii) Biotic Components Biotic components are producers, consumers and
decomposers.
(a) Producers In a desert, producers are mainly shrubs/bushes, some grasses and
a few trees.
Examples Water-retaining plants adapted to arid climate or soil conditions
(succulents), hard grasses.
(b) Consumers They include animals which are capable of living in xeric
conditions.
Examples Insects, reptiles, etc.
Some nocturnal rodents, birds and some mammals like camel, etc., are also found.
(c) Decomposers In a desert ecosystem, decomposers are very few due to less
vegetation and very low amount of dead organic matter.
Examples Bacteria and thermophillic bacteria.
∑ Ecology is the study of interactions between an organism and its physical environment;
the relationship between animals and plants and how one species affect another.
∑ Ecological succession is orderly changes in the composition or structure of an ecological
community.
∑ When the development begins on an area that has not been previously occupied by a
community, the process is known as primary succession.
∑ When the community development is proceeding in an area from which a community
was removed, it is called secondary succession.
∑ Seasonal and Cyclic Succession are periodic changes arising from fluctuating species
interactions or recurring events.
∑ An ecosystem is defined as a natural unit that consists of living and nonliving parts
which interact to form a stable system.
∑ Balanced ecosystem means that the nutrients are able to cycle efficiently, and no
community of organisms or natural phenomena is interrupting the flow of energy and
nutrients to other parts of the ecosystem.
∑ All the nonliving components of the environment constitute the abiotic components.
∑ All the living components of the environment constitute the biotic components.
∑ Producers are self-nourishing organisms (so they are called autotrophs). They contain
chlorophyll and are capable of converting carbon dioxide and water, in the presence
of sunlight into carbohydrates through photosynthesis. In the process, they give out
oxygen.
∑ Photoautotrophs are the producers who fix energy from the sun and store it in complex
organic compounds.
∑ Chemoautotrophs (chemosynthesisers) are bacteria that oxidise reduced inorganic
substances (typically ammonia and sulphur compounds) and produce complex
organic compounds.
Ecosystem 3.23
∑ Consumers depend on producers to obtain their energy for survival. They utilize,
rearrange and decompose the organic matter produced by autotrophs.
∑ Herbivores (or primary consumers) feed on green plants (autotrophs) to obtain energy
for survival.
∑ Top carnivores (or tertiary consumers) eat the flesh of both carnivores and herbivores
are not killed or eaten by other animals.
∑ The decomposers are also known as saprotrophs (i.e. sapros = rotten; trophs = feeder).
They feed on dead organic matter (from producers and consumers).
∑ Fallen leaves, parts of dead trees, and faecal wastes of animals are termed detritus.
The consumers that feed on detritus are known as detrivores.
∑ Food chain is a feeding hierarchy in which organisms in an ecosystem are grouped into
nutritional (trophic) levels and are shown in a succession to represent the flow of food
energy and the feeding relationship between them.
∑ Food chains overlap, because most consumers feed on multiple species and in
turn, are fed upon by multiple other species. Thus, we have a complex network of
interconnected food chains called a food web.
∑ The pyramid of numbers represents the number of individuals at each trophic level.
The shape of a pyramid of numbers can be upright, partly upright and inverted
depending on the type of ecosystem.
∑ Flow of energy in an ecosystem takes place through the food chain.
∑ The ecological pyramid is the graphical representation of the organism’s position in
the food chain. The base of the pyramid consists of the food-producer level and the
successive levels make the tiers with the top carnivore or tertiary consumers forming
the apex.
∑ The size of each compartment in an ecological pyramid represents the amount of
organisms (or item) in each trophic level of a food chain. Trophos is a Greek word
meaning nourishment.
∑ First Law of Thermodynamics: Energy can never be created or destroyed, but can be
converted from one form to another.
∑ Second law of Thermodynamics: Transformations of energy always result in some loss
or dissipation of energy.
∑ The dry weight of all the matter contained in the organisms is known as biomass. Each
tropic level contains a definite amount of biomass. As we move up trophic levels,
biomass decreases drastically. There is 90 to 99 per cent loss of biomass at each level.
This is known as the pyramid of biomass.
∑ Natural ecosystems operate by themselves under natural conditions without any
interference by humans.
∑ Artificial ecosystems are controlled and manipulated by humans. These are created by
humans in order to fulfill certain needs.
∑ A forest is a community of trees, herbs, shrubs, and associated organisms that use
oxygen, water and soil nutrients for their growth and reproduction. A forest ecosystem
is the organisms, soil, air and water associated with the forest.
∑ An aquatic ecosystem is an ecosystem located in a body of water.
∑ A marine ecosystem is different from a freshwater ecosystem mainly because of its
salty water and also because the sea is deep, and the water is in continuous circulation.
∑ Estuaries are semi-enclosed coastal bodies of water connected on the one side with
a river and on the other side with the open sea. Thus, estuarine is characterised as an
ecosystem having fluctuating water level.
∑ Grasslands are areas where the vegetation is dominated by grasses and other nonwoody
plants. A grassland ecosystem is a biological community that contains grasslands.
∑ Desert refers to a region or landscape in which the rainfall is negligible; and annual
rainfall is less than 250 millimetres. They occupy about 17% of the earth’s surface.
EXERCISES
1. (a) What are the different tropic 11. Narrate in detail energy flow in
levels of organisms in an ecosystem? an ecosystem, Explain with one of the
(b) Why is a complex ecosystem more models of energy flow you have learnt
stable than one with few species? in the class.
2. Explain in detail the different 12. Explain the concept of food chain,
components of ecology. food web and ecological pyramid.
3. Describe the concept of ecosystem 13. What is an ecological pyramid?
and explain the relationship among Describe the pyramid of mass and
its different parts using a schematic energy with a sketch.
diagram. 14. Differentiate between food chain
4. How is an ecosystem evolved? Give and food web.
component parts of an ecosystem. 15. Explain pyramids of number in
5. Give a classification of ecology. parasitic food-chain energy flow with a
6. Give examples of aquatic and neat sketch.
terrestrial ecosystems. 16. Explain the significance of studying
7. How is balance maintained in an food chains.
ecosystem? Why is an ecosystem 17. How are food chains and food
with a large population of one species webs interconnected? Explain this with
considered to be not healthy? an example of aquatic or terrestrial
8. “Decomposers are very important in ecosystem.
an ecosystem”. Give reasons for validity. 18. Discuss the structure and function
9. What do you understand by of a desert ecosystem.
decomposers? Describe different 19. Write a short note on ‘marine
types of decomposers explaining their ecosystem’.
functions. 20. Explain pond ecosystem.
10. Enlist types of ecosystems. 21. Enumerate the aquatic ecosystems
Describe in detail the structure and and describe the structure of a pond
functions of an ecosystem. ecosystem stating its characteristic
features.

I. Fill in the Blanks 6. Producers produce ______ gas
1. Herbivores are ______ consumers. during photosynthesis.
2. Autotrophic planktons are called 7. Trophical rainforests occur in places
______ . where rainfall is more than ______ cm/
3. Dead plant parts and animal remains annum.
are called ______ . 8. In terrestrial ecosystems, 1000 kg
4. Each stage in a food chain is called of vegetation can support (a) ______
a ______ . kg of herbivores, which can support
5. A food chain starts with ______ . (b) ______ kg of carnivores.
Ecosystem 3.25
9. Pyramid of ______ is always upright. 4. Which one of following is an abiotic

10. Tropical forests occurs in India in component of the ecosystem?
______ . (a) Plants (b) Bacteria
11. The tundra biome occurs in ______ . (c) Fungi (d) Humus
12. The concept of ______ was 5. Which one is the correct food chain?
introduced by Charles Elton. (a) Phytoplankton Æ zooplankton
Æ fish
II. Match the following terms.
(b) Fish Æ zooplankton Æ phyto-
Match the terms of column I with
plankton
appropriate terms of column II.
(c) Zooplankton Æ phytoplankton
A. Æ fish
Column I Column II (d) Phytoplankton Æ fish Æ zoo-
plankton
1. Wetlands (a) African veldt
6. An ecosystem consists of
2. Conifer forests (b) Cactus (a) producers and consumers
3. Tropical rainforests (c) bamboo (b) producers, consumers, decom-
posers, and abiotic environment
4. Desert biome (d) pine
(c) producers and decomposers
5. Grassland (e) swamps (d) consumers and decomposers
B. 7. The main source of energy in an
ecosystem is
Column I Column II (a) mechanical energy
1. Wetland (a) River (b) heat energy
2. Deltas (b) Coral reefs (c) solar energy
(d) chemical energy
3. Ponds (c) seasonal 8. The graphical representation of the
4. Marine ecosystem (d) Fan shaped interrelation of producer and consumer
5. Flowing water (e) Paddy field in an ecosystem is termed the
ecosystem (a) food web
(b) trophic levels
III. Multiple Choice Questions (c) ecological niche
1. The most stable ecosystem is (d) ecological pyramid
(a) ocean (b) forest 9. The shape of the pyramid of biomass
(c) desert (d) mountain for a pond or any aquatic ecosystem is
2. Increase in fauna and decrease in (a) inverted (b) linear
flora would be harmful due to increase (c) upright (d) not certain
in 10. The shape of the pyramid of
(a) O2 (b) CO2 numbers for a parasitic food chain is
(c) N2 (d) S (a) linear (b) inverted
3. The food chain in which micro- (c) upright (d) Not certain
organisms breakdown dead producers 11. The importance of an ecosystem
is called lies in the
(a) Predator food chain (a) flow of energy
(b) Consumer food chain (b) cycling of materials
(c) Detritus food chain (c) both (a) and (b)
(d) Parasitic food chain (d) none of (a) and (b)
12. The food chain in an ecosystem 2. Temperature affects the morphol-

helps to maintain ogy, physiology and biochemistry of
(a) flow of energy in the ecosystem flora and fauna. True/False
(b) passage of nutrients in the eco- 3. The most important function of an
system ecosystem is gas regulation. True/False
(c) the feeding relationship in na- 4. Inorganic molecules do have C-C
ture, thus biodiversity and C-H bonds. True/False
(d) all of the above 5. The most abundant element present
13. The interdependence of the living both in humans and the ecosphere is
organisms among themselves and with oxygen. True/False
the environment is called 6. Grass Æ Mouse Æ Snake Æ Eagle is
(a) ecosystem (b) ecology a typical food chain. True/False
(c) chemistry (d) biology 7. Phytoplankton Æ zooplankton Æ
14. Ecosystem consists of small fish Æ large fish Æ Bacteria is a
(a) abiotic components typical food chain in pond ecosystem.
(b) biotic and abiotic components True/False
(c) biotic components 8. An ecosystem is defined as a natural
unit that consists of living and non-
(d) none of the above
living parts which interact to form a
IV. Indicate True or False for the stable system. True/False
following statements: 9. A food chain is just a sequence of
1. Green plants make high-potential- organisms, in which each is food for the
energy organic molecules from low- next. True/False
potential-energy raw material. 10. The dry weight of all the matter
True/False contained in organisms is known as
biomass. True/False

I. Fill in the Blanks II. Matching the terms
1. primary A. 1. (e) 2. (d) 3. (c) 4. (b) 5. (a)
2. phytoplankton B. 1. (e) 2. (d) 3. (c) 4. (b) 5. (a)
3. detritus
III. Multiple Choice Questions
4 trophic level
1. (a) 2. (b) 3. (c) 4. (d)
5. producer
5. (a) 6. (b) 7. (c) 8. (d)
6. oxygen
9. (a) 10. (b) 11. (c) 12. (d)
7. 200
13. (a) 14. (b)
8. (a) 100, (b) 10
9. energy IV. True or False
10 Kerala and Assam 1. True 2. True 3. False 4. False
11. Arctic zone 5. True 6. True 7. True 8. True
12. Ecological pyramids 9. True 10. True
4
BIODIVERSITY AND
ITS CONSERVATION
Learning Objectives
∑ define biodiversity and its conservation
∑ explain genetic diversity, species diversity and ecosystem diversity
∑ enumerate different biogeographic zones of India
∑ discuss the issues of food security and shelter security
∑ explain the major world food problems
∑ discuss the issues of social and economic security
∑ describe the rare species and threatened species
∑ explain poaching of wildlife
4.1 BIODIVERSITY
Diversity means the number and variety of species. Biodiversity is the diversity of
plant and animal life in a particular region or in the world as a whole. It is often
used as a measure of the health of biological systems. The year 2010 was declared as
the International Year of Biodiversity.
Biodiversity represents the quality and characteristic features of life in an eco-
system. Being a combination of genes, species and the ecosystem itself, biodiversity
can be considered at three levels: genetic diversity; species diversity and ecosystem
diversity. These are briefly explained below.
4.1.1 Genetic Diversity

Living things contain in their cells, the basic instructions (which are called genes) for
their own development. Many of these instructions result in physical characteristics
that affect the way organisms interact with their environment. Variations in such
characteristics within the same species give rise to genetic diversity. A significant level
of variation must be present for a species to adapt to an ever-changing ecosystem.
Domesticated species often have low levels of genetic diversity posing risks. A newly
evolved virus or bacteria strand can invade a population of nearly identical organ-
isms very rapidly. Thus, the protection that genetic diversity generally offers in wild
populations is lost in such artificial selection or preferential breeding of crops and
animals.
4.1.2 Species Diversity

It is a measure of the diversity within an ecological community that incorporates the
number of species in a community and the evenness of species abundances.
Communities with more species are considered to be more diverse. Evenness
measures the variation in the abundance of individuals per species within a
community. Communities with greater evenness are considered to have greater
species diversity.
(a) Species Richness Number of species per unit area
(b) Species Evenness Evenness of individuals in a species
Table 4.1 Species richness and evenness

Region I Region II Remarks
Fishes of Type A 5 20 Region II has more species richness and
Fishes of Type B 10 20 species evenness, so it is more diverse than
Fishes of Type C 15 20 region I.
Fishes of Type D 20 20
Evolution of Diverse Species in an Ecosystem Tropical ecosystems (like

rainforests and coral reefs) are more biodiverse. Two or three times as many species
live in the tropical ecosystems as live in temperate regions—and perhaps ten times
as many species live in the tropics as live in the arctic.
Ecosystems near the equator have more species than do ecosystems nearer the
poles. The tropics have been a diversity hot spot for more than 250 million years.
This is because the tropics appear to be both cradles and museums of diversity.
As per biologists, diversity in a particular ecosystem is a result of local origination
processes, local extinction processes and immigration processes,
[Diversity = Origination – Extinction + Immigration]

Thus, the tropics have high diversity because they have high origination, low
extinction, high immigration or some combination of these processes.
To sum up, species diversity provides a quantitative idea of the number of species
and the variety of species present in a particular region.
(i) Cradle of diversity means areas where new species are born and nurtured.
(ii) Museum of diversity means areas where old species are preserved despite
having gone extinct in the rest of the world.
(iii) Local origination is a process which adds to diversity by generating new
lineages. (Lineages means a series of organisms, populations, cells connected
by ancestor/descendent relationships. It also means ancestry or family.)
(iv) Local extinction is a process which removes diversity by wiping lineages out
in a particular area.
(v) Immigration is a process which adds to diversity through new migrant
lineages from other areas.
Biodiversity and its Conservation 4.3
4.1.3 Ecosystem Diversity

It indicates the variation in the structure and functions of ecosystems. It tells about
trophic levels, energy flow, food and total stability of ecosystems. The ecosystems
can be of various types as governed by the species composition and the physical
structure. Following are a few examples:
(i) Terrestrial ecosystems
(ii) Aquatic ecosystems
(iii) Artificial or man-made ecosystems
4.2 VALUES OR BENEFITS OF BIODIVERSITY

Ecosystems and the species living in them are of enormous value to humankind.
Benefits offered by biodiversity are briefly discussed below:
(i) Intrinsic Values Whenever something has a value for its own sake, we
say, it has intrinsic value. It means, it does not have to be useful to humans
to possess that value. For example, animals and plants have unique intrinsic
value attached to them.
(ii) Agricultural Values Apart from wheat, maize and rice which fulfill about
60% of global food demands, thousands of plant species existing in nature
could be utilised by humans as food.
(iii) Medicinal Values According to the World Health Organization, 80
percent of the world’s people depend on natural-product-based medicine
for healthy life.
(iv) Pest Control Values Selected species from nature have very important uses
for controlling pests. For this, gene bank or natural biota must be preserved.
(v) Recreational and Aesthetic Values People enjoy fishing, camping, and
other wildlife-related recreation activities. Contact with nature is ecologically
and emotionally restorative.
(vi) Instrumental Values A species or individual organism has instrumental
value if its existence or use benefits some other entity. Millions of people
draw sustenance and income directly from forests, grasslands and fisheries.
(vii) Nonconsumptive Values Soil formation and protection of soil from
erosion, carbon fixing through photosynthesis, etc., are a number of values
that have a very important role in providing suitable conditions for living
organisms.
(viii) Consumptive and Productive Values Fruits, vegetables, beverages and a
wide array of food products are derived from biodiversity as they originate
from living environment.
Medicines, fertilisers, fibres, rubbers and a number of other products
obtained from or derived from the living environment have consumptive
and productive values.
(ix) Ecological Values Solar energy absorption, nutrient cycling, air and water
purification, soil formation, food production, waste disposal and a number
of other ecological services depend on biodiversity. They are all very essential
for humans, animals, plants, etc.
Fig. 4.1 Values of biodiversity
4.3 BIOGEOGRAPHIC ZONES OF INDIA

For the planning of conservation of biodiversity at the state and national levels,
classification of ecosystems is done based on biogeography.
The biogeographical classification uses the following four levels of planning:
(a) Biogeographic Zone It is a large distinctive unit of similar ecology, biome
representation, community and species, e.g. the coasts, the islands, etc.
(b) Biotic Province It is the secondary unit within a biogeographic zone,
giving weight to particular community.
(c) Land Region It is a tertiary set of units within a province. It indicates
different landforms.
(d) Biome It is an ecological unit and is found in biogeographic zones or provinces.
Explanation of Characteristics of Biogeographic Zones of India
A concise description of major biogeographic zones is outlined below:
(i) Trans-Himalayan Zone Climate is cold, vegetation is mountain type,
animals found are sheep, goats and snow leopards.
Siachin, Leh and Srinagar are important places of this zone.
(ii) Himalayan Zones East, west, central and north-west Himalayas are the
four biotic provinces of this zone. It has three climate zones and three vegeta-
tion zones. Elephants, apes, tigers, lions and bears, are main animals of this zone.
Arunachal Pradesh, and Jammu and Kashmir are important places of this
zone.
(iii) North-East India Climate is highly moist because of heavy rainfall.
Bamboo, citrus plants and banana, are important vegetation of this zone.
The elephant is the main animal of this zone.
Cherrapunji, Imphal, and Shillong are important places of this zone.
(iv) North-West Desert Zone Summer is very hot and dry; winter is cold;
rainfall is less. Ground vegetation and grasses are the main vegetation of
this zone. The Indian Bustard (highly endangered species) is the surviving
animal in this zone.
Jodhpur and Jaisalmer are important places of this zone.
(v) Gangetic Plain Moderate temperature and moderate rainfall is the char-
acteristic climate. Many species of grasses, ground vegetables, fruits and
flowering plants are found in this zone. Tigers, leopards, monkeys, apes and
elephants are the main animals of this zone.
Lucknow, Allahabad, Patna and Kolkata are important places of this zone.
(vi) Semi-Arid Zone Moderate rainfall and temperature is the characteristic cli-
mate. Mixed deciduous, thorny and sal type of forests are found in this zone.
Indore, Bilaspur, Jabalpur and Sambalpur are important places of this zone.
(vii) Deccan Penninsula Zone In this zone, the average annual rainfall is low.
This zone extends from central India to south India.
Raipur, Hyderabad and Bangalore are important places of this zone.
(viii) Eastern and Western Sea Coasts In this zone, the climate is neither too
hot nor too cold. Mangroves (estuarine ecosystem) are found in this zone.
Thiruvanantpuram, Chennai and Mumbai are located in this zone.
(ix) Western Ghat Zone Rainfall is heavy, climate is neither too hot nor too
cold. Different types of forests, viz. tropical moist evergreen, mangrove,
mixed deciduous and temperate evergreen type, are found in this zone.
Pune and Surat are located in this zone.
(x) Islands Zone Climate is moist, neither too cold nor too hot.
Mangroves, beach forests and forests of tall trees are found in this zone.
Port Blair and Kavaratti are located in this zone.
4.4 HOT SPOTS OF BIODIVERSITY

The areas on earth which exhibit high species richness as well as high species endemism
are termed hot spots of biodiversity.
To qualify as a hot spot, an area must satisfy the following criteria:
(i) It must support 0.5% of the global plant species.
(ii) It must have lost more than 70% of its original habitat.
There are 34 hot spots of biodiversity on a global level, out of which the following
are present in India:
(a) The Western Ghats
(b) The Eastern Himalayas
About 1 billion people live in these hot spot areas. Many of these areas also suffer
from overexploitation of land due to excessive agriculture, hunting, logging and
climate changes. Thus, hot spots are in need of sincere conservation actions.
4.5 ENDANGERED AND ENDEMIC SPECIES

(i) Endemic species can be defined as those species that have very restricted
distribution and are confined over relatively small ranges.
Examples: Lion-tailed Macaque, Nilgiri leaf monkey.
(ii) When there is no reasonable doubt that the last individual has died, the
species is said to be extinct.
(iii) A species is extinct in the wild when exhaustic surveys in habitats have failed
to record an individual.
(iv) A species is critically endangered when it is facing an extremely high risk of
extinction in the wild in the immediate future.
(v) A species is endangered when it is not critically endangered but is facing a
high risk of extinction in the wild in the near future.
(vi) A species is vulnerable when it is not critically endangered or endangered,

but is facing a high risk of extinction in the wild in the near future.
Endangered species are provided with legal protection because their population
decreases very rapidly. Examples: Tiger, Asian elephant, etc.
4.6 RARE AND THREATENED SPECIES

Rare species, although are not vulnerable or endangered, have a very small population
in the world.
Threatened species are those species which may become extinct if not protected.
They include the rare, vulnerable and endangered species.
Examples Elephant, chinkara, Nilgiri tahr, Indian wild ass, lion-tailed macaque,
tiger, cheetah, sloth bear, rhinoceros, etc.
4.7 THREATS TO BIODIVERSITY

In the last 150 years, the rate at which
species are disappearing is about
thousands per decade; while the natu-
ral extinction rate is only one or two
species per decade. Fig. 4.2 Threats to biodiversity
Some of the main causes are as follows:
(i) Degradation of Habitat A habitat is place where living beings find food,
cloth and shelter and a safe place to reproduce and bring up their offspring.
Thus, loss of habitat is the greatest threat to the world.
(ii) Overexploitation of Resources A number of species like tigers, giant pan-
das, etc., are on the verge of extinction because of overexploitation of resources.
(iii) Pollution Pollution is responsible for global climatic changes and for the
extinction of most species.
(iv) Extinction of Weaker Species due to Aggressive Non-native Species It
is responsible for extinction of almost 50% of species on islands all over the
world since 1800 AD.
(v) Poaching of Wildlife Poaching is the illegal killing of wildlife for sale in
the international trade market. The animals are killed due to the following
reasons.
∑ Some wildlife species are killed for consumption (eating).
∑ Elephants are killed to obtain their teeth for financial gains.
∑ Tigers/lions are killed to extract their skin to be sold for decoration of
drawing rooms of some people.
We can stop poaching and conserve wildlife by
(a) Reporting poaching incidents to the concerned officers
(b) Encouraging effective wildlife legislation, and law enforcement
(c) Spreading awareness about the importance of wildlife
(d) Refusing to purchase products that have been illegally obtained from animals
4.8 HUMAN–WILDLIFE CONFLICTS

Human–wildlife conflict occurs when wildlife requirements overlap with those of
humans, creating loss to both.
(i) Consequence of the Human–Wildlife Conflicts The conflicts has
important consequences in terms of
(a) Wildlife conservation
(b) Micro and macro economy
(c) Safety and well-being for local population
(d) Food security
(ii) Reasons of Human–Wildlife Conflicts High human population growth
rate which results in increasing demand for natural resources and the growing
pressure for access to land.
Is there a human–wildlife animal conflict in the area?
Yes No
Is the problem is in No action necessary

conservation area?
No Yes
Can wildlife be managed in (i) Implement community

the area so that benefits awareness and protection strategies
are greater? (ii) Remove problem causing wildlife
animals or humans
No Yes
Can land use be planned (I) Develop and implement plans to sustainably
to cost-effectively manage wildlife in the area
accommodate wildlife? (ii) Implement community awareness and
protection strategies
(iii) Remove problem-causing wildlife animal
or humans
No Yes (iv) Monitor
Remove wildlife
Fig. 4.3 A decision support process to determine appropriate
management actions in areas with human conflict
4.9 CONSERVATION OF BIODIVERSITY

(A) Aims The protection, preservation, management or restoration of natural
resources.
(B) Objectives As per the Ministry of Environment and Forests, Government

of India, the objectives of conservation of biodiversity are
(i) To protect all critically endangered, endangered, and rare species
(ii) To protect natural habitats for preserving all varieties of old and new flora,
fauna and microbes
(iii) To increase public awareness through media, government agencies, NGOs,
etc, and implement strict restrictions on export of rare plants and animals
(iv) To reduce pollution
(v) To maintain ecological balance
(vi) To utilise the natural resources in a sustainable way
Fig. 4.4 Objectives of conservation of biodiversity

(C) Types
Conservation of biodiversity can be carried out in the following ways:
(i) In-situ Conservation It is the conservation of ecosystems and natural
habitats, and the maintenance and recovery of viable populations of species in their
natural surroundings, and in the case of domesticated or cultivated species, in the
surroundings where they have developed their distinctive properties.
(a) Advantages Convenient and economical way as only supportive role is
being played.
(b) Disadvantages It requires a large area for the complete protection of
biodiversity. It implies a restriction of human activity and a greater interaction
of wildlife with local residents near a reserve forest.
Fig. 4.5 Illustration of conservation methods of biodiversity

(ii) Ex-situ Conservation It is the conservation of components of biological
diversity outside their natural habitats. It is applicable for those threatened or
endangered species whose population is so fragile and habitat fragmented that their
survival in the wild is no longer possible.
Suitable locations for ex-situ conservation of animals and plants are zoological
parks, and botanical gardens respectively.
∑ Diversity means the number and variety of species. Biodiversity is the diversity of plant
and animal life in a particular region or in the world as a whole.
∑ Living things contain in their cells, the basic instructions (which are called genes) for
their own development. Many of these instructions result in physical characteristics
that affect the way organisms interact with their environment. Variations in such char-
acteristics within the same species give rise to genetic diversity.
∑ Species diversity is a measure of the diversity within an ecological community that
incorporates the number of species in a community and the evenness of species
abundances.
(a) Species Richness: Number of species per unit area
(b) Species Evenness: Evenness of individuals in a species
∑ Ecosystem diversity indicates the variation in the structure and functions of ecosystems.
It tells about trophic levels, energy flow, food and total stability of ecosystems.
∑ Biogeographic zone is a large distinctive unit of similar ecology, biome representation,
community and species, e.g. the coasts, the islands, etc.
∑ Biotic province is the secondary unit within a biogeographic zone, giving weight to
particular community.
∑ Land region is a tertiary set of units within a province. It indicates different
landforms.
∑ Biome is an ecological unit and is found in biogeographic zones or provinces.
∑ Endemic species can be defined as those species that have very restricted distribution
and are confined over relatively small ranges.
∑ When there is no reasonable doubt that the last individual has died, the species is said
to be extinct.
∑ A species is extinct in the wild when exhaustic surveys in habitats, have failed to record
an individual.
∑ A species is critically endangered when it is facing an extremely high risk of extinction
in the wild in the immediate future.
∑ A species is endangered when it is not critically endangered but is facing a high risk of
extinction in the wild in the near future.
∑ A species is vulnerable when it is not critically endangered or endangered, but is facing
a high risk of extinction in the wild in the near future.
∑ Rare species, although are not vulnerable or endangered, have a very small population
in the world.
∑ Threatened species are those species which may become extinct if not protected.
∑ Human–wildlife conflict occurs when wildlife requirements overlap with those of
humans, creating loss to both.
∑ In-situ conservation is the conservation of ecosystems and natural habitats, and the
maintenance and recovery of viable populations of species in their natural surroundings,
and in the case of domesticated or cultivated species, in the surroundings where they
have developed their distinctive properties.
∑ Ex-situ conservation is the conservation of components of biological diversity outside
their natural habitats.
EXERCISES
1. Write a brief note on biodiversity 8. What is poaching of wildlife? How
and ecosystem diversity. can it be controlled?
2. Explain the evolution of diverse 9. How do biosphere reserves help in
species in an ecosystem. conservation of biodiversity?
3. What do you understand by the 10. Write a short note on conservation
term ‘biodiversity’? Write briefly about of biodiversity.
the different kinds of diversity in 11. What are national parks?
organisms. 12. What are wildlife sanctuaries?
4. What is biodiversity? Write the 13. What are the differences between
major factors responsible for the loss endangered species and endemic
of genetic biodiversity. How can it be species?
conserved? 14. What are the differences between
5. What are the values of biodiversity? a national park, wildlife sanctuary and
6. What are biodiversity hot spots? reserve forest?
7. What are endemic species? Name 15. What is the difference between in-
some endemic species of India. situ and ex-situ conservation?

I. Fill in the blanks thangal, kaundinya, Chilka lake, Ma-
1. Biodiversity refers to the totality yani, Nal Sarovar are the top 10 famous
of genes, species and _______ of a _______ Sanctuaries of India.
region. 8. _______ is the largest wildlife
2. Biodiversity increase from the poles sanctuary of India.
to the _______ . 9. _______ is the illegal killing of
3. Within a community, diversity is wildlife for sale in the international
called _______ . trade market.
4. Western Ghats and _______ in India 10. The areas on earth which exhibit
are among the 25 global biodiversity high species richness as well as high
hot spots. species endemism are termed _______
5. As per the latest (2011) quantitative of biodiversity.
evaluation done by the International 11. Biodiversity is the term popularised
union for conservation of Nature (IUCN), by the sociobiologist _______ .
there are _______ critically endangered 12. Biodiversity is the foundation of
species of animals in India. healthy, functioning _______ upon
6. Sacred _______ and lakes are which all life depends.
traditional protected areas. II. Match the following terms.
7. Bharatput, Sultanpur Salim Ali, Match the terms of column I with
Kumarakom, Ranganthittu, Vedan- appropriate terms of column II
A. 3. Variation of genes within the same

Column I Column II species is
1. Pink head duck (a) Endangered (a) species diversity
(b) genetic diversity
2. Himalayan brown (b) Vulnerable
(c) biodiversity
bear
(d) ecosystem diversity
3. Andaman wild pig (c) Endemic 4. The variety and the number of living
4. Asiatic elephant (d) Rare organisms present in an ecosystem is
5. Black buck (e) Extinct called
B. (a) bioprospecting
Column I Column II (b) biopiracy
(c) biodiversity
1. Reserved (a) Forests are regarded
(d) biogeography
forests as most valuable for the
5. Which of the following animals is
conservation of forest
endemic to India?
and wild life resources
(a) Blue whale
2. Protect- (b) Forestlands are pro- (b) Snow leopard
ed forests tected from any further (c) Asian elephant
depletion. (d) Red colobus monkey
3. Un- (c) Other forests and 6. Which of the following is a biodiver-
classed wastelands belonging sity hot spot in India?
forests to both government (a) Sundland
and private individuals (b) Eastern Himalayas
and communities (c) Succulent karoo
C. (d) Mediterranean basin
Column I Column II 7. Which of the following is an in-situ
tiger reserve in India?
1. Black soil (a) Tropical forests
(a) Gulf of Myanmar
2. Arid zone (b) Dwarfed plants
(b) Western Ghats
3. Habitat loss (c) Fragmentation (c) Dudhwa
4. Alpine zone (d) Punjab (d) Agasthyamalai
5. Malabar region (e) Deccan platean 8. Which of the following is not a world
heritage site of India?
III. Multiple choice Questions
(a) Manas Wildlife Sanctuary
1. A biosphere reserve normally con-
(b) Kaziranga National Park
sists of
(c) Sundarbans National Park
(a) one or several core zones
(d) Simplipal
(b) a buffer zone
9. Which of the following is an endemic
(c) a transition zone
species found in Western Ghats, India?
(d) all of the above
(a) Brown Palm Civet
2. Extinction of a weaker species by an
(b) Marsh Mongoose
aggressive alien species is the result of
(c) Indian Rhinoceros
(a) the domino effect
(d) Flying squirrel
(b) habitat loss
10. The concept of biodiversity hot
(c) endemism of weaker species
spots was penned by the British
(d) all of the above.
ecologist
(a) F.P. Odum 2. New approach to conservation is the

(b) Norman Myers establishment of biosphere reserves.
(c) James Lovelock True/False
(d) Rachel Carson 3. The Tibetan antelopes chiru are
11. The major threat to biodiversity is killed for their wool, which is woven into
due to the luxuary fabric shantoosh, threaten-
(a) habitat loss (b) pollution ing species survival. True/False
(c) global climatic changes 4. The dodo (bird) was first sighted
(d) all of the above around 1600 on Mauritius, an island in
12. Species with very restricted distri- the Indian ocean. The dodo was extinct
bution over relatively small ranges is less than eighty years later. True/False
called 5. The Indian bustard or the great
(a) extinct species Indian bustard is a large bird with a
(b) endangered species horizontal body and long bare legs,
(c) endemic species being critically endangered by hunting
(d) none of the above and loss of its habitat. True/False
13. Biodiversity hot spots are also 6. If all the plants of the earth die
known as suddenly, all the animals will die due to
(a) forest areas (b) desert areas deficiency of oxygen. True/False
(c) land areas 7. The biogeographic zone is a large
(b) biologically rich areas with large distinctive unit of similar ecology,
percentage of endemic species. biome representation, community and
species. True/False
IV Indicate True or False for the
8. Biodiversity is the diversity of plant
following statements:
and animal life in a particular region or
1. Animals and plants are best protect-
in the world as a whole. True/False
ed in national parks. True/False

I. Fill in the blanks II. Matching the following terms
1. ecosystem A. 1. (e) 2. (d) 3. (c) 4. (b) 5. (a)
2. equator B. 1. (a) 2. (b) 3. (c)
3. alpha diversity C. 1. (e) 2. (d) 3. (c) 4. (b) 5. (a)
4. Eastern Himalayas
5. 57 III. Multiple Choice Questions
6. groves 1. (d) 2. (a) 3. (b) 4. (c)
7. Bird 5. (a) 6. (b) 7. (c) 8. (d)
9. (a) 10. (b) 11. (d) 12.(c)
8. Sunderbans, West Bengal
9. Poaching 13. (d)
10. hot spots IV. True or False
11. Edward Wilson 1. True 2. True 3. True 4.True
12 ecosystems 5. True 6. True 7. True 8. True
5
ENVIRONMENTAL
POLLUTION AND ITS
EFFECTS
Learning Objectives
∑ explain the meaning of environmental pollution, water pollution, land
pollution, noise pollution and air pollution
∑ describe the requirement of a nonpolluted environment
∑ identify the importance of efforts at individual levels to prevent
environmental pollution
∑ describe the natural and man-made (synthetic) pollutant that cause air
pollution
∑ suggest various remedial and control measures to minimise water
pollution
∑ discuss the causes of land pollution and its control
∑ explain how industrial, agroproducts and pesticides deteriorate the soil
∑ describe the effects of air pollution on human health
∑ describe the measures used for controlling air pollution
∑ define what are solid wastes
∑ explain the various methods commonly employed for disposal of solid
waste with their advantages and disadvantages
∑ describe the idea of solid waste management
5.1 INTRODUCTION
(i) Environment It is made up of air, water, land and biota. It is virtually
everything that surrounds an organism. The surroundings may be living or nonliving.
Each living organism constantly interacts with its environment and adapts to it.
(ii) Pollutant It is a material which is present in excess of the natural concentration
and produces a bad effect upon the environment. For example, fertilisers having
nitrates in them are added so as to increase plant growth. But an excessive nitrate
concentration present in drinking water can be toxic, especially to children.
Thus, anything or any substance, if present in undesirable concentrations and in the
wrong place at the wrong time is a pollutant.
(iii) Source It is the system (material or activity) which releases the pollutant.
(iv) Receptor It is something that is affected by the pollutant.

(v) Sink It is the store where the pollutant is received and stored for a long time.
(vi) Pollution or Environmental Pollution It can be defined as an undesirable
change in the physical, chemical or biological characteristics of our environment by the
introduction of substances or energy by humans into the environment.
Environmental pollution is liable to cause hazards to human health, harm to
living resources, damage to structures, interfere with legitimate uses of environment
and/or harm to ecological systems.
(vii) Environmental Pollution
Process In it, a pollutant origi-
nates from a source. It gets trans-
ported by air or water or is dumped
on land by humans. Some of the
pollutant is assimilated (adsorbed)
or chemically changed by the envi-
ronment. The remaining pollutant
builds up to concentrations which
are harmful to the environment
(Fig. 5.1). Fig. 5.1 Environmental pollution process
5.2 REQUIREMENTS OF A NONPOLLUTED

ENVIRONMENT
For the survival of humans, the requirements are air, water, food, shelter, forests
and energy.
5.2.1 Harms of Polluted Environment

(i) Air Air quality is deteriorating day by day. Outdoor air pollution, whether in
the form of visible haze or invisible ozone, and carbon monoxide, is a problem for
nearly every country in the world.
Current emission of carbon dioxide is about 30 billion metric tons per year. It is
expected to increase to around 60 billion metric tons per year by the middle of the
century. In order to achieve climate stabilisation, an emission-reduction target of
50% to 100% by 2050 is needed from today’s levels.
Indoor air pollution is the second leading environmental health threat in the
world. It causes 1.6 million premature deaths every year and afflicts nearly half of
the world’s population, predominantly the rural poor. Indoor air pollution occurs
in poor ventilation systems with accumulations of all sorts of contaminants and
toxic substances in the air.
(ii) Water Without clean and usable water, nothing can survive. Global water
consumption increased sixfold in the last century—more than twice the rate of
population growth. Yet readily available fresh water is a finite resource. Moreover,
water and populations are unevenly distributed across the globe. Arid and
Environmental Pollution and its Effects 5.3
semi-arid regions receive only two per cent of all surface run off yet account for
40% of the global land area and about 50% of the world’s poor live there. The
existing freshwater resources are under heavy threat from overexploitation, pollution
and climate change. There are 74 different kinds of pesticides which have been
found in groundwater, used today as potential drinking water. Given these trends,
equitably providing adequate water resources for agriculture, industry and human
consumption is one of the biggest challenges of the 21st century.
(iii) Food The United Nations estimates that agricultural output will have to rise
50% by 2030 to meet the increasing demand for food, because of
(a) Continued increase in the world’s population
(b) Increased wealth generation from economic development
(c) Production of biofuels from food crops like corn and sugarcane
We have observed record-setting harvests over the last few years, and yet chronic
hunger persists and has recently been increasing.
(iv) Shelter Cities are home to half of the world’s people. They are the hot spots
of consumption, production, and waste generation.
However, 50% of the world’s people are poor, facing hunger and illness. Thus,
sustainable development needs to be the focus area. It supports the concept of lifting
populations out of poverty without endangering resources and the environment
for future generations. At present, poor populations are suffering from the effects
of unsustainable energy use such as adverse health impacts, deforestation, climate
change and desertification.
(v) Forests Forests contain 70% of the world’s biodiversity, provide vital
ecosystem services such as soil protection and flood control, and support the
subsistence livelihoods of up to 300 million poor people.
Between 2000 and 2005, roughly 13 million hectares of forest disappeared each
year, mainly from the biologically rich tropical forests of the developing world. The
intergovernmental panel on climate change estimated that deforestation contributes
15–20 per cent of global greenhouse gas emissions in 2007.
(vi) Energy On a yearly basis, just in the United States, power plants (that
generate electricity), cause 3500 lung-cancer cases and over 35000 heart attacks.
The situation is worse in underdeveloped or poor countries where the industrial and
the private sectors do not follow consistent environment-protection guidelines.
5.2.2 Benefits of Nonpolluted Environment

A nonpolluted environment provides us clean air and water, generates less waste and
helps in the conservation of habitat and biodiversity. The economic benefits include
reduced expenses on health care, conveyance, and water and electricity bills.
5.3 PUBLIC HEALTH ASPECTS

Health is an outcome of the interactions between people and their environment.
Disturbance of ecosystems and natural cycles, resource depletion, waste generation
and pollution of natural resources affects human health.
Common cold, influenza, chicken pox, tuberculosis, silicosis, gout, black lung
cancer, bronchitis and asthma are diseases caused by air pollution.
Cholera, typhoid, dysentery, minamata disease, hepatitis, intestinal disorders are
diseases caused by water pollution.
Bolutism, viral food poisoning, fungal food poisoning, staphylococcal poisoning
are food-borne diseases.
Teeth/gum diseases, rickets/osteomalacia, anaemia and avitaminosis are deficiency
diseases.
Cancer is caused by harmful environmental exposure, tobacco smoking and alcohol
consumption.
The key to attaining a good health is based on proper nutrition, safe drinking
water availability, provision of maternal and child health care, immunisation against
the major infectious diseases, prevention and control of locally endemic diseases,
etc. (Fig. 5.2).
Characteristics of a healthy person are
(i) Absence of physical discomfort,
(ii) Cheerfulness,
(iii) Courage to face reality,
(iv) Enthusiastic and efficient ability
to work,
(v) Self-control and self-confidence,
(vi) Stable mental attitude,
(vii) Efficiency, and Fig. 5.2 Important factors for
(viii) Freedom from disease. attainment of good health
Memory aid
“A C C E S S E D”
5.4 AIR POLLUTION

Air pollution is the presence of substances in the air (which generally originate from
human activities) in sufficient concentrations and sufficient time, to interfere with the
comfort, health, safety or full use and enjoyment of property.
5.4.1 Sources of Air Pollution

(i) Point Sources These are sources which cause direct release of air
pollutants.
Example The emission of gases from an industry through a chimney.
(ii) Nonpoint Sources These are sources which release substances which are ca-
pable of undergoing chemical reactions in the atmosphere to generate air pollutants.
Example Photochemical smog
(iii) Man-made or Anthropogenic Sources These are sources which generate
air pollutants by human activities.
Examples Vehicular discharges, burning of fossil fuels, population explosion, etc.

∑ Vehicular Discharges A mixture of CO, CO2, NOx and RH are emitted as
exhaust gases from automobiles. They cause air pollution as such. Moreover,
they also react with oxides of nitrogen in the presence of sunlight to produce
highly toxic photochemical smog.
∑ Burning of Conventional Fossil Fuels Burning of coal, lignite, natural gas
and combustion of petrol/diesel/CNG produces gaseous by-products like
CO, SO2 NOx which are toxic. They pollute the air and make it unfit for
breathing.
∑ Population Explosion It creates the emission of greenhouse gases, global
warming, destruction and loss of forest cover and wildlife, etc.
The classification of air-pollution sources is summarised in Fig. 5.3.
Fig. 5.3 Classification of air-pollution sources
5.4.2 Air Pollutants

Air pollutants are gaseous, liquid or solid substances present in such concentration as
may be or tend to be injurious to human beings or other living creatures or plants or the
environment.
(A) Classification of Air Pollutants The air pollutants can be classified in
the following three ways:
Fig. 5.4 Classification of air pollutants

(B) Air Pollutants for which National Ambient Air Quality Standards
have been given in India The Central Pollution Prevention and Control
Board, New Delhi, has provided the standard for ambient air quality in India under
the Act of 1981. Table 5.1 lists these standards.
The air-quality standards give the maximum limit of a particular pollutant
permitted in the air around us (i.e. ambient air).
Table 5.1 Ambient air-quality standards in India [Concentration mg/m3]
Area Type SO2 CO NOx SPM
(i) Sensitive areas like places with monu- 30 1000 30 100
ments, sanctuaries, tourist resorts
(ii) Residential and rural areas 80 2000 50 200
(iii) Industrial and mixed use areas 120 5000 120 500
(C) Natural and Man-made (Synthetic) Air Pollutants and their

Consequences
(i) Carbon Monoxide (CO)
Sources Forest fires, agricultural burning, incomplete combustion of fuels, tobacco
smoking, automobile exhausts, etc.
Effects Toxicity, blood poisoning leading to death, increased proneness to
accidents.
(ii) Sulphur Dioxide (SO2)
Sources Combustion of coal and petroleum products, sulphuric acid plants,
powerhouses, metallurgical operations.
Fig. 5.5 Sources of air pollutants and their environment effects

Effects Irritation of throat and eyes, suffocation, aggravation of asthma and

chronic bronchitis.
(iii) Oxides of Nitrogen (NOx)
Sources Nitric acid plants, automobile exhausts, explosives and fertiliser industries,
power stations.
Effects Headache, respiratory irritation, impairment of lung defences, corrosion
of teeth, loss of appetite.
(iv) Mercury (Hg)
Sources Mining and refining of Hg, industries linked with manufacture of
medicinal products, pesticides which use organic mercurials.
Effects Inhalation of Hg vapours cause toxic effects, highly toxic organo-mercurials
may cause irreversible damage to brain and nervous system.
(v) Lead (Pb)
Sources Automobile emissions, electroplating waste, plumbing, lead paint
industry, printing, etc.
Effects Liver and kidney damages, mental retardation in children, abnormalities
in fertility and pregnancy, gastrointestinal damage.
5.4.3 Measures Used for Controlling Air Pollution

The most effective method to control air pollution is to prevent the formation of
pollutants or to reduce their emission at the source itself.
Fig. 5.6 Measures to check air pollutants
(i) Source Correction Methods In case of industrial pollutants, the designing

and development of plants may be so selected so as to have minimum emission of
air pollutants.
Examples
(a) By suitable design modification of the tanks, evaporation from petroleum
refineries can be minimised.
(b) Use of correct grade of raw material like low-sulphur oil and coal is
recommended.
(ii) Cleaning of Gaseous Effluents These techniques control pollution by the
removal of pollutants from the exhaust. These methods are used in combination
with source correction methods.
Fig. 5.7 Options for controlling emissions at source
(a) For Gaseous Pollutants The gaseous pollutants are removed by absorption in
a liquid, or adsorption on a solid. Catalytic converters are also used as they convert
gaseous air pollutants into harmless gases.
(b) For Particulates Following techniques are generally used for control of
particulate emissions:
∑ Gravitational settling chambers,
∑ Cyclone separators,
∑ Fabric Filters,
∑ Electrostatic precipitators, and
∑ Wet scrubber, etc.
Case Studies
(i) Health Impact of Vehicular Pollution
During 2007–2010, a cross-sectional study was carried out to investigate the
health impact of vehicular pollution in Kolkata (India). This study was done
among 932 male nonsmoking residents of Kolkata city and 812 age- and gender-
matched rural subjects as control. The urban group included 56 motor mechanics,
78 bus drivers, 82 autorickshaw drivers, 188 street hawkers, 56 traffic policemen
and 472 office employees compared with the rural control group.
The urban group had increased prevalence of hypertension, chronic
obstructive pulmonary disease, reduced lung function, headache, asthma, and
other respiratory diseases.
In essence, chronic exposure to vehicular pollution of Kolkata
(a) enchances cancer risk in the lungs,
(b) suppresses immunity,
(c) increases blood pressure, and
(d) reduces lung function.
[http: //www.theicct.org/workshops/India 2011/session/mkRey.pdf]
(ii) Indoor Air Pollution People in modern societies often spend many
hours daily in the indoor environment. It is therefore very useful to find out
the contribution of Indoor Air Quality (IAQ) to possible health outcomes at the
household level.
The following important issues were found out based on empirical data
collected from 5949 households from 35 wards of Delhi (NCT of Delhi):
(a) Many residents live in degraded indoor environmental conditions.
(b) The highest risks to health is from
∑ poor ventilation,
∑ exposure to Environmental Tobacco Smoke (ETS).
∑ lack of kitchen, and
∑ use of traditional fuels.
(c) Most prevalent health problems confronted by residents are
∑ cardiovascular diseases,
∑ lung cancer,
∑ asthma, and
∑ accute respiratory infections.
[http: //onlinelibrary.wiley.com/doi/10.1111/j.1600-0608.2011.0715.x/Full]
5.5 WATER POLLUTION

Pure water, like fresh air, is also becoming a scarcity. Whenever water has a bad taste
or odour; oil or grease is seen floating on the surface of water; occurrence of outbreak
of an epidemic happens; reduction in the number of fishes in water bodies is noticed;
or offensive odours are emitted by water bodies, we say that the water is polluted.
Water pollution is defined as presence of any foreign substance or energy in water
in such concentration and for such duration that tends to degrade the quality of water
so that humans, animals or any other organism cannot enjoy the beneficial qualities of
water but the use constitutes a hazard.
Water pollution is classified as freshwater pollution (it includes both surface and
ground water pollution) and marine water pollution.
5.5.1 Sources of Water Pollution

(i) Point Sources When the cause and place of pollution is easily identifiable, it
is known as a point source of water pollution.
Examples Municipal and industrial discharge pipes.
(ii) Nonpoint Sources When the cause and place of pollution cannot be readily
identified, it is known as a nonpoint source of water pollution.
Examples Mining runoff and acid rain.
5.5.2 Water Pollutants

(i) Organic Pollutants They include oil, synthetic organic compounds, sewage
and agricultural run-off, disease-causing wastes and oxygen-demanding wastes.
(ii) Inorganic Pollutants They include metals, metal compounds, organometallic
compounds, mineral acids, inorganic salts, etc.
Fig. 5.8 Sources of water pollution
(iii) Suspended Solids and Sediments They comprise of sand, silt and
minerals eroded from the land.
(iv) Radioactive Materials They include radioactive isotopes from nuclear
reactors, nuclear power plants, research, industrial applications, agriculture and
therapeutic as well as diagnostic medical applications.
(v) Thermal Pollution They include discharge of waste heat to water bodies by
thermal and nuclear power plants.
5.5.3 Various Remedial and Control Measures to Minimise

Water Pollution
(i) Enforce zero-emissions laws to protect water from pollutants and
contaminants.
(ii) Create strict rules and regulations to prevent the continued pollution of water.
(iii) Conserve clean water supplies.
(iv) Avoid littering in any form.
(v) Support clean agriculture by preferably purchasing and consuming healthy
organic foods. In the growing of organic food, no pesticide or other harmful
contaminants are used.
(vi) Oppose coastal development and preserve natural wetlands, as they serve as
nature’s filter. The vast amount of various plant life, naturally occurring
bacteria and algae and microorganisms help to filter destructive pollutants.
Wetlands can be easily preserved through replanting efforts.
(vii) Create awareness in public through media, child education, etc., for preventing
water pollution.
(viii) Treat waste water (from domestic and industrial houses) before disposal.
(ix) Prevent pollution caused by animals.
(x) Reduce urban/suburban run-off of lawn fertilisers and pesticides—stop use
of chemical pesticides around your house and lawn.
(xi) Contribute some money to replace outdated municipal water-treatment
plants.
(xii) Stop deforestation, save paper. A healthy forest acts like a sponge to soak up
and clean rainwater and then supply it to nearby lakes and rivers.
(xiii) Reduce pollution from oil and petroleum liquids:
(a) Maintain your vehicle more.
(b) Drive your vehicle less.
(xiv) Reduce mercury emissions:
(a) For new coal-fired power plants, use coal-gasification to filter out all
mercury pollution.
(b) For existing coal-fired power plants, use better scrubber technology to
reduce mercury emissions by 90%.
(c) Conserve electricity.
(xv) Insist that regulatory agencies force mining industries to
(a) Use clean technologies for mining operations
(b) Clean up long-abandoned but still-polluting mines
(c) Stop mountaintop removal coal mining practice which often buries
streams together
(xvi) As consumers and citizens, stop purchasing coal, metals, precious metals that
are not produced by environment-friendly techniques.
(xvii) Use only green household cleaners and personal-care products.
(xviii) Fight global warming to avoid ocean acidification and rise in the ocean
temperature.
(xix) Increase tax on chemicals, petroleum products, packaging so as to reduce
their consumption. This helps in preventing water pollution.
(xx) Preferably use solar energy, wind energy, etc., because thermal power plants
use fresh water for producing electricity. By this, fresh water will be available
for other uses.
(xxi) Facilitate soaking of rain through permeable surfaces in parking lots, sports
courts, driveways, sidewalks, etc. Impermeable surfaces increase rainwater
run-off, resulting in more water pollution.
(xxii) Use less plastic bags, as they are easily blown around and end up polluting
water bodies.
(xxiii) Promote industrial symbiosis. In it, the unusable waste from one company’s
industrial process become the input for another’s. It helps in keeping effluents
out of waterways, and keeping solid waste out of landfill.
(xxiv) Promote green chemistry. Eliminate the toxic components of an operation
by using water-based solvents derived from corn, citrus fruits, soybeans and
other biochemical sources.
5.5.4 Water Treatment

Using a network of sewers (i.e. underground pipes), sewage (i.e. waste water) from
residential and commercial areas and industries is collected. This sewage is then
transported through a sewerage system to treatment plants for purification.
Waste-water treatment is carried out in the following steps:
Fig. 5.9 Layout of a water-treatment plant

(i) Primary Treatment It helps in the removal of suspended particles.

(ii) Secondary Treatment It helps in the aerobic decomposition of organic
matter.
(iii) Tertiary Treatment It helps in the production of safe water, free from
harmful chemicals and pathogenic bacteria. Figure 5.9 shows the layout of a water-
treatment plant. The tertiary treatment consists of flocculation, activated carbon,
reverse osmosis and/or chlorination methods to get pure water.
Case Studies
(i) River Water Pollution in India
According to a United Nations report released on March 22, 2010 on World
Water Day:
(a) Contaminated and polluted water kills more people than all forms of
violence including wars.
(b) In developing countries, 90% of waste water discharged daily is untreated.
(c) Sick water (thus obtained) is contributing to the deaths of some 2.2 million
people a year from diarrhoeal diseases.
(d) At least 1.8 million children younger than five years of age die every year
from water-related diseases.
(e) In India, about 80% of urban waste ends up in the country’s rivers.
(f) The river water pollution is getting worse due to unchecked urban growth
across the country combined with poor government oversight.
(g) In India, a growing number of water bodies are not fit for human use.
(h) The River Ganga (holy to India’s 82% Hindu majority) is dying slowly due
to unchecked pollution.
(i) Out of the 15 million Delhi residents, only 55% are connected to Delhi’s
sewage system. The remainder flush their waste, bath waters, etc., down
pipes and into drains, and most of them empty into the Yamuna.
(j) Over 3 billion litres of waste (raw sewage industrial run-off and garbage) is
thrown into the Yamuna river per day.
(k) On various clean-up efforts, nearly 20 billion rupees has been spent
according to the Centre for Science and Environment.
(l) Recently samples taken from the Ganga River (near Varanasi) show that
levels of fecal coliform (a dangerous bacterium that comes from untreated
sewage) were some 3000% higher than what is considered safe for
bathing.
[http: //www.gits4v.com/envo/envo4.htm]
WATER-POLLUTION FACTS
∑ Asian rivers are the most polluted in the world. They have 20 times more
lead than rivers in industrialised countries and three times as many bacteria
from human waste as the global average.
∑ Pollution of freshwater is a problem for about 50% of the world’s

population. Each year there are about 250 million cases of water-related
diseases, with roughly 5 to 10 million deaths.
∑ Each year, plastic waste in water and coastal areas kills up to
1 million sea birds, and 1 lakh marine mammals and countless fish.
∑ In one week, a typical cruise ship generates
(a) > 8 tons of solid waste,
(b) 10 lakh gallons of gray water from showers, sinks, dish washers and
cloth washers,
(c) 2.1 lakh gallons of sewage, and
(d) 37 thousand gallons of oily bilge water.
∑ Around 80% of the pollution in seas and oceans comes from land-based
activities.
∑ In India, almost 70% of surface-water resources have serious pollution
problem.
∑ In India, domestic waste water is one of the major pollution sources.
It causes heavy pollution in 14 major river systems as 50 million m3 of
untreated sewage is discharged into them each year. This also causes high
incidence of water-related diseases.
(ii) Water Pollution in Kolkata

In 2011, engineers of Kolkata Municipal Corporation suggested replacement
of one-third of the total 5000 km pipeline of the water supply network. The
main reason was corroded, age-old, worn-out water pipes. In some stretches,
sewer lines run next to the water pipes. When the pressure in the pipes is low,
often sewage seeps into the water and contaminates it. Because of unsafe drinking
water, Kolkata is facing many health hazards, viz.
(a) Bacterial contamination is causing gastroenteritis, haemorrhage,
septicaemia
(b) Many persons are suffering from irritable bowel syndrome
(c) Contaminated drinking water is also responsible for rapid spread of
hepatitis A and E
(d) Malnutrition and poor growth is also linked to water-borne diseases
[http: //kolkatainfo.wordpress.com/2011/03/14/water pollution in kolkata/]
(iii) Bottled Water
40% of the bottled water industry is branded. Key players are Parle Bisleri, Coca
Cola India Inc., Kinley and Pepsico India Holdings Pvt. Limited. In 2010,
the bottled water market generated $250 million in revenue. Bottled-water
consumption is rising in India due to water shortage and health awareness. It is
to be noted that both tap water and bottled water are unhealthy. The tap water
is legislated to be 7 pH neutral. However, municipalities add huge quantities of
chlorine in the water to kill all harmful bacteria, and this makes it highly acidic
(unhealthy).
Fig. 5.10 Flow chart depicting bottle water cycle

According to a recent study on bottled water, carried out by the Ahmedabad-
based Consumer Education and Research Society (CERS), an independent
nonprofit institution with a sophisticated product-testing laboratory:
(a) In clear violation of norms, as many as 10 of the 13 brands had foreign
floating objects.
(b) Two mineral water units in Bangalore on January 11, 2011 (during a
surprise inspection) were bottling borewell water. They were also illegaly
using several branded labels on the bottles to market the water.
(c) AM Enterprises were found selling water without an ISI mark from the
Bureau of India Standards. They were found mixing mineral water with
borewell water and selling it in cans to the public.
The public is indirectly raising the price of petrol and contributing to global
warming and climate change by purchasing bottled water.
∑ According to a social activist R Srinivasan, more than 13,000 tankers carry
water drawn from farmlands surrounding Chennai so as to generate profit
from Chennai’s accute water scarcity.
∑ According to the Pacific Institute, the manufacturers of plastic water
bottles generated more than 2.5 million tons of carbon dioxide emissions
and required 17 million barrels of oil (in 2007).
∑ About 47 million gallons of oil is required to make plastic bottles for storing
water.
∑ Water when stored in earthen pots, becomes not only refreshingly cool and
tasty, but is said to become bacteria free too.
Beverage majors are all measuring the water consumed for bottling every litre
of their retailed drinks. Efforts to reduce water consumption is necessary for
all companies in India because of limited availability of this natural resource.
Hindustan Coca Cola Beverages uses 2.5 litres of water to make every 1-litre
bottle of the carbonated drink. The company has 56 bottling plants in India.
Coca Cola’s bottling plant in Kerala faced big problems after activists alleged
the company was depleting local water supplies. The Palakkad bottling factory in
Kerala was closed in 2005 after protests from residents and activists. A high-level
state pancel concluded that the Coca Cola plant had caused water contamination,
soil degradation and environmental degradation. They recommended a fine
of 47 million dollars. A bill has been passed on February 25, 2011 allowing
compensation claims in Kerala.
In drougt-prone Kala Dera near Jaipur (India), the focus of the protest is
on the source of the packaged water and how bottling companies are grabbing
underground water. The companies get their water free except for a small
cess (for discharging the waste water). A Rs. 10 per litre bottled water has a
raw material cost of just 0.02–0.03 paise. The companies siphon out, exhaust
and export groundwater that once belonged to an entire village and buy it for
themselves, forcing the villagers to pay for water that they used to be able to use
as a community, free of charge. TERI advised Coca Cola in January to shut a
bottling plant in Kala Dera.
The Tamil Nadu Water Supply and Drainage Board (TWAD) Workers
Federation suggested that the government take over the sale of bottled drinking
water. This is because the actual cost of purifying water is less than 5 paise per
litre. So even if the government sells water at Rs. 2 a litre, they can generate a
revenue of Rs 5,000 crore.
[www.gits4u.com/water/water16.htm]
Hazards of Bottled Water
(i) The global annual amount of plastic used to produce water and carbonated
water bottles is about 3 million tons. Most of this plastic ends up in
landfills.
(ii) Each bottle requires nearly 5 times its volume in water to manufacture,
creating wastage of valuable resource.
(iii) The global annual amount of carbonated bottled water consumed outside
its country of origin is more than 20 million tons. This results in huge
transportation and environmental damage.
(iv) More than 70 per cent of bottles are not recycled. These are responsible for
increased soil pollution as they end up in landfill sites.
(v) The bottled water industry has less stringent testing policies than
governmental agencies which require rigorous testing of tap water. Thus,
bottled water is not safer than tap water.
(Source: www.infographicslibrary.com)
(vi) More than 20% of tested bottled water brands contain chemical
contaminants at levels above strict state health limits
(vii) About 40% of all bottled water is tap water but it is very expensive.
Table 5.2 Comparison of bottled water and tap water
S.No. Attribute Bottled water Tap water
(i) Required to provide source No Yes
(ii) Tested for E.coli bacteria No Yes
(iii) Required to produce quantity reports No Yes
(iv) Can still be distributed when tap water quality Yes No
standards are not met
(Source: www.lifegivingwater.com.au/health.php)
5.6 LAND POLLUTION OR SOIL POLLUTION

Soil pollution can be defined as the introduction of substances, biological organisms, or
energy into the soil that lead to a change in the quality of soil so that plant growth and
animal health is adversely affected.
5.6.1 Causes of Soil/Land Pollution

Soil pollution is caused due to direct and indirect sources. The direct sources
harm the soil much more than the indirect sources. Examples of direct causes
are poor management of solid and liquid domestic/industrial/agricultural
waste, waterlogging, soil erosion, salination, disposal of medical wastes, etc.
Examples of indirect causes are acid
rain and disposal of radioactive
substances.
The main reasons of soil pollution
are briefly described below: Fig. 5.11 Soil pollution causes
(i) Faulty Agricultural Practices
(a) Unskilled Irrigation Waterlogging may occur when the drainage system of the
agricultural field is not maintained scientifically. Waterlogging closes the passage of
air to the soil, stops the growth of soil organisms and makes the soil barren.
(b) Shifting Cultivation In it, the forest is burnt to use the land for cultivation.
However, this practice exposes the soil for soil erosion.
(c) Injudicious Use of Chemical Fertilisers Use of inorganic fertilisers increases
the nutrient contamination. The microbes of the soil reduce the nitrogen to nitrite
ions which enter the animal body through food or water. It is directly absorbed in the
bloodstream and oxidises the oxyhaemoglobin (the O2 carrier) to methemoglobin.
The latter cannot carry oxygen any more; so ultimately the animal dies.
(d) Pesticides Pesticides are chemicals which are used by farmers to protect their
crops. Large amounts of pesticide in the soil interfere with the soil’s metabolic process.
Pesticides kill many nontargeted beneficial soil organisms such as earthworms. Thus,
the soil becomes infertile.
Organo-chlorides (like Dichloro Diphenyl Trichloroethane, DDT) are second
generation pesticides. They are nonbiodegradable substances. They accumulate and
magnify in the food chain and interfere with the calcium metabolism of birds. As a
consequence, birds lay fragile, thin-shelled eggs.
High concentration of pesticides get accumulated in fatty tissues of prey
organisms. When predators eat these prey organisms, they also get killed.
Thus, pesticides lead to poisoning of the ecosystem.
(ii) Mining For mining, trees are cut down. Loss of greenary results in land
degradation, drought and desertification. This is illustrated in Fig. 5.12.
(iii) Solid Wastes from Homes and Industries Chemical, petroleum, and
metal-related industries, dry cleaners and gas stations produce hazardous waste such
as oils, battery metals and organic solvents. These hazardous wastes contaminate soil
and water resources.
Fig. 5.12 Land-degradation cycle due to mining and related activities
(iv) Acid Rain It converts neutral soil to an acidic one.
5.6.2 Effects of Soil Pollution

The harmful effects of soil pollution are briefly described below:
(i) Fluorosis occurs as a result of consumption of fluoride containing maize
and jawar crops. The fluoride is absorbed by the crops from the fluoride-
contaminated soil.
(ii) Emission of toxic gases (from dumped solid wastes on land) are detrimental
to health. The unpleasant smell and spread of insects cause inconvenience to
people.
(iii) Poisoning of the ecosystem takes place by soil pollution.
(iv) Contamination of underground and surface drinking water takes place by
soil pollution.
(v) Reduction in the fertility of soil takes place by soil pollution.
Fig. 5.13 Harmful effects of soil pollution
5.6.3 Control of Soil Pollution

The land pollution can be controlled by the following methods:
(i) Polluted soil can be treated by bioremediation. It uses microorganisms (yeast,
fungi or bacteria) to break down, or degrade, hazardous substances into less
toxic or nontoxic substances (such as CO2 and H2O). Proper treatment of

liquid wastes from industries and mines must be done.
(ii) The principles of three Rs, namely, Recycle, Reuse and Reduce, help in
minimising the generation of solid waste. For example, use of biofertilisers
and natural pesticides help in minimising usage of chemical fertilisers and
pesticides.
(iii) Proper disposal methods must be employed. For example, composting of
biodegradable solids and incineration of nonbiodegradable solids should be
done.
(iv) Planned afforestation helps in preventing soil erosion.
(v) Formulation and effective implementation of stringent pollution-control
legislation also helps in controlling soil pollution.
(vi) Faulty sanitation practices must be improved.
Fig. 5.14 Control of land pollution
Case Studies
(i) Soil Pollution in Patancheru Industrial Area, Hyderabad, Andhra
Pradesh, India
The Patancheru industrial development area is in Hyderabad, which is the fifth
largest city in India. In this area, soil environmental hazards are increasing at
an alarming rate because of rapid industrialisaiton and indiscriminate disposal
of waste materials without adequate knowledge of toxic pollutants and their
control. Studies have shown that the soil from resudential areas is moderately
contaminated with Cr, Ni and Pb. The area needs bioaccumulators to remove
toxic metals.
[Res. J. Environ. Earth Sci:, 3(3): 214-220, 2011; http: //mawellsci.com/
print/rjees/v3-214-220.pdf]
(ii) Heavy Metal Contamination in Different Vegetables
[http: //scialert.net/fulltext/? doi=rjet.2011.162.179 and org = 10]
Heavy metals such as cadmium, copper, lead, chromium, and mercury are very
harmful because of their long biological half-lives, nonbiodegradable nature and
their potential to accumulate in different body parts. Plants take up heavy metals
by absorbing them as deposits on the parts of the plants exposed to the air, from
polluted environment as well as from contaminated soil.
Recent findings of heavy metal contamination in vegetables:

(a) Waste water contains a substantial amount of toxic heavy metals.
(b) Waste-water irrigation results in the accumulation of heavy metals in soil
and vegetables.
(c) Excessive accumulation of heavy metals adversely affects the food quality
and safety.
(d) Unwashed vegetable contain high concentrations of toxic elements result-
ing from the accumulation of air-borne heavy metals.
(e) Heavy metals get concentrated/accumulated in edible portions of leafy or
root crops than storage organs or fruits.
(f) Accumulation of heavy metals in fruits is low (unlike vegetables). This is
because a large proportion of heavy metals absorbed by trees are stored in
other organs like leaves.
(g) Consumers of heavy-metal-contaminated vegetables are at health risks.
(h) Consumption of vegetables grown on urban waste dumpsites is dangerous
to human health.
(i) The transportation and marketing of vegetables in contaminated
environments elevates the levels of heavy metals in vegetables through
surface deposition.
(j) To reduce health risks, vegetables should be washed properly before
consumption. This is because on washing, a significant amount of aerial
contamination from the vegetable surfaces is removed.
5.7 MARINE POLLUTION

When the salt content of a water body is equal to or more than 35 parts per thousand
(ppt), then it is known as a marine water body.
Examples of Marine Water Bodies: Seas, oceans, brackish water, salt marshes, etc.
Marine pollution is defined as the direct or indirect discharge of matter or energy
by humans into marine water bodies that is harmful to living organisms, hazardous to
human health, hinders marine activity, adversely affects sea-water quality and reduces
its amenities.
Thus, marine pollution is harmful and is caused by human activities. Damages
or disturbances caused by earthquakes, volcanic eruptions, tsunamis, etc., are not
considered marine pollution.
Oceans are ultimate sink for most of the waste we produce. This is because any
waste material which is released into the river system (and many sewage systems
around the world) will exit into the ocean. Marine pollution is also known as ocean
pollution.
(i) Land Sources of Marine Pollution Radioactive substances, toxic chemicals,
solid waste, thermal pollution, sewage, nutrients, pathogens, etc., are some of the
land-based pollutants which cause maximum loss to coastal and marine ecosystems.
(ii) Offshore Source of Marine Pollution They include release of ‘produced

water’ from the oil-bearing strata with the gas and the oil at the time of production.
‘The produced water’ together with waste-drilling chemicals and mud is discharged
into the ocean.
From offshore operations, ‘oil spills’ are caused by equipment malfunctioning,
pipeline breakage, etc.
From submarine oil deposits, ‘natural seepage of petroleum hydrocarbons’ also
contributes to marine pollution.
5.7.1 Sources and Effects of Marine Pollution

The major sources of marine pollution and their effects are briefly described below:
(A) Sewage
All over the world, untreated (or undertreated) sewage is discharged into the oceans.
It contributes pathogens and nutrients to oceans.
Effects Nutrients cause algae blooms (eutrophication) in coastal waters.
Decomposing of algae depletes the water of oxygen, killing other marine animals.
Algal bloom releases toxins that can kill fish and poison people.
Eutrophication has created enormous dead zones in several parts of the world,
including the Baltic sea and the Gulf of Mexico.
Pathogens contaminate coastal swimming areas and seafood, spreading typhoid,
cholera, etc.
(B) Toxic Chemicals
Chemicals like DDT, heavy metals, etc., which have toxic effects are known as toxic
chemicals. They come from industrial discharge, waste-water discharge from cities;
seepage from landfills and pesticides from home use, farms, forests, etc.
Effects Toxic chemicals cause disease in coastal marine life especially near
industries or major cities. They contaminate seafood. Disease and reproductive
failure is caused by fat-soluble toxins that biomagnify in predators. By eating
contaminated seafood and animal fats, cancer, damage to the immune system,
behavioural problems, and reduced fertility etc., are caused in humans.
(C) Thermal Pollution
Discharge of cooling water is at about 10°C above the temperature of the receiving
water from power stations.
Effects Heat can kill corals and other temperature-sensitive sedentary species. It
can displace other marine life. Increase in water temperature causes a lowering of
dissolved oxygen levels.
(D) Oil
Oil pollution in marine water is caused by maritime accidents, wars, offshore
oil drilling, oil-tanker accidents, conventional shipping, tank cleaning at sea, oil
exploration, etc. It has been estimated that about 80 to 200 litres of oil is spilled in
the ocean per second.
Effects A drop of petroleum oil spread over marine water surface becomes more
dark and viscous due to slow evaporation of lighter volatile fractions. The oil is
polymerised to highly viscous tar balls by sunlight and oxygen, causing litter. Besides
this, an oil film floating on water inhibits sunlight from entering the sea, thereby
prohibiting photosynthesis of aquatic plants and simultaneous oxygen production.
Fig. 5.15 Sources of marine pollution (Safe-environment.wordpress.com//)
Fig. 5.16 Marine pollutants
The fur of marine mammals and feathers of diving birds get soaked with
oil, displacing the air present there, interfering with their buoyancy and natural
insulation required for maintenance of body temperature. Once these mammals
or birds are soaked, they either get drowned or die due to loss of body heat. From
oils, hydrocarbons also enter the human body through the food chain and cause
biomagnification.
(E) Radioactive Substances
The oceans are a sink for radioactive waste from the production of nuclear weapons,
electricity, testing of nuclear weapons and nuclear accidents.
Effects Radioactive substances get concentrated in predators and shellfish, which
are eaten by humans.
Radioactive substances cause disease in marine life, and are a great threat to
civilisation. It has been predicted that the survival ability of the human species is
reduced because several generations are exposed to radiation.
(F) Solid Wastes
Much of the solid wastes are composed of plastics like polythene containers, plastic
sheets, nylon ropes and nylon nets with variable sizes and shapes.
Effects Plastics are nonbiodegradable. They remain in the oceans for 200 to
400 years and come back to the shore and continue littering beaches and coasts.
Plastics eaten by seabirds causes reduction in appetite, sensation and development of

stomach and intestinal ulcers. Fish, turtles, seals and seabirds can become entangled
in discarded plastic fishing nets which trap and slowly strangle them. Plastic waste is
often mistaken for food by marine animals. Plastic bags have been found blocking
the breathing passages and stomachs of many marine species including turtles,
dolphins, whales, etc.
5.7.2 Control of Marine Pollution

Marine pollution can be controlled through the following measures:
(i) Countries should improve existing sewage-disposal facilities.
(ii) Industries should adopt zero waste technologies. They should discharge
waste after treatment with best available technology. It will help in the
minimisation of release of toxic or damaging substances.
(iii) Agricultural and aqua-cultural practices should integrate recycling, waste
treatment and proper handling for minimum discharge of pollutants.
(iv) Bioremedial controls should be used in which bacteria and other
microorganisms are employed to alter and break the complex toxic chemical
into harmless products and CO2.
(v) Governments should develop and enforce legislation relevant to the
management of residential and tourism development in the coastal zone.
(vi) Legal permit should be issued or denied based on detailed Environmental
Impact Assessment (EIA) or Environmental Impact Statement (EIS).
(vii) Individual humans should ensure that their houses have sewage disposal
systems, such as septic tanks.
Fig. 5.17 Control of marine pollution
Case Studies
(i) Effects of Thermal Power Plant on Marine Ecological Habitat
Marine backwaters including estuaries and tidal creeks face tremendous stress
from disposal of industrial, agricultural and domestic wastes. These water
bodies possess self-purification capacity through diurnal tidal cycle and constant
ecological integrations.
Major ecological concerns due to thermal discharges from power plants are
sublethal damage to biological communities, adverse impact on regeneration
process in native biota, alternation in primary and secondary production, etc.
Periodic observations are necessary to estimate the exact response of biotic

communities to changing temperature, pH, salinity, enabling retaining a better
quantity of creek and associated mangrove habitats.
[Jagtap et al; Journal of Environmental Biology, March 2011, www.job.co.in]
(ii) Ocean Pollution
There are eighty-seven cities and towns located within 50 km of India’s 8,000
km coastline. In these coastal areas, nearly 250 million people live and dump
5.5 billion litres of waste water into the sea every day. Less than 0.5 billion litres
of waste water is treated. Municipal waste water constitutes the single largest
source of marine pollution. The three states of Maharashtra (45%), West Bengal
(26%) and Tamil Nadu (9%) account for the bulk of waste water flushed into
our coastal seas.
Fifteen locations that degrade our coastal ecosystems with untreated effuents,
contaminated with metals, chemicals and raw sewage are Hooghly, Paradip,
Visakhapatnam, Kakinada, Bhimavaram, Ennore, Pondicherry, Cuddalore,
Tuticorin, Kochi, Mangalore, Goa, Thane creek, Mahim, Versova and Bassein
(Mumbai), Hazira.
Common effluent-treatment plants for small-scale industries, monitoring,
local-scale solutions, costs, benefit-sharing and empowerement are possible
solutions for ocean pollution.
[RahulGoswami;http://infochangeindia.org/agenda/coastal-communities/
ocean-pollution.html]
5.8 NOISE POLLUTION

Vibrations transmitted through an elastic medium (air, water or solids), with
frequencies in the approximate range of 20 to 20,000 hertz, capable of being
detected by ears is known as sound.
Noise is a sound that is undesired, unexpected, unpleasant or loud. It is undesired
in that it interferes with sleep, rest, recreation, work or communication. The word
noise comes from the Latin word nausea meaning sea sickness.
Noise pollution is defined as environmental noise or an unwanted sound that is
annoying, distracting, or physically harmful. Harms include hearing loss, stress,
sleeplessness, etc. Noise pollution is also known as sound pollution.
There are about 25,000 hair cells in our ear which create waves in our ear,
corresponding to sound in the environment, as a response to different levels of
frequencies. With increasing intensity/pitch/loudness of sound, the cells get
destroyed decreasing our ability to hear high-frequency sounds.
Decibel (dB) is used as a measure of sound intensity level or sound pressure level.
It is named after Alexander Graham Bell, the inventor of the telephone.
È Intensity measured ˘
Intensity level (dB) = 10 log10 Í ˙
Î Reference intensity ˚
ÊI ˆ
fi dB = 10 log10 Á m ˜ (5.1)
Ë Io ¯
As intensity varies with the square of pressure, intensity level can also be replaced
as Sound Pressure Level (SPL).
Thus,
2
Ê Pressure measured ˆ
SPL (dB) = 10 log10 Á
Ë Reference pressure ˜¯
Ê Pressure measured ˆ
fi SPL (dB) = 20 log10 Á
Ë Reference pressure ˜¯
ÊP ˆ
fi SPL (dB) = 20 log10 Á m ˜ (5.2)
Ë Po ¯
Note that decibels is a logarithmic scale. A change from source (A) of sound
(intensity measured = 10 watts/m2) with another source (B) of sound (with intensity
measured = 1000 watts/m2) causes a change of 20 dB of noise:
dBB – dBA = 10 ÈÎ( log I m - log I o ) - (log I m - log I o)˘˚

B A
= 10[(log(1000) - log I o - log(10) + log I o ]

È Ê 1000 ˆ ˘
= 10 Ílog ÁË ˜ = 10 ¥ 2 = 20
Î 10 ¯ ˙˚
Thus, a change of 20 dB represents a 100-fold increase in loudness.
Apart from loudness, the frequency or pitch of the sound also determines whether
it is harmful or not. A modified scale called decibel–A [dB(A)] takes pitch into
account. Average noise levels of some sources are summarised in Fig. 5.18.
For humans, normal level of tolerance is 80 dBA. Sound level above or below this
is considered as noise pollution.
Most of the electronic vehicles and motors emit sound above 80 dBA level.
Amplified rock music is 120 dBA.
Fig. 5.18 Harmful levels of noise

Legislation In 2000, the Government of India notified Noise Regulation Rules
under the Environment (Protection) Act of 1986. Sectorwise limits to noise levels
are summarised on next page:
Sector Industrial Commercial Residential

Limit 75 dB 65 dB 55 dB
Further, use of public address systems after 10 p.m. and before 6 a.m. is not
permitted.
Rules also establish zones of silence Table 5.3 Average noise levels of some
within a radius of 100 m of schools, noise sources
courts, hospitals, etc. Source Noise level in dB(A)
Threshold of audibility/ 0
5.8.1 Sources of Noise hearing
Source is the equipment or process Conversation–quiet 20–30
directly responsible for sound genera-
Conversation–Face to face 60
tion.
The major sources of noise are sum- Classroom teaching 55–60
marised below: Home appliances 65–75
Road Traffic–Medium 70–80
(i) Transportation Sources Rail-
ways, road traffic and air traffic. Road Traffic–Heavy 80–90
Inside cinema hall 85–95
(ii) Industrial Sources Noise is
Horns of vehicles 90–105
generated in mostly all industrial activ-
ities such as power generation, process- Rail engine at 15 m 97–105
ing, product fabrication and product Loudspeakers 100–120
assembly. Threshold of pain 130
Jet engine at 25 m 140
(iii) Public Address System Sourc-
es Use of loudspeaker at any occasion Diwali crackers 125–160
like marriages, functions, festivals, etc. Bomb explosion 190
(iv) Agricultural Machine Sources Use of tractors, tubewells, farm machines

for agriculture.
(v) Defence Equipment Sources Shooting practices, wars, bomb explosion, etc.
(vi) Household Sources Mixer-grinder, lawn mowers, food blenders, vacuum
cleaners, etc.
(vii) Other Sources Rock concerts, barking dogs, construction equipments, etc.
5.8.2 Effects of Noise Pollution

Noise affects human health in the following ways:
(i) Physical Effects Damage to ear drum, temporary impairment of hearing,
permanent deafness.
(ii) Physiological Effects Muscular strain, headache, eye strain, decreased
colour perception, nervous breakdown, pain in heart, etc.
(iii) Psychological Effects Emotional disturbance, depression, fatigue, frusta-
tion, irritation, reduced efficiency, etc.
5.8.3 Control of Noise Pollution

Noise pollution can be controlled by reducing noise at the source, interrupting the
path of noise and/or protecting the receiver.
(i) Noise Control at the Source It is most effective to eliminate noise at the
source.
Examples
(a) Reduction of noise generated by mechanical vibration of a machine by
damping or isolation of the vibration by applying a damping material
(rubber) to the vibrating components.
(b) Reduction of impact force by optimising the impact distance and covering
either or both impact surfaces by rubber.
(c) Modification of manufacturing design like enclosing the engine parts within
proper noise-insulating material.
Fig. 5.19 Noise control
(ii) Noise Control at Path When the source cannot be made quiet, noise can be
controlled by modifying the path.
Examples
(a) Attenuation of noise by moving noise source away from sensitive area
(b) Suppression of noise from automobiles using silencers
(c) Reduction of noise around residential areas by planting trees in the form of
green belt
(d) Reduction of transmission of noise using acoustic screens and barriers
(e) Enclosing noisy machines in isolated buildings
(iii) Noise Control at Receiver If source and/or path control do not work,
control at the receiver should be explored.
(a) Use of Hearing Protection Devices (HPD) like ear plugs, ear muffs, etc.
They reduce the level of noise (by 10 dB to 55 dB) entering the outer and
middle ears before it reaches the inner ear.
(b) Enclose receiver.
(c) Relocate receiver.
Fig. 5.20 Comparison of noise-reduction methods applied to a machine
Case Studies
(i) Solution of Noise Pollution: Sustainable Urban Transport
The transportation sector is growing fast in India due to rapid urbanisation.
It has resulted in overcrowded roads and traffic noise pollution. The major
pollutants are gasoline-driven vehicles. In most congested parts of Delhi, the city
experiences noise pollution beyond the accepted prescribed limit. The city also
faces problems due to excessive air pollution of more than 2000 tonnes per year.
The traffic problems are heterogeneous movement of traffic, inadequate road
capacity, poor mass-transportation facilities and high intensity of private vehicles
on the road.
The transport sector is also responsible for the greenhouse effect. It is one of the
biggest threats to our society and sustainability. Negative impacts of greenhouse
effects include the melting of most of the polar ice and rise in sea level resulting
in population displacement, destruction of low-lying urban infrastructure,
inundation of arable land, contamination of freshwater and spread of diseases

such as malaria, dengue, etc.
Carbon dioxide, methane and nitrous oxide gases are generated by vehicular
traffic. These gases and chlorofluorocarbons (CFCs) are the primary greenhouse
gases contributing to global warming.
Owing to environment-friendly concepts, energy requirements, possible
consequences of energy scarcity of oil-based transport and damages caused by it
on the environment, there is an urgent need of sustainable transport.
Sustainable transport refers to any means of transport with less impact on the
environment and which promotes healthy lifestyles. It includes walking, cycling,
green vehicles and transport systems that are fuel efficient.
For metros like Kolkata we need sustainable transport. This is because, around
13 million inhabitants of Kolkata suffer from respiratory problems such as lung
cancer and asthma. These problems are caused by pollution from the chaotic
transport system of the city.
[Sarkar et al., current science, Vol.100, No. 9, 10 May 2011
http: //www.ias.ac.in/currsci/10 may 2011/1349-pdf]
(ii) Noise and Quality of Life
The noise levels in the work zone of a thermal power plant are greater than
the prescribed standards. The thermal power plant cannot achieve its targeted
demand because the quality of life of all the workers is not maintained.
The noise levels of a steel plant even affect far-field locations and thus disturb
the quality of life of the rural settings.
An increase in the ambient noise results in deteriorated indoor noise levels and
speech intelligibility in classrooms.
In different mining complexes, the mechanised mining operations create
excessive noise both in the work areas as well as in the surrounding areas. The
noise generation greatly disturbs the quality of life of the inhabitants residing
near the mining areas.
Workshops of many areas have maximum noise pollution. To avoid occuptional
hearing loss, older workers of workshops should be regularly changed to work in
less-influenced areas. Ear protective less-influenced devices should be worn by all
workshop workers.
[Kerketta et al., Internationsl Journal of Environmental sciences, Vol.1/ No.
7, 2011 (http: //:publishing.co.in/jes vol 1 no 1 2010/E1JES 2124.pdf)]
5.9 THERMAL POLLUTION

Thermal pollution may be defined as the degradation of water quality by any process that
changes ambient water temperature.
5.9.1 Causes of Thermal Pollution

Causes (or sources) of thermal pollution are briefly described below:
(i) Coal-fired Power Plants River water is used for cooling the condenser rods
of coal-fired thermal power plants. When water used as a coolant is returned to the
river, its temperature is high, which lowers down the dissolved oxygen of water and
affects ecosystem composition.
(ii) Nuclear Power Plants Large amount of heat along with toxic radionuclides
are discharged into nearby water streams by nuclear power plants. Radiation
leakages are also responsible for increasing the temperature of water bodies. Nuclear
experiments and nuclear explosions are also responsible for thermal pollution.
(iii) Domestic Sewage Normally, the municipal water sewage has a higher
temperature than normal water. When domestic sewage is discharged into lakes,
rivers, etc., it causes thermal pollution.
(iv) Industrial Effluents Textile, sugar, paper, pulp and various other industrial
effluents when discharged into lakes, rivers, etc., cause thermal pollution.
(v) Deforestation When shade-providing trees are cut down, water temperature
rises.
5.9.2 Effects of Thermal Pollution

The harmful effects of thermal pollution are described below:
(i) Reduction in DO Elevated temperature typically decreases the level of
dissolved oxygen in water. This can harm aquatic animals.
(ii) Change in Quality With rise in temperature, the density, viscosity and
solubility of gases in water decreases.
(iii) Damage to Biological Activity Above 37°C, biological activity of enzymes
of aquatic flora and fauna gets severely damaged.
(iv) Interference with Reproduction Capability Temperatures higher than
9 to 10°C interfere with reproduction capabilities of certain fishes.
(v) Increase in Metabolic Activity At increased temperatures, metabolic
activities such as oxygen uptake, food intake and mobility of fishes are increased.
(vi) Shortening of Longevity The lifespan shortens due to increased metabolic
activity. For example, a crustacean lives for 108 days at 7.8°C. But if the temperature
of water is increased to 21°C, it can live for only 29 days.
(vii) Increased Vulnerability to Diseases With temperature rise, the
vulnerability or susceptibility to diseases also increases.
(viii) Increased Mortality Rate At higher temperatures, the mortality rate of
fish and all other aquatic organisms increases.
(ix) Decreased Biodiversity Adjacent to thermal discharge, some fish species
will avoid stream segments or coastal areas because they may not be used to the
warmer temperatures. However, the more adapted organisms might move in. An
increased metabolic rate may result in fewer resources which lead to compromise in
the new and old food chains. Biodiversity can decrease as a result.
(x) Malnutrition High temperatures can lead to the denaturing of life-supporting
enzymes. It means, within the quaternary structure of the enzymes, hydrogen bonds
and disulphide bonds break down. In aquatic organisms, these reduced activities of
enzymes can cause problems such as the inability to break down lipids, leading to
malnutrition.
(xi) Ecological Effects of Cold Water Elimination of native fish species,
and drastic alteration of macroinvertebrate fauna has been observed by releases of
unnaturally cold water from reservoirs like dams.
5.9.3 Control Measures of Thermal Pollution

Heated water from power plants, petroleum refineries, pulp and paper mills, steel
mills and chemical plants can be cooled down for controlling thermal pollution by
using cooling ponds, cooling towers, etc.
(i) Cooling ponds are man-made bodies of water which help in reducing the
temperature of water by evaporation, convection and radiation (Fig. 5.21).
(ii) Cooling towers transfer waste heat to the atmosphere through evaporation
and/or heat transfer (Fig. 5.22).
(iii) Cogeneration is a process for recycling waste heat for domestic and/or
industrial heating purposes.
(iv) Stormwater management facilities absorb urban run-off or direct it
into groundwater, such as bioretention systems. Otherwise, urban run-off
can have significant thermal impact during summers on small streams, as
stormwater passes over hot parking lots, roads and sidewalks.
Fig. 5.21 Power plant with recirculating cooling pond

Fig. 5.22 Counterflow type cooling tower
(v) Afforestation By planting trees along streams and shorelines, thermal

pollution can be controlled. If these trees and tall plants are not there for
providing shade, the water warms by as much as 10°C. Even removal of
vegetation far away from a lake can speed up the erosion of soil into water,
making it muddy. Muddy water absorbs more energy from the sun than
clear water does, resulting in further heating, Afforestation controls erosion,
keeps water clearer and thus, cooler.
Case Study
Thermal Pollution
Thermal pollution is the act of altering the temperature of a river, lake, ocean or
any other natural water body. Environmental consequences of thermal pollution
include decrease in biodiversity, creation of an environment hospitable to alien
aquatic species, etc. Waste heat discharged to natural waters typically reduces the
dissolved oxygen content. The resulting higher water temperatures specifically
raises the metabolic rate of aquatic organisms.
Higher enzyme activity occurs causing plants and animals to take in greater
amounts of nutrients and CO2/O2. These metabolic changes can alter the balance
of species composition, species migration, etc.
Use of cooling ponds, cooling towers, productive use of the heated water for a
secondary industrial process or space heating are some of the methods of reducing
impacts of warm-water thermal discharges.
The Turkey Point nuclear power station (South Florida) removes water from
Biscayne Bay and then passes it through condensers. The output water with an
increased temperature of up to 15°C above ambient is then pumped back into

the receiving water. The cooling water is discharged into a shallow soft-bottomed
area. The water temperature around the outfall pipe at Turkey Point is 30–35°C.
It is estimated that about 9.3 hectares of turtle grass has been destroyed around
this outfall because of a temperature increase of 5°C.
Some of the impacts of thermal pollution on the local marine community
surrounding the outfall pipes of coastal power stations are
(i) Death of marine animals like sponges, molluscus, crustaceans (e.g. crabs)
(ii) Replacement of turtle grass by blue-green algae
(iii) Change in community structure around the outfall pipe
[http://www.chengapedia.de/vsegine/vlu/vsc/en/ch/16/uc/vlus/thermal
pollution/case studies/thermal/thermal turkey.vscml.html]
5.10 HAZARDOUS WASTES

Hazardous wastes can be defined as useless, unwanted and discarded materials that
may pose a threat to human, plant or animal life.
OR
“A waste or combination of wastes which because of the concentration, quantity or
physical, chemical or infectious characteristics may cause, or significantly contribute
to increase in mortality or an increase in serious irreversible, or incapacitating
reversible illness, or pose a substantial present or potential hazard to human health
or the environment when stored, transported, disposed off, improperly treated or
improperly managed.”
OR
“Waste that possessess reactivity or ignitability or corrosivity or toxicity.”
(i) Reactive waste is a waste which is not stable at normal conditions. It can
cause explosive reactions or liberate toxic fumes, gases or vapours. It can
react violently with water.
Examples Dry picric acid, sodium metal, etc.
(ii) Ignitable waste is a waste which is easily ignited and burns vigorously at or
below 60°C.
Examples Paint thinner, solvents (ethers, acetone, toluene)
(iii) Corrosive waste is generally a waste in liquid physical form that can corrode
metal and which has pH less then 2 or greater than 12.5.
Examples Battery acid, drain openers, H2 SO4, HCl, NaOH, lime, etc.
(iv) Toxic waste is a waste which releases toxic materials on leaching in excess of
the permissible concentration. These toxic substances are harmful or fatal
when ingested or absorbed.
Examples Nickel–cadmium batteries, lead batteries, mercury batteries, rat
poison, antifreeze, etc.
A waste is considered hazardous (as regards human toxicity) if
(i) It has an oral LD 50 toxicity ≥ 50 mg/kg
(ii) It has an inhalation LC 50 toxicity = 2 mg/kg
LD 50 is the lethal dose of the toxic waste at which 50% of experimental animals
die as a result of dermal penetration or oral ingestion.
LC 50 is the lethal ambient concentration of the toxic material in mg/L of air
causing 50% mortality to test rats during 4 hours of inhalation.
Toxicity can be acute or chronic. The adverse effects of a substance which result
either from a single exposure or from multiple exposures within a day are described
as acute toxicity.
The adverse health effects from repeated exposures, often at lower level, to a
substance over a long time period (months or years) are described as chronic
toxicity.
5.10.1 Environmental Problems and Health Risks Associated

with Hazardous Wastes
For a hazardous waste to pose a risk, a material/plant/animal/person must be exposed
to it in a way that can cause harm.
Exposure may occur through air, drinking water, soil or food. When the waste
spilled onto the soil includes volatile organic chemicals, these can evaporate. Direct
inhalation by on-site workers or humans who live extremely near the site can cause
harm. Evaporated volatile organic compounds could settle onto corn plants and
trees and other vegetation. Animals may eat the contaminated vegetation or grain.
Later, humans may eat the contaminated vegetation, grain, or meat. Soil is a direct
exposure source for plants and animals on site. Spilled waste could percolate into
groundwater or run off into surface water. The most likely exposure route for those
living near such sites is the groundwater that is used for drinking.
(i) Arsenic, cyanide, pesticides, etc., are toxic substances which can adversely
affect the health of living organisms exposed to them.
(ii) Strong acids and strong alkalis are corrosive substances which can cause severe
injury at the point of contact, i.e. the skin, eyes, lungs, or mouth.
(iii) Petroleum distillates, many organic solvents, ethyl ether are ignitable or flam-
mable substances which can easily catch on fire. They are thus fire hazards.
(iv) If ammonia and chlorine bleach are mixed together, they will react to form
toxic fumes, which can adversely affect humans. If ethers are left sitting in
their containers for years, they can form explosive peroxides.
(v) Battery acids can corrode metal.
(vi) Strontium-90 and Iodine-137 are slow decaying and produce hazardous
effect on human life.
(vii) Radioactive wastes generate radiations which can have somatic or genetic
effects on living cells.
The somatic effects are caused on exposed individuals. The cell damage caused
may result in cancer or leukemia. The genetic effects are transmitted from the
exposed individuals to their descendants.
The radiation-induced changes in the genes may result in gene mutations,
chromosome aberrations and changes in the number of chromosomes. Such
changes can result in mild or lethal abnormalities in the offsprings.
(viii) As, Pb, Cd and Hg are inorganic toxic chemicals, they act as biological poisons
even at parts per billion (ppb) levels.
When coal, leaded gasoline and other fossil fuels are burnt, these toxic
metals enter the atmosphere. Low pH caused by acid rain or the generation
of CO2 increases the transportability and hence availability of these metals
by rendering them more soluble. These chemicals also leach out from mines
and landfills. Then they contaminate land. In soil and sediments, these toxic
elements accumulate in organic matter and are taken up by growing plants,
thus entering the food chain. They accumulate in organs and tissues to toxic
levels in the body since they are poorly excreted by humans.
(ix) Pesticides (DDT), Polychlorinated Biphenyls (PCBs) are hazardous organic
chemicals. They slowly degrade in the environmental. They are fat soluble;
so they accumulate in the food chain. They cause immediate toxicity as well
as long-term effects such as carcinogenicity and mutagenicity.
(x) In the course of curing health problems, the health-care sector produces
huge amounts of biomedical waste which is hazardous to all those who come
in contact with it,
Bacteria (tuberculosis) and viruses (HIV, Hepatitis B and Hepatitis C) can
be transmitted by contact with an infected patient or contaminated body
secretion/fluid.
Progressive increase in hospital infection rate, and increasing resistance to
wide variety of antibiotics are the pointers to the way in which poor hospital
waste management can contribute to ill health. There is also risk of pollution
of water, air and soil.
5.10.2 Different Methods for Treatment of Hazardous Waste

There are two reasons for treating hazardous waste: one is to reduce the volume of
the waste; the other is to reduce its toxicity.
Hazardous waste can be treated by various methods (Fig. 5.23). These and many
other are briefly described below:
(A) Physical Treatment Methods
(i) A liquid is separated from a solid using a membrane in filtration. The liquid
goes through membrane pores. The solid particles are retained on the surface
of the membrane, and its volume is much reduced. If enough hazardous
material is filtered out, the liquid coming through the membrane (the
filtrate) may no longer be hazardous.
(ii) To separate a mixture of liquids, distillation is sometimes done. The
mixture of liquids is heated. Lower temperatures drive off the more volatile
substance, leaving behind those with higher boiling points. Depending on
the chemicals, the waste remaining may or may not be hazardous. Volumes
of some components can be reduced too.
(iii) To remove hazardous material from a solution, aeration can be done.
Contaminated waste solution is sprayed downward through a packing
material in a tower, through which air is blown upward carrying away the
Fig. 5.23 Various methods used for the treatment of toxic industrial waste water
Volatile Organic Compounds (VOCs) such as benzene, toluene, CHCl3,

CCl4, etc.
(iv) After the removal of volatile substances, waste water is subjected to adsorption.
In this process, hazardous chemicals are adsorbed onto Granular Activated
Carbon (GAC) adsorbent. The adsorption process uses a series of large
vessels partially filled with GAC. Contaminated water enters the top of each
vessel, trickles down the GAC and is released at the bottom. GAC has large
surface area of about 1000 m2/g. It helps in removal of dissolved hazardous
substance that cannot be removed by sedimentation.
(v) Reverse osmosis, electrodialysis and ion-exchange processes are other physical
methods for treatment of hazardous waste.
(B) Chemical Treatment Methods
(i) Ion-exchange Process Anion exchangers are used for the removal of anionic
nickel cyanide complex and chromate ions from hazardous waste solution.
2 Res+ OH– + [Ni(CN)4]2– Æ (Res+)2[Ni(CN)4]2– + 2 OH–
2 Res+ OH– + CrO2– + 2–
4 Æ (Res )2[(CrO 4] + 2 OH
–
Ion-exchange resins have also been used for the removal of radionuclides from
radioactive wastes.
(ii) Hydrolysis Treatment It is given to those hazardous waste constituents
(like halides, carbide, hydride, alkoxide and active metal) which are very reactive
with water.
SiCl4 + 2 H2O Æ SiO2 + 4 HCl
CaC2 + 2 H2O Æ Ca(OH)2 + C2H2
NaAlH4 + 4 H2O Æ 4 H2 + NaOH + Al(OH)3
NaOC2H5 + H2O Æ NaOH + C2H5OH

Ca + 2 H2O Æ Ca(OH)2 + H2
(iii) Chemical Precipitation Technique In this technique, the pH is properly
adjusted for decreasing the solubility of toxic metals. A precipitate is subsequently
formed that is then removed by settling and filtration.
(a) Chromium is precipitated as hydroxide using lime for precipitation.
Cr3+ + 3 OH– Æ Cr(OH3)Ø
(b) Sodium carbonate (Na2CO3) is used to precipitate metals as hydroxides
(Fe(OH)3 x H2O), carbonates (CdCO3), basic carbonate salts (2PbCO3,
Pb(OH)2).
(c) Sodium borohydride (NaBH4) is a reducing agent. It is used to precipitate
metal ions from solution in the elemental from.
4 Cu2+ + NaBH4 + 2H2O Æ 4 Cu + NaBO2 + 8H+
(d) Metals can be precipitated as sulphides when they are present in very low
concentrations. Metal sulphides have lower solubilities than metal hydroxides
and hence can be precipitated out. Ferrous sulphide is used as a safe source
of sulphide ions to produce sulphide precipitates with other metals that are
less soluble than ferrous sulphide.
(e) Lime is used for precipitation of metal ions as metal hydroxides.
M 2+ + Ca(OH)2 Æ Ca2+ + M(OH)2 Ø
(iv) Neutralisation Process Hazardous wastes are termed corrosive when their
solution pH is less than 2 or more than 12.5. Neutralisation process converts these
materials to less hazardous ones by changing their pH.
(a) Lime is the least expensive. It is used for neutralisation of acidic wastes.
(b) Relatively inexpensive sulphuric acid is used for neutralisation of alkaline
wastes.
(c) Nontoxic and biodegradable acetic acid is preferable for some applications
where alkaline wastes need neutralisation.
(d) Alkaline wastes can also be neutralised by bubbling gaseous carbon dioxide.
CO2 + H2O Æ H2CO3
H2CO3 Æ 2H+ + CO32–
H+ + OH– Æ H2O
The advantages of CO2 is that it is
often easily available in the exhaust gas
from any combustion process at the
treatment site.
In the same vessel, simultaneous
neutralisation of waste acid and waste Fig. 5.24 Simultaneous neutralisation
base can also be done (Fig. 5.24). of acid and base
(v) Oxidation–Reduction Process By redox reactions, toxic substances are
converted to those oxidation states which are less toxic.
(a) Hexavalent chromium (Cr6+) is reduced to trivalent chromium (Cr3+) by

using sulpher dioxide as a reducing agent.
SO2
Cr6+ Cr3+
Carcinogen Less toxic
3 SO2 + 3H2O Æ 3H2SO3
2CrO3 + 3H2SO3 Æ Cr2(SO4)3 + 3H2O
(b) From metal finishing industry, toxic cyanide waste is oxidised using chlorine
in alkali solution. First, the less toxic cyanate is formed. Finally, CO2 and N2
gases are evolved.
NaCN + Cl2 + 2 NaOH Æ NaCNO + 2NaCl + H2O
2NaCNO + 3Cl2 + 4NaOH Æ 2CO2 + N2 + 6NaCl + 2H2O
(C) Thermal Treatment Process
(i) Incineration It is a thermal treatment process that uses high-temperature
oxidation to convert a waste to a less bulky, less toxic or less noxious material.
Many of the component elements of organic compounds (including C and H)
are converted to gaseous form:
C(Organic) + O2 Æ CO2
4 H(Organic) + O2 Æ 2H2O
Only noncombustible inorganic ash is left behind. Thus, incineration is a
volume-reduction process.
The hazardous products of incineration are compounds of sulphur, nitrogen,
halogen and heavy metals (lead, mercury, arsenic, cadmium, etc). Thus, air-pollution-
control equipment is required if
the gaseous combustion products
of incineration contain undesirable
compounds. Prior to ultimate disposal
or discharge, the solid and liquid
effluents also require treatment.
(a) Performance of Incinerators It
is measured in terms of Destruction
and Removal Efficiency (DRE). It
accounts for both the destruction
in the combustion chamber (s) and
the removal of organics in any air-
pollution-control equipment. DRE
can be calculated as the percentage
of mass difference of input (feed)
and output (stack emission) waste
constituents through the incinerator. Fig. 5.25 Incinerator
example 1 Suppose one gram of an organic compound is released in air

for every 10,000 grams entering the incinerator. Find DRE.
Solution
Input (feed) Output (stack emission)
Mass (g) 10,000 1
10,000 1 1
Per cent ¥ 100 = 100 ¥ 100 = = 0.01
10,000 10,000 100
\ DRE = Percentage of mass difference of input
and output waste constituents
= 100 – 0.01 %
= 99.99 %
Alternative solution for Example 1:
Let DRE = Destruction and Removed Efficiency
A = Mass feed rate = 10,000 grams
B = Mass emission rate = 1 gram
Ê 10,000 - 1ˆ
DRE = ÊÁ
A – Bˆ
¥ 100 % = Á ¥ 100 %
Ë A ˜¯ Ë 10,000 ˜¯
9,999
= % = 99.99 %
100
example 2 A mixture described below is being incinerated at 200°F with

50% excess air and a residence time of 2.1 seconds. Calculate DRE for all organic
compounds.
Compound A = Inlet mass flow rate (lb/h) B = Outlet mass flow rate (lb/h)
Benzene 2015 0.537
Toluene 637 0.022
xylene 3040 1.25
Solution
DRE = ÊÁ A – B ˆ˜ ¥ 100 %
Ë A ¯
È 2015 – 0.537 ˘
For Benzene, DRE = Í
Î 2015 ˙˚ ¥ 100% = 99.9733%
È 637 - 0.022 ˘
For Toluene, DRE = Í
Î 637 ˙˚ ¥ 100% = 99.9965%
È 3040 – 1.25 ˘
For xylene, DRE = Í ¥ 100% = 99.9589%
Î 3040 ˙˚
Notes:
∑ DRE is defined on a compound-specific basis. It is calculated and specified
for each constituent of interest separately.
∑ According to Resource Conservation and Recovery Act (RCRA)
requirements:
Compound Minimum DRE
(a) Organic Compounds 99.99
(b) Dioxins, Dibenzo-furans 99.9999
(b) Advantages of Incineration

∑ Reasonably well-developed technology is available.
∑ Land requirement is not large.
∑ Tetragens (causing birth defects), mutagens (causing mutation in genes), and
carcinogens (cancer causing) can all be completely detoxified in a properly
operated incinerator.
∑ It is the best-known method for the disposal of mixed wastes.
∑ It is an excellent disposal method for biological hazardous wastes.
∑ It can be scaled up easily to handle large volumes of liquid waste.
(c) Disadvantages of Incineration
∑ Substances which volatilise at temperatures below 2000 °F are added in the
air and cause air pollution.
∑ Incinerator is costly.
∑ The gaseous and particulate products of combustion may be hazardous and
should be controlled by air-pollution-control technology.
∑ The ash may or may not be toxic, but it must be disposed of properly.
(ii) Wet-air Oxidation It is the aqueous phase oxidation of dissolved or
suspended organic substances at elevated temperatures and pressures.
Water makes up the bulk of the aqueous phase and serves to catalyse the oxidation
reactions which proceed at temperatures of 150–325°C. The high pressures (2000
kPa to 20,000 kPa) allow high concentration of oxygen to be dissolved in water.
This process is used for the removal of cyanide from electroplating waste
solutions.
2Na+ + 2CN– + O2 + 4 H2O Æ 2 Na+ + 2 HCO3– + 2NH3
(D) Biological Treatment Methods Microorganisms degrade certain or-
ganic hazardous wastes using them as nutrients (bioremediation).
Certain plants take up and concentrate metals from soil or water
(phytoremediation).
(E) Hazardous Waste Landfill It is a type of facility that is reserved for the
disposal of toxic waste after suitable treatment.
In hazardous waste landfills, the dumping area is protected by using a
double composite liner, for preventing the seepage of waste into the ground.
In addition, all liquids must be

properly contained. The leachate
(the leakage of liquids from the
hazardous waste) that collects over
each double liner is collected in a
series of perforated drainage pipes
and pumped to the surface for
further treatment (Fig. 5.26).
Monitoring facilities must also be
included to check the possibility of
any contamination of groundwater
from the landfill site. Landfills also
have gas vent system with sufficient
vent points so that if methane is
generated, it may be burned off
continuously.
Fig. 5.26 Hazardous waste landfill section
The landfill is sloped to permit adequate run-off so that infiltration is minimised

and thus preventing the rainwater or snow melt from entering the soil. The stress
on the liner material is reduced by providing slopes to the landfill at a maximum
of 3:1.
5.11 NUCLEAR HAZARDS (RADIATION POLLUTION)

Radiation is a form of energy that can travel through any medium including vacuum.
It is of two types:
Ionising radiation carries greater energy and can ionise atoms and molecules to
create ions. It can travel both as particles like a and b rays, or as a waves like X-rays,
gamma rays, etc.
Non-ionising radiation carries lower energy than ionising radiation and so it
cannot ionise atoms and molecules. Radio waves, heat and light are examples of
non-ionising radiation.
Nuclear hazard, or radiation pollution, is the danger or risk to human health or
the environment posed by radiation emanating from the atomic nuclei of a radioactive
substance or the possibility of an uncontrolled explosion originating from a fission or
fusion reaction of atomic nuclei.
Nuclear hazards following an accidental release of radioactivity from a nuclear
reactor are illustrated in Fig. 5.27.
Nuclear hazards are caused by the addition of more ionising radiation to the
environment and people are exposed to more radiation than they normally
experience.
Huge clouds of fine radioactive particles and gases are thrown up in the
environment, due to testing of nuclear weapons or disposal of radioactive wastes.
These clouds of fine radioactive particles are carried away to distant areas by winds.
Fig. 5.27 Nuclear (or radiological) hazards following an

accidental release of radioactivity
Gradually, they settle down on the earth as fall-out or are brought down by rainwater.
When raindrops containing these radioactive particles fall on the earth, radioactivity
is transferred to soil, water, etc., causing soil pollution, water pollution, etc. From
the soil and water, radiation reaches crops, animals and aquatic organisms which
absorb and accumulate them through food chains and may pass them to human
beings.
5.11.1 Sources/Causes of Nuclear Hazards:

Natural and man-made sources of nuclear hazards are briefly described below:
(A) Natural Radioactive Sources
(i) Cosmic Radiation It is a stream of ionising radiation that enters the earth’s
atmosphere from outer space. It consists mainly of protons, alpha particles, and
other atomic nuclei including some high-energy electrons. The intensity of cosmic
rays in the biosphere is low. Therefore, they are not a health hazard. However,
cosmic rays are a major hazard in space.
(ii) Terrestrial Radiation It is long-wave electromagnetic radiation emitted by
naturally radioactive materials on the earth including radon, uranium and thorium.
Humans have been exposed to low levels of radiation from these natural sources
for thousands of years. But it is the man-made sources which are posing a threat to
mankind.
(B) Artificial (or Man-Made) Radioactive Sources
These sources of radioactivity are waste materials that contain radioactive nuclei
produced during the
(i) mining and processing of radioactive ores,
(ii) use of radioactive materials in nuclear weapons,
(iii) use of radioactive isotopes in medical, research and industrial applications, and
(iv) use of radioactive materials in nuclear power plants.
Radioactive materials are composed of unstable atoms. Radioactivity is a process
by which an unstable atom emits radiation until it becomes stable. Radiation cannot
be detected by sight, smell, etc., but it has harmful effects on humans. The longer a
person is exposed to radiation, the greater the risk.
5.11.2 Effects of Nuclear Hazards

The effects of nuclear hazards may be somatic or genetic.
(i) Somatic Effects Somatic Effects of nuclear radiation appear in the exposed
person. The quantity of radiation that leads to the absorption of 100 erg per gram
of the absorbing material is known as Radiation Absorbed Dose (RAD).
When an individual receives an acute dose (typically ≥ 10 RAD) in a short period
of time, prompt somatic effects occurs.
For example, a dose of 400 RAD to the scalp results in temporary hair loss which
occurs about three weeks after exposure. New hair is expected to grow within two
months after the dose although the colour and texture may be different.
When an individual receives a small dose, delayed somatic effects are observed
years after irradiation, for example, development of cataracts and cancer.
(ii) Genetic (or Heritable) Effects These effects appear as abnormalities in the
future generations of the exposed person as a result of radiation damage to the
reproductive cells.
Types of Radiation Doses
Potential biological effects of radiation depend on how much and how fast a radiation
is received. Radiation doses can be grouped into the following two types:
(i) Acute Dose A large dose (≥ 10 RAD) to the complete body delivered during
a short period of time (~few days) is known as an acute radiation dose. It may result
in effects which are observable within a period of days to weeks.
A pattern of clearly identifiable symptoms (syndromes) are caused by acute dose.
These are known as acute radiation syndromes. The effects caused by acute doses are
deterministic. It means the dose has some threshold level below which the effect will
probably not occur, but above which the effect is expected. When the dose is above
the threshold level, the severity of the effect increases as the dose increases.
Effects from an acute dose include the following:

(a) 50 RAD to the thyroid gland can result in benign (noncancerous) tumors.
(b) At > 100 RAD, damage to cells that divide at a fast rate (such as bone marrow,
the spleen and lymphatic tissue) happens. It results in internal bleeding,
fatigue, bacterial infections and fever.
(c) At 200 to 300 RAD, irradiation to the skin can result in the reddening of
skin, damage to hair folicles and hair loss.
(d) At 125 to 200 RAD, the ovaries can result in prolonged or permanent
suppression of menstruation in about 50% of women.
(e) At 600 RAD, the ovaries or testicles can result in permanent sterilisation.
(f) At > 1000 RAD, cells that divide less rapidly are damaged. These are cells
in the linings of the stomach and intestines. It causes nausea, vomiting,
diarrhoea, dehydration, electrolytic imbalance, loss of digestion ability,
bleeding ulcers, etc.
(g) At > 5000 RAD, nerve cells (and other cells that do not reproduce) are
damaged. It results in loss of coordination, confusion, coma, shock, etc. As
a consequence, complications caused by internal bleeding, and fluid and
pressure build-up on the brain result in death.
(ii) Chronic Dose It is a relatively small amount of radiation received over a long
period of time. As smaller percentage of the cells need repair at any given time, the
body has time to repair damage. Thus, the body is better equipped to tolerate a
chronic dose than an acute dose.
5.11.3 Control Measures of Nuclear Hazards
Nuclear hazards can be controlled by practicising the following measures:
(i) Nuclear power plants should be located far from populated areas and should
be provided with a suitable radiation-absorption zone around them to
minimise the escape of radiation.
(ii) Safety measures should be enforced strictly to avoid nuclear accidents and
occupational exposure.
(iii) Waste disposal must be effective, careful and efficient,
(iv) The following should be totally stopped:
Leakages from nuclear reactors, careless handling, transport and use of
radioactive fuels and/or radioactive isotopes.
(v) Nuclear wastes have to be properly disposed off.
High-Level Wastes (HLW) like spent nuclear fuel have a very high radioactivity
per unit volume. These are very dangerous. These wastes must be contained
either by converting them into inert solids (ceramics) and then burying deep
into earth or storing in deep salt mines.
Filters, reactor components, etc., are Medium-Level Wastes (MLW). These
are solidified and mixed with concrete in steel drums before being buried in
deep mines or below the sea bed in concentrate chambers.
Solids or liquids contaminated with traces of radioactivity are Low-Level
Wastes (LLW). They are disposed of in steel drums in concrete-lined trenches
in designated sites.
(vi) After the disposal of nuclear waste, drilling activity must be prevented in and
around the disposal site, and radioactivity must be monitored periodically
around the disposal sites.
5.12 SOLID WASTE AND ITS MANAGEMENT

5.12.1 Solid Waste
The waste materials which have been rejected for further use and which can neither
readily escape into the atmosphere nor can be transported by water into streams are called
solid waste.
All the discarded solid materials from municipal, agricultural and industrial
activities are included in solid wastes.
5.12.2 Types and Sources of Solid Wastes

The various types of solid wastes are briefly described below:
(A) Municipal Wastes These include garbage (i.e. biodegradable food waste),
rubbish (i.e. nonbiodegradable solid waste from homes, offices, markets, hotels, etc.).
Construction and Demolition Wastes: Sludges from septic tanks; wires; conduits pipes;
ashes; abandoned vehicles, etc.
(B) Special Wastes These include hazardous wastes like toxic substances (pes-
ticides, heavy metal sludges); radioactive wastes; biological waste; explosives, inflam-
mable substances, corrosive materials, etc.
(C) Domestic Wastes These include wastes generated from domestic cooking
and serving of food.
Examples Garbage, waste paper, plastic, cloth, etc.
(D) Agricultural Wastes These wastes result from farms, feed lots and live-
stock yards.
Examples Corn residues, baggasse from sugarcane manures, paddy husk, etc.
(E) Industrial Wastes These include the following:
(i) Process Wastes Here, waste depends on the products being manufactured.
Examples Plastic wastes, rubber wastes, metal scraps, food-processing wastes, etc.
(ii) Non-process Wastes Here, waste is common to all industries.
Examples Office and cafeteria wastes, packing wastes, etc.
(F) E-Waste It is a new form of waste from discarded mobile phones, mobile
chargers, remotes, CDs, headphones, batteries, computers/TVs, monitors, printers,
CPUs, LCD/Plasma TVs, etc. It is also known as electronic waste.
About 11,000 metric tonnes of E-waste is generated in Delhi annually (Hindustan
Times, March 12, 2010). A recent report has labelled India as the second biggest
E-waste contributor in Asia.
5.12.3 Causes of Generation of Solid Wastes

The main causes for the rapid growth in the quantity of solid-waste generation are
described below:
(i) Overpopulation Solid waste generated per person multiplied by total
population results in increased generation of solid waste every day.
(ii) Urbanisation Urbanisation requires various construction activities like
construction of buildings, markets, shopping malls, roads, railways, airports,
bridges, dams, water supply and sewage disposal systems. Each construction activity
also generates solid wastes.
(iii) Affluence Consumers with high purchasing capacity discard ‘obsolete
goods’. This leads to solid waste generation.
(iv) Advances in Technology These lead to large-scale production of goods
for consumption-based society preferring disposable items and almost every item
‘packaged’. All these results in generation of huge quantities of solid wastes.
5.12.4 Effects of Solid Wastes

The accumulation and improper handling of solid wastes results in various health
and environmental hazards. Some of these effects are described below:
(i) Flies and mosquitoes breed on choked drains and gully pits through solid
wastes. These flies and mosquitoes then contaminate food and water. In
turn, diseases like diarrhoea, amoebic dysentery, bacillary dysentery, malaria,
dengue, etc. result.
(ii) Stray animals and scavengers invade the roadside garbage dumps. It results
in harming the aesthetic beauty of the surroundings.
(iii) Bad odours pollute the air as a result of decomposition of organic solid wastes.
(iv) Percolation of decomposed garbage cause pollution of underground water
and land. The crops and water supply get contaminated and result in
occurrence of cholera, hepatitis, jaundice, gastro-intestinal diseases.
(v) Rats living in solid waste dumping sites rapidly multiply in numbers and
may cause plague and other diseases.
(vi) E-waste is either burnt or buried, So it can have harmful effects on the
environment. This is because E-waste contains many hazardous materials
like lead, mercury, cadmium, flame retardants, etc.
5.12.5 Solid-Waste Management

Important solid-waste management practices are briefly described below:
(i) Source Reduction It involves changing the design manufacture or use of
products and materials to reduce the amounts of solid-waste generation.
Examples Two-sided copying of paper, backyard composting, etc.
(ii) Recycling From the wastestream; paper/glass/plastic/metal, etc., are sorted,
collected, processed and then manufactured, sold and purchased as new products.
Advantages Energy saving, prevention of emission of many greenhouse gases/

water pollutants, job creation, resource conservation for future and reduced need of
new landfills and incinerators.
(iii) Treatment Suitable treatment is given depending on the nature of solid wastes.
(iv) Disposal Solid wastes can be disposed in combustion facilities and land
fills.
The most preferred method for solid waste management is source reduction
(including reuse). It is followed by recycling and composting. Lastly, disposal of
solid waste is done.
A hierarchy of waste management is illustrated in Fig 5.28.
Fig. 5.28 Waste-management hierarchy
5.12.6 Solid-Waste Disposal

The various methods commonly employed for disposal of solid waste are explained
below.
(A) Composting Composting is the thermophilic and aerobic decomposition of
organic matter present in solid waste by microorganisms, mainly bacteria and fungi. As
a result of this composting process, the organic matter is transformed into a stable
humuslike substance, which is a valuable manure for crops.
(i) Classification of Composting Techniques Based on Oxygen Use
(a) Aerobic Composting It requires high temperature and results in rapid
decomposition of organic matter. Odours are also absent.
(b) Anaerobic Composting It requires low temperatures. Decomposition of
organic matter of solid waste is slow. It needs minimum attention.
(ii) Vermicomposting It uses a special kind of earthworm and a container of food
scraps. After some time, the food is replaced with worm droppings, a rich brown
matter that serves as excellent natural plant food (manure).
Advantages of Vermicomposting Over Conventional Composting
∑ Vermicomposting needs less space than normal composting.
∑ Vermicomposting is ideal for apartments in high-density urban areas.
∑ Vermicomposting provides excellent natural plant food.
(B) Illegal Dumping/Open Dumping/Fly Dumping/Midnight Dumping

It is the disposal of solid waste by dumping in open areas, dumped from vehicles
along roadsides, and/or dumped late at night.
(i) Advantages It is done to avoid either the time and effort required for proper
disposal or to avoid disposal fees.
(ii) Disadvantages
(a) Illegal dumping of nonhazardous wastes often attract more waste, even the
hazardous wastes.
(b) Illegal dump sites divert land from more productive uses.
(c) Property values decrease as a result of illegal dumping.
(d) Public nuisance is created by illegal dump sites.
(C) Land Dumping
Solid wastes are dumped in low-lying areas outside the city/town limits. These areas
have no provision of leachate collection and treatment. Moreover, landfill gas is
neither collected nor used.
(i) Advantages
(a) It requires no planning.
(b) It is cheaper.
(ii) Disadvantages
(a) The waste is untreated, uncovered and not segregated. It is the breeding
ground for flies, other insects, rats, etc., that spread diseases.
(b) Rainwater run-off from these dump sites contaminates nearby land and
water thereby spreading diseases.
(D) Landfills
A landfill site is a pit that is dug in the ground. The solid waste is dumped and the
pit is covered with a layer of soil to form a cell. The process is repeated every day
so that many cells completely fill the landfill site. Finally, about 1 m of earth-layer
covering is done.
(i) Advantages
(a) Breeding of insects is prevented.
(b) Landfill sites can be developed as parks or parking spaces.
(ii) Disadvantages
All types of wastes are dumped in landfill sites without segregation. When rainwater
seeps through them, it gets contaminated and in turn pollutes the surrounding area
and groundwater.
(E) Sanitary Landfills

Sanitary landfill sites have liner systems and other safeguards to prevent groundwater
contamination. These sites are consistent with the economic considerations,
hydrogeological requirements, climatic conditions and topography.
(a)
(a) A clay barrier and plastic liner is installed at the base of the ground to prevent water and soil
contamination.
(b) Solid waste is compacted, spread and covered with a layer of soil to form a cell.
Each cell is equipped with a gas vent to collect methane gas formed for further use.
Leachate is the liquid (say rainwater) that seeps through solid waste and has extracts of
dissolved or suspended material from it.
Leachate collection system consists of perforated pipes in a layer of sand. It helps in
collection of leachate.
Many cells are made one above the another in a scientific way.
(c) The top cell is covered with about 1m of earth layer to prevent breeding of pests and disease
vectors.
(b)
Fig. 5.29 Sanitary landfill

(i) Advantages
(a) The site is well above the groundwater table; so underground water pollution
is avoided.
(b) The site is easily accessible; so the process is low in cost.
(c) The site is at least 1.5 km downwind from the commercial and residential
areas; so it is not offensive to the surrounding environment.
(d) The finished sanitary landfill can be used for the development of regions of
recreation like parks, golf courses, etc.
(ii) Disadvantages
(a) Leachate from sanitary landfill site can contaminate the groundwater.
(b) The sites cannot be used in future as productive farmland.
(c) In a sanitary landfill, about 60% of methane gas (odourless) is generated.
When its concentration in air reaches about 5%, it is explosive and so very
hazardous.
(d) Aesthetic problems may arise as a result of poorly operated landfill operations.
(F) Combustion
Solid waste is burned at high temperature in combustion facilities.
(i) Advantages
(a) Energy is generated.
(b) Amount of waste is reduced by up to 90% in volume and 75% in weight.
(ii) Disadvantages
(a) Cost increases with rise in the moisture content of solid waste. This is because
energy is required for preheating the solid waste.
(b) Ash formed after combustion has high concentrations of dangerous toxins
such as dioxins and heavy metals. It results in air and water pollution.
(G) Incineration
It is the controlled combustion of organic solid wastes so as to convert them into
incombustible residue and gaseous products. The weight and volume of solid waste is
reduced and often energy is also produced.
(i) Advantages
(a) As the volume of the waste is reduced, in taking the waste to the ultimate
disposal site, less transportation cost is required.
(b) Larger wastes can be accommodated in a given landfill area because
incineration reduces the land requirement to one-third.
(ii) Disadvantages
(a) Not applicable for radioactive wastes
(b) High capital and operational costs
(c) Air pollution chances if incineration is not properly done
(d) Highly trained manpower is needed
5.13 ROLE OF INDIVIDUALS IN POLLUTION

PREVENTION
Instead of complaining about the deteriorating environmental situation, individuals
can play a very important role in pollution prevention.
Individuals can adopt the following activities in their daily routines for prevention
of pollution:
(i) Whenever feasible, preferably use public transport, car pools and cycles
instead of your own automobiles.
(ii) Purchase and use energy-efficient and pollution-free
(a) vehicles
(b) appliances (like refrigerators, ACs, etc.)
(c) rechargeable batteries, etc.
(iii) Plant trees and help in afforestation.
(iv) Conserve natural resources; save water/electricity.
(v) Reduce consumption, waste generation, water leakages, etc.
(vi) Reuse paper and various products.
(vii) Recycle paper, metal, plastic, etc.
(viii) Refuse to buy and use toxic pesticides, fertilisers, lead-based paints, products
without recycling symbol, products with unnecessary packaging, etc.
(ix) Don’t pollute air, water, soil, etc.
(x) Advocate and participate in environment-friendly activities.
5.14 DISASTER MANAGEMENT

Disaster can be defined as a man-made or natural event (like floods, earthquake, cyclone
or landslides) which results in great damage or loss of life.
A disaster is a consequence of inappropriately managed risk. The risk is the
product of hazard and vulnerability.
Disaster = Risk – Capacity
or Disaster = [Hazard ¥ Vulnerability] – [Capacity of the community]
Hazard is a situation which poses a level of threat to life, health, property
or a dangerous condition or event that may deleteriously affect society or an
environment.
Vulnerability is the extent to which damage will likely happen by the impact of
a particular hazard.
Capacity means resources and strengths which exist in households and communi-
ties and enable them to cope with, withstand, prepare for, prevent or quickly recover
from a disaster.
Fig. 5.30 Classification of Disasters
Risk = (Probability of the accident occurring) ¥ (Expected loss in case of accident)

Thus, risk is a measure of the expected losses due to a hazard event occurring in
a given area over a specified time period.
Realisation of Risk is Disaster
Note: The term disaster is derived from a French word meaning bad or evil star.
Disaster management is the practice of successful management of natural and
man-made disasters.
The major objective of disaster management is to reduce the adverse effects of a
disaster on the affected community and to help them return to normal life within
the shortest possible time.
Hazard
Damage potential
Awareness-
effect on
elements
Society
Action plan
Elements at risk
[Natural (like river); societal (like people)]
Reduced
losses
Damages/Huge losses
More stable More resilient Quicker

society communities recovery
Fig. 5.31 Disaster and its management

Fig. 5.32 Disaster management cycle (the 4 R's)
(i) Response It includes activities during a disaster such as public warning systems,
emergency operations, search, rescue (i.e. save life) and relief (i.e., food aid).
(ii) Recovery It includes activities following a disaster like rehabilitation and
reconstruction which includes temporary housing; processing of insurance claims;
distribution of grants; provisions for long-term medical care and counselling.
(iii) Mitigation or Reduction It includes activities that reduce the effects of
disasters like building codes and zoning, vulnerability analyses; public education.
(iv) Preparedness or Readiness It includes activities prior to a disaster like
preparation of emergency plans for disasters, emergency training through workshops;
warning systems, etc.
To sum up, disaster management means the organisation and management of
resources and responsibilities for dealing with all humanitarian aspects of emergencies,
in particular response, recovery, reduction and readiness, for reducing the impact of
disasters, i.e. the 4R’s.
example 3 Comment on the following statement:

(a) Flood is a hazard, but it may or may not become a disaster.
(b) Humans are all vulnerable in different degrees to various hazards.
Solution (a) The given statement is TRUE.
Flood is a hazard, but it becomes a disaster when people are not ready to cope
with it. Then it may result in loss of livelihood or property.
However, when houses are built to make them flood resistant, people are
evacuated along with valuables to a safe shelter and cattle are moved to hilly areas
then flood remains a hazard and does not become a disaster.
(b) The given statement is TRUE.
∑ People living in the Ganga–Brahmaputra plain are vulnerable to floods.
∑ People living in dry areas of Rajasthan and Western Orissa are vulnerable to
drought.
∑ People living in the Himalayan regions are vulnerable to earthquakes.
Thus, humans are easily exposed to danger or attack and so they are all vulnerable
in different degrees to various hazards.
5.14.1 Flood
Flood is an overflowing of water onto
land that is normally dry. As a result of
flood, the land is filled with an excess
of water (Fig. 5.33).
(A) Causes of Floods

A flood is caused by continuous Fig. 5.33 Flood situation: Relatively high
heavy rain, bad drainage facility, poor stream flow overtopping the natural or
design in the construction of dams/ artificial banks in any reach of a stream
embankments, etc., blocking of river channels by landslides, silting of river bed,
tsunami, cyclones, and melting of glaciers and sea tides.
(B) Types of Floods Depending on the cause, floods are of the following types:
(i) When a flood occurs within a short period of time, usually less than 6 hours,
because of dam burst, melting of snow, heavy rains, etc., it is known as a flash
flood.
(ii) When a flood takes place in urban areas because of lack of proper drainage
facilities, it is known as an urban flood.
(iii) When a flood is caused by tides, storms at sea, cyclone and tsunami, it is
known as a coastal flood.
(iv) When a flood is caused by an overflowing river, it is known as a riverine flood.
example 4 Explain how flood is caused by (a) heavy rain, (b) deforestation,
and (c) soil erosion.
Solution
(a) The monsoon climate brings very heavy rain, which results in overflowing
rivers. Excess water is not readily absorbed or stored within the drainage
basin; so flood is caused.
(b) Trees are cleared for fuel and grazing land in deforestation. As less trees are
available on land, evapotranspiration is less, and run-off is more. Thus, flood
is caused.
(c) Rivers silt up due to increased soil erosion. This raises the river bed and
reduces the capacity of the channel. As a result of this, the likelihood of
flooding is increased.
(C) Effects of Floods

(i) Unavailability of Clean Water Water in wells, groundwater and piped water
supply gets contaminated as a result of flood, resulting in shortages of clean water.
(ii) Damage to Crops and Food Shortages Standing crops are damaged by
flood. Flood can erode the top soil layer causing land to become infertile. If sea
water floods the area, the land turns saline.
As a result of floods, godown and storage facilities get submerged in water

resulting in spoilage of grains by fungus. Even entire harvests are lost as a result of
flood resulting in sudden food shortages.
(iii) Diseases and Deaths Floods result in outbreaks of epidemics, diarrhoea,
malaria and viral infections. Animals and humans die either due to these diseases or
due to drowning.
(iv) Physical Damage In coastal areas, boats or fishing equipments may be lost
or damaged. Property gets damaged or collapsed by flooding.
(D) Flood Management Management of flood requires a cyclic pattern linking
(i) Planning: ideas, proposals, con-
sultations, adopting proposals,
preparing guidelines;
(ii) Design: design of flood control
structure;
(iii) Implementation: construction;
and
(iv) Operation: operating and main-
taining finalised schemes. Fig. 5.34 Flood Management Cycle (PDIO)
A flood-management cycle is illus-
trated in Fig. 5.34.
∑ At the planning level, proposed
flood mitigation options are as-
sessed and environmental im-
pact assessments are prepared.
∑ At the design stage, civil works
design criteria is determined,
Flood Control and Drainage
(FCD) structure is designed.
Even inputs to flood prepared-
ness programmes are provided
at the design stage.
∑ At the implemention stage,
flood prone-construction work
is started; help is also given for
flood preparedness training.
∑ At the operation stage, flood
control and drainage structures
are built by taking helps of
flood forecasting. Emergency
relief operations are also assist-
ed in the operations stage (Fig. Fig. 5.35 Operation stage of flood
5.35). management
(E) Flood-Control Measures Technological skills, better warning systems,

positive human response to flood warnings and various control measures adopted
by the government helps in minimising the impacts of floods.
Notes: In India, the Central Water Commission (CWC) is equipped with 157
flood forecasting centres covering 62 interstate river basins. In collaboration with
the Indian Meterological Department (IMD), these flood forecasting centres
monitor rainfall situations and water levels in reservoirs. This information helps
the CWC to issue forecast and warning about floods.
Some of the important flood-control measures are briefly described below:
Fig. 5.36 Food control measures

(i) Flood Proofing In flood-prone areas, artificial reservoirs can be built to divert
flood water into a certain direction.
(ii) Afforestation In the hilly source catchment areas of rivers, afforestation
helps in infiltration of rainwater, reduction of the soil erosion and reduction in the
sediment load of the river.
(iii) Artificial Straightening of Channels It is a very useful strategy for flood
control because water flows speedily during floods in straight channels.
(iv) Elevations and Platforms These structures help in preventing the flood
water from entering residential areas (Fig. 5.37).
(a) Flood barriers for doorways

(b) Covers for airbricks and other wall
vents
(c) Improved resistance of floors and
walls to prevent water ingress
(d) Valve to prevent backflow
(e) Elevations for preventing the flood
water from entering the house
Fig. 5.37 Elevations and barriers for flood-risk minimisation

Flow of water can be blocked by using sand bags.
(F) Flood Disaster Management Maps To mitigate flood disasters, a flood
disaster management map contains following informations:
(i) Information on flood inundation areas predicted by possible overflows in
rivers due to heavy rain, etc. The prediction can be based on historical flood
damage records and by scientific predictions.
This information provides flood hazard and vulnerable areas against floods
in the community [refer Fig. 5.38(a) Flood Hazard Map (FHM)], A = 1st
Day; B = 2nd Day; C = 3rd; D = 4th Day; Inundation Areas
(ii) Information to provide flood disaster mitigation and information for
protecting lives such as initiation time of inundation, inundation area,
inundation depth, velocity of river water flow.
(iii) Evacuation sites, flood shelters, evacuation routes, etc. [refer Fig-5.38(b)
Flood Disaster Management Map (FDMM)].
Fig. 5.38 (a) Flood Hazard Map (b) Flood Disaster Management Map
In general, an FDMM contains information about

(a) hazard, (b) evacuation, (c) disaster awareness raising, and (d) disaster
management.
(G) Guidelines for Preparing Flood Disaster Management Map
(i) Investigate historical flood damage records, seek scientific advice and
guidance as scientists can do numerical simulation of possible floods.
(ii) Estimate inundation prediction area.
(iii) Display inundation prediction area as a hazard risk area in the Flood Hazard
Map (FHM)
(iv) Add disaster mitigation information such as
(a) basic knowledge of flood
(b) disaster prevention facilities
(c) evacuation tips
(d) evacuation sites and routes
By adding the above information in FHM, flood disaster management
maps (FDMM) are constructed.
Information on the map is presented in a comprehensive but easy-to-
understand manner. The following information could be included in an
FDMM:
(a) Telephone number of authorities related to disaster management (police,
hospital, fire department, etc.)
(b) Disaster prevention centers
(c) Land use
(d) Power, gas and water supply facilities, and sewerage facilities
(e) Elementary schools

(f) Others
(v) The flood disaster management map must be prepared in the workshops
together with local residents, schools and scientific representatives:
(a) To reflect local information
(b) To promote the understanding of inundation areas and evacuation sites
(c) To facilitate well-prepared persons for flood rescue teams
(d) To establish the importance of the map within the community from
childhood
(e) To provide a chance for family members to talk about disaster prevention
and mitigation
(f) To promote more precise flood disaster management maps in flood-
prone villages.
(H) Usefulness of Flood Disaster Management Map
These maps can be used for
(i) planning of preventive measures,
(ii) integration of land use planning,
(iii) evacuation,
(iv) construction of required protection facilities,
(v) evaluating the effects of structural measures, and
(vi) increasing the people’s self-protecting capability against disaster.
To sum up
A Flood disaster management map provides necessary graphical information
about regional flood hazards and vulnerability
∑ to manage flood disasters
∑ to minimise damage in the region
A Flood disaster management map is a crucial tool to investigate and establish
comprehensive disaster mitigation systems.
example 5 Enumerate economic, environmental, political, social and

cultural factors for reducing flood risk.
Solution (a) Economic
∑ Insurance
∑ Risk management as a normal part of business
∑ Sustainable flood-plan development
(b) Environmental
∑ Working with natural processes and systems
∑ Climate change
∑ Protecting life-supporting capacities and ecological values

∑ Integrated catchment management
(c) Political
∑ Adaptive and responsive to change
∑ Agreed roles and responsibilities
∑ Common long-term goals
∑ Long-term outcomes
(d) Social and Cultural
∑ People understand and accept the level of flood risk.
∑ Non-structural, structural and emergency management measures
∑ Risk management
example 6 What are the requirements for good flood-risk management?

Solution The requirements for good flood-risk management are summarized
below:
(a) Political will
(b) Approved goal of risk reduction
(c) Resources
(d) Guidance
(e) Government policies and legislative framework to support risk management
(f) Availability of required information
(g) Monitoring
(h) Evaluation
(i) National capacity in allied fields
(j) Cooperation from society
example 7 What are the drivers against good flood-risk management?

Solution The drivers against good flood-risk management are summarised
below:
(a) Unwillingness to pay
(b) Lack of resources, capacity and required information
(c) Vested interests
(d) Inertia and inability to change
(e) Not bearing the full cost of management
example 8 Enumerate economic environmental, political, social and

cultural factors which cause increased flood risk.
Solution (a) Economic
∑ Under-insurance
∑ Underestimated financial cost of flooding
∑ Urban and rural development at risk
(b) Environmental
∑ Ignorance of natural processes.
∑ Ignorance about probability of large floods
∑ Ignorance of climate change and variability
(c) Political
∑ Focus only on short-term outcomes
∑ Desire for short-term visible actions and achievable goals
∑ Enabling legislation with no explicit goals: social and cultural
(d) Social and Cultural
∑ Flood management is not considered as community need
∑ Non-sufficient protection of people and assets
∑ Past decisions not reviewed
∑ Over-reliance on engineering and hazard control
example 9 Illustrate prevention, response and recovery activities of

flood management using a simple diagram.
Solution
5.14.2 Earthquake
An earthquake is the vibration (sometimes violent) of the earth’s surface that follows a
release of energy in the earth’s crust.
Tectonic earthquake is caused by the sudden dislocation of large rock masses along
the faults within the earth’s crust. A fault is a fracture within some particular rocky
mass within the earth’s crust. Faults along which the two sides of the fracture move
with respect to each other are known as active faults. Earthquakes are caused by
active faults. Depending on the movement of two sides of fracture, faults can be of
following three types:
(i) In response to pulling or tension, normal faults occur. The overlying block
moves down the dip of the fault plane.
(ii) In response to squeezing or compression, thrust (reverse) faults occur. The
overlying block moves up the dip of the fault plane.
(iii) In response to either type of stress, strike-slip (lateral) faults occur.
Fig. 5.39 (a) Normal fault (b) Thrust fault (c) Strike slip fault
The focus is the point or centre where the energy release starts. The epicentre is the
point on the earth’s surface directly above the focus of the earthquake.
The slow and continuous movement of two sides of an active fault relative to
one another (called fault slip), results in gradual build-up of elastic strain energy
within the rock along the fault. The rock stores this strain like a giant spring being
slowly tightened. At some
stage, the build of strain will
be too much for the rock to
bear. The fault then suddenly
moves a comparatively large
distance in a short duration.
The rocky masses which form
the two sides of the fault then
snap into a new position
along with release of the
strain energy. This suddenly
released energy takes the form Fig. 5.40 Earthquake
of seismic waves.
2
Thus, seismic waves are the waves of energy
caused by the sudden breaking of rock within
1
the earth or an explosion. Epicentre
An earthquake radiates body waves in all 2 Focus
directions. These are compressional or primary
1
(P) and transverse or secondary (S) waves. The Earth
interaction of the P and S waves with the earth’s 1. Body waves
2. Surface waves
surface and shallow structure produces surface
waves. Fig.5.41 Seismic waves
Fig. 5.42 The P waves, S waves and surface waves shake the ground in different
ways and also travel through the earth at different velocities
The seismometer must be able to move
with the vibrations of seismic waves, yet part
of it must remain nearly stationary. This is
achieved by isolating the recording device
(say pen) from the rest of the earth using
the principle of inertia. For this, a pen is at-
tached to a heavy mass which is suspended
by a spring. Paper is attached to the earth.
During an earthquake, the paper moves
more than the pen and heavy mass, and so
vibrations get recorded on the paper.
The size of an earthquake is generally
given in terms of the Richter magnitude.
It is a scale of earthquake size developed Fig. 5.43 The machine used to measure
earthquakes is known as Seismometer
by the seismologist Conrad Richter.
Fig. 5.44 The Richter magnitude involves measuring the amplitude (height) of
the largest recorded wave at a specific distance from the earthquake.
It is logarithm scale. For each increase of 1 in the Richter magnitude,
there is a tenfold increase in amplitude of the wave
The amount of energy released (E) in ergs by the earthquake is related to the
Richter magnitude (M) by the following equation:
log E = 11.8 + 1.5M (5.3)
example 10 Find the amount of energy released in ergs when the

earthquake has magnitudes of 8 and 9 on the Richter scale.
Solution (a) Given M = 8
As log E = 11.8 + 1.5M
fi log E = 11.8 + 1.5 ¥ 8
fi log E = 23.8
fi E = antilog (23.8)
fi E = 6.3 ¥ 1023 ergs (1)
(b) When M = 9
fi log E = 11.8 + 1.5 ¥ 9
fi log E = 25.3
fi E = antilog (25.3)
fi E = 1.995 ¥ 1025 ergs (2)
Dividing Eqn. (2) with Eqn. (1), we get
1.995 ¥ 1025
= 31.6
6.3 ¥ 1023
Thus, an earthquake of magnitude 9 releases 31 times more energy than an earthquake
of magnitude 8.
Notes:
(i) An amount of energy released by Hiroshima atomic bomb was equivalent
to a magnitude of 5.5 earthquake.
(ii) In 1964, the Alaska earthquake had a Richter magnitude of 8.6.
(iii) Sensitive seismographs can greatly magnify earthquake-caused ground
motions. They can detect strong earthquakes from sources anywhere in the
world.
(iv) The magnitude of an earthquake is determined from the logarithm of the
amplitude of waves recorded by seismographs.
5.14.3 Tsunami
In Japanese, tsu means harbour and nami means waves. A tsunami is a series of waves
in the ocean that can be hundreds of miles long and have been known to reach heights
of 10.5 m. The massive December 26, 2004 tsunami travelled at a speed of 480 km
per hour.
Origin of Tsunami The top layer of the earth (i.e, the lithosphere) is made
up of a series of huge plates. They rest on an underlying viscous layer called the
asthenosphere. On the earth, these plates are constantly in motion, moving along
each other at a speed of 2.5 to 5 cm per year. When two plates come into contact
at a plate boundary region, a 1

3
heavier plate can slip under a Upward wave
4
lighter one, resulting in sub- 2
duction. Part of the sea floor
connected to the lighter plate
may ‘snap up’ in some cases. Crust
It sends tons of rock shoot-
ing upward with tremendous Mantle
1 Undersea quake displaces huge amounts of water suddenly
force. When the energy of the
2 Huge shallow waves rush through the sea at up to 650 km/hr
force in transferred to the wa- 3 On reaching a gently slopping coastline the waves slow and compress upwards
ter, water is pushed upwards 4 Waves surge ashore to cause devastation well beyond the beach
above normal sea level. This Fig. 5.45 Cause and effects of undersea
is the birth of a tsunami. earthquake and tsunami
5.14.4 Cyclone
Cyclones are swirling atmospheric disturbance in the form of huge revolving storms caused
by powerful winds moving with very high velocities (sometimes exceeding 300 km/h).
Cyclones are accompanied by rain and generate enormous waves in the ocean.
Notes:
• The word cyclone is derived from the Greek word ‘cyclos’ meaning coils of a snake.
• Cyclones are known as willie-willie in Australia; typhoons in the Pacific
ocean; and hurricanes in the Atlantic ocean.
• Huge storms of cyclones revolve in clockwise direction in the northern
hemisphere and in anti-clockwise direction in the southern hemisphere.
(A) Cause(s) of Cyclones
(1) Near the Equator, over warm seas,
air heated by the sun rises upwards
quickly and creates areas of very low
pressures. (2) To fill the void that is left,
cool air rushes in. (3) We know that the
earth is constantly revolving around its
axis. (4) Thus, the air is bent inwards
and spirals outwards with great force.
(5) As the warm air rises, it becomes
loaded with moisture which condenses
into massive thunderclouds. (6) Due
to the faster and faster rotation of the
swirling winds, a huge circle of clouds
get formed. The edge of a cyclone is
called ‘wall of the eye’ which has a ra-
dius of 20 km–30 km. At the centre of
the cyclone, wind velocity is less. This
calm, cloudless area is called the ‘eye’ of
the cyclone. Fig. 5.46 Cause of cyclones
When cyclones move over the ocean, they drag clouds and moisture. They can
also pick up energy when they travel across warm water. (7) When cyclones move
over land, they result in heavy rains leading to floods.
(B) Effects of a Cyclone Cyclones can cause the following damages:
(i) The standing crop and food stock lying in low-lying areas will be ruined due
to powerful winds and heavy rain. Banana, coconut and other plantation
crops are extremely vulnerable.
(ii) Sea water dragged through cyclones result in inundation of land. This increases
salinity as a consequences of which soil becomes unfit for cultivation.
(iii) Heavy rain can cause flooding. This can lead to contamination of groundwater
and surface water. Viral outbreaks, diarrhoea and malaria are consequences
of contamination of water.
(iv) Gable-ended roofs made from cement, asbestos or tin sheets get high uplift
as a result of powerful winds of cyclones. As these sheets are blown away,
these then strike against nearby buildings, animals and humans causing
damage and deaths.
(v) Asymmetric buildings with empty pockets collapse due to the impacts of
powerful winds.
(vi) Trees get uprooted and carried away along with powerful winds. These,
then, destroy telephone lines, electricity poles, transmission line towers, etc.
Thus, power supply and communication networks get disturbed.
(vii) Cyclones are powerful enough to damage loose or weak parts of buildings
like doors, windows, etc.
(C) Control Measures of Cyclones Control (or protection) measures and
main mitigation strategies are briefly discussed below:
(i) On the coasts of India, 10 cyclone detection radars are installed by India
Metrological Department (IMD). A geo-stationary satellite (INSAT-IB)
also monitors cyclone movements. A special Disaster Warning System
(DWS) provides a cyclone alert (48 hours in advance) and a cyclone warning
(24 hours in advance). Such early warnings help in controlling the damages
of cyclones.
(ii) Symmetrical designs of buildings, no empty pockets, hip or pyramidal roofs,
no loose ACC sheets or tin sheets, reinforced cemented foundations, less wide
doors and windows, etc., are engineered structures better in withstanding
impacts of powerful winds and heavy rains of cyclones.
(iii) Strong rooted trees with needlelike leaves can be planted in the directions
facing the wind along coastline. These shelter-belt plantations lessen the
impact of strong cyclonic winds and thus stop soil erosion. As a result,
houses, cultivable fields, etc., are protected (Fig. 5.47).
(D) Cyclones in India
(i) About two-thirds of the cyclones that occur in the Indian coastline occur in
the Bay of Bengal.
(ii) West Bengal, Orissa, Andhra Pradesh and Tamil Nadu are the Indian states
which are generally affected by cyclones in the east coast.
(iii) Gujarat, Maharashtra, Goa, Karnataka and Kerala are the Indian states
which are generally affected by cyclones in the west coast.
(iv) About 8913 people died as a result of tropical cyclone-hit in Orissa in 1999.
The death toll was 5000 for the 1985 cyclone in Andhra Pradesh. In 1977,
about 14,204 people died as a result of cyclone which hit Chennai, Kerala
and Andhra Pradesh.
(v) India is extremely vulnerable to cyclones and its associated hazards like
high winds, heavy rainfall and storm surge. This is because India has a long
coastline of about 7516 km, flat coastal terrain, high population density and
the vulnerable geographical location.
Fig.5.47 Main mitigation strategies w.r.t. engineered structures

for protection against cyclones
5.14.5 Landslides
Landslide means downward sliding of a relatively dry mass of land and rock. It is also
known as landslip.
(A) Effects of Landslides
(i) Landslides block or bury roads, lines of communication, railways lines, etc.
(ii) They destroy anything that comes in their path. They destroy settlements.
(iii) They destroy agricultural areas leading to loss to food production.

(iv) They block river flow; flooding may also occur.
(v) The flow of debris in landslides causes heavy casualties.
(B) Landslides (Disaster) Management
Main mitigation strategies and preventive measures of landslides are illustrated in
Fig. 5.48 and important solutions are described below:
(i) Grow Trees The most effective way of arresting landslides is afforestation.
Shelter belts with several rows of trees, both on slopes and the bottom, should be
maintained. This helps to bind the top layer of soil with layers below, while preventing
excessive run-off and soil erosion.
1. Landslide risk
management objectives
2. Establish
8. Monitor decision-making criteria
3. Assess risk
No
7. Implement
No
plant 4. Identity 5. Assess solution
solutions cost-benefit
Yes analysis
6. A. Problem defined correctly?
B. Criteria met?
C. Decision Made and plan
prepared?
Fig. 5.48 Important mitigation strategies for landslide risk management
(ii) Stabilise Slopes Build retaining walls along roads in hill stations to stop
land from slipping. Property owners at the toes of steep slopes should construct
reinforced walls as barriers to trap landslides.
(iii) Avoid Blockage of Natural Drainage This should be done in construction
of roads, irrigation canals, etc., when landslides are accompanied by infiltration of
rainwater and spring flows, redirect surface run-off towards safe places through
straight channels.
(iv) Install Flexible Pipes and Cables Underground Flexible pipes and
cables should be installed underground in order to withstand forces caused by the
landslides.
(v) Build Strong Foundations To withstand ground movement forces of
landslides, structures must be engineered with strong foundations.
(vi) Encourage Proper Land Use Vulnerable areas must be protected. Land-
use practice must be improved.
∑ Pollutant is a material which is present in excess of the natural concentration and
produces a bad effect upon the environment.
∑ Pollution or environmental pollution can be defined as an undesirable change in the
physical, chemical or biological characteristics of our environment by the introduction
of substances or energy by humans into the environment.
∑ Air pollution is the presence of substances in the air (which generally originate from
human activities) in sufficient concentrations and sufficient time, to interfere with the
comfort, health, safety or full use and enjoyment of property.
∑ Air pollutants are gaseous, liquid or solid substances present in such concentration as
may be or tend to be injurious to human beings or other living creatures or plants or
the environment.
∑ Water pollution is defined as presence of any foreign substance or energy in water in
such concentration and for such duration that tends to degrade the quality of water
so that humans, animals or any other organism cannot enjoy the beneficial qualities
of water but the use constitutes a hazard.
∑ Waste-water treatment is carried out in the following steps:
(a) Primary Treatment: It helps in the removal of suspended particles.
(b) Secondary Treatment: It helps in the aerobic decomposition of organic matter.
(c) Tertiary Treatment: It helps in the production of safe water, free from harmful
chemicals and pathogenic bacteria.
∑ Soil pollution can be defined as the introduction of substances, biological organisms,
or energy into the soil that lead to a change in the quality of soil so that plant growth
and animal health is adversely affected.
∑ Marine pollution is defined as the direct or indirect discharge of matter or energy
by humans into marine water bodies that is harmful to living organisms, hazardous
to human health, hinders marine activity, adversely affects-sea-water quality and
reduces its amenities.
∑ Noise pollution is defined an environmental noise or an unwanted sound that is
annoying, distracting, or physically harmful. Harms include hearing loss, stress,
sleeplessness, etc. Noise pollution is also known as sound pollution.
∑ Thermal pollution may be defined as the degradation of water quality by any process
that changes ambient water temperature.
∑ Hazardous wastes can be defined as useless, unwanted and discarded material that
may pose a threat to human, plant or animal life.
∑ Radiation is a form of energy that can travel through any medium including vacuum.
∑ Nuclear hazard, or radiation pollution, is the danger or risk to human health or the
environment posed by radiation emanating from the atomic nuclei of a radioactive
substance or the possibility of an uncontrolled explosion originating from a fission or
fusion reaction of atomic nuclei.
∑ The waste materials which have been rejected for further use and which can neither
readily escape into the atmosphere nor can be transported by water into streams are
called solid waste.
∑ Composting is the thermophilic and aerobic decomposition of organic matter present
in solid waste by microorganisms, mainly bacteria and fungi.
∑ Sanitary landfill sites have liner systems and other safeguards to prevent groundwa-
ter contamination. These sites are consistent with the economic considerations, hy-
drogeological requirements, climatic conditions and topography.
∑ Incineration is the controlled combustion of organic solid wastes so as to convert
them into incombustible residue and gaseous products.
∑ Disaster can be defined as a man-made or natural event (like floods, earthquake, cyclone
or landslides) which results in great damage or loss of life.
∑ Hazard is a situation which poses a level of threat to life, health, property or a dangerous
condition or event that may deleteriously affect society or an environment.
∑ Vulnerability is the extent to which damage will likely happen by the impact of a
particular hazard.
∑ Capacity means resources and strengths which exist in households and communities
and enable them to cope with, withstand, prepare for, prevent or quickly recover
from a disaster.
∑ Disaster management is the practice of successful management of natural and man-
made disasters.
∑ The major objective of disaster management is to reduce the adverse effects of a
disaster on the affected community and to help them return to normal life within the
shortest possible time.
∑ Flood is an overflowing of water onto land that is normally dry.
∑ An earthquake is the vibration (sometimes violent) of the earth’s surface that follows
a release of energy in the earth’s crust.
∑ Seismic waves are the waves of energy caused by the sudden breaking of rock within
the earth or an explosion.
∑ A tsunami is a series of waves in the ocean that can be hundreds of miles long and have
been known to reach heights of 10.5 m. The massive December 26, 2004 tsunami
travelled at a speed of 480 km per hour.
∑ Cyclones are swirling atmospheric disturbance in the form of huge revolving storms
caused by powerful winds moving with very high velocities (sometimes exceeding
300 km/h).
∑ Landslide means downward sliding of a relatively dry mass of land and rock. It is also
known as landslip.
EXERCISES
Based on Environmental Pollution Based on Water Pollution
1. What is meant by environmental 1. What do you mean by water pollution?
pollution? Discuss the requirement of a 2. Discuss water treatment with layout
nonpolluted environment. of a water-treatment plant.
2. How can you, as an individual, prevent 3. Suggest various remedial and control
environmental pollution? Why is such measures to minimise water pollution.
an effort at individual level important? 4. What are the common sources of
3. What is pollution? water pollution? Discuss the various
4. Enlist global environmental prob- types of water pollutants.
lems and discuss any one. (b) What are 5. How do synthetic detergents, pes-
the common toxic chemicals in the en- ticides and plant nutrients present as
vironment? water pollutants create problems?
5. What are the causes of environment 6. Write a short note on groundwater
pollution? List all environment pollu- pollution.
tions and their sources in detail. 7. Describe sources of water pollution.
8. What is potable water? Describe the Based on Air Pollution and Air
different water pollutants which make Pollutants
water unfit for drinking. 1. What is air pollution? What are its
9. Define water pollution and enlist effects on human health?
various sources of water pollution. 2. Explain four major air pollutants and
Explain any one in detail. their consequences.
10. What are effects of water pollut- 3. Enumerate various air pollutants
ants on environment and humans? for which National Ambient Air Quality
11. Discuss important characteristics Standards have been given in India.
of waste water. Give the outline of the 4. Explain the various nonpoint sources
waste-water treatment methods. contributing to air pollution.
12. Write classification of water 5. Discuss the measures used for
pollutants with suitable examples. controlling air pollution.
6. Discuss the natural and man-made
Based on Land Pollution
(synthetic) pollutants that cause air
1. Define land pollution. Discuss the
pollution.
causes of land pollution and their
7. What are the sources of (a) NOx and
control.
(b) CO pollution in the atmosphere?
2. Enumerate various effects of
What measures can be adopted to
soil pollution. How do industrial,
control these emissions?
agroproducts and pesticides deteriorate
8. Enlist natural and human sources
the soil?
of air pollution. Explain any one briefly
3. (a) Discus the effect of the following
and list out the common atmospheric
in soil pollution:
pollutants.
(i) Agro technology, (ii) Urban waste
9. Write the characteristics and bio-
(b) Write short notes on
logical effects of the following in air:
(i) Soil profile, (ii) Soil pollution control
(a) SOx (b) NOx (c) CO
4. What is land degradation? What are
10. Discuss the sources and effects of
its causes.
particulates in the atmosphere.
5. What are the effects of soil pollu-
11. Discuss hazardous effects of air
tion?
pollutants.
6. What are the sources of soil pollu-
tion? Based on Solid Waste and its
7. How is the monitoring of soil pollu- Management
tions made? 1. What are ‘solid wastes’? Discuss
8. Mention various/major types of soil their types, effects, and name the
pollution. various methods used to dispose solid
9. Describe uses and overuses of land. wastes. Explain any one of them with
What are causes and effects of land merits and demerits.
pollution? 2. Explain the various methods com-
10. What are the major sources of land monly employed for disposal of solid
pollution? How does land pollution waste, with their advantages and dis-
affect soil productivity? advantages.
11. What are causes of land degrada- 3. Briefly describe the idea of “solid-
tion? Narrate common pollutants re- waste management”. Distinguish be-
sponsible for causing land pollution. tween the incineration and combusting
methods of solid-waste disposal.
4. Classify the composting techniques (c) Explain the effects of oil pollution
based on oxygen use. What are the on the ocean.
advantages of ‘vermicomposting’ over
Based on Noise Pollution
conventional composting? What are
1. Discuss effects of noise pollution
the advantages of solid-waste incinera-
and its control.
tion?
2. Define noise pollution. Describe all
5. What do you understand by the
effects of noise pollution.
term solid waste? Discuss in brief the
3. Define noise. Enlist major sources of
various types of solid wastes.
noise pollution and explain any one briefly.
6. What is solid waste? Discuss its
4. Write an account of decibel scale for
sources and effects.
the measurement of sound.
7. What does the term incineration
5. Write short notes on (a) noise con-
mean? What are its disadvantages?
trol, and (b) speech interference level.
8. What are the advantages and
6. What are physical, physiological and
problems of a sanitary landfill?
psychological effects of noise?
9. How is solid waste segregated?
7. Discuss the harmful effects of noise
10. Discuss the treatment and disposal
pollution. State the measures to control
methods for solid waste.
noise pollution.
11. What are the different types and
sources of waste? Explain the properties Based on Radioactive Pollution
and effects of solid wastes. 1. What are the sources of radioactive
12. Give an informative appraisal on pollution and how can we control the
recycling of solid wastes. radioactive pollution?
2. What are the different methods for
Based on Marine Pollution
treatment of hazardous waste and how
1. What are the sources and effects of
can it be disposed safely?
marine pollution?
3. Write a note on hazardous wastes
2. (a) Oceans are ultimate sinks
and the environmental problems and
for most of the waste we produce.
health risks associated with these.
Explain.
4. Describe the causes of the Chernobyl
(b) List offshore sources of marine
disaster and what are the lessons to be
pollution.
learnt from this incident?

I. Fill in the Blanks 4. _________ is a combination of
1. Automobiles are the largest sources smoke and fog.
of _________ pollution in cities. 5. Taj Mahal at Agra may be damaged
2. PAN is formed by the interaction by _________.
of oxides of nitrogen and _________ in 6. _________ measures dissolved
presence of sunlight. oxygen needed by microbes to
3. Increase in the concentration of decompose organic waste.
soluble salts in _________ is called 7. Air pollution from automobiles can
salinisation. be controlled by fitting _________.
8. _________ (air pollutant) gets 3. 3º treatment (c) Remove (45–

combined with haemoglobin of the 60)% suspended
blood more rapidly than oxygen. solids and (30–45)%
9. Electrostatic precipitators are used BOD
to remove _________.
10. The largest range of sound fre- 4. Septic tanks (d) Removes residu-
quency measured in vibration/second al, volatile and sus-
which humans can hear is _________. pended solids
11. _________ is the most effective III. Multiple Choice Questions
and cheap method of noise control. 1. The gas leaked in Bhopal tragedy
12. World Health Day is recalled on was
_________. (a) methyl isocyanate
II. Match the following terms. (b) ethyl isocyanate
Match the terms of column I with (c) butyl isocyanate
appropriate terms of column II. (d) sodium isocyanate
A. 2. Noise is _______ sound.
(a) constant
Column I Column II (b) unwanted
1. Soil pollution (a) Cancer (c) loud
2. Noise pollution (b) Cooling (d) high frequency
tower 3. The disease caused by eating fish
inhabiting mercury-contaminated wa-
3. Nuclear pollution (c) Fish kills
ter is
4. Thermal pollution (d) Hearing loss (a) cancer
5. Oil pollution (e) Sewage (b) fever
(c) minamata disease
B.
(d) osteosclerosis
Column I Column II 4. Increasing skin cancer and high
1. Asthma and (a) Ozone-layer mutation rate are the result of
bronchitis depletion (a) acid rain
(b) CO2 pollution
2. Absorbtion and (b) Inhalation of
(c) global warming
removal of UV light pollen
(d) ozone depletion
3. Peroxyacetyl (c) Ozone 5. Which of the water samples from
nitrate (PAN) the following four sources have the
4. Skin cancer (d) Secondary excessive quantity of calcium, sulphate,
pollutant magnesium, bicarbonate?
C. (a) River water (b) Lake water
Column I Column II (c) Sea water (d) Well water
6. One among the following is not
1. Grit chamber (a) Treatment of do- essential for biomagnification to take
mestic liquid wastes place. Identify it.
2. 1º sedimen- (b) Removes gravel (a) Phytoplankton
tation tank and sand (b) Animals
(c) Zooplankton 8. Permissible noise level during

(d) Fishes daytime in a residential zone is 55 dB.
7. Eutrophication of surface waters True/False
occur due to the presence of 9. Sludge from a water-treatment
(a) organic carbon plant is a hazardous waste. True/False
(b) pesticides 10. The production, processing and
(c) nutrients distribution of food all changes the
(d) inorganic carbon environment. True/False
11. Desertification is the primary envi-
ronmental effect of agriculture.
following statements
True/False
1. Noise is measured in decibel scale.
12. House is a health hazard when fac-
True/False
tors such as poor design, environmental
2. All pollutants are degradable.
contamination and poverty combine to
True/False
cause or exacerbate disease.
3. Underground water is nonpolluted
True/False
and safe. True/False
13. For the development of a country
4. PAN is a primary pollutant.
and the prosperity of its people, indus-
True/False
try is essential. True/False
5. Ozone causes cracking of rubber.
14. Industrial practices release enor-
True/False
mous quantities of air and water pollut-
6. The residue of fertilisers and
ants. True/False
pesticides ramains for a long time and
15. Transportation activities support
delivers deleterious effects on soil.
increasing mobility demands for
True/False
passengers and freight but at the cost
7. Run-off from land area contributes
of adverse environmental effects.
to marine pollution. True/False
True/False

I. Fill in the Blanks II. Matching the terms.
1. Air A. 1. (e) 2. (d) 3. (a) 4. (b) 5. (c)
2. Hydrocarbons B. 1. (b) 2. (c) 3. (d) 4. (a)
3. Soil C. 1. (b) 2. (c) 3. (d) 4. (a)
4. Smog
5. SO2
1. (a) 2. (b) 3. (c) 4. (d)
6. BOD
5. (a) 6. (b) 7. (c)
7. catalytic converter
8. CO IV. True or False
9. Particulates 1. True 2. False 3. False 4. False
10. 20 to 20,000 5. True 6. True 7. False 8. True
11. Control at source 9. False 10. True 11. False 12. False
12. April, 7th 13. True 14. True 15. True
6
SOCIAL ISSUES
AND THE
ENVIRONMENT
Learning Objectives
∑ name and discuss the contribution of greenhouse gases to global warming
∑ explain the effects of global warming
∑ describe the remedial measures of greenhouse effect
∑ explain urbanisation, automobile pollution
∑ define acid rain and describe its causes and effects
∑ discuss the problems associated with ozone-layer depletion and its remedial
measures
∑ explain the causes of ozone-hole formation
∑ name and discuss the types of rainwater harvesting
∑ define rainwater harvesting
∑ describe the role of government and legal aspects in environmental
protection
∑ discuss the salient features of the
� Environment (Protection) Act, 1986
� Air (Prevention and Control of Pollution) Act, 1981
� Forest (Conservation) Act, 1980
� Wildlife Protection Act, 1972
� Water (Prevention and Control of Pollution) Act, 1984
∑ explain power of the state government to declare our pollution-control
areas and restrictions or use of certain industrial plants as given in air
prevention and control of pollution acts
∑ describe the Government Organisation/Department responsible for the
protection of the environment
∑ explain the role of NGOs and environment education in environmental
protection
∑ explain the meaning of industrial symbiosis, carbon credits, animal
husbandry and nuclear holocaust.
6.1 INTRODUCTION
The human population continues to increase, and with population growth comes
more requirements of food, shelter and clothing. Thus natural and managed
ecosystems are being exploited to provide increasing goods and services. Humans
may have reached the limit in some resources, and most of the ways we use the other
resources are presently unsustainable. In addition, humans extract and burn fossil
fuels much faster than they could ever be replen-
ished, bringing on change in global climate. Living iv
beings are forced to tolerate the continued loss of Conclusion
iii i
biodiversity. Rich persons are unwilling to take the Outcome Action
ii
necessary steps to help those suffering from pov- Effect
erty, hunger and illnesses.
6.1.1 Developing Countries

(i) Action Escalating human activities to meet survival needs of food, clothes,
shelter, etc.
(ii) Effect Resource depletion
(iii) Outcome Environmental degradation, poverty, ill-health, etc.
(iv) Conclusion The vicious cycle will continue with increasing human popula-
tion, hunger, malnutrition, lack of safe/clean water, sanitation problems, inadequate
shelter, etc.
6.1.2 Developed Countries

(i) Action Industrial revolution to meet desires of affluent persons
(ii) Effect Reliance on fossil fuels and nuclear power
(iii) Outcome Mass production and consumption, environmental pollution,
climate change, global warming, acid rain, ozone layer depletion, nuclear accidents,
etc.
(iv) Conclusion The vicious cycle will continue towards unsustainable society.
(a) Will it continue forever?
(b) Can you suggest some innovative way of economic development that would
improve the well-being and the sustainable well-being of the entire planet?
A summary of the current global and Indian crisis is presented below:
(i) Global Poverty (as per the World Bank, August 2008)
∑ 1.4 billion people live at or below poverty line of $ 1.25 a day.
(ii) State of the World’s Children (as per UNICEF, Feb. 2009)
∑ 2.5 billion people lack access to improved sanitation.
∑ 1 billion children are deprived of one or more services essential to survival
and development.
Social Issues and the Environment 6.3
∑ Over 24,000 children die every day around the world. This is equivalent
to 16–17 children dying every minute.
The silent killers are poverty, hunger, easily preventable diseases and illnesses.
(iii) Climate Change (as per NASA, October 2009)
For 6,50,000 years, atmospheric CO2 has never been above 300 parts per million. But
current levels are very high due to the Industrial Revolution. Increased greenhouse
gases and the greenhouse effect is expected to contribute to an overall warming of
the earth’s climate, leading to a global warming. 1900s was the warmest century
during the last 1000 years. Due to global warming, agricultural yield will decline
and biodiversity will be lost.
(iv) Scarcity (as per UNDP estimates, June 2009)
Due to climate change effects, an additional 600 million people will face food
shortages and malnourishment in the coming years, and 1.8 billion will struggle to
find water.
Many environmental problems arise from the abuse, misuse and overuse of
natural resources by humans. The world is heading for an environmental disaster,
and humans do not want to see, hear, or talk about it. If it continues, humanity will
no longer be able to co-exist with nature.
Development activities are necessary for humans in order to enhance the quality
of life and fulfill the needs of a fast-growing population. However, it should be
done in such a manner that natural resources are not exploited. Developments
must meet present needs without compromising the ability of future generations
to meet their own needs. Thus, it is essential to learn about the causes and effects
of current environmental issues of importance so that innovative solutions can be
implemented.
6.2 SUSTAINABLE DEVELOPMENT

Sustainable development means meeting the
needs of the present without compromising the
ability of future generations to meet their own
needs.
Sustainable development is a continuous
process. To be sustainable is a constant
challenge for humanity.
The pillars of sustainable development are
the following:
(i) Human and social capital, their cul-
ture and knowledge constitute social
pillar. Fig. 6.1 Pillars of Sustainable
(ii) Nature, biodiversity or natural capital Development (SD)
constitute environment pillar.
(iii) Money, goods or man-made capital constitute economic pillar.
(iv) The actions of governments to implement sustainable development in their

policies are considered the institutional pillar.
Social development, economic development and environmental protection are
equivalent objectives of sustainable development. These are illustrated in Fig. 6.2.
Sustainable development involves the simultaneous pursuit of economic
prosperity, environmental quality and social equity.
Fig. 6.2 Objectives of sustainable development
(A) Frameworks to Measure Sustainable Development (i) Agricul-

tural, industrial or other production and consumption activities are driving forces.
(ii) They impose stresses or pressures on the environment by releasing polluting sub-
stances.
Fig. 6.3 DPSIR framework: Driving force (D) – Pressure (P) –

State (S) – Impact (I) – Response (R)
(iii) These in turn, affect the state of the environment like global warming.
(iv) As a result, impacts (negative consequences on human health, economic loss in
production activities, floods, etc.) are caused or provoked. (v) For pollution preven-
tion, actions like sustainable use of resources are generated as responses.
(B) Environmental Sustainability When the sum total of nature’s

resources (natural capital) is used up faster than it can be replenished, degradation
of the environment occurs. However, if human activity only uses nature’s resources
at a rate at which they can be replenished naturally, sustainability occurs. These
situations are summarised below in Table 6.1.
Table 6.1 Environmental sustainability
Consumption of Renewable Resources State of Environment Sustainability
(i) Less than nature’s ability to replenish Environmental renewal Environmentally
sustainable
(ii) Equal to nature’s ability to replenish Environmental equilibrium Steady-state economy
(iii) More than nature’s ability to replenish Environmental degradation Not sustainable
(C) Major Obstacles in the Path of Sustainable Development in

India The major obstacles in the path of sustainable development are
(i) Population explosion
(ii) Absence of adequate political and industrial willingness for sustainable future
(iii) Non-availability of eco-friendly and resource efficient technology
(iv) Non-availability of sufficient funds
(v) Insufficiency of environmental awareness, non-conservation of resources
(vi) Absence of appropriate land-use planning
(vii) Absence of strict environmental laws and practices; absence of practice of
effective methods of pollution control
Fig. 6.4 Obstacles for sustainable development (India)
(D) Sustainable Lifestyle A lifestyle that attempts to reduce an individual’s

or society’s use of the earth’s natural resource and his/her own resources is known
as a sustainable lifestyle.
(E) Equitable Use of Resources for Sustainable Lifestyle Equitable

use of resources for sustainable lifestyle requires that the rate of use of renewable re-
sources do not exceed regeneration rates and rates of use of nonrenewable resources
do not exceed rates of development of renewal substitutes.
Some examples of lifestyle changes which we can adopt to assist in environmental
sustainable development are
(i) installing a rainwater harvesting tank,
(ii) washing our car on the lawn,
(iii) growing our own vegetables in the back garden,
(iv) using cloth bags for shopping and their re-use, instead of use of plastic bags
and discarding them in environment, and
(v) installing energy-saving light bulbs in our homes, schools, colleges, offices,
etc.
Case Studies
(i) Sustainable Development and Green Innovations
In today’s globalised world, an essential precondition is environmentally
sustainable industrial development, which can preserve the long-term interests
of communities who depend on the industry as well as societies whose livelihood
are affected by the operations of the industry. Societal expectations, competition
and the health of business environment influence decisions, actions and their
ultimate impact of businesses. The above aspects can be brought together in
the framework of responsible competitiveness that can help in achieving
environmental and social improvement, and economics of scale.
[Raja Rajeswari et al., Global Conference on Innovations in Management,
London, UK, 2011]
(ii) Constructed Wetland: A Cost-effective Alternative for Wastewater
Treatment
The city of Arcata, California, was faced with a dilemma in 1974: buy into an
expensive regional sewage processing plant to bring their wastewater discharge
into Homboidt Bay up to an acceptable quality or use some other alternative.
They used wastewater to create and nourish a wetland to provide prime wildlife
habitat and recreation for the community. Simultaneously, the wetland helped
in the purification of waste water.
[Amanda Suvtari http//www.ecotipping points.org]
(iii) Sustainable City

Portland is the 25th largest metropoli-
tan area in the US. Portland was expe-
riencing the typical problems of urban
growth, such as urban sprawl, traffic
congestion, and pressure on natural
areas within the city. The process in
which the spread of development across
the landscape far outpaces population
growth is termed sprawl. It is charac-
terised by four dimensions: (i) popu-
lation widely dispersed in low-density
development, (ii) widely separated
homes, stores, and workplaces, (iii) a Fig. 6.5 Determinants and advantages
network of roads marked by poor of urban liveability
connections and huge superblocks that concentrate traffic onto a few routes, and
(iv) absence of activity centres.
Now Portland provides an excellent example of intelligent urban planning.
They do so through an involving process of collaboration between citizens,
city officials, planners and other professionals to understand and work with
fundamental connections between transportation, economics, employment,
population and land use.
A movement in portland towards urban liveability consisted of
(a) orienting growth clustered along transportation corridors,
(b) creating various options for public transport,
(c) encouraging compact urban design, and
(d) proactively anticipating long-term growth.
They have been able to reduce pollution, traffic congestion, generate
employment, raise economy and build a sense of community.
[Amanda Suutari; http: //www.ecotipping points.org]
6.3 URBANISATION
From country to country, the definition of urban varies widely. Some countries
distinguish between urbal and rural based on
(i) Size or density of localities
(ii) Percentage of persons who are not dependent on agriculture
(iii) Administrative considerations (only major cities are classed as urban)
An urban area means a town or a city plus its adjacent suburbs with a population
of more than 2500 people. In contrast, a rural area means an area with less than
2500 people and less buildings.
Urban areas grow in two ways:
(i) Natural increase of its population by births
(ii) Immigration, mostly from rural areas [this is the biggest cause of urban
growth]
Urbanisation is defined as movement of people from rural to urban areas with
population growth equating to urban migration or it can also be defined as the physical
growth of urban areas as a result of global change.
Cities with populations greater than 10 million people are known as megacities.
For the first time in history, more than half of the world’s population is living in
towns and cities in 2008. This number will swell to almost 5 billion by 2030, with
urban growth concentrated in Asia and Africa.
6.3.1 Causes of Urbanisation

People move from rural areas to urban areas because cities offer more favourable
conditions for the resolution of environmental and social problems than rural areas.
A few specific reasons for urbanisation are summarised below:
(i) People move into cities to seek jobs and income.
(ii) With good governance, cities can deliver education, health care and other
services more efficienty than rural areas.
(iii) Cities provide opportunities for women’s empowerment and social

mobilisation.
(iv) Density of urban life relieves pressure on areas of biodiversity and natural
habitats.
(v) It is through cities that foreign money flows into a country (whether the
source is tourism or trade).
(vi) Restaurants, movie theaters, theme parks and other varieties of entertainment
are available in cities.
6.3.2 Drawbacks of Urbanisation

Often people who leave rural areas to find better jobs in the city have no choice
but to settle in slums, where they lack access to decent housing, drinking water,
sanitation, health care and education.
Fig. 6.6 Drawbacks of urbanisation
(i) Crimes Chances of robbery, murder, assault, CPU

etc., increases with unplanned urbanisation.
Crime Poverty Urban heat island
(ii) Poverty Poverty is growing faster in urban
Fig. 6.7 Consequences of
than in rural areas. One billion people live in
urbanisation
urban slums, which are typically overcrowded,
polluted and dangerous. Urban areas are not self-sustaining. They survive only by
importing food, water, energy, etc. However, they also produce large quantities of
waste.
(iii) Urban Heat Island As urban and industrial areas are developed, the majority
of the sun’s energy is absorbed by urban structures and asphalt. Thus, during warm
daylight hours, less evaporative cooling in

cities allows surface temperatures to rise
higher than in rural areas. Additional city
heat is given off by vehicles and factories as
well as by domestic and industrial cooling
and heating units. This effect causes the
city to become 1 to 6°C warmer than
surrounding landscapes. Impacts also
include intensification of carbon dioxide
emissions and reducing soil moisture. The
urban heat island has become a growing
concern and is increasing over the years.
Urbanisation is also responsible for
pollution (air, water, noise, etc.) and
traffic congestion.
6.3.3 Positive Environmental

Effects of Urbanisation
Some positive effects of urbanisation are
Fig. 6.8 Not self-sustaining urban city
the following:
(i) Prevention of overpopulation in future is possible because the birth rate of
new urban dwellers falls immediately to the replacement rate, and keeps
falling.
(ii) Spending per person on environmental protection is higher in urban areas.
(iii) Urbanisation puts a stop to slash and burn agriculture and other destructive
subsistence farming techniques.
(iv) Recycling is more feasible economically because of large concentration of
materials.
(v) It minimises land use by humans, leaving more for nature.
Fig. 6.9 Positive environment effects of urbanisation
6.4 WATER CONSERVATION

6.4.1 Rainwater Harvesting
Rainwater harvesting means collecting rainwater and storing/conserving it for a
later use.
(A) Various Methods of Rainwater Harvesting

There are two main methods of rainwater harvesting:
(i) Storage of Rainwater on the Surface for Future Use In this method,
traditional water-harvesting structures like artificial lakes, ponds, etc., are used as
such or after proper revival.
(ii) Recharge of Ground Water The structures used for recharge of ground
water are as follows:
(a) Hand Pumps The water should pass through a filter bed before percolation in
existing hand pumps. They are used for recharging aquifers.
(b) Pits They are 1–2 m wide and 3 m deep. They are also back filled with gravel
and coarse sand to aid filtration before percolation to the ground. They are used for
recharging a shallow aquifer.
(c) Dug Wells The rain water, after filtration, is put into existing dug wells for
storage.
(d) Roof-Top and Road-Rop Collection of Rainwater In urban areas, these
methods are very useful to recharge aquifers.
Cloud
Rain water
Roof-top
Hand
pump Ground
(b)
(a) Dug well
Water table
Fig. 6.10 Roof-top rainwater harvesting by recharging (a) through hand pump,
or (b) through an abandoned dug well
Case Studies
(i) Rainwater Harvesting to Replenish Underground Water (Rajasthan,
India)
As a consequence of logging the forest, the wells in Rajasthan’s Alwar District
had dried up, thrusting the people into hopeless and unavoidable poverty. The
revival of johad (a crescent half-moon shapped dam of earth and rocks) to capture
rainwater for recharging the underground water supply provided a turning point
that brought the wells back to life. And with the water came a better life for the
people. It started in the Gopalpura village. Now, nearly a thousand villages are
following this practice.
More vegetation More More
underground water
water in wells
Less erosion More johad More motivation

less sediment in johads capacity to stay in
less labor required to village
maintain johad
Restoring johad Men return to village; More, water for

and traditional more labor to irrigation,
village council maintain johad more agriculture
work in village
Fig. 6.11 Rainwater harvesting in Rajasthan

[http: //www.ipptaonline.org/circular]
(ii) Water Conservation in India in the Pulp and Paper Industry

The annual paper production will be double from the existing 10–11 million
tones by 2020. However, the availability of water will be the same or lower.
Thus, for sustainable development, it is essential to work towards stringent water
management. The available options are use, reuse, recycle, treatment of waste
water, reduction of consumption of fresh water, etc.
6.4.2 Watershed Management

Watershed is a geographic area of land that collects, stores, and releases water.
The area collects water from rain, snow, etc. This collected water is stored in lakes
and ponds. The stored water is then released through streams, rivers, etc. Thus, a
watershed means a land from where water drains into a particular stream, lake, river,
estuary and even the ocean. Drainage basin or catchment basins are other terms used
interchangeably with watershed.
A watershed is a natural system. All lands, humans, wildlife and their activities
are part of one or the other watershed. When a watershed is kept in good condition,
it provides sustainable benefits to humans, wildlife, etc.
Watershed management refers to the conservation, protection and restoration of a
watershed to secure water—both in quantity and quality for drinking, sanitation and
agriculture in a sustained manner.
(A) Strategies for Watershed Management: CUBS
C: Cost-benefit (i) Do the cost-benefit analysis of ecological effects of alternative
actions.
U: Usage goals (ii) Develop goals for use of water and land resources.
B: Background of people and functions of watershed (iii) Find out present and
historical structure and functions of the watershed system among people of
diverse social backgrounds and values.
S: Solutions for sustainability (iv) Suggest innovative cost-effective solutions of
optimum resource use for long-term sustainability of the watershed and the
ecosystem.
Fig. 6.12 Watershed and its management
(B) Action Plan for Watershed Management Watershed management

can be done through MCD:
(i) Mapping of the watershed area, planting trees and grass for enhancing seeping
of water to the ground and for preventing water contamination, torrents and
landslides. Thus, plantation helps in the recharging of groundwater.
(ii) Constructing a series of long trenches and mounds along hill contours to
hold rainwater and allowing it to percolate into the ground.
(iii) Making dams for preventing large amounts of water from rushing down
the hillside. This helps in recharging of an underground aquifer. Moreover,
streams and rivers flow for the whole year.
(C) Need of Watershed Management: MUD

M: Misuse (i) The misuse of Himalayan slopes are increasing. Our water regimes
are threatened resulting in the depletion of water resources.
U: Unsustainable (ii) The society is becoming unsustainable.
D: Damage (iii) The damage to irrigation systems and reservoirs are increasing.
Every year, during the ‘rainy season’, costs for controlling floods is increasing.
(D) Advantages of Watershed Management
The main benefits of watershed management are summarised below:
(i) Watershed management reduces water shortage during summers by
facilitating recharge of groundwater.
(ii) It provides wildlife and fish, food, habitat, and resting areas, etc., for
sustainable survival.
(iii) It protects stream and river banks from erosion.
(iv) By retaining water and releasing it during summers, watershed management
reduces chances and associated damages of floods.
(v) It provides good quality water and food for human use.
6.5 RESETTLEMENT AND REHABILITATION OF

PEOPLE; ITS PROBLEMS AND CONCERNS
The displacement or the involuntary and forced relocation of people is the most
significant negative impact of many development projects such as power plants, oil
refineries, fertiliser and chemical industries, river-valley projects, dams, reservoirs
and mining.
This involuntary movement of people from one place to another, for resettlement,
gives rise to the following problems:
(A) Economical Problems
(i) Compensation is awarded only to real owners of property taken for
developmental projects. Tenants, wage labourers, artisans and encroachers
are not considered eligible for compensation but ironically they are the most
vulnerable and in need of support.
(ii) Families are forced to face long-term hardships.
(iii) Under the acquisition process, community assets and common resources
like grazing grounds and forests are not compensated. But these areas were
critical for the livelihood of the poorest.
(iv) Sources of income are lost or ruined or jeopardised,
(v) The resettlement cost is generally underestimated and under-financed.
Whenever the development project runs into financial problems, mostly the
resettlement and rehabilitation budget is reduced.
(vi) Most programmes have failed to facilitate self-employment in critical areas
of employment, skills and capacity building.
Fig. 6.13 Economical problems of resettlement and rehabilitation
(B) Social Problems

(i) Social networks are disturbed.
(ii) Large families and communities are broken up and resettled over a wide area.
(iii) Poor people are transplanted from a social ecology in which they were
primary actors to one in which they are aliens. Such people are very vulnerable
and forced to become underclass members of a new socio-cultural milieu.
Traditions are weakened. Cultural identity is lost.
(iv) Generally, participation of the victims has been superficial or treated as
unimportant by those responsible for the development project.
Fig. 6.14 Social problems of resettlement and rehabilitation
(C) Educational, Psychological and Environmental Problems

(i) Effective resettlement is never ensured nor implemented because of
institutional weaknesses, confusions between various departments, absence
of policy, absence of legal instruments and absence of an effective mechanism
to monitor compliance. All these result in
(a) Interruption of education of children
(b) Separation of joint families resulting in psychological tensions among
members of the family
(c) Unemployment, debt bondage, hunger and assetlessness
(ii) Resettlement sites are not selected with respect to availability of livelihood
opportunities. Even proper residential houses are not provided. The People
are forced to live in small, temporary structures made of tin or other
inappropriate material and design. Basic amenities and essential infrastructure
such as health, schooling and credit are not available in these resettlement
sites.
(iii) Planning time for most of the projects is long. There is a huge time gap
between initial notifications and the actual physical relocation. The interim
period is full of uncertainties and enormous psycho-social anxieties for the
to-be-relocated communities. People in such areas thus become poorer even
before they are relocated for settlement.
(D) Rehabilitation and Resettlement Concerns

Rehabilitation should be envisioned as a process that would reverse the risks of
resettlement.
The objective of the Ministry of Rehabilitation and Resettlement (Government
of India) is to transfer the benefits, in lieu of the losses occurred to displaced people
due to involuntarily displacement.
This objective may be ensured by implementing the following policies:
(i) To keep them intact in a family or community in which they were settled
prior to being displaced
(ii) To provide them essential infrastructure such as health, schooling and credit
in resettlement sites
(iii) To govern the displacement process by laws for avoiding possible problems,
to create new rights for them that will enable them to directly share the
benefits of the development project and to provide adequate compensation
(iv) To relocate them to a locality of their preference
(v) To provide them increasing incomes through opportunities of employment
and livelihood, to provide them opportunities for the enhancement of
capabilities and to improve their standard of living
(vi) To give them proper participation and choice for their resettlement and
rehabilitation
(vii) To provide them social infrastructure and community services
Fig. 6.15 Policies to ensure fulfillment of objectives of

rehabilitation and resettlement
6.5.1 Environmental Ethics: Issues and Possible Solutions

The work ‘ethic’ is derived from the Greek work ‘ethos’ which means the character
of a person as described by his or her actions.
Ethics deals with moral duty and obligations. It gives rise to a set of values, which
are used to judge whether one’s behaviour or conduct is right or wrong.
Trust, honesty, justice, trustworthiness, competence and accountability are the
basis of ethics.
(A) Issues In early 1970s, the world started realising the dangers of human ac-
tions on the environment. The main reasons of such concerns were the following
issues whose effects were changing the global environment: “ACNE”
A (i) Reduced purification of atmosphere because of increased deforestation
C (ii) Increased CO2 concentration and presence of harmful elements in
atmosphere due to enhanced burning of fossil fuels
N (iii) Depletion of natural resources at a rapid rate due to consumption by

increasing population
E (iv) Deteriorating quality of environment because of urbanisation,
industrialisation, deforestation, consumerism, etc.
These issues result in the following serious consequences:
Greenhouse effect, global warming, acid rain, ozone layer depletion, etc.
(B) Possible Solutions Awareness of consequences like global warming, etc.,
has led the society to adopt environmental ethics. These environmental ethics give
equal importance to growth and sustainability.
The Following ethical guidelines are very useful as possible solutions for most
environment-related problems:
(i) Humans must keep themselves informed about ecological changes as a result
of development.
(ii) Humans must understand that they cannot survive alone on the earth. The
earth is the habitat of all living species. Living species depend on each other
for survival.
(iii) All humans must be cooperative, honest, affectionate and polite to nature
and society.
(iv) Humans must respect nature. They are part of it.
(v) Humans should act locally for protection of environment globally.
(vi) Humans must protect natural resources and energies as resources are depleting
fast.
(vii) Humans must reserve scarce resources for the future and the future
generations.
(viii) Humans must involve themselves in the care of the earth.
(ix) Everyone should try to bring about a change in the attitudes of other
persons. They should collectively work towards conservation, protection and
restoration of the environment.
(x) Each human should plant at least one tree on his or her birthday.
(xi) Humans should purchase only that much which is essential because excess
turns into wastage.
Case Study
Resettling Project-Affected People in India
A concern for the fate of people who are forced to relocate, leaving behind forever
their homes, land and communities is a contemporary issue of great importance.
A variety of irrigation, hydropower, mining, and thermal-power projects are
responsible for resettlement. The affected people face risks like insecurity of
livelihood; problems of access to common property and public services; health
and nutrition hazards; loss of community structures and social unrest, etc. The
simple solution is proactive planning so that corrective measures can be taken.
[http: //www.usp.ac.fj]
6.6 SOCIAL ISSUES AND THE ENVIRONMENT
6.6.1 Climate Change

Weather is the reflection of atmospheric humidity, temperature and rainfall.
Climate is the average weather pattern over longer duration in a place.
Climate change is reflected from the following facts:
(i) Since the late 19th century, the earth has warmed by 0.3 to 0.6°C on an
average.
(ii) By the year 2100,
(a) Temperatures would rise by 1 to 3.5°C
(b) Global mean sea levels would rise by 15 to 95 cm
Causes of climate change on a global scale are linked with changes in the amount
of heat that is either let into the earth system or let out of the earth system.
Depending on proximity to oceans and altitude and amounts of sunlight received
by different regions of the world, climate differs from place to place.
For example, hot climates are due to greater concentrations of greenhouse gases
in the atmosphere which reduce
the amount of heat that is let out
of the atmosphere.
Ill-effects of climate change are
linked to
(i) cyclones,
(ii) floods,
(iii) dry or wet spells of rainfall,
and
(iv) cold and hot spells of tem-
perature. Fig. 6.16 Impacts of climate change
Table 6.2 Ill-effects of climate change

Phenomenon Probability Likelihood
(i) More extreme sea levels >66% Likely
(ii) More intense tropical cyclones ¢¢ ¢¢
(iii) More area hit by drought ¢¢ ¢¢
(iv) More heavy rain events >90% Very likely
(v) More warm spells and heat waves ¢¢ ¢¢
(vi) Warmer days/nights >99% Virtually certain
(A) Impacts of Climate Change

(i) Positive Impacts Reduced deaths from cold and higher agricultural output in
northern regions (at least for a while) are few positive impacts of global warming.
(ii) Negative Impacts

(a) Submergence of low-lying islands (especially in the Pacific), vast saline
inundations in countries like Bangladesh, etc., are linked to rise in sea level.
(Global warming is responsible for melting of ice caps and glaciers, which
lead to rise in sea level.)
(b) The tourism industry will suffer in parts of southern Europe because
of change of climate towards hotter than ever before (prediction by the
European Acacia Project).
(c) Damaging changes in wildlife behaviour like failure of Scottish seabirds to
raise young during the 2004 breeding season.
(d) The poorest of the poor are most likely to be hit by the impacts of climate
change.
(B) Solutions of Climate-change Problems Some of the simple solutions
are
(i) Reduce the emission of greenhouse gases
(ii) Use renewable energy resources
(iii) Use energy efficient technologies
example 1 What are the important mitigation technologies and commer-

cially available latest technologies for tackling the climate change as per Fourth
Assessment Report of Intergovernmental Panel on Climate Change (IPCC)?
Solution As per the IPCC Fourth Assessment Report, the important mitigation
technologies and practices presently commercially available are described below:
(i) Industry
∑ Recovery of heat and power
∑ Recycling of material
∑ Green technology
∑ Efficient equipment, etc.
(ii) Buildings
∑ Passive and active solar design for cooling and heating
∑ Efficient electrical appliances
∑ Improved cooking stoves
∑ Efficient lighting and day lighting, etc.
(iii) Transport
∑ Use of public transport systems
∑ Cycling, walking, etc., nonmotorised transport
∑ Use of best fuel-efficient vehicles
∑ Biofuels
∑ Proper transport planning, etc.
(iv) Energy supply
∑ Renewable energy
∑ Improved efficiency in supply and distribution, etc.
(v) Agriculture
∑ Improved nitrogen fertiliser-application techniques to reduce N2O
emissions,
∑ Improved rice-cultivation techniques and livestock-and-manure man-
agement to reduce CH4 emissions,
∑ Dedicated energy corps to replace fossil-fuel use,
∑ Improved crop and grazing-land management, etc., to increase soil
carbon storage,
(vi) Waste
∑ Recycling and waste minimisation
∑ Compositing of organic waste
∑ Waste incineration with energy recovery
∑ Waste-water treatment, etc.
∑ Landfill methane recovery
(vii) Forests
∑ Reduced deforestation
∑ Forest management
∑ Afforestation
∑ Reforestation
∑ Harvested wood-product management
∑ Use of forestry products for bio-energy to replace use of fossil fuel, etc.
Case Study
Climate Change, Perspectives from India
Climate change is the biggest development challenge for the planet. There is not
much difference between managing a local forest and the global climate—we
need a framework which encourages cooperation. Then a country can have both
growth and less carbon emissions. To tackle the impact of climate change on food
security in India, it has been suggested to practice soil and water conservation.
Small-scale industries emit substantial greenhouse gases and have the potential
for saving huge amounts of energy.
[http: //www.undp.org.in]
(C) Environment Security and Climate Change
The security of the entire global community is increasingly exposed to risk by humans
through air, water and/or land pollution. Economic activities cause environmental
changes that lead to conflict. This can be understood through the illustration shown
in Fig. 6.17.
It is important for all countries to cooperate in order to reduce the effects of
environmental degradation. Everyone should contribute by limiting greenhouse gas
emission, conserving natural resources, and developing and sharing energy-efficient
technologies.
[Elizabeth b. Chaleck;, http: //www.pacinst.org/reporst]
Fig. 6.17 Origin of conflict and methods to reduce them
6.6.2 Global Warming—The Greenhouse Effect

Greenhouse effect is a process by which infrared radiation leaving the earth’s surface is
trapped by some greenhouse gases; so the temperature is higher than it would be if direct
heating by solar radiation were the only warming mechanism.
Greenhouse effect is illustrated in Fig. 6.18.
1. Incoming solar radiation [short wave:

(0.2–4) nm]
2. Reflected solar radiation
3. Net incoming solar radiation
4. Absorbed solar radiation
5. Energy trapped by greenhouse gases
6. Outgoing infrared radiation [long
wave: (4–100) nm]
Fig. 6.18 Greenhouse effect
1. Short-wave radiations from the sun penetrate the earth’s atmosphere.

2. Some solar radiation is reflected by the atmosphere and the earth’s surface.
3. Remaining solar radiation reaches the earth’s surface.
4. Solar energy is absorbed by the earth’s surface and warms it and is converted
into heat causing the emission of long-wave (infrared) radiation back to the
atmosphere.
5. Some of the infrared radiation is absorbed and re-emitted by the greenhouse
gases. The direct effect is the warming of the earth’s surface and the tropo-
sphere. The earth’s surface gains more heat and infrared radiation is emitted
again. By this process, some of the infrared radiation is trapped in the atmo-
sphere by greenhouse gases causing a warming of the earth’s climate.
6. Some of the infrared radiation passes through the atmosphere and is lost in
space.
To sum up, the greenhouse effect is the rise in temperature that the earth
experiences because certain gases in the atmosphere trap energy from the sun.
∑ Concentration of greenhouse gases: Normal Excessive

∑ Surface temperature of earth: £14°C (14.1 to 14.5)°C
Greenhouse gases are gases in an atmosphere that absorb and emit radiation
within the thermal infrared range.
Examples: Carbon dioxide, nitrous oxide, methane, water vapour, ozone
Greenhouse gases greatly affect the temperature of the earth. Without them, the
earth’s surface would be (on average) about 33°C colder than at present, and life
would be impossible.
(A) Contribution of Greenhouse Gases to Global Warming Green-
house gases vary in their ability to absorb and hold heat in the atmosphere. For
example, nitrous oxide absorbs 270 times more heat per molecule than carbon diox-
ide, and methane absorbs 21 times more heat per molecule than carbon dioxide.
The Global Warming Potential (GWP) depends on both the efficiency of the
molecule as a greenhouse gas and its atmospheric lifetime. GWP is measured relative
to the same mass of CO2 and evaluated for a specific time scale. For example, if a
greenhouse gas has a high GWP on a short time scale (say 20 years) but has only
a short lifetime, it will have a large GWP on a 20-year scale but a less GWP on a
bigger time scale. If a molecule has a longer atmospheric lifetime than CO2, its
GWP will increase with the increase in the time scale.
Table 6.3 Global Warming Potential (GWP)
Greenhouse Gas Atmospheric Life- Global Warming Potential (GWP)
time (years) 20 years 100 years 500 years
(i) CO2 104 1 1 1
(ii) CH4 12 ± 3 72 25 7.6
(iii) N2O 114 289 298 153
(iv) CFC–12 100 11000 10900 5200
(v) HCFC–22 12 5160 1810 549
(vi) SF6 3200 16300 22800 32600
(vii) NF3 740 12300 17200 20700
(B) Global Warming

Global warming means a rise in temperature over the earth’s surface.
It is primarily caused by CO2 emission by man-made activities.
Fig. 6.19 Impact of global warming and greenhouse effect
(i) Consequences of Global Warming

(a) Melting of polar ice caps, and increase of sea/ocean levels
(b) Flooding of low-lying land
(c) Less water vapour in the atmosphere leading to more drought
(d) Causes extremes of weather hurricanes, flooding and droughts, difficulties in
growing crops and survival problems
More industrialised countries are responsible for causing high levels of CO2 in
the atmosphere and less industrialised countries are also contributing by destruction
of the rainforest.
Sustainable development is the only solution,
[http: //www.thw.coventry.sch.uk/]
(ii) Remedial Measures
(a) Enhance energy efficiency during use by adding insulation to your walls, and
by using CFL bulbs, etc.
(b) Reduce transport sector emissions by less and smart driving.
(c) Promote renewable energy (like solar energy) usage.
(d) Remove subsidies on fossil fuels.
(e) Favour sustainable agriculture.
(f) Recover methane emissions through waste management.
(g) Promote afforestation and reforestations—a single tree will absorb approxi-
mately one ton of CO2 during its lifetime.
(h) Reduce energy consumption by using energy-efficient home appliances.
(i) Avoid methane production from biomass decay through controlled
combustion.
(j) Enhance energy efficiency during generation, transmission and distribution.
(k) Reduce waste, prefer reusable products, recycle paper, plastic, metals, etc.
(l) Eat locally grown fruits and vegetables and not the imported ones. The latter
requires the burning of fossil fuels for transport.
6.6.3 Acid Rain

Acid rain is rain which is unusually acidic (pH of less than the natural range of 5 to 6);
caused mainly by atmospheric pollution with sulphur dioxide and nitrogen compounds.
Table 6.4 Environmental effects of acid rain

pH Value Examples Environmental Effects
4.2–4.4 Acid rain All fishes die at pH = 4.2
4.5 Acidic lake Frog eggs, tadpoles, cray fish die at pH = 4.5
5.6 Clean rain
6.5 Healthy lake
6.5–6.8 Milk
7 Pure water
8 Sea water
Notes: pH = – logarithm [hydrogen-ion concentration]
As the pH is log [H+], so each pH unit represents a tenfold change:
(i) A pH of 5 is ten times more acidic than a pH of 6.
(ii) A pH of 4 is hundred times more acidic than a pH of 6.
rainwater
Fig. 6.20 Causes and effects of acid rain
Case Study
Acid Rain and Taj Mahal
Tourist traffic is not allowed near the Taj Mahal in an effort to control the
deleterious effects of pollution. The degradation of the Taj Mahal’s marble
facades has still not slowed down. This is due to acid rain generated from local
foundries and an oil refinery. The once brilliant white Taj Mahal has been losing
its luster, dulling into a sickly pale shade. Two common air pollutants, SO2 and
NOX, cause acid rain.
[John mink, http: //archive.cyark.org]
6.6.4 Ozone-Layer Depletion (Ozone Hole)

(A) Ozone Ozone (O3) is an allotropic form of oxygen (O2). It is a pale blue
gas. It helps in sustaining life on earth by filtering out the sun’s harmful ultraviolet
radiation.
(B) Ozone Layer The total amount of ozone in an overhead column of the
atmosphere is measured in dobson unit (after the atmospheric ozone pioneer GMB
Dobson). One Dobson Unit (DU) indicates that a 0.01 mm thick ozone layer would
be formed if ozone is compressed into one layer at 0°C and 1 atm pressure. Across
the globe, in the stratosphere, the average thickness of the ozone layer is about 3 mm
at 0°C and 1 atm pressure (or about 300 DU). The stratospheric pool of ozone is
known as the ozonosphere.
(C) Ozone Hole When the level of ozone in the stratosphere falls below
200 DU, it is considered to represent the beginnings of an ozone hole.
(D) Causes of Ozone-Hole Formation The gradual thinning of the ozone
layer and ozone-hole formation occurs by the destruction of ozone due to its reac-
tions with nitric oxide, chlorine, hydroxyl radicals, etc., in the stratosphere.
Flying of supersonic aircrafts, nuclear explosions and various chemical/
photochemical reactions in the atmosphere generate nitric oxide. Burning of biomass
generates hydroxyl radicals. Volcanic activity releases chlorine in the atmosphere.
Chlorofluorocarbons (CFCs), fluorochloro methane (freons), difluorodichloro
methane (CF2Cl2) and fluorochloroform (CFCl3) release chlorine by ultraviolet
radiation induced homolytic cleavage in the atmosphere.
It is estimated that about 6.5% of the total ozone-layer depletion is due to chlorine
radicals from various CFCs. The chemical reactions leading to the destruction of
ozone layer by CFCs are given below:
Step (a): CCl2F2 + hn Æ Cl + CClF2
Step (b): O3 + Cl Æ O2 + ClO
Step (c): ClO + O Æ Cl + O2
Cl
Net reaction: O3 + O ææÆ 2O2
As Cl atoms are regenerated in step (c), a long-chain process is followed which
keeps on consuming ozone. It is estimated that each atom of chlorine can destroy
one lakh ozone molecules when they diffuse to the stratospheric level.
Fig. 6.21 Ozone depletion process

(E) Problems Associated with Ozone-Layer Depletion The ozone

layer absorbs most of the harmful ultraviolet radiations coming from the sun in the
region (220–330) nm.
In the absence of an ozone layer, these ultraviolet radiations could cause the
following problems:
(i) Swelling of skin and skin cancer; skin aging, burning sensation
(ii) Death of phytoplanktons in marine environment (the sole producers) leading
the entire ecosystem to collapse
(iii) Reduction in the body’s ability to fight off disease, as UV suppresses the
immune system; premature aging.
(iv) Inhibition and alteration of DNA replication and formation of DNA adduct;
leukamia, breast cancer
(v) Visual impairment, dizziness, cataracts of eyes
(vi) Damage to plants; reduction in crop yields; faster deterioration of paints,
fabrics, plastics
Fig. 6.22 Problems associated with ozone-layer depletion
(F) Remedial Measures to Control the Depletion of Ozone Layer

(i) Avoid any fire extinguisher that contains bromine-based halons. Preferably
use water, carbon dioxide or dry chemical fire extinguishers.
(ii) Spread awareness about the restricted use of CFCs for the healthy survival of
mankind.
(iii) Avoid purchasing and using refrigerators, air conditioners, etc., which use
CFCs, freons, etc., as coolants.
(iv) Avoid purchasing and using pressurised aerosol cans which use CFCs, freons,
etc., as propellants.
(v) Ban atmospheric nuclear explosions, as they emit NO and deplete the ozone
layer.
(vi) Reduce the air traffic of supersonic aircrafts that fly at the ozonosphere
altitude, as they release large amounts of NO and deplete the ozone layer.
(vii) Facilitate advanced research to plug the ozone holes that have already been
formed.
Case Study
Ozone-Layer Depletion
Concern over the annual ozone hole over Antarctica led the Reagan administration
to agree to the Montreal Protocol (1987). This was the landmark international
agreement to phase out chlorofluorocarbons (CFCs) and other ozone-depleting

compounds.
It has been recently demonstrated (2010) that the ozone hole is able to influence
the tropical circulation and increase rainfall at low latitudes in the southern
hemisphere. Thus, the ozone hole is a big player in the climate system.
This means that international agreements about reducing climate change
should concern stopping ozone-layer depletion along with reducing CO2
emissions.
[Anthony Watts, April 2011, http: //wattsupwiththat.com/2011]
6.6.5 Nuclear Accidents and Holocaust

(A) Nuclear Accidents
Nuclear accidents can occur at any stage of the nuclear fuel cycle. They may also
result from the failure of nuclear devices.
Types of nuclear accidents are discussed below:
(i) Lost-Source Accidents In such accidents, a radioactive source is lost, stolen
or abandoned. The source then might cause harm to the environment or humans.
(ii) Human-Error-Based Accidents Humans have made errors while
(a) Calculating the activity of a teletherapy source for radiotherapy
(b) Attempting to service nuclear equipment and plants
(c) Performing nuclear experiments.
For instance, in 1946, Canadian Manhattan Project physicist Louis Slotin was
performing “tickling the dragon’s tail” experiment. This experiment involved
two hemispheres of plutonium being brought together until separated only by
a screwdriver. One day, the screwdriver slipped unfortunately. The plutonium
hemispheres then touched and set off a chain reaction criticality accident. The lab
was filled with harmful radiation and a flash of blue light. To stop the chain reaction,
Louis Slotin bravely pushed the hemispheres apart with his bare hands. His efforts
saved the life of several other co-workers present in the room. Unfortunately, Louis
Slotin died within 10 days because his body absorbed a lethal dose of radiation.
(iii) Equipment Failure Type of Accidents A simple initial failure of a
semiconductor diode followed by an equipment failure can result in malfunction
of a particle accelerator, resulting in the overexposure of a patient undergoing
treatment for cancer.
(iv) Transport Accidents A defective gamma radiography set was transported
as cargo in a passenger bus in Cochabamba. The gamma source was outside the
shielding, and it irradiated some bus passengers.
A court case had revealed that a radiotherapy source with defective shielding was
transported from Leeds to Sellafield in the United Kingdom. On the underside,
the shielding had a gap from which radiation was escaping and harming the
passengers.
(v) Decay Heat Accidents The heat generated by the radioactive decay in a
nuclear reactor (without a coolant) can result in a accident causing partial melting
of the core and damaging the nuclear fuel.
(vi) Criticality Accidents Criticality accidents are smaller scale accidents in
which
(a) only a few people can be harmed,
(b) no or small release of radioactivity occurs outside the experimental hall,
(c) limited off-site release of gamma and neutron radiation occurs, and
(d) the system remains critical for longer durations (even few days) before it
could be stopped.
(B) World’s Major Nuclear Accidents
(i) Three Mile Island Accident On March 28, 1979, a nuclear accident
occurred in US at the Three Mile Island nuclear power plant. One of two reactors
lost its coolant, which caused overheating and partial meltdown of its uranium core.
This resulted in release of intense radiation as well as radioisotopes. Fortunately, the
plume emitted into the atmosphere was quite low for causing toxic effect.
(ii) Chernobyl Nuclear Accident On April 26, 1986, a nuclear accident
occurred in Chernobyl, near Kiev, Ukraine. Explosion and fire in the graphite core
of one of four reactors released radioactive material that spread over part of the Soviet
Union, eastern Europe, western Europe and Scandinavia. This is one of the world’s
worst nuclear accidents involving 237 confirmed cases of chronic radiation illness
and 37 deaths. Hundreds of thousands of Ukrainians, Russians and Belorussians had
to abandon entire cities within a 30 km zone of extreme contamination. About 3
million people, more that 2 million in Belarus alone are still living in contaminated
areas. Figures from the Ukraine Radiological Institute suggest that over 2500 deaths
were caused by the Chernobyl nuclear disaster.
(iii) Tokaimura Nuclear Accident On September 30, 1999, a nuclear accident
occurred in a nuclear plant in Tokaimura, Japan. In a uranium-processing nuclear
fuel plant, a chain reaction went uncontrolled, resulting in emission of high levels
of radioactive gas into the air. Because of this accident, two workers were seriously
injured and one worker got killed.
Populations living in contaminated areas and persons who helped with the clean-
up of the accident were found to have thyroid or other cancers. Among Ukrainian
young children (up to 15 years of age), the average thyroid cancer rate was 4–6
incidents per million before the accident. After the incident, the cancer rate rose to
45 incidents per million.
People were not told the truth until several years after the accident. The lack of
public information available after the accident, the stress and trauma of evacuation
and concerns of the people affected and concerns about their children’s health
resulted in significant increases in psychological health disorders such as depression,
anxiety, helplessness, social withdrawal, mental stress and lack of hope for the
future.
(C) Nuclear Holocaust

Holocaust means large-scale destruction of human lives by intense heat and fire.
Holocaust: Great Destruction Resulting in the Extensive Loss of Life
Hiroshima–Nagasaki disaster is a nuclear holocaust. America was involved in the
development of an atom bomb while World War II was at its peak. The bomb was
made and was test fired on 16 July, 1945 in a desert in Mexico. The 30 m tower on
which the bomb was placed completely melted. The blinding light that spread for a
few minutes turned the sun into a pale ball. Frightened to the core by the resulting
blast, scientists vehemently opposed using it on Japan or anywhere in the world.
US President Harry Truman was determined to win the war against Japan. He
ordered dropping of the bomb on Japan. The uranium bomb named the Little Boy
was dropped on Hiroshima on August 6, 1945. Within minutes, one lakh persons
were burnt to death like moths near a lamp. Just three days later, a plutonium bomb
named Fatman was dropped over Nagasaki. The whole area was burnt and looked
like a desert. Devastating shock waves, deadly gamma radiations and enormous
amount of heat created conditions where any life cannot survive.
It is estimated that by December 1945, as many as 1,40,000 had died in Hiroshima
by the uranium bomb and its associated effects. In Nagasaki, roughly 74,000 people
died of the plutonium bomb and its after effects. In both cities, around 2,14,000
people in total, most of them were civilians, were killed. In Nagasaki alone, up to
60,000 people were injured. The radius of total destruction was about 1.6 km,
followed by fire across the northern portion of the city to 3.2 km south of the
bomb.
Table 6.5 Classification of accidents according to the International Nuclear and
Radiological Events Scale (INES)
Accident Description Example
1. Anomaly At a nuclear facility any break of pre- —
scribed operating limits
2. Incident Spread of contamination to an area of the Cadarache, France
facility which is not expected by design (1993)
3. Series incident Release of large quantity of radioactive Sellafield, Britain
material, contained with the installation (2005)
4. Accident with local At a nuclear facility, fatal overexposure of Tokaimura, Japan
consequences workers after a criticality event (1999)
5. Accident with wider Severe damage to reactor core Three Mile Island,
consequences US (1979)
6. Serious accident Explosion of waste tank and significant Kyshtyn, Russia
release of radioactive material (1957)
7. Major Accident External release of significant fraction Chernobyl, Ukraine
of core, widespread environmental and (1986)
health effects
Radiation poisoning and necrosis caused illness and death after the bombing in
about 1% of Hiroshima residents who survived the initial explosion. In the years
between 1950 and 1990, It is estimated that hundreds of deaths are attributable
to radiation exposure among atomic-bomb survivors from both Hiroshima and
Nagasaki.
6.7 WASTELAND RECLAMATION

Land is a precious resource because it is used for agriculture, pastures and grazing
fields, housing, agroforestry, roads, industrial areas, forestry, etc.
Wasteland is a land which is
(i) abandoned,
(ii) degraded and thus ecologically unstable,
(iii) incapable of producing material or service of value,
(iv) eroded,
(v) unfit for cultivation, unproductive, unfit for grazing as greenery cannot be
sustained, and
(vi) saline, waterlogged, not being utilised to its potentials.
Fig. 6.23 Wasteland attributes
Fig. 6.24 Wasteland examples
Fig. 6.25 Causes of formation of wastelands

(A) Classification of Wastelands

Wasteland is broadly classified into the following two types:
(i) Cultivable Wastelands The lands are cultivable but not cultivated for more
than five years due to various reasons such as being declared as notified forest area
or state or private occupation.
Examples: Waterlogged marshy lands, saline lands, degraded forests, degraded pas-
tures (or degraded grasslands), shifting cultivation land, gullied land, strip land, etc.
(ii) Uncultivable or Barren Wastelands
These wastelands cannot be brought under cultivation or economic use except at a
very high cost.
Examples: Barren rocky lands, areas covered by snow or glaciers, steep sloping areas.
(B) Drawbacks of Wastelands Formation Formation of wastelands result
in the deterioration of ecological balance. The various components of the ecosystem
directly or indirectly dependent on that particular wasteland are adversely affected.
(C) Wasteland Reclamation

Wasteland reclamation is the process of converting sterile, barren wasteland into
something that is fertile and suitable for habitation and cultivation.
(D) Wasteland-Reclamation Practices
Some of the important wasteland-reclamation practices are briefly described below:
(i) Changing Agricultural Practices Jhoom or shifting cultivation should be
replaced by crop rotation, mixed cropping or developing plantation crops which
would improve fertility of land and support a large population.
(a) Mulching It means providing protective cover to stop the shifting of sand. A
mulch is a protective layer formed by the stubble, i.e., the basal parts of herbaceous
plants, especially cereals, attached to the soil after harvest. Dry stems of maize,
tobacco, and cotton are used as multch. For mulching, artificial protective covering
can also be used. Mulches act as wind barriers; so soil erosion due to wind is
reduced. By addition of organic matter, mulches reduce evaporation and increase
soil moisture. Even mulching is useful against water erosion.
(b) Managing Topography Water running down the hill erodes soil. The faster it
runs, the more soil it carries off the fields. Soil erosion and wasteland formation can
be minimised by the following methods:
∑ Strip Farming In alternating strips along the contours, different kinds of
crops are planted. When one crop is harvested, the other is still present to
protect the soil and keep water from running straight downhill.
∑ Contour Ploughing The ploughing of land is done across the hill, and
not in up and down style as in contour ploughing, The ridges created by
cultivation make little dams that trap water and allow it to seep into the soil
rather than running off.
∑ Tied Ridges This method involves a series of ridges running at right angles
to each other, so that water run-off is blocked in every direction and is
encouraged to soak into the soil. Tied ridges are very useful in very heavy
rainfall areas.
∑ Terracing means shaping the earth in the form of levelled terraces to hold soil
and water. The edges of the terraces are planted with soil-anchoring plant
species. This method makes it possible to farm very steep hillsides. However,
this method is costly, requires expensive machinery or much hand labour.
(ii) Leaching By providing adequate drainage to flood-prone and irrigated lands,
salinity can be prevented.
Fig. 6.26 Wasteland reclamation practices
By leaching with more water, salt-affected lands can be recovered, especially in

the areas where groundwater table is not high.
(iii) Afforestation It means growing forests over culturable wastelands for the
first time. Previously there were no forests there due to lack of seeds or other adverse
factors.
Reforestation It means growing the forests over the lands where they were existing
earlier; and had destroyed or degraded by forest fires, overgrazing, excessive felling,
shifting cultivation, floods, waterlogging, soil erosion, etc.
(iv) Protecting the River Banks By providing stone, wooden or concrete
pitching or by plantation of trees/vegetation along the river banks, it is possible to
protect river banks against caving and cutting.
Controlling Formation of Gullies The gullies get widened due to excess run-off
water. This can be checked by constructing dams, diversion drains, bounds, etc.
(v) Protecting Soil Erosion by Providing Ground Cover After harvesting,
the crop residues are left on the ground. They resist wind and water from creating
erosion. The ground cover reduces soil temperature and evaporation in the hot
season. It thus protects the ground organisms which are helpful in aerating and
rebuilding the soil.
(vi) Ecological Succession This is a natural process of establishment or re-
establishment of an ecosystem. In ecological succession, the slow-growing native
grasses assist in reclaiming the minerally deficient soils in mining and industrial
wastelands.
(vii) Drainage It is required for waterlogged soil reclamation where excess water
is removed by artificial drainage.
In areas where waterlogging happens after heavy rains, surface drainage is
facilitated to remove the excess water.
Subsurface drainage is better because chances of evaporation of water leading to
accumulation of salt almost become nil in this method.
6.7.1 Consumerism and Waste Products

Consumerism is a process and habit of the chronic purchasing of new goods and
services, with less attention to their true need, durability, origin of the product or the
environmental impacts during manufacture and disposal.
Fig. 6.27 Relationship of population, consumerism, waste generation

and environmental degradation
In More Developed Countries (MDCs), population is less and resources are in

abundance. Lifestyle is luxurious and per capita consumption of resources is very
high. More consumption of resources result in more waste generation and greater
environmental degradation.
In Less Developed Countries (LDCs), population is large. Adequate resources are
not available for all, so per capita consumption is less. However, overall consumption
is high. Thus, environmental impact is same or slightly less in comparison to
MDCs.
For example, the population of India is 3.4 times more than that of USA but its
overall resource use and waste generation is less than 1/8th that of USA.
(A) Creators of Consumerist Culture
(i) Artificial Beauty Millions of people use soaps, detergents, hair dyes, skin-care
creams and other cosmetic items to enhance their beauty artificially. Manufacturers
have been able to create demands for these cosmetic items and the public is busy
spending their money for this temporary beauty enhancement.
Fashion Manufacturers of clothes, textiles, shoes and apparel keep changing
fashions to accelerate the speed of consumerism through advertisements.
(ii) Greed of Industry To make more profits, industry and large businesses
want to sell more products. Generally, products are made for a one-time use.
Through regular advertising a “throw-away society” has been created. This society
prefers disposable items discarding notions of inherent value, longevity and the
environmental consequences BITMAP
of manufacture and disposal
of the product. In the de- (i) (ii) (iii) (iv) (v) (vi)
veloped world, 200 billion Beauty
paper cups, bottles, cans and enhancement
desire
Industrial Time Mega Advertising Politics
greed unavailability shows
plastic cartons are thrown
away each year. Fig. 6.28 Creators of consumerism
(iii) More Money, Less Time Family ties, friendship, everything becomes
mediated through the spending of money on goods and gifts and services. A
generation is growing up without knowing what quality goods are. Relations are
promoted only as a vehicle of giving and taking gifts.
(iv) Mega Shows Manufacturers of items of consumerism (like automobiles,
televisions, radios, refrigerators, air conditioners, dishwashers, cosmetics) sponsor
megashows. They kindle passion and unquenchable desire for latest items through
prizes and other incentives.
(v) Advertising Advertising is designed to create both a desire to follow
fashions, and the resultant personal self-reward system based on acquisition. Thus,
a consumerist culture is not based on natural demand, but on a created demand.
(vi) Politics Consumerism is encouraged politically so that population remains
satisfied by material needs and politicians can do whatever they wish for.
(B) Drawbacks of Consumerism
Consumerism
(i) causes more pollution, creates more waste products, causes wasteful use of
material and energy,
(ii) helps lowest-wage, environ-
mentally unregulated over-
seas manufacturers,
(iii) promotes social unrest,
(iv) promotes riots, and other
criminalities, and
(v) leads to societal suicide. Fig. 6.29 Drawbacks of consumerism
(C) Measures to Prevent Excess Consumerism

Some of the measures to prevent excess consumerism include the following:
(i) Pigourian Taxes For encouraging industrial ecology and waste reduction,
manufacturers are taxed for some or all the cost of recycling or waste disposal.
(ii) Ecolabelling It involves the marking of products to indicate that they
are environmentally friendly. Ecolabelling assesses environmental impact and
communicates this to the consumer. It also encourages manufacturers to reduce the
impacts of their products. Ecomark is used in India for ecolabelling.
(iii) Green Marketing It involves communicating green image of the better,
environmental friendly products to the consumer. It helps in conserving the
environment and achieving better marketing niche. People also happily buy green
products like refrigerators that do not leak ozone-layer-depleting chlorofluoro
carbons (CFC’s) and consumes less electricity,
(iv) Self-awareness and Self-control
Having fewer things means
enjoying what you have
more and actually getting to
use it. It also helps in fewer
distractions from the essentials
such as food, family, nature,
study, friends. Fig. 6.30 Measures to prevent excess consumerism
6.8 ACTS FOR ENVIRONMENTAL PROTECTION
6.8.1 Environment Protection as a Common Goal for All

Paul Bigelow Sears once said, “How far must suffering and misery go before we see that
even in the day of vast cities and powerful machines, the Earth is our mother and that if
we destroy her, we destroy ourselves.”
So, we should act today for a better tomorrow. Adopt a strategy (like outlined below)
for environmental protection. Government, industry, public and law must have only
one goal, viz. environment protection.
(i) Industry Replace nonrenewable
inputs in energy with renewable ones.
(ii) Government Educate and in-
volve all in environmental protection
drive. They must act together to fight
corruption in government and ruth-
less exploitation by the industry.
(iii) Public Consume less, share
more, control population and reduce Fig. 6.31 Environment protection as a
pressure on natural resources. common goal for all
(iv) Law Take help from law, if needed, for protection of our environment.
6.8.2 Role of Government and Legal Aspects in Environmental

Protection
(A) Government Increased government intervention is a must for solving en-
vironmental problems because of the following reasons:
(i) The world is facing very serious environmental problems like loss of
biodiversity, global warming, water pollution, air pollution, etc.
(ii) The world is facing increased probabilities of natural disasters due to global
warming.
(iii) The health of millions of people is at risk if companies are left free to sell
their products, vehicles, etc., just for profits. This is because we are exposed
to thousands of chemicals a year, many of which interact in ways that are not
yet fully understood.
(B) Legal Aspects The Ministry of Environment and Forests (MoEF) in India
is the apex administrative body for
(i) undertaking conservation and survey of fauna, flora, forests and wild life;
(ii) formulating the environmental policy framework in the country;
(iii) planning, promotion, co-ordination and overseeing the implementation of
environmental and forestry programmes; and
(iv) regulating and ensuring environmental protection.
The responsibility for prevention and control of industrial pollution is primarily
executed by the Central Pollution Control Board (CPCB) at the central level which
is a statutory authority, attached to the MoEF. The State Pollution Control Boards
and the State Departments of Environment are the designated agencies to perform
the function at the state level. The administrative framework in India for protection
of the environments is shown in Fig. 6.32.
Fig. 6.32 Administrative framework for environment protection in India

6.8.3 Environment (Protection) Act, 1986

It is the umbrella legislation which authorises the Central Government to
(i) protect and improve environmental quality,
(ii) control and reduce pollution from all sources, and
(iii) restrict or prohibit the selling and/or operation of any industrial facility on
environmental grounds.
According to the Act, the term “environment” includes water, air and land and
the inter-relationship which exists among and between water, air, land, human beings,
other living creatures, microorganisms, plants and property.
The main provisions of the Act are given below:
(i) The Central Government shall have the power to take all such measures as
it deems necessary or useful for the purpose of protecting and improving
the quality of the environment and preventing, controlling and decreasing
environmental pollution.
(ii) No person carrying on any industry, operation or process shall discharge
or emit any environmental pollutants or permit to do so in excess of such
standards as may be prescribed.
(iii) Where the discharge of any environmental pollutant in excess of the
prescribed standards occurs or is bound to occur due to any accident or
other unexpected act or event, the person responsible for such discharge
and the person in charge of the place at which such discharge occurs or is
expected to occur, shall be bound to prevent or reduce the environmental
pollution caused as a result of such discharge and shall also immediately
inform the fact of such occurrence or fear of such occurrence; and be bound,
if called upon, to render all assistance to such authorities or agencies as may
be advised.
(iv) No person shall handle or cause to be handled any hazardous substance
except in accordance with such procedure and after complying with such
safeguards as may be prescribed.
(v) The Central Government or any officer empowered by it in this behalf, shall
have power to take, for the purpose of analysis, samples of air, water, soil or
other substance from any premises, factory, etc., as may be prescribed.
(vi) The Central Government may, by notification in the Official Gazette,
establish one or more environmental laboratories; and recognise one or
more laboratories or institutes as environmental laboratories to carry out the
functions assigned to an environmental laboratory under this Act.
(vii) Whoever fails to comply with or violate any of the provisions of this Act, or
the rules made or orders or directions issued thereunder, shall, in respect of
each such failure or violation, be punishable with imprisonment or with fine
or with both.
6.8.4 Air (Prevention and Control of Pollution) Act, 1981

This is an act to provide for the prevention, control and reduction of air pollution
in the country so as to preserve the quality of air.
The salient features of the Air (Prevention and Control of Pollution) Act 1981
are given below:
(i) Act is applicable to the whole of India.
(ii) Under Section 19 of the Act, the State Government in consultation with the
State Pollution Control Board (SPCB) has the power to declare Air Pollution
Control Area, in which provisions of the Act shall be applicable.
(iii) As per provisions in Section 21(1) and (2), no person can establish or operate
any industrial plant without the previous consent of the State Pollution
Control Board.
(iv) Every application for consent shall be made in Form I and shall be accompa-
nied by a prescribed fee. Within a period of four months after the receipt of
application, the Board shall complete the formalities to either refuse or grant
consent. During the course of processing consent for the application, the Board
may seek any information about the industry after giving notice in Form II.
(v) Under Section 22, 22(A) operating any industrial plant so as to cause
emission of any air pollutant in excess of standard laid down by the State
Board is liable for legal action by the Board.
(vi) Under Section 2(a), the term air pollutant is defined as any solid, liquid or
gaseous substance present in the atmosphere in such concentration as may be
or tend to be injurious to human beings or other living creatures or plants or
property or environment.
Power of State Government
Under Section 19, the State Government may, after consultation with the State
Board, by notification in the official gazette, declare, in such manner as may be
prescribed, any area or areas within the state as air pollution control area or areas for
the purposes of this Act.
Under Section 21.3, no person shall without the previous consent of the State
Pollution Control Board, establish or operate any industrial plant in an Air Pollution
Control Area.
Under Section 22.4, no person operating any industrial plant in any Air Pollution
Control Area shall discharge or cause or permit to be discharged, the emission of
any air pollutant in excess of the laid-down standards by the State Pollution Control
Boards.
Under Section 19.1, the State Government after consultation with the State
Pollution Control Board, may
(i) Prohibit burning of any material causing or likely to cause air pollution in an
Air Pollution Control Area
(ii) Prohibit the use of any appliance or fuel causing or likely to cause air
pollution in an Air Pollution Control Area
6.8.5 Wildlife Protection Act, 1972

(A) Objectives The objectives of the Wildlife Protection Act are
(i) to maintain essential ecological processes and life-supporting systems;
(ii) to preserve biodiversity; and

(iii) to ensure protection and conservation of wildlife.
(B) Salient Features
(i) Under Section 3, the appointment of Director, Chief Wildlife Warden and
other officers is done by the Central Government.
(ii) Under Section 6, Wildlife Advisory Board is constituted by the State
Government or the Union Territory Administration. Under Section 7, the
Wildlife Advisory Board shall meet at least twice a year.
(iii) The duties of the Wildlife Advisory Board, under Section 8, are to advise the
State Government about
(a) The selection of areas to be declared as.
∑ National parks under Section 35,
∑ Sanctuaries under Section 18, etc.
(b) The formulation of the policy for protection and conservation of
wildlife and specified plants
(c) The measures to be taken for harmonising the protection and
conservation of wildlife with the needs of the tribals and other forest
dwellers
(iv) Under Section 44, the Act prohibits dealing in animal articles without
licence.
(v) Under Section 38 A, the Central Government shall constitute the Central
Zoo Authority which has various roles or functions as described in Section
38 C.
(C) Major Highlights of the Wildlife Protection Act, 1972
(i) It provides for protection to listed species of flora and fauna and establishes
a network of ecologically important protected areas.
(ii) The act consists of 60 sections and VI schedules divided into eight chapters.
(iii) It empowers the central and state governments to declare any area a wildlife
sanctuary, national park or closed area. Industrial activities are banned in
these protected areas.
(iv) It provides for authorities to
(a) administer and implement the Act;
(b) regulate the hunting of wild animals;
(c) protect specified plants, sanctuaries, national parks, etc., and
(d) restrict trade in wild animals or animals articles.
(v) The Act prohibits hunting of animals except with permission of an authorised
officer when an animal has become dangerous to human life or property or
as disabled or diseased as to be beyond recovery.
6.8.6 Forest (Conservation) Act, 1980

In 1980, the Forest (Conservation) Act was enacted for providing protection to
forests and to regulate diversion of forestlands for nonforestry purposes.
Salient Features
(i) Prior approval of the Central Government is essential for de-reservation of
forest lands and/or diversion of forest lands for nonforestry purposes.
(ii) It is a regulatory act, not prohibitory.
(iii) The Forest (Conservation) Act is an interface between conservation and
development.
(iv) It permits sensible and regulated use of forestland for nonforestry purposes.
During 1950–80, the rate of diversion of forestland for nonforestry purposes
was 1.5 lakh hectares per annum. After enactment of the Forest (Conservation) Act,
1980, the rate came down to about 35 thousand hectares per annum.
At the time of granting approval under the Forest (Conservation) Act, following
conditions are insist upon:
∑ Compensatory afforestation
∑ Treatment of catchment area
∑ Reclamation of mining area in phases
∑ Provisioning for safety zone area
∑ Rehabilitation of project affected families
∑ Plan for wildlife management, etc.
On the directions of the apex court in 2002, a new present value of the forestland
being diverted is being charged from the user agencies.
6.8.7 Water (Prevention and Control of Pollution) Act, 1974

“As defined in the Act, water pollution means such contamination of water or such
alteration of the physical, chemical or biological properties of water or such discharge
of any sewage or trade effluent or of any other liquid, gaseous or solid substance into
water (whether directly or indirectly) as may, or is likely to, create a nuisance or render
such water harmful or injurious to public health or safety, or to domestic, commercial,
industrial, agricultural or other uses or to the life and health of animals or plants or of
aquatic organism.”
(i) The water (Prevention and Control of Pollution) Act was enacted for prevention
and control of water pollution and maintaining or restoring of wholesomeness
of water.
The Central and State Pollution Control Boards have been constituted
under sections 3 and 4 of the later Act respectively.
(ii) Obligations on the part of industries and local bodies are
(a) To obtain prior consent to establish and operate industry for new
discharge of domestic sewage or trade effluent under section 25 of the
Act
(b) Board within four months will either refuse or grant consent
(iii) Power of State Board:
(a) To obtain information under Section 20
(b) Carry out any related work under Section 30
(c) Collect and analyse samples of streams/wells or trade effluent under
sections 17(2) and 52
(d) To give direction for closure/prohibition or regulation under Section

33A
(e) Enter and inspect any place, examine any plants/records, etc., and seize
if necessary under Section 23
6.9 CARBON CREDITS

(i) An industrial house needs to meet its pollutant emission limit.
(ii) The industrial house invests in carbon offsets (either directly or usually
through an offset provider).
It means, the industrial house invests in an emission reduction project
outside of its sector. Carbon-offsets programs can include
∑ Renewable energy-sustainable development projects,
∑ Reforestation projects
∑ Methane capture/combustion projects
(iii) The Industrial house receives carbon credits for its investment in the form of
a carbon-offset certificate.
One carbon credit = one tonne of greenhouse gas emission reduction
Fig. 6.33 Carbon credit concept
Benefits of Carbon-Credits Concept

(i) Global warming reduction
(ii) Desertification reduction
(iii) Environmental awareness
(iv) Biodiversity protection
(v) Reforestation
6.10 INDUSTRIAL SYMBIOSIS

Industrial symbiosis is a collaborative enterprise is which the byproducts or waste of one
industry become valuable resources for one or several other industries.
Industrial symbiosis is sharing of services, utility, and by-product resources

among industrial units in order to add value, reduce costs and improve environment
(Fig. 6.34).
Fig. 6.34 Industrial symbiosis

Benefits
(i) Economic Benefits
(a) Industrial symbiosis turns a disposal cost into an income stream.
(b) It helps in reducing the cost of raw materials.
(c) It maximises use of under-utilised resources and facilities.
(d) It helps in spreading costs of new infrastructure (e.g. infrastructure cost of
effluent treatment in shared).
(ii) Environmental Benefits
(a) Industrial symbiosis reduces virgin resource use and net waste generation
without compromising economic activity.
(b) Industrial symbiosis is a major step towards a more sustainable society.
(iii) Other Benefits
(a) Industrial symbiosis helps in improving public relations.
(b) It facilitates integration of business.
(c) It helps in safeguarding and creating employment.
(d) It helps in sharing of laboratories, workshops, training facilities and other
services.
Kalundborg is a medium-sized town in Denmark. Kalundborg’s industrial
symbiosis comprises eight core companies: (i) Power station, (ii) Refinery,
(iii) Pharmaceutical plant, (iv) Recycling company, (v) Sulphuric and plant,
(vi) Municipality, (vii) Plasterboard factory, and (viii) Cement factory. Each
company is bound to each other via an intricate network of flows; flows of steam,
natural gas, water, gypsum, sludge and fly ash (Fig. 6.35).
Fig. 6.35 Industrial symbiosis in Kalundborg

Excess steam from power stations is exported to district heat and power supply,
refinery, pharmaceutical plant and plasterboard factory. They use it as incoming
heat source and export it back to the power station as condensed steam for cooling
the plant.
The plasterboard factory receives surplus natural gas as an input energy source
from refinery and industrial plaster as an input material source from power station.
Calcium and recycled treated waste water are added to the sulphur extracted from
the flue gas at power station to form industrial plaster.
CaCO3 + SO2 + 1/2 O2 + 2H2O Æ CaSO4.2H2O + CO2
Insulin production at pharmaceutical plant releases yeast slurry material which
is exported to surrounding farms as pig fodder. This replaces approximately 70%
of the soy proteins in traditional food mixes. Pharmaceutical plant adds water,
lactic acid bacteria and sugar to the yeast in order to make it a more effective and
alternative food (Fig. 6.35).
6.11 INITIATIVES AND ROLES OF

NONGOVERNMENTAL ORGANISATIONS
(NGOs) IN ENVIRONMENTAL PROTECTION
Privately owned organisations involved in providing financial and technical assistance
to less developed countries are known as NonGovernmental Organisations (NGOs).
They have no participation or representation of any government. An NGO is

any nonprofit, voluntary citizen’s group which performs a variety of services and
humanitarian functions.
6.11.1 Functions and Advantages of NGOs

(i) They are good at reaching and mobilising the poor and remote communities.
(ii) They work with and strengthen local institutions.
(iii) They help empower poor people to gain control of their lives by counselling,
support service, training, micro-credit, etc.
(iv) They carry out projects at lower costs and more efficiently than government
agencies.
(v) They promote sustainable development, through economical development,
social development and environmental protection.
(vi) They do funding of projects.
(vii) They help in critical analysis of social environments.
6.11.2 Roles of NGOs in Environmental Protection

(i) NGO’s help in increasing local economic diversity.
(ii) They help in development of local markets, local production, local processing
of previously imported goods, and greater cooperation among local economic
entities. Thus, they help on attaining self-reliance.
(iii) They educate people on reduction in the use of energy and careful
management with recycling of waste products.
(iv) They educate and motivate local people to protect and enhance biological di-
versity. They make them understand careful stewardship of natural resources.
(v) They give commitment of the sustainable communities to social justice.
The relationship between NGO functions, empowerment and sustainable
community development is illustrated in Fig 6.36.
NGO Functions
Fig. 6.36 Theoretical framework of the functions of NGOs in promoting

environmental protection and sustainable community development
NGOs, through some programmes and functions such as microfinance, capacity
building and self-reliance, help communities to be empowered and finally contribute
towards environmental protection.
6.12 ISSUES INVOLVED IN ENFORCEMENT OF

ENVIRONMENTAL LEGISLATION
Regulatory measures in the form of legislation check environmental degradation.
They also lead to the enacting of laws at the national or international levels to
prevent pollution. To protect the environment, the role of the judiciary lies in
formulation and enforcement of effective laws. The judiciary alone cannot improve
the environment unless the states and citizens do their duties and obligations.
Some important issues in the enforcement of environmental legislations are given here.
(i) Public Apathy In contrast with conventional crimes such as rape, murder,
dacoity, etc., pollution is treated as a white-collared crime. While conventional
crimes are always taken seriously, the crime of pollution is generally taken for
granted.
(ii) Limitations of Regulating Agencies
Poaching It is a big national problem despite the existence of the Wildlife Act.
The Wildlife Department has no provision to punish poachers and unauthorized
hunters unless they are caught red handed. In case they are caught, the standard
excuse given by armed poachers is that they carried guns for self-defence from
dangerous wild animals. Penalties by the Wildlife Department are nominal cash
fines. Rich offenders continue poaching by paying such nominal cash fines to the
Wildlife Department.
Water Pollution The chairman of the state pollution control board is the key
person for the enforcement of the Water Act, 1974. He/she should be professionally
qualified and appointed on a full-time basis. However, several State Pollution Control
Boards are headed by part-time chairpersons without requisite qualifications and
experience. Often, the member secretaries of the Pollution Control Boards are
drawn either from the administrative service or even from the forest service. They do
not have the required technical background in pollution control. Thus, it becomes
difficult for them to provide proper leadership and guidance to their subordinates.
The enforcement action in such situations is obviously weak.
(iii) Legal Loopholes
(a) The legal provision for penal action against the polluters requires that the
State Pollution Control Board has to file a case before the lower court for
action against a polluting unit. However, the lower courts are too busy to
devote enough time for environment-related litigations. As a consequence,
thousands of cases filed by the State Pollution Control Boards are still
pending for years together. In some cases where decisions have been taken,
the polluters were given the benefit of doubt due to absence of sufficient
proof.
(b) For prevention of pollution, a provision is available for a citizen to approach
a court. For this, the citizen is required to give a notice of not less than 60
days to the government, of his/her intention to make a complaint. If the
government does not act on the notice, then only the citizen can go to the
court. For meaningful result, the court must give directives to the government
or the enforcing authority to collect a sample and submit a report.
Thus, this exercise would give the culprit a period of at least 60 days to
clean up all traces of its offence and prepare itself for sample collection.
(c) The Factories Act, 1948, is an important legislation which provides for
certain measures with respect to the industrial safety, health of the workers
and welfare measures.
However, safety standards and maintenance procedures at various
industries are not maintained. India has seen and suffered Bhopal tragedy
on the night of December 23, 1984 which is considered the worst industrial
disaster in history. The Bhopal tragedy was the result of a combination
of legal, organisational, technological, and human errors. The accident
occurred when toxic Methyl IsoCyanate (MIC) gas was accidentally released
into the atmosphere. About 1 lakh people died and more than 2 lakh people
were severely disabled. Even after 26 years of the accident, thousands of the
poorest members of the population of shanty towns are still suffering.
(iv) Lack of Knowledge While urban citizens cry for stopping pollution and
consumerism from one side, they watch television, see advertisements, purchase
new vehicles, gadgets, luxury items and cosmetics whose ecological footprints are
large. These urban citizens unknowingly became creators of pollution.
(v) Lacuna in Implementation Pollution Control Boards cannot take action
against municipal corporations or other civic bodies because they are not empowered
to do so. These Pollution Control Boards are empowered to stop industrial water
pollution but they cannot fight with rich industrialists. Thus, the public is forced to
suffer from use of polluted water.
Despite the various legislations, there is a depletion of forest resources because
of commercial exploitation. The present and future generations are bound to suffer
from deforestation-linked flood, soil erosion, siltation of water bodies, loss of
biological and genetic diversity, etc.
(vi) Intellectual Indifference In the Environment Protection Act, all power
and authority is reserved in the hands of the Central Government. For the efficient
execution of the provisions of the Act, this excessive centralisation is a major burdle.
(vii) Limitations of Environmental Risk Assessment Scientific knowledge
regarding the potential impacts of Persistent Organic Pollutants (POPs) and
endocrine disrupting chemicals on human health and environment is not completely
understood because of the complexity of natural ecosystems and limitations in
experimental design.
For environmental protection, The Precautionary Principle is applied in such
circumstances where there are reasonable grounds for concern that an activity is, or
could, cause harm but risk is uncertain.
The Precautionary principle directs that action should be taken to correct a problem the
moment there is evidence that harm may occur, not after the harm has already occurred.
For example, the German Government in 70’s ordered to reduce power plant
emissions when they realised that forests were suddenly dying because of the acid rain.
Thus, lack of full scientific certainty shall not be used as a reason for postponing
cost-effective measures to prevent environmental degradation from substances or
activities which cause threats of serious or irreversible damage.
(viii) Poverty Affordable food, shelter, clothing, medicine and minimum

education for their children are the high-priority necessities of the poor. They do
not have enough money to practice environmental conservation strategies used by
the rich. They exploit the environment to generate income. For growing crops, they
encroach watershed areas. They live in slums as they cannot afford proper sanitation
and waste treatment. They can only purchase cheaper products made in factories
where proper pollution control devices are lacking. Thus, survival activities of the
poor indirectly contribute to environmental degradation.
According to Polluter-Pays Principle, those who pollute the environment must pay for
the damages they have caused. This principle will burden the poor in order to create
a better environment for the rich to enjoy. If enforced, this principle will certainly
widen the real income gap and can even be interpreted as socially undesirable or
morally unjust.
(a) Suppose forest encroachment is conducted by the poor landless farmers.
According to the Polluter-Pays Principle, they will be liable for causing
flooding, soil sedimentation in irrigation and/or hydropower dams.
However, the wealthy people or factory owners will benefit from keeping
the forests intact, namely in terms of water supply or hydropower electricity,
or as a recreation site. Thus, according to the Beneficiary-Pays Principle, the
rich should pay for the cost of forest conservation.
(b) We know that for reducing air pollution, commuters should use public
transport instead of personal vehicles. The poor commuters use public buses
not for reducing pollution but because they cannot afford personal vehicles.
In order to finance better quality buses which cause minimum air
pollution, the Polluter-Pays Principle requires the poor commuters to pay a
higher charge as they use public buses.
The alternative Beneficiary-Pays Principle argues that cleaner and less
smoky buses should be financed by all city residents and not just by bus
commuters. This is because everyone will enjoy the clean air.
6.13 ANIMAL HUSBANDRY

Animal husbandry is the science of taking care of domestic animals that are used primarily
as food or product sources. Anyone who takes care of domesticated animals especially
in large groups, is practicing animal husbandry. Animal husbandry provides an
understanding of how to care for and manage domestic animals so that the animal’s
requirements for good health and welfare, and humans’ requirements for the use of
these animals are met.
Modern animal husbandry is concerned with (a) increasing efficiency by increasing
the number of animals raised per unit area; (b) using antibiotics to increase animal
growth rates; and (c) decreasing labor costs by automated animal feeding, watering,
housing, etc.
Note: Livestock (also cattle) refers to a domesticated animal raised in an agricul-
tural setting to produce food, fibre, or labour.
Case Study
Environmental and Social Impact of Livestock Revolution
As per the Stanford University (March 2010) report on “Environmental and
Social Impact of Livestock Revolution” Science daily: Worldwide more than
1.7 ¥ 109 animals are used in livestock production. They occupy more than
25% of the earth’s land. Production of animal feed consumes about 33% of
total arable land. Livestock production accounts for approximately 40% of the
global agricultural gross domestic product. The livestock sector, including feed
production and transport, is responsible for about 18% of all greenhouse gas
emissions worldwide.
6.13.1 Impacts of Livestock Revolution on Humanity

Although about 1 ¥ 109 people worldwide derive at least some part of their livelihood
from domesticated animals, the fast growth of commercialised industrial livestock
has reduced employment opportunities for many. Many small, rural producers from
India and China are under additional pressure from health authorities to meet the
global food-safety standards.
Poultry, pork, beef, etc., provide about 33% of humanity’s protein intake, but
the impact on nutrition across the globe is highly variable. Too much animal-based
protein is not good for human health, while too little is a problem for those on a
protein-starved diet (applicable mainly for developing countries) (Fig. 6.37).
,
Fig. 6.37 Impacts of animal source foods on children
Human health is also affected by pathogens and harmful substances transmitted

by livestock.
6.13.2 Environmental Concerns of Animal Husbandry

The livestock sector is a major environmental polluter due to the following
considerations:
(i) Much of the world’s pastureland has been degraded by grazing or feed
production.
(ii) Many forests have been clear-cut to make additional farmland.

(iii) Feed production for animals requires intensive use of water, fertilisers, fossil
fuels, pesticides, etc.
(iv) Only 33% of the nutrients fed to animals are absorbed, and so animal waste
is a leading factor in the pollution of land and water resources. For example,
the total phosphorous excretions of animals are estimated to be 7–9 times
greater than that of humans, with detrimental effects on environment.
(v) The poultry, pork and beef industries emit large amounts (about 51%) of
greenhouse gases (CO2, CH4, etc.) and are responsible for climate change.
(vi) The quality of surface water and groundwater gets degraded by disposal of
organic wastes and liquid effluents of livestock.
(vii) Huge quantity of fossil fuels are used to transport feed for livestock industry,
applicable mainly for developed countries.
Notes:
∑ A person in America switching from a typical meat diet to a vegetarian
diet with the same number of calories would prevent the emission of
1485 kg of carbon dioxide.
∑ A beef animal consumes about 100 kg of hay and 4 kg of grain per 1 kg of
beef produced. It takes about 1000 litres of water to produce 1 kg of hay
and grain, thus about 100, 4000 litres of water is required to produce 1 kg
of beef meat.
6.13.3 Solutions
(i) Governments should implement policies that provide incentives for better
management practices with focus on efficient water and fertiliser use, and
land conservation.
(ii) Reduce or refuse the consumption of meat. Celebrate meat-free days.
Promote vegetarian eating options.
(iii) Keep manure and urine away from household areas and water bodies. Collect
and store manure for composting. Install a biogas plant.
(iv) Restrict animal access to fragile areas, allow rotational grazing so that plant
re-growth is facilitated.
(v) Use integrated pest-management techniques. Apply fertilisers and pesticides
at the correct time, in correct amounts to promote land use optimisation.
∑ Sustainable development means meeting the needs of the present without
compromising the ability of future generations to meet their own needs.
∑ When the sum total of nature’s resources (natural capital) is used up faster than it can
be replenished, degradation of the environment occurs. However, if human activity
only uses nature’s resources at a rate at which they can be replenished naturally,
sustainability occurs.
∑ A lifestyle that attempts to reduce an individual’s or society’s use of the earth’s natural
resource and his/her own resources is known as a sustainable lifestyle.
∑ Equitable use of resources for sustainable lifestyle requires that the rate of use
of renewable resources do not exceed regeneration rates and rates of use of
nonrenewable resources do not exceed rates of development of renewal substitutes.
∑ Urbanisation is defined as movement of people from rural to urban areas with
population growth equating to urban migration or it can also be defined as the
physical growth of urban areas as a result of global change.
∑ Rainwater harvesting means collecting rainwater and storing/conserving it for a later
use.
∑ Watershed is a geographic area of land that collects, stores, and releases water.
∑ Watershed management refers to the conservation, protection and restoration of a
watershed to secure water—both in quantity and quality for drinking, sanitation and
agriculture in a sustained manner.
∑ Weather is the reflection of atmospheric humidity, temperature and rainfall.
∑ Climate is the average weather pattern over longer duration in a place.
∑ Greenhouse effect is a process by which infrared radiation leaving the earth’s surface
is trapped by some greenhouse gases; so the temperature is higher than it would be
if direct heating by solar radiation were the only warming mechanism.
∑ Greenhouse gases are gases in an atmosphere that absorb and emit radiation within
the thermal infrared range. Examples: Carbon dioxide, nitrous oxide, methane, water
vapour, ozone.
∑ Global warming means a rise in temperature over the earth’s surface. It is primarily
caused by CO2 emission by man-made activities.
∑ Acid rain is rain which is unusually acidic (pH of less than the natural range of 5 to
6); caused mainly by atmospheric pollution with sulphur dioxide and nitrogen
compounds.
∑ The gradual thinning of the ozone layer and ozone-hole formation occurs by the
destruction of ozone due to its reactions with nitric oxide, chlorine, hydroxyl radicals,
etc., in the stratosphere.
∑ Holocaust means large-scale destruction of human lives by intense heat and fire.
∑ Wasteland reclamation is the process of converting sterile, barren wasteland into
something that is fertile and suitable for habitation and cultivation.
∑ Consumerism is a process and habit of the chronic purchasing of new goods and
services, with less attention to their true need, durability, origin of the product or the
environmental impacts during manufacture and disposal.
∑ Water pollution means such contamination of water or such alteration of the physical,
chemical or biological properties of water or such discharge of any sewage or trade
effluent or of any other liquid, gaseous or solid substance into water (whether directly
or indirectly) as may, or is likely to, create a nuisance or render such water harmful or
injurious to public health or safety, or to domestic, commercial, industrial, agricultural
or other uses or to the life and health of animals or plants or of aquatic organism.
∑ Industrial symbiosis is a collaborative enterprise is which the by-products or waste of
one industry become valuable resources for one or several other industries.
∑ Privately owned organisations involved in providing financial and technical assistance
to less developed countries are known as Non-Governmental Organisations (NGOs).
∑ Animal husbandry is the science of taking care of domestic animals that are used
primarily as food or product sources.
∑ Livestock (also cattle) refers to a domesticated animal raised in an agricultural setting
to produce food, fibre, or labour.
EXERCISES
Based on role of government and 2. Comment on the urban energy prob-
legal aspects lems and discuss the effect of overpop-
1. Describe the power of the state gov- ulation over energy problems in India.
ernment to declare pollution control Based on water conservation
areas and restrictions or use of certain 1. Discuss various water conservation
industrial plants as given in the Air Pre- techniques that can be practiced by
vention and Control of Pollution Acts. individuals.
2. Briefly discuss the salient feature 2. What are the major approaches to
of the Environment (Protection) Act, conserve water resources? Comment
1986. on water harvesting methods in India.
3. Discuss, in brief the salient features 3. Define watershed management and
of the Air (Prevention and Control of explain its objectives.
Pollution) Act, 1981. 4. Describe the parameters of water
4. Briefly discuss the salient features quality standards for drinking water in
of the Forest (Conservation) Act, 1980. India and state their significances.
5. Write down the major highlights of 5. What is ‘rainwater Harvesting’?
the Wildlife Protection Act of India. Name and discuss in brief the types of
6. Discuss the role of government and le- rainwater harvesting.
gal aspects in environmental protection. 6. What are the programs to uplift the
7. Which are the government organi- status and lifestyle of people living in
sations/departments responsible for remote areas?
the protection of the environment? 7. How is a habitation pattern devel-
Write brief details of these. oped? List all environmental factors
8. Write the aims and objectives of governing human settlement.
‘Family Welfare Programmes’.
Based on global environmental
9. Discuss briefly the salient features
pollution problems
of the Water (Prevention and Control
1. There is an impact of excessive
of Pollution) Act, 1984.
use of fossil fuels on the environment.
10. Mention two important environ-
Comment and justify the statement.
mental laws.
2. How is the ‘acid rain forming’? What
11. Discuss briefly the provision of the
are its effects on the atmosphere?
following acts:
3. Explain, greenhouse effect by
(a) Water (Prevention Control of
drawing sketch.
Pollution) Act, 1974
4. Write short notes on (a) acid rain
(b) Air (Prevention and Control of
(b) environmental degradation.
Pollution) Act, 1981
4. Enlist all global environmental pol-
(c) Wildlife Protection Act 1971
lution problems. Describe global warm-
(d) Forest Conservation Act of 1980
ing and greenhouse effects in detail.
Based on sustainable development 6. Explain the term “environmental
and urbanisation degradation” and discuss the role of
1. What is sustainable environment? advanced technology in the degradation
Define the carrying capacity of the of the environment.
earth.
7. Compare the effect of different (b) What is global warming? Enlist its
greenhouse gases in global warming. consequences.
8. What is ozone? How is it formed? 10. Write various mechanisms involved
Describe the main causes of depletion in the formation and depletion of ozone
of ozone layer and briefly comment in the atmosphere. What are the con-
over control measures taken to prevent sequences of depletion of ozone layer?
further depletion at the international How can the ozone layer be protected?
level.
Based on Initiatives by Non-
9. (a) What is acid rain? Write a brief
Governmental Organisations
note on effects of acid rain on the
1. Discuss of role of NGOs in
environment.
environmental protection.

I. Fill in the Blanks 15. Global warming contributes to rise
1. The Environment (Protection) Act in sea level due to _________ of ocean
was passed in the year _________. and melting of _________ .
2. By using a bicycle instead of a car, 16. The thinning of stratospheric ozone
we _________ energy. layer during springtime is called ______ .
3. The Air (Prevention and Control of 17. World Ozone Layer Preservation
Pollution) Act, _________ . Day is celebrated on _________ .
4. The Water (Prevention and Control 18. The greenhouse gases are CO2,
of Pollution) Act, _________ . CH4, O3, CFC and _________ .
5. Wildlife (Protection) Act, ________. 19. World Population Day is recalled
6. The Forest (Conservation) Act, on _________ .
_________. 20. World Peace Day is recalled on
7. International Literacy Day is recalled _________ .
on _________.
8. International Women’s Day is re-
called on _________.
9. Chlorofluorocarbon releases a
A.
chemical harmful to ozone is ________ .
10. Greenhouse effect is related to Column I Column II
_________ . 1. 1972 (a) Wildlife (Protection) Act
11. Increasing industrialisation is
2. 1974 (b) The Water (Prevention
causing much danger to human life by
and Control of Pollution) Act
_________ .
12. _____ is related to global warming. 3. 1980 (c) The Forest (Conserva-
13. The best known substance re- tion) Act
sponsible for ozone-layer depletion is 4. 1981 (d) The Air (Prevention and
______ . Control of Pollution) Act
14. Automobile pollution also causes 5. 1986 (e) Environment (Protec-
_________ . tion) Act
B. (d) Article 48A and Article 51A (g)

Column I Column II 5. Greenhouse effect is related to
(a) global warming
1. Acid rain (a) SO2 and NO2 (b) green trees around house
2. Global warming (b) Deforestation (c) grasslands
3. Urbanisation (c) Greenhouse (d) greenery in city
gases 6. Which of the following is not a
green-house gas?
4. Population (d) Food crisis
(a) Carbon dioxide
explosion
(b) Oxygen
C. (c) Methane
Column I Column II (d) Chlorofluoro carbons
1. The gas having (a) CFC-11 7. Ozone layer is present in the
the highest global- (a) thermosphere
warming potential (b) mesosphere
(c) stratosphere
2. The gas having (b) HCFC (d) troposphere
the highest ozone- 8. Formation of hole in the ozone layer
depleting potential is maximum over
3. The gas responsible (c) CO2 (a) India (b) Pakistan
for acid rain (c) Europe (d) Antarctica
4. The gas responsible (d) SO2 and 9. The primary cause of acid rain
for global warming NO2 around the world is
(a) SO2 (b) CO2
III. Multiple Choice Questions (c) CO (d) O3
1. The entire National Capital Territory 10. The average life expectancy around
of Delhi has been declared as water the world is presently
pollution prevention control area under (a) stabilizing (b) increasing
________ of the Water Act. (c) not changing (d) decreasing
(a) Section 19 (b) Section 21 11. Atmosphere of metropolitan cities
(c) Section 23 (d) Section 24 is polluted by
2. The Forest (Conservation) Act (a) pesticides (b) radiations
extends to the whole of India except (c) automobile exhaust
(a) Haryana (d) domestic waste
(b) Jammu and Kashmir 12. Production, transformation and
(c) Delhi (d) UP use of energy are the major problems
3. The provisions for environmental of
protection in the constitution were (a) industrial activity
made in (b) acid rain
(a) 1947 (b) 1950 (c) global warming
(c) 1976 (d) 1982 (d) sustainable development
4. The provisions for environmental 13. Agricultural activities such as har-
protection in the constitution were vesting, heating, etc., are direct con-
made under sumers of
(a) Article 21B (b) Article 5A (a) water (b) energy
(c) Article 27B (h) (c) air (d) heat
14. Benefits of EIA are 3. Privately owned organisations in-

(a) cost-saving volved in providing financial and tech-
(b) improved project performance nical assistance to less developed coun-
(c) healthier local environment tries are known as nongovernmental
(d) all organisations. True/False
15. Objectives of sustainable develop- 4. Community-based environmen-
ment are tal education is capable of protecting
(a) social development health and habitat from the various
(b) economic development problems existing in the world.
(c) environment protection True/False
(d) all 5. The act or process of imparting or
acquiring knowledge, skill or judgement
by women is known as women’s
education. True/False
1. Only legislation is not sufficient for
6. Ozone is a major constituent of
the control of environmental pollution.
photochemical smog. True/False
True/False
7. Ozone protects us from harmful UV
2. Increased government intervention
radiation of the Sun. True/False
is a must for solving environmental
problems. True/False

I. Fill in the Blanks 20. January Ist
1. 1986 2. Conserve
II. Matching the terms
3. 1981 4. 1974
5. 1972 6. 1980 A. 1. (a) 2. (b) 3. (c) 4. (d) 5. (e)
B. 1. (a) 2. (c) 3. (b) 4. (d)
7. September, 8th 8. March, 8th
C. 1. (b) 2. (a) 3. (d) 4. (c)
9. Chlorine
10. Global warming III. Multiple Choice Questions
11. Air and water pollution 1. (a) 2. (b) 3. (c) 4. (d)
12. Greenhouse effect 5. (a) 6. (b) 7. (c) 8. (d)
13. CFCs 14. Air pollution 9. (a) 10. (b) 11. (c) 12. (a)
15. Thermal expansion, glaciers 13. (b) 14. (d) 15. (d)
16. Ozone hole
17. September, 16th IV. True or False
1. True 2. True 3. True 4. True
18. Nitrous oxide 19. July 11th
5. True 6. True 7. True
7
HUMAN
POPULATION AND
THE ENVIRONMENT
Learning Objectives
∑ explain the meaning of population growth and population stabilisation
∑ describe population explosion in the Indian context
∑ enumerate and describe the major periods of growth of human population
∑ write a short note on methods of projection of population
∑ explain the meaning of value and value education
∑ describe the role of information technology in environment and human
health
∑ describe the various schemes launched for women’s education in India
∑ state the aims and objectives of ‘Family Welfare Programmes’
∑ describe the role of information technology in environment and human
health
7.1 POPULATION GROWTH

Population is a group of organisms of a particular species, sharing a particular
characteristic of interest, most often that of living in a given area at a specific time.
Population growth is the change in a population per unit time. Population growth
can be positive, static or negative.
7.1.1 Major Periods of Growth of Human Population
As of November 2011, the human population of the world is 7 billion (estimated by
the United States Census Bureau).
World Population Milestones
World Population reached:
1 billion in 1804
2 billion in 1927 (123 years later)
The growth of human population is summarised in the following four periods:

(i) Hunter-gatherer Era It refers to the earliest period of human history.
Humans were mainly hunters and used to live in forests.
(ii) Agricultural Era Humans learnt agricultural practices and cultures were
evolved.
(iii) Era of Industrial Revolution This era was of scientific developments and
industrial advances.
(iv) Modern Industrial Era Scientific and industrial revolution touched every
sphere of human life: health, education, living style, etc.
Human populations in these periods are summarised in Table 7.1.
Table 7.1 Major periods of growth of human population
Era Period Total population
(i) Hunter-gatherer Era (From evolution—9000 BC)# Less than 1 million
(ii) Agricultural Era 9000 BC–1600 AD 500 million (by 1600 AD)
(iii) Era of Industrial Revolution 1600 AD–1950 AD 1800 million (by 1900 AD)
(iv) Modern Industrial Era 1950 AD–till date 7 billion (by 2011 AD)
BC = Before Christ, AD = Anno Domini, 1 million = 10 lakhs; 1 billion = 1000 million = 100 crores
# 100,000–10,000 years ago
7.1.2 Population Explosion

Population explosion means extremely fast rise in the number of people.
Table 7.2 Population of India during 1951–2001
Year 1951 1961 1971 1981 1991 2001
Population (Millions) 361 439 548 683 846 1027
Population Explosion in Indian Context India alone has about 16% of the
world’s population. India has a population growth rate of about 2.15%. Population
growth is the reason for every environmental problem faced by Indian citizens:
(i) About one-third of the total population is poor and is subject to live below
the poverty line.
(ii) About 53% of India’s total land area is prone to soil erosion.
(iii) Forests have been declining.
(iv) Water and other natural resources are diminishing.
(v) Major population lacks basic amenities of living such as water, food, health
care, etc.
(vi) Ecosystems and biodiversity is in danger.
(vii) India is facing energy crisis.
(viii) Due to upcoming shelter needs for the growing population, agricultural land
is shrinking and leading to food crisis.
Human Population and the Environment 7.3
(ix) Population explosion has resulted in overcrowding, creation of slums, etc.

(x) Because of unemployment, rural people are migrating to urban cities; so the
government is not able to provide jobs to all.
Fig. 7.1 Consequences of population explosion
7.1.3 Population Policy

Population policy means measures instituted by a government to influence size, growth,
distribution or composition of population.
The objectives of a good population policy are the following:
(i) Proper child care.
(ii) Provide universal access to family planning and reproductive health programmes
and to information and education regarding these programmes.
(iii) Ensure that men fulfill their responsibility to ensure healthy pregnancies,
proper child care, promotion of women’s worth and dignity, etc.
(iv) Make women equal participants in all aspects of society—by increasing
women’s education, health and employment.
(v) Recognise that economic development is essential for environmental protection.
(vi) Provide information for adolescents (by increasing their access to education)
to prevent unwanted pregnancies, unsafe abortion, and the spread of AIDS
and sexually transmitted diseases.
C A M E R A EI
(i) (ii) (v) (vi) B

(iii) (iv)
Child Access to Men’s Education Recognise Adolescents
care family responsibilities of women economic informed P RC
planning development
programmes
Fig. 7.2 Objectives of population policy

To sum up, a good population policy aims at striking a balance between population
(P) and resource consumption (RC) so that biodiversity (B) and ecological integrity
(EI) is not lost.
7.1.4 Population Stabilisation

Population stabilisation means the attainment of zero growth, in which the number of
births in a population equals the number of deaths.
Population stabilisation occurs when parents have enough children to replace
them in population. In industrialised countries, a total fertility rate of 2.1 is
considered to be a replacement-level fertility needed for population stabilization.
7.1.5 Population Structure

India alone has about 16% of the world’s population which needs support from
only 2.4% of the world’s area, available in India. Population structure of a country
is given below.
Table 7.3 Population structure of a country
S.No. Population characteristics = Description
1. Population size = No. of individuals
2. Natality (birth rate) = No. of offsprings produced per female per unit
time
3. Mortality (death rate) = No. of deaths of individuals per unit time
4. Population density = No. of Individuals per unit area or volume
5. Population growth rate = Net result of births, deaths, and dispersals
6. Total fertility rate = The average number of children each woman
has over her lifetime, expressed as a yearly rate
7. Population profile = A bar graph plotting numbers of males and
(age structure) females for successive ages in the population,
ending with the oldest at the top
8. Crude Birth Rate (CBR) = The number of births per thousand of the
population per year, when consideration is not
given to what proportion of the population is
young or old, female or male.
9. Crude Death Rate (CDR) = The number of deaths per thousand of the
population per year, when consideration is not
given to what proportion of the population is
young or old, female or male.
10. Doubling time = The time it takes for a population to double
its size when population is growing at a given
growth rate
7.1.6 Population Pyramids

Age distribution influences both birth and death rates. In any ecological population,
there are mainly three age groups: Pre-reproductive (0–14 years), reproductive
(15–44 years) and post-reproductive (45 years and above). The proportion of different
age groups in any population is generally expressed graphically in the form of population
(or age) pyramids. There are three types of population pyramids.
(A) Broad-based Pyramid or Expanding-age Pyramid In a rapidly

growing population, birth rate is high, and population growth is exponential. So
each successive generation will be more numerous than the preceding one, and the
shape of the age structure is like a pyramid.
Age group Population pyramids
Post-reproductive (≥ 45 years)
Reproductive (15–44 years)
Pre-reproductive (0–14 years)
Female (%) Male (%) Female (%) Male (%) Female (%) Male (%)
(i) Expanding (ii) Stable (iii) Declining

population population population
Fig. 7.3 Age distribution and population pyramids
(B) Bell-shaped Polygon As the rate of growth of a population slows and

stabilises, the reproductive and pre-reproductive age groups become almost equal in
size while the post-reproductive group is the smallest and thus a stable age pyramid
or bell-shaped polygon is formed.
(C) Urn-shaped Pyramid If the birth rate is drastically reduced, the pre-
reproductive group decreases in proportion to the reproductive and post-reproductive
groups and thereby, an urn-shaped pyramid is formed. This type of age pyramid is
also known as a diminishing-age pyramid and it is the representation of a population
that is dying off.
7.1.7 Population Forecasting Methods
To plan services like designing a new water supply scheme and/or wastewater
treatment plant, the population needs to be calculated after a few decades so that
the scheme remains useful for the expected period. For population forecasting, data
available from a municipality-based census is used.
Important methods of population forecasting are described below:
(A) Arithmetical Increase Method This method is useful for metro cities
which have reached their saturation. This method is based on the principle that the
rate of change of population with time is constant. Future population is calculated
by using the following formula:
Px = P0 + x I
where Px is forecasted population in the ‘x’ decade
P0 is present population
x is number of decades between P0 and Px
I is average increase of population in a decade
(B) Geometric Increase Method This method is useful for developing
countries which have high population growth. This method is based on the
principle that the percentage growth rate of a population with time is constant.
Future population as per this method is calculated by using the following formula:
x
Ê r ˆ
Px = P0 Á 1 + ˜
Ë 100 ¯
r is the percentage growth rate of population
(C) Incremental Increase Method This method is useful for cities of
medium population growth. To have more accurate predictions, both arithmetic
and geometrical increase of population is taken into consideration. As per this
method, future population is calculated by using the following formula:
x ( x + 1) r ¢
Px = P0 + x I + x I +
2
I is average increment of a decade
r¢ is the average incremental rate of a decade
(D) Graphical Extension Method This method consists of the following
steps:
Step (i): Draw a growth curve between population and time using the past data.
Step (ii): Obtain shape of the curve till the present population.
Step (iii): Extend the curve till the decade of population forecasting.
example 1 Calculate the population of the world after two decades, i.e.
forecasted population in 2031 by (i) arithmetical increase method, (ii) geometrical
increase method, and (iii) incremental increase method.
Use following data for your calculations.
Year 1981 1991 2001 2011
World population (in billions) 4.5 5.3 6.2 7.3
Solution (i) Arithmetical increase method:

Year Population (in Billions) Increase in population
1981 4.5 –
1991 5.3 5.3 – 4.5 = 0.8
2001 6.2 6.2 – 5.3 = 0.9
2011 7.3 7.3 – 6.2 = 1.1
0.8 + 0.9 + 1.1
Average increase of population in a decade (I) = 0.93
3
Given present population (in 2011) = 7.3 billion = P0

2031 - 2011
\ number of decades between 2031 and 2011 = =2=x
10
Thus, population in 2031 (Px) = P0 + xI
fi Px = 7.3 + 2 ¥ 0.93 = 9.16 billions
(ii) Geometrical increase method:
Year Population (in billions) Increase in population Percentage increase in
population (r)
1981 4.5 –
0.8
1991 5.3 5.3 –4.5 = 0.8 ¥ 100 = 17.78
4.5
0.9
2001 6.2 6.2 – 5.3 = 0.9 ¥ 100 = 16.98
5.3
1.1
2011 7.3 7.3 – 6.2 = 1.1 ¥ 100 = 17.74
6.2
17.78 + 16.98 + 17.74

Percentage growth rate of population (r) = = 17.5
3
Given, present population (in 2011) = 7.3 billion = P0
2031 - 2011
Number of decades between 2031 and 2011 = 10 =2=x
x 2
Ê r ˆ Ê 17.5 ˆ
Thus, population in 2031 (Px) = P0 ÁË1 + ˜¯ = 7.3 ÁË1 + ˜ = 10.08 billions
100 100 ¯
(iii) Incremental increase method:
Year Population (in billions) Increase in population Incremental increase in population
1981 4.5 – –
1991 5.3 5.3 – 4.5 = 0.8 –
2001 6.2 6.2 – 5.3 = 0.9 0.9 – 0.8 = 0.1
2011 7.3 7.3 – 6.2 = 1.1 1.1 – 0.9 = 0.2
0.8 + 1.9 + 1.1
Average increase of population in a decade (I ) = = 0.93
3
0.1 + 0.2
Average incremental increase in population (r¢ ) = = 0.15
2
Given present population (in 2011) = 7.3 billion = P0
2031 - 2011
Number of decades between 2031 and 2011 = =2=x
10
x ( x + 1)r ¢
Thus, population in 2031 (Px) = P0 + xI +
2
2(2 + 1) ¥ 0.15
fi Px = 7.3 + 2 ¥ 0.93 + = 9.61 billions
2
7.1.8 Demographic Projections

Demography is the field of collecting, compiling, and presenting information about
populations.
Epidemiologic transition is the shift from high death rates to low death rates in
a population as a result of sanitary developments and medical advances.
Epidemiology is the study of diseases in human societies.
Fertility transition is the decline of birth rates from high levels to low levels in
a population.
Demographic transition is the tendency of a population to shift from high birth
and death rates to low birth and death rates as a result of the epidemiologic and
fertility transitions.
Demographic projections are used to represent the increase in the population.
The four stages of demographic projections are illustrated in Fig. 7.4 and discussed
below:
Fig. 7.4 Stages of demographic transition
Phase-I Population remains more or less stable as both death and birth rates are
high. The main features of this stage are backward economy where agriculture is the
main occupation, low income, poor standard of living, inadequate and unbalanced
diet, absence of educational opportunities and early marriages, etc.
Phase-II There is rapid growth of population. With the start of the developmental
process, living standards of people improve, education expands, medical and health
facilities increase; so death rates come down. But as education remains confined to a
small section of the society, and attitude of the people towards the size of the family
does not change radically, birth rates remain high. Population explosion occurs in
this phase.
Phase-III In this stage, high reduction in birth rates are observed due to
urbanisation, industrialisation, reduction in natural resources, women’s education
and use of family planning methods. Population growth is still significant.
Phase-IV High living standards, more jobs by women lead to reduction in birth
rates. Medical facilities and balanced diet lead to reduction in death rates. Thus,
Phase IV is reached, in which modern stability is achieved by a continuing low death
rate and an equally low birth rate.
The demographic transition shows that there is a correlation between development
and changing birth and death rates. It does not prove that development is necessary
for the demographic transition to occur. Present stresses on the biosphere are largely
a consequence of the consumption-oriented lifestyles of the high-income nations.
If developing countries must modernise before population growth comes under
control, their population growth, economic growth and a demand for resources and
services, will result in profound consequences. A country is said to have an optimum
population so long as the number of people is in balance with the available resources
of the country.
Case Studies
(A) India’s Population
India’s population in 1901 was about 238.4 million, which has increased by
more than four times in 110 years to reach a population of 1.2 billion in 2011.
The growth rate of population for India in the last decade was 17.60%. The
growth rate of population in rural and urban areas was 12.18% and 31.80%
respectively.
(Source: http: //censusindia.gov.in/)
India has one of the highest population growth rates in the world. In Kerala, the
population growth rate is slowing. This is because of the following initiatives:
(i) Educated Women About 50% of all Indian women are illiterate. However,
in Kerala, 85% of women are literate. Better educated women are more likely to
keep their children healthy. As children are surviving, families no longer have to
have extra children to replace those that die.
(ii) Better Status of Women Women are no longer seen as a burden. They
are regarded as an asset. When a women gets married, her family (traditionally
in India) has to pay monetary dowry to the bridegroom’s family. However, in
Kerala it is the bridegroom’s family who pays a dowry to the bride’s family.
Family welfare means are available in Kerala.
[http: //www.geography.learnontheinternet.co.uk]
(B) The Fertility Rate
The fertility rate means average number of children born per woman during her
lifetime. India had a lower estimated fertility rate than Pakistan and Bangladesh
in 2009. However, India had a higher fertility rate than China, Iran, Burma and
Sri Lanka. The fertility rate in India has been in long-term decline, and had more
than halved in the 1960–2009 period. From 5.7 in 1966, it declined to 3.3 by
1997 and 2.7 in 2009.
(C) The Replacement Rate

The replacement rate means the total fertility rate at which newborn girls would
have an average of exactly one daughter over their lifetimes. Andhra Pradesh,
Goa, Tamil Nadu, Himanchal Pradesh, Kerala, Punjab and Sikkim are seven
Indian states that have dipped below the 2.1 replacement rate level and no longer
contributing to the Indian population growth.
(Source: http// en.wikipedia.org/wiki/family.planning.in.India)
7.2 FAMILY WELFARE PROGRAMMES

Family includes children, women, men, the aged, handicapped and less privileged.
Welfare means protection from hunger, poverty, undernourishment,
underdevelopment, etc.
7.2.1 Aims of Family Welfare Programmes

Family welfare programmes aim at improving the quality of life by providing food,
shelter, education, medical and developmental assistance.
Fig. 7.5 Environmental health-risk transitions
7.2.2 Objectives of Family Welfare Programmes

The objective of the National Family Welfare Programme, launched in 1951 in
India has been to stabilise the population at a level consistent with the requirement of
the national economy by reducing the birth rate to the extent necessary.
7.2.3 Problems of Family Welfare Programmes

There is no AIM with respect to the welfare of family.
A : Awareness (poor) : (i) Inadequate awareness about family welfare
programmes, like Pulse-Polio Movement.
I : Infanticide (girl child) : (ii) Due to female infanticide, male–female sex ratio
has reached an alarming stage at the national as
well as state levels.
M : Male dominance : (iii) Due to male dominance in society, women are gen-
erally forced to adopt means of family planning.
Family Welfare Programme Jobs, safe water supply, environmental

sanitation, healthy work conditions, and smart investments in education and
healthcare are extremely effective in improving welfare of families. A focused
approach in this direction will improve productivity and economic growth.
(Partha Das Sharma, http: //saferenvironment.wordpress.com/2009)
7.3 ENVIRONMENT AND HUMAN HEALTH

Resource depletion, waste generation, distur-
bance of ecosystems, consumerism, discharge
of air or water pollutants, etc., are some of the
human activities which have continuously been
changing our environment. As a result of this,
human health has been adversely affected.
The following facts are indicators which
support that health is an outcome of the inter-
actions of humans with their environment:
(i) Due to exposure to the air pollutants re-
Fig. 7.6 Environment and
leased by industries, motor vehicles, smok-
human health
ing, etc., humans suffer from serious
respiratory diseases such as tuberculosis and lung cancer.
(ii) Due to consumption of impure water, cholera, typhoid, diarrhoea, dysentery,
etc., are caused.
(iii) Due to contamination of water through harmful pesticides, cancer, infertility
and neurological diseases are caused.
(iv) Due to scarcity of water and consequent unhygienic conditions, tuberculosis,
tetanus and leprosy are caused.
(v) Due to stagnant water, mosquitoes breed and spread malaria.
(vi) Due to high-rise buildings, visual pollution and mental strain is caused.
(vii) Due to untreated human excreta, several kinds of virus and bacteria grow
which give rise to diseases like cholera, typhoid, jaundice, diarrhoea, etc.
a Floods, heat waves, landslides, etc.

b Reduced food yields (malnutrition), etc.
c Population displacement (including slum
dwelling)
Fig. 7.7 Harmful effects of environmental change and

ecosystem impairment on human health
(viii) By direct contact with blood of infected persons or by exchange of body fluids
during sexual contact, Acquired Immune Deficiency Syndrome (AIDS) is
caused.
(ix) By consuming arsenic-contaminated water for more than 5 years, humans

develop colour change on the skin, cancer of skin, bladder, kidney, lungs
and legs.
(x) Deforestation has resulted in biodiversity loss and depleted flora and fauna.
Thus, the source of large number of medicines which are essential for
maintaining human health are badly affected.
We must work for a sustainable environment, which ultimately will result in
good health for all.
A sustainable environment and good health is achieved through
C (i) avoiding consumerism,
A (ii) anti-smoking movements and campaigns,
P (iii) population control,
T (iv) using public transport, controlling transport emissions,
A (v) afforestation and reforestation,
I (vi) preventing industrial pollution, preferred use of renewable
nonconventional energy instead of thermal power generation, and
N (vii) reduction in the consumption of natural resources, protection and
conservation of natural resources,
Case Study
Environment and Human Health
Human health is facing new challenges due to problems resulting from
environmental change. Air pollution and polluted water are shortening our lives.
In the poorest regions of the world an estimated one in five children will not live
to see their fifth birthday due to malaria, diarrhoea, etc., that are preventable.
Environmental degradation is an important factor contributing to the burden
of disease.
Environmental degradation exaggregates the imbalance between population
and resources. It worsens the severity of poverty and population health.
(Source: http://www.sercc.com/health)
7.4 FUNDAMENTAL RIGHTS

Fundamental rights are those rights which are very essential for the development,
happiness and welfare of the people.
The Indian constitution has given the following six rights to its citizens:
7.4.1 Right to Equality

Articles 14 to 18 of the Indian constitution refer to this right:
Article 14 establishes equality before law. It states the state shall not deny to any
person equality before the law.
Article 15 prohibits any sort of discrimination among the citizens on grounds of
caste, race, religion, place of birth, sex, etc.
Article 16 guarantees equality of opportunity in all fields of public employment.

Article 17 prohibits practising of untouchability in any form. This practice of
untouchability is now an offence punishable by law.
Article 18 puts an end to all titles like Khan Bahadur, Rai Sahib, etc.
Exceptions to the Right to Equality
∑ Exception for Article 15 is stated below:
“Nothing in this article shall prevent the state from making any special
provision for children and women; socially and educationally backward
classes or for the Scheduled Castes and the Scheduled Tribes.”
The above classes need special protection because most of the times they
have been victims of unequal treatment.
∑ Exception for Article 16 is stated below:
“Nothing in this article shall prevent the state from making any provision
for the reservation of appointment or posts in favour of any backward class
of citizens, which, in the opinion of the state, is not adequately represented
in the services under the state.”
7.4.2 Right to Freedom

Our constitution has guaranteed various kinds of individual and collective freedoms
to the citizens because freedom is the very essence of democracy.
The right to freedom is a cluster of the following six freedoms:
(i) Freedom of speech and expression
(ii) Freedom to assemble peacefully and without arms
(iii) Freedom to form associations or unions
(iv) Freedom to move freely throughout the territory of India
(v) Freedom to reside and settle in any part of the country of India
(vi) Freedom to practice any profession, or to carry on any occupation, trade or
business
With respect to freedom (iv) above, a restriction is laid down which states that
Indian citizens need permission to visit some border areas of the country for reasons of
security.
With respect to freedom (v) above, a restriction is laid down which states that
Outsiders are not allowed to buy property in some areas to protect the interest of the local
population.
Especially in hilly and tribal areas, the people are very poor and innocent. If rich
people are allowed to settle there, they would buy each and every piece of their land
and render them homeless in their own land. Thus, this restriction on outsiders to
buy land in certain areas is justified.
7.4.3 Cultural and Educational Rights

Indian society is very diverse. To preserve its culture, every community has been
given educational and cultural rights to preserve its culture, language and script.
Any group, sect or minority in the country can open its own educational
institutions and can teach its children accordingly. However, it has been made
obligatory on such institutions to give admission to any student desirous to join

them, irrespective of his/her religion, race, caste, sex or language. Such students
cannot be forced to learn what does not fit in their own cultural framework.
7.4.4 Right to Religious Freedom

India is a secular state. The constitution confers on the people of India the freedom
to follow any religion of their choice, to preach and practise it according to their
specific ways.
The only restriction on this right is that nothing should be done to malign or
ignite reaction among the followers of other religions.
7.4.5 Right Against Exploitation

This right saves people from any type of exploitation, It includes the following:
(i) Right Against Employment of Children Below the Age of 14 This has
been done to save children from greedy employers who exploit then in factories or
mines, etc.
(ii) Right Against Forced Labour or ‘Begar’ Earlier certain influential people
used to adopt such a practice in backward areas. However, our constitution now has
declared begar as a crime punishable by law.
7.4.6 Right to Constitutional Remedies

This is a right to secure other rights. Had this right not been there, the other rights
would have been quite meaningless.
According to this right to constitutional remedies, if any of the fundamental
rights is encroached upon by the government, the citizens can move any court. The
courts have been vested with the power to issue orders, directions and writs in order
to protect the rights of the complainants.
Chief Characteristics of the Fundamental Rights
(i) They are for each and every
citizen of the republic with-
out any consideration of reli-
gion, caste, colour or sex.
(ii) Certain restrictions are im-
posed on each of them to
safeguard encroachment by
others upon the similar rights Fig. 7.8 Fundamental rights
of one or more citizens.
(iii) In case of encroachment of our rights by a person or a group of persons, or
by the state, citizens have been given the right to knock at the doors of the
judiciary and get them redressed.
(iv) Fundamental rights have a comprehensive approach. They tend to safeguard
our social, economic, cultural and religious interests very carefully.
(v) In the interests of the safety and integrity of India, the fundamental rights of
the citizens can be suspended in the event of a national emergency.
Table 7.4 Differences between fundamental rights and human rights
Fundamental Rights Human Rights
1. Country-specific 1. Universally applicable
2. Guaranteed by constitution of a country 2. Relatively new
3. Specific and have legal sanction, and are 3. No consensus, not enforceable in
enforceable in courts courts
7.5 HUMAN RIGHTS

Human rights are the rights a person has which he or she must enjoy on this earth because
he or she is a human being.
Rights Guaranteed by the Indian Constitution (Fundamental Rights)
The rights guaranteed by the Indian constitution are called fundamental rights because
(i) these rights are quite essential for the all-round development of the citizens,
(ii) no government can abridge or abolish them, and
(iii) democratic government is not possible to run without these rights being
given to the citizens.
The United Nations General Assembly adopted the Universal Declaration of
Human Rights in1948. The declaration states that the inherent dignity of all members
of the human family is the foundation of freedom, justice and peace in the world.
With the main objective of teaching
the common language of humanity to
people and to build a universal culture
of human rights, the United Nations has
initiated efforts to promote human rights
education. It is believed that
(i) knowledge (Information about hu-
man rights and the mechanisms that exists
to protect rights) helps in development of
(ii) values, beliefs and attitudes (towards
the establishment of a peaceful and har-
Fig. 7.9 Advantages of human rights
monious society) which promotes
an (iii) action (encouraging people to defend human rights and prevent human
rights abuses).
The National Human Rights Commission (NHRC) conducts carefully designed
orientation and training programmes for the officers of police, armed forces, etc.,
to sensitise them to human rights.
Some of the important articles of the Universal Declaration of Human Rights are
summarised below:
Article 1 All human beings are born free and are equal in dignity and rights.
Article 2 Everyone is entitled to all the rights and freedoms, without distinction
of any kind, such as race, colour, sex, language, religion, political or other opinion,
national or social origin, property, birth or other status.
Article 3 Everyone has the right to life, liberty and security of person.
Article 4 No one shall be held in slavery or servitude; slavery and the slave trade
shall be prohibited in all their forms.
Article 5 No one shall be subjected to torture or to cruel, inhuman or degrading
treatment or punishment.
Article 6 Everyone has the right to recognition everywhere as a person before
the law.
Article 7 All are equal before the law and are entitled without any discrimination
to equal protection of the law.
Article 8 Everyone has the right to an effective remedy by the competent
national tribunals for acts violating the fundamental rights granted to him/her by
the constitution or by law.
Article 9 No one shall be subjected to arbitrary arrest, detention or exile.
Article 10 Everyone is entitled in full equality to a fair and public hearing by
an independent and impartial tribunal, in the determination of his/her rights and
obligations and of any criminal charge against him/her.
Article 11
∑ Everyone charged with a penal offence has the right to be presumed innocent
until proved guilty according to law in a public trial at which he/she has had
all the guarantees necessary for his/her defence.
∑ No one shall be held guilty of any panel offence on account of any act
or omission which did not constitute a penal offence, under national or
international law, at the time when it was committed. Nor shall a heavier
penalty be imposed than the one that was applicable at the time the penal
offence was committed.
Article 12 No one shall be subjected to arbitrary interference with his/her privacy,
family, home or correspondence, nor to attacks upon his/her honour and reputation.
Everyone has the right to the protection of the law against such interference or
attacks.
Article 13
∑ Everyone has the right to freedom of movement and residence within the
borders of each state.
∑ Everyone has the right to leave any country, including his/her own, and to
return to his/her country.
Article 14
∑ Everyone has the right to seek and to enjoy in other countries asylum from
persecution.
∑ This right may not be invoked in the case of prosecutions genuinely arising
from nonpolitical crimes or from acts contrary to the purposes and principles
of the UN.
Article 15
∑ Everyone has the right to a nationality.
∑ No one shall be arbitrarily deprived of his/her nationality nor denied the
right to change his/her nationality.
Article 16
∑ Men and women of full age, without any limitation due to race, nationality
or religion, have the right to marry and to found a family. They are entitled
to equal rights as to marriage, during marriage and at its dissolution.
∑ Marriage shall be entered into only with the free and full consent of the
intending spouses.
∑ The family is the natural and fundamental group unit of society and is
entitled to protection by society and the state.
Article 17
∑ Everyone has the right to own property alone as well as in association with
others.
∑ No one shall be arbitrarily deprived of his/her property.
Article 18 Everyone has the right to freedom of thought, conscience and religion;
this right includes freedom to change his/her religion or belief, and freedom, either
alone or in community with others and in public or private, to manifest his/her
religion or belief in teaching, practice, worship and observance.
Article 19 Everyone has the right to freedom of opinion and expression; this
right includes freedom to hold opinions without interference and to seek, receive
and impart information and ideas through any media and regardless of frontiers.
Article 20
∑ Everyone has the right to freedom of peaceful assembly and association.
∑ No one may be compelled to belong to an association.
Article 21
∑ Everyone has the right to take part in the government of his/her country,
directly or through freely chosen representatives.
∑ Everyone has the right of equal access to public service in his/her country.
∑ The will of the people shall be the basis of the authority of government;
this will shall be expressed in periodic and genuine elections which shall
be by universal and equal suffrage and shall be held by a secret vote or by
equivalent free voting procedures.
Article 22 Everyone, as a member of society, has the right to social security and
is entitled to realisation, through national effort and international co-operation and
in accordance with the organisation and resources of each state, of the economic,
social and cultural rights indispensable for his dignity and the free development of
his personality.
Article 23
∑ Everyone has the right to work, to free choice of employment, to just and
favourable conditions of work and to protection against unemployment.
∑ Everyone, without any discrimination, has the right to equal pay for equal
work.
∑ Everyone who works has the right to just and favourable remuneration en-
suring for himself/herself and his/her family an existence worthy of human
dignity, and supplemented, if necessary, by other means of social protection.
∑ Everyone has the right to form and to join trade unions for the protection of
his/her interests.
Article 24 Everyone has the right to rest and leisure, including reasonable
limitation of working hours and periodic holidays with pay.
Article 25
∑ Everyone has the right to a standard of living adequate for the health and
well being of himself/herself and of his/her family, including food, clothing,
housing and medical care and necessary social services, and the right to
security in the event of unemployment, sickness, disability, widowhood, old
age or other lack of livelihood in circumstances beyond his/her control.
∑ Motherhood and childhood are entitled to special care and assistance. All
children, whether born in or out of wedlock, shall enjoy the same social
protection.
Article 26
∑ Everyone has the right to education. Education shall be free, at least in
the elementary and fundamental stages. Elementary education shall be
compulsory. Technical and professional education shall be made generally
available and higher education shall be equally accessible to all on the basis
of merit.
∑ Education shall be directed to the full development of the human personality
and to the strengthening of respect for human rights and fundamental
freedoms. It shall promote understanding, tolerance and friendship among
all nations, racial or religions groups, and shall further the activities of the
UN for the maintenance of peace.
∑ Parents have a prior right to choose the kind of education that shall be given
to their children.
Article 27
∑ Everyone has the right to freely participate in the cultural life of the
community, to enjoy the arts and to share in scientific advancement and its
benefits.
∑ Everyone has the right to the protection of the moral and material interests
resulting from any scientific, literary or artistic production of which he/she
is the author.
Article 28 Everyone is entitled to a social and international order in which the
rights and freedoms set forth in this declaration can be fully realised.
Article 29 Everyone has duties to the community in which alone the free and full
development of his/her personality is possible.
∑ In the exercise of his/her rights and freedoms, everyone shall be subject
only to such limitations as are determined by law slowly for the purpose of
securing due recognition and respect for the rights and freedoms of others
and of meeting the just requirements of morality, public order and the
general welfare in a democratic society.
∑ These rights and freedoms may in no case be exercised contrary to the
purposes and the principles of UN.
Article 30 Nothing in this declaration may be interpreted as implying for any
state, group or person any right to engage in any activity or to perform any act
aimed at the destruction of any of the rights and freedoms set forth herein.
Case Study
Human Rights
Human Rights watch in its report on human rights in India during 2010 stated In-
dia had “significant human rights problems”. They identified lack of accountability
for security forces and harm for abusive policing including “police brutality, extra
judicial killings, and torture” as major problems. In 2006, the Supreme Court
ordered police reforms in response to the poor human rights record of Indian
police. The Supreme Court ordered extensive orders to implement the Right to
Food in 2001.
In India, it is possible to solve various socio-economic issues by giving human
rights to Indian citizens.
Source: http: //www.rightsined.org.nz/
http://en.wikipedia.org/wik:/human.rights.in.India
7.6 VALUE EDUCATION
7.6.1 Value
Value means ‘the ultimate worth’ of an action or a thing. For example, the
nonviolence movements of Mahatma Gandhi were of high value.
However, the misuse of power, killing of millions of persons and other such
actions of Hitler, leading to World War II have no value or have a negative value.
Thus, values are one’s own beliefs, feelings, perceptions, principles and behaviour to
judge what is right or wrong.
7.6.2 Value Education

Value education is defined as the
education that develops moral, spiritual
and cultural sense; and makes one able to
take right judgements in one’s own life.
In the context of the environment,
value education teaches us values for
nature, culture, social justice, human
heritage, equitable use of resources, and
sharing common natural resources.
It also teaches us to avoid consumer-
ism, wastefulness and overexploitation
of nonrenewable natural resources. Fig. 7.10 Benefits of value education
7.6.3 Illustrations and Examples of High and Low Values

The following examples and illustrations help us to understand high and low values.
Table 7.5 Examples and Illustrations of high values and low values
High Values Low Values
(i) Helping others (i) To be selfish
(ii) Serving older and needy people (ii) Not caring for older and needy people
(iii) Invention and practice of life-saving (iii) Invention and use of bombs and explo-
drugs sives for killing innocent people
(iv) Development of technology for curing (iv) Development of biological weapons
AIDS or cancer
(v) Use of dynamite to pave way for (v) Use of dynamite to kill innocent humans
constructing railways and roadways in and animals
hilly regions
(vi) To work for the benefit of society and (vi) To exploit nature
environment
(vii) Generating hard-earned money and (vii) Money making by unfair means
doing some charity
7.6.4 Goals and Functions of the National Resource Centre on

Value Education (NRCVE)
The goals and functions of NRCVE are
(i) To develop educational materials and other teaching aids, to document and
disseminate information
(ii) To design strategies for effective implementation
Fig. 7.11 Goals and functions of NRCVE
(iii) To develop plans, activities and programmes for value orientation of school
education
(iv) To provide extension and consultancy services
(v) To serve as a treasure house for any help
7.6.5 Objective of Value Education

The major objective of value education is to inculcate good values in individuals
and to help them lead a life as responsible future citizens of India with feelings of
universal brotherhood.
Case Study
Value Education
Seeing the acts of environmental degradation committed by humans all around
us, we are left to wonder if most humans have forgotten their responsibility to-
wards the environment.
Children learn best through the good manner exhibited by their parents/
teachers and through their ethically correct conduct. Most people are unknow-
ingly harming the environment. A lot of difference can be made by talking to
these young people who are looking for guidance and love.
Environmentally friendly behaviour will automatically develop in the society
by teaching core values like honesty, trust, respect, integrity, commitment, open
minded, individuality and equality to the youth.
[Ayesha Parveen, Shaijavalikatri.blogspot.com/2011]
7.7 HIV/AIDS
HIV stands for Human Immunodeficiency Virus. Under normal circumstances, CD4
cells (or CD4 helper lymphocyte cells: a type of defence cells in the body) help the
immune system to function normally and fight off certain kinds of infections by
acting as messengers to other immune-system cells telling them to become active
and fight against an invading germ.
A person infected with HIV is referred to as an HIV positive person. In them,
the HIV attaches to these CD4 defence cells, infects them and uses them to multiply
resulting in loss of ability of CD4 cells to do their job of fighting infections. As the
immune system becomes weak, such people are unable to fight off many infections,
particularly cancers, pneumonia, tuberculosis, meningitis, etc. The name for this
condition is Acquired Immuno Deficiency Syndrome (AIDS). In the absence of an

immune system, a minor disease may be fatal.
AIDS is one of the most destructive epidemics in recorded history. The Joint
United Nations Programme on HIV/AIDS and the World Health Organization
estimated that AIDS has killed more than 25 million people as of January 2006
since it was first recognised on December 1, 1981.
(A) Transmission of HIV The most common ways for the transmission of
HIV from one person to another are described below:
(i) From an infected mother to her baby before birth, during birth and after
birth. Breast milk can also transmit HIV infection to the infant.
(ii) HIV is mostly transmitted through semen and vaginal fluids during
unprotected sex.
(iii) Sharing of syringes and needles among intravenous drug users can transmit
HIV from an infected person to a normal person. Some nurses/doctors have
become infected after being stuck with needles containing HIV infected
blood or through splashes inside his or her nose or into their eyes.
(iv) By transfusion of blood having HIV, the virus can be transmitted to healthy
persons.
Fig. 7.12 Transmission of HIV

It is very difficult to stop the spread of HIV in India because of poverty,
illiteracy and poor health.
Fig. 7.13 Spread of HIV in India

www.icrisat.org/what.we.do/satrends/apr 2007.htm
(B) Symptoms of AIDS In a person infected with AIDS, symptoms can include
(i) Sweating at night
(ii) Swollen lymph glands
(iii) White spots in the mouth or throat
(iv) Loss of memory
(v) Consistent cough

(vi) Rapid weight loss
(vii) Extreme weakness or fatigue
(viii) Frequent long fevers
(ix) Chronic diarrhoea that lasts for more than a week
(x) Minor infections that cause skin rashes and sores in the mouth, annus or
genitals
(xi) Pneumonia
(xii) Depression and other neurological disorders
It should be remembered that each or any of the above symptoms can be related
to other illnesses. A test for HIV infection is the only way to certainly find out
whether a person has AIDS or not.
(C) Prevention of AIDS To ensure an HIV/AIDS free society, the following
awareness and proactive actions need to be implemented:
(i) Having a faithful monogamous sexual relationship with an uninfected partner
(ii) Spreading awareness, proper medical care for HIV positive pregnant women
can prevent HIV infection to the newborn.
(iii) Use of condoms (safe sex)
(iv) Transfusion of unaffected blood ensured by proper test for HIV freeness.
(v) Use of sterilised dispensable syringes
Fig. 7.14 HIV/AIDS prevention
(D) Social and Economic Impacts of AIDS Impacts of AIDS are briefly
summarised below:
(i) Millions of young people are dying every year due to AIDS. Increased
mortality of earning members results in loss of family income.
(ii) Expenditures on treating the sick, caring for AIDS orphans, training to
replace sick workers keeps on growing.
(iii) Victims of AIDS, who are still alive are unable to work. They require
special medical care. Newly trained workers have little knowledge and work
experience so the productivity reduces, increasing pressure for the state’s
finances.
(iv) Many orphans are left behind.
(v) The resources available for public expenditures (such as education) reduces.
(vi) Slower growth of economy is the result.
(vii) Social unrest in the society is the outcome.
(viii) Taxable population reduces as a result of mortalities, due to AIDS.
Impacts of AIDS
“D E F O R E S T”
Death Expenditures Finance Orphans Resource Economical Social Tax
Problems reduction loss unrest collection
reduction
Case Study
HIV/AIDS
India is one of the largest and most populated countries in the world, with over
one billion inhabitants. It is estimated that around 2.4 million people are living
with HIV/AIDS, in 2009.
HIV emerged in 1986 in India. Infection rates kept rising during the 1990s,
and today HIV affects all sectors of Indian society, not just some groups—such
as sex workers and truck drivers—with which it was originally associated.
(Source: http: //www.avert.org/acidsindia.htm)
7.8 ENVIRONMENTAL EDUCATION

Community-based environ-
mental education helps in
building knowledge and skills.
It also helps in building an
infrastructure for change that
is sustainable, equitable and
empowering. The simplified
framework is illustrated in Fig.
7.15. It shows that community
based environmental education
is capable of protecting health
and habitat from the various
problems existing in the world. Fig. 7.15 Significance of environmental education
7.8.1 Challenges
In India, the development and environmental protection challenges are enormous
due to the following reasons:
(i) Poverty It is a big challenge in reaching out to large population cost-effectively
because financial sources are very limited.
(ii) Increasing Population India’s annual population increase is equal to the
population of Australia.
(iii) Less Land With about 16% of the world population and a little over 2% of
its land, there is already enormous pressure on our resources.
(iv) Low Literacy Levels The environmental educators face many challenges to
spread awareness regarding conservation and environmental management.
(v) Low Awareness Poor Indian citizens have low or no awareness about
importance of environment.
(vi) Less Resources and Corruption Putting environmental education on the
agenda of educational decision makers and policy makers is also a big challenge
primarily because of less resources and more corruption.
(vii) No Applicability of Global Solutions The environmental educators face
difficulties in meeting the objectives of effective and local specific environmental
education because environmental conditions and environmental concerns vary from
one region of the state to another.
Fig. 7.16 Challenges for development and environment protection are weak pillars
7.8.2 Environmental Education and Its Focuses

Environmental education refers to organised efforts to teach how natural environments
function and how people can manage their behaviour and ecosystems in order to live
sustainably.
Environmental education focuses on efforts to make the world a heaven like
Kashmir is in India:
(i) Increasing people’s awareness and knowledge about the environment and
environmental challenges
(ii) Developing necessary skills and expertise to address the challenges
(iii) Fostering attitudes, motivations, and commitments to make informed deci-
sions and take responsible action for solving environment-related problems
Fig. 7.17 Focuses of environmental education
7.8.3 Role of Environmental Education for Environment Protection

Environmental education is a process of recognising values and clarifying concepts
in order to develop skills and added tools necessary to understand and appreciate the
inter-relationship among humans, their culture and their biophysical surrounding.
It is through this process of education that people can be sensitised about
environmental issues. Awareness and understanding of environmental issues help in
practicing right actions needed for development that meets the needs of the present
without compromising the ability of future generations to meet their own needs.
These concepts are illustrated in Fig. 7.18.
Fig. 7.18 Roles of environmental education for environmental protection
7.9 WOMEN’S EDUCATION

The act or process of imparting or acquiring knowledge, skill, or judgment to women is
known as women’s education.
7.9.1 Various Schemes Launched for Women’s Education in India

(i) The Sarva Shiksha Abhiyan (SSA) serves as an umbrella scheme for schemes
directly and indirectly beneficial to the girl child:
(a) The National Programme for the Education of Girls at an Elementary
Level (NPEGEL) provides free uniforms and text books.
(b) The Education Guarantee Scheme under SSA also aims to provide
vocational and nonformal education to out-of-school children, of
which, girls are the main beneficiaries.
(ii) The Kasturba Gandhi Balika Vidyalaya sets up residential schools at the
upper primary region—primarily for girls from SC, ST, and OBC families
as well as minority communities.
(iii) The Early Childhood Care and Education (ECCE) aims at setting up
preschools to prepare children for schooling. It has an indirect bearing on
education for girls as with her siblings in school, the girl child need not
assume sibling care responsibilities during school hours and can therefore,
attend school.
(iv) Mahila Samakhya (MS) Programme—It seeks to benefit women of all ages,
especially those from economically and socially marginalised groups. It aims
to integrate formal and nonformal education for girls, education schemes for
adult women and vocational training for girls and women.
(v) The Mid-Day Meal (MDM) Scheme—The presence of midday meals in the
schools
(a) increases chances for girls attending schools
(b) reduces caste biases as it forces children of all castes to eat together
(vi) The education schemes of the Ministry of Women and Child Development
(MWCD).
The Balika Samriddhi Yojana, the Integrated Child Development Services and
the Kishori Shakti Yojana are designed and funded by MWCD.
7.9.2 Obstacles in Educating Women

(i) The society dominated by males fears that its power will be taken away by
women with education.
(ii) The societies are afraid to lose their cultural identity by women’s education
and globalisation.
(iii) Poverty and scarcity of resources force the poor to send their children for work
and not to school.
(iv) Girls are trapped in a vicious downward circle of denied rights which generates
a number of problems like social unrest, high maternal mortality rates, etc.
(Fig. 7.6).
7.9.3 Advantages of Women’s Education

(i) Education provides girls and women with an understanding of basic health,
nutrition and family planning. It leads directly to better reproductive health,
improved family health, economic growth, lower rates of child mortality and
malnutrition. It is also a key in the fight against the spread of HIV and AIDS.
(ii) Educating girls and women is an important step in overcoming poverty and
raising incomes. Educated girls have better skills needed for most of the new
job categories.
(iii) Educated women are more aware of the problems in society and have ideas
on how to solve them. They contribute better to a society.
(iv) A woman with knowledge is more respectable. She has the power to make
people listen to her and the charisma that makes people follow her.
(v) An educated mother can educate the whole family.
Fig. 7.19 Obstacles in educating women and advantages of women’s education

7.9.4 Roles of Women in Environment Protection

(i) An educated woman can easily motivate other women (who are generally shy).
(ii) She can conduct different campaigns (health care, environment protection,
etc.) for local people located in the rural and urban areas. Education will
enhance awareness for the preservation of natural resources.
(iii) She can raise the interest of her family members towards education.
(iv) Only she can discuss sensitive issues like family planning and the relevant
precautionary and preventive measures needed.
(v) She is capable of attracting the attention of media, government, NGO’s, etc.,
regarding initiation of developmental activities for sustainable development
(e.g. proper waste disposal, cleanliness, tree plantation, etc.). She can mobilise
funds through voluntary donations for social activities.
Fig. 7.20 Roles of women in environment protection
Case Study
Women and Child Welfare
The World Health Organisation estimates that 1.6 billion early deaths occur
annually from cooking-stove pollution. Between 4 to 5.5 lakh children less than
5 years old, and women die each year in India due to indoor smoke.
Chula smoke is the third Time allocation
highest cause of disease and
Child care time Income Knowledge
death after dirty water and lack
of sanitation.
Over half the diseases and Child care and feeding behaviour
premature death could be avoid-
ed in India by providing access Child health and nutrition status
to clean water, sanitation, food (Source: http://llwww.seribd.com/doc)
and well-ventilated homes. Fig. 7.21 Role of mother in the welfare of child
7.10 ROLE OF INFORMATION TECHNOLOGY IN

ENVIRONMENT AND HUMAN HEALTH
7.10.1 Applications of IT in the Environment
Some of the important applications of IT in the field of environment and ecology
are listed below:
(i) Weather forecasting through Geographical Information System (GIS) for
agricultural production, water resource management, etc.
(ii) Exploring the possible availability of crude oils, gold mines, metal ores,
geothermal power sources, etc., using Remote Sensing Information System
(RSIS). Optimum selection of sites for railways or industry, etc. Biodiversity
conservation by mapping and monitoring various natural resources—flora
and fauna.
(iii) Disaster management in calamity-hit areas by extracting information.
Monitoring of environmental pollution through remote sensing.
(iv) Simulation of environmental sce-
narios for analysis, prediction, de-
cision making and development
activities. Collaboration, commu-
nication and coordination among
environmental scientists for deci-
sion-making. Fig. 7.22 IT for environment
7.10.2 Applications of IT in Human Health

Some of the applications in which IT is playing an important role for better human
health are listed below:
(i) Information on health, epidemics and their prevention is maintained on web
sites of the World Health Organization.
(ii) Through electronic media; dengue fever, bird flu and other epidemics are
brought to the attention of people.
(iii) Dates of immunisation and sanitation programmes are transmitted to public
using television, computers, satellite communication, etc. Bioinformatics is
used in the Human Genome Project (HGP) to create a map of the entire set
of genes (genome) in the human cell by decoding the three billion units of
human DNA.
(iv) Help and expert opinion can be obtained from expert doctors of any part of
the world through telemedicine.
(v) Health training is imparted using satellite communication system.
Fig. 7.23 IT for human health
Case Study
Role of Information Technology in Environment and Human Health
The world is facing many environmental problems. Humans are exploring and
discovering innovative solutions for these problems using information technology.
They are working in exploration and discovery teams and making observations,
asking questions, exploring the literature, finding inspiration, sharing data and
ideas.
Exploration
and
discovery
Gathering data
Interpreting data
Benefits Analysis
and Testing ideas and
outcomes feedback
Fig. 7.24 IT is helping in every domain of research in finding solutions

of various environment-related problems
For testing ideas, they are gathering data and are working on various hypotheses
and comparing observations and results of expected and actual findings:
(1) Supportive, (2) Contradictory, (3) Surprising, or (4) inconclusive. This is
helping them in interpreting the data to (1) support, or (2) oppose, or (3) inspire
revised/new hypothesis, or (4) inspire revised assumptions, respectively.
Testing of hypotheses and ideas is done through discussions with colleagues,
publication, replication, peer review analysis and feedback.
The above testing of ideas helps experts in coming up with new questions and/
or ideas. It also helps in theory building.
When curiosity is satisfied, knowledge is built and technology is developed,
social issues are addressed, policies are made and informed, and then everyday
problems gets solved. These are the real benefits and outcomes of the exploration
and discovery process.
(Source: http: //evolvingcomplexityii.files.wordpress.com/2009)
∑ Population is a group of organisms of a particular species, sharing a particular
characteristic of interest, most often that of living in a given area at a specific time.
∑ Population growth is the change in a population per unit time. Population growth can
be positive, static or negative.
∑ Population explosion means extremely fast rise in the number of people.
∑ Population policy means measures instituted by a government to influence size,
growth, distribution or composition of population.
∑ Population stabilisation means the attainment of zero growth, in which the number of
births in a population equals the number of deaths.
∑ The proportion of different age groups in any population is generally expressed
graphically in the form of population (or age) pyramids.
∑ Demography is the field of collecting, compiling, and presenting information about

populations.
∑ Epidemiologic transition is the shift from high death rates to low death rates in a
population as a result of sanitary developments and medical advances.
∑ Epidemiology is the study of diseases in human societies.
∑ Fertility transition is the decline of birth rates from high levels to low levels in a
population.
∑ Demographic transition is the tendency of a population to shift from high birth and
death rates to low birth and death rates as a result of the epidemiologic and fertility
transitions.
∑ Demographic projections are used to represent the increase in the population.
∑ Family includes children, women, men, the aged, handicapped and less privileged.
∑ Welfare means protection from hunger, poverty, undernourishment, underdevelop-
ment, etc.
∑ Fundamental rights are those rights which are very essential for the development,
happiness and welfare of the people.
∑ Human rights are the rights a person has which he or she must enjoy on this earth
because he or she is a human being.
∑ Values are one’s own beliefs, feelings, perceptions, principles and behaviour to judge
what is right or wrong.
∑ Value education is defined as the education that develops moral, spiritual and cultural
sense; and makes one able to take right judgements in one’s own life.
∑ The act or process of imparting or acquiring knowledge, skill, or judgment to women
is known as women’s education.
EXERCISES
Based on Population 8. Write a short note on (a) methods of
1. Enlist the different adverse effects projection of population, and (b) popu-
of population explosion. lation and food production.
2. What is population growth? How 9. Discuss the impact of population,
is it calculated? Describe the factors affluence and technology on environ-
affecting population growth. ment with suitable examples.
3. Give reasons for overpopulation 10. Define the term population explo-
and mention problems created by sion and enumerate the causes of rapid
overpopulation. population growth. Enlist the different
4. Comment on the urban problems methods of population forecasting.
related to energy and discuss the effect Based on Environmental Education
of overpopulation on energy problems 1. “Environment education can play
in India. an important role in environmental
5. (a) Explain the equation Nt = N0 ert protection”. Explain it.
(b) Enlist the assumptions of Malthusian
Based on Women’s Education
theory of maximum population.
6. Write and explain the IPAT equa- 1. Briefly describe the various schemes
tion. launched for women’s education in
India.
7. Describe in detail the environmental
factors governing human settlement.
Give effects of overpopulation.
Based on Value Education Based on the Roles of Information

1. What is meant by ‘value’ and ‘value Technology
education’? Discuss their concepts 1. Discuss the role of information
with the help of suitable illustrations. technology on human health.

I. Fill in the Blanks
3. Population (f) Attainment of zero
1. _________ is a group of organisms of
stabilisation growth.
a particular species, sharing a particular
characteristic of interest, most often 4. Demogra- (e) A field of collect-
that of living in a given area at a specific phy ing, compiling, and
time. presenting information
2. Population growth is the change in a about populations.
population per unit _________. 5. Epidemiol- (d) study of diseases in
3. Population explosion means ogy humans
________ rise in the number of people. 6. Fundamen- (c) Rights which are
4. ________ means measures institut- tal rights very essential for the
ed by a government to influence size, development, happi-
growth, distribution or composition of ness and welfare of the
population. people.
5. Population stabilisation means the
attainment of _________, in which the 7. Human (b) The rights a per-
number of births in a population equals rights son has which he or
the number of deaths. she must enjoy on this
6. _________ is a field of collecting, earth because he or
compiling, and presenting information she is a human being.
about populations. 8. Value edu- (a) The education that
7. Epidemiology is the study of cation develops the moral,
_________ in human societies. spiritual and cultural
8. _________ are the rights a person sense; and makes one
has which he or she must enjoy on this able to take right judge-
earth because he or she is a human ments in own’s own life.
being.
1. The World AIDS Day is recalled on
(a) Ist December (b) Ist January
(c) Ist February (d) Ist March
A.
2. The highest number of people with
Column I Column II HIV infection have been recorded from
1. Population (h) Change in a popula- (a) India (c) China
growth tion per unit time. (b) Africa (d) Pakistan
3. The maximum number of individuals
2. Population (g) Extremely fast rise
that can be supported by a given
explosion in the number of peo-
environment is called
ple.
(a) population size (b) Everyone has the right to own

(b) fertility rate property alone as well as in
(c) carrying capacity association with others.
(d) mortality (c) Everyone has the right to
4. The number of babies produced per education.
thousand individuals is called (d) All of the above.
(a) immigration (c) mortality 11. One’s own belief, principles,
(b) emigration (d) natality perceptions, feeling and behaviour to
5. One of the important mechanisms judge what is right and wrong is called
by which the environment controls (a) primary education
population of a species is (b) secondary education
(a) supply of food (c) value education
(b) spread of disease (d) tertiary education
(c) check on death rate 12. The threat to global environmental
(d) supply of oxygen balance and fast depletion of natural
6. Population growth in developing resources are all outcomes of
countries as compared to developed (a) pollution (b) corruption
countries is (c) government inaction
(a) slower (c) same (d) population explosion
(b) faster (d) negligible 13. Telemedicine and weather fore-
7. Equity and social justice are essential casting are examples of
components of (a) application of IT in environment
(a) fundamental rights and healthcare
(b) ethics (b) application of IT in society
(c) human rights (c) application of IT in industry
(d) human values (d) application of IT in medicine
8. Prevention of AIDS is possible 14. HIV destroys a kind of defence cells
through in the body called
(a) condom usage (a) white blood cells
(b) use of sterilised dispensable (b) CD4 helper lymphocyte cells
syringes (c) Red blood cells
(c) faithful monogamous sexual (d) nerve cells
relation 15. HIV does not spread through
(d) all of the above (a) Contaminated blood transfusion
9. AIDS stands for (b) Unprotected sex
(a) Acquired Immuno Deficiency (c) Sharing food vessels and eating
Syndrome food cooked by the infected
(b) Acquired Immunity Development person
System (d) From infected mother to her baby
(c) Acquired Insuline Deficiency
Syndrome
(d) Acquired Insuline Development
1. The more developed countries have
System
higher fertility rates. True/False
10. The human rights include the
2. The human population has increased
following:
fivefold during the last 150 years.
(a) Everyone has the right to life,
True/False
liberty and security of person.
3. The zero population growth due to 7. South Africa will be amongst the
equal birth and death rates is called most populous countries in 2050.
demographic transition. True/False True/False
4. Population explosion is world’s 8. Carrying capacity is the maximum
number one problem. True/False number that a habitat can sustain.
5. Demography is the study of trends True/False
in human population growth and pre- 9. Many environmental problems arise
diction of future growth. True/False from the abuse, misuse and overuse of
6. The world population touched the 6 natural resources by humans.
billion mark on October 12, 1999. True/False
True/False

I. Fill in the Blanks III. Multiple Choice Questions
1. Population 2. time 1. (a) 2. (b) 3. (c) 4. (d)
3. extremely fast 4. Population policy 5. (a) 6. (b) 7. (c) 8. (d)
5. zero growth 6. Demography 9. (a) 10. (d) 11. (c) 12.(d)
7. diseases 8. Human rights 13. (a) 14. (b) 15. (c)
II. Matching the terms. IV. True or False
A. 1. (h) 2. (g) 3. (f) 4. (e) 1. False 2. True 3. True 4. True
5. (d) 6. (c) 7. (b) 8. (a) 5. True 6. True 7. False 8. True
9. True
8
FIELD WORK
Learning Objectives
∑ describe the features of water resource ecosystem you have studied during
the field visit
∑ explain the aspects to be studied and the procedure for collecting
information when you want to document the environmental features and
resource assets of an ecosystem
∑ explain the methodology to be followed for study of cause and effects of a
polluted site
∑ write about any polluted site you have visited and describe your findings in
detail
8.1 INTRODUCTION
By supplementing classroom knowledge, field work can empower students with
(i) In-depth knowledge of our nature and its richness by observing real things
(ii) Leadership and cooperation capabilities
(iii) Future planning capabilities
(iv) Innovative solutions to existing problems
(v) Self-confidence
Guidelines for the Field Work GUIDELINES
The study of environment can be done precisely by 1. Planning
making timely accurate observations. An effective field 2. Preparation
study trip should consist of planning, preparation, 3. Execution
execution, follow-up, and evaluation. These simple steps 4. Follow-up
are briefly discussed below:
5. Evaluation
Step (i) Planning a Field Study Trip
Planning should be done by the student under the guidance of a teacher.
The following guidelines can be of some use:

S: Students (i) How many students need to be allowed?
P: Permission (ii) Have students taken permission from their parents?
E: Expense (iii) What will be the total expense?
N: Necessary things (iv) Are necessary things like luggages ready as per the climate con-
ditions of the place where field work has to be carried out?
D: Days (v) How many days are needed to complete the field work?
Step (ii) Getting Prepared for a Field Study Trip

Only a good teacher can clarify the purpose and importance of the field work.
When the importance or significance is known, initiative from the student side will
automatically come for the field work. This will be the right time for the teacher to
direct the students for field work.
Step (iii) Tips for Successful Execution
S: Smaller groups (i) Teacher should divide the students in smaller groups with one leader
each.
E: Execution plans (ii) The respective leaders can clarify their doubts from the teacher, if
any, and make out their respective execution plans.
A: Accomplishable (iii) Teams should cooperate among themselves, and divide total work
assignments into easily accomplishable assignments.
Step (iv) Necessity of a Well-planned Follow-up:

The collected information is converted into useful knowledge by a follow-up exercise,
which includes
M: Models (i) Preparation of charts and models.
A: Article (ii) Article writing for the magazine or for the bulletin board.
D: Discussions (iii) Class discussions.
E: Essay (iv) Essay writing.
Step (v) Getting Evaluated

F: Future (i) Evaluation helps in equipping students for a better future.
A: Appreciated (ii) During class discussions, students should be appreciated for their
right achievements during a field trip. Views should also be ex-
changed for avoiding any future discrepancies.
T: Teacher (iii) Field work should be evaluated by the teacher.
8.2 VISIT TO A LOCAL AREA TO DOCUMENT

ENVIRONMENTAL ASSETS: RIVER/FOREST/
GRASSLAND/MOUNTAIN
Students can visit a local area to document environmental assets. They should
observe the nature in its true form. They should also get feedback from local people
of that area.
Field Work 8.3
Possible Local Areas for Field Work

ã River ã Grassland ã Mountain
ã Forest ã Hill ã Pond
Guidelines for Reporting Important Information of Field Work on

Environmental Assets
(1) Area:............................................................................................................
F: Flora/Fauna (i) .....................................................................................
.....................................................................................
A: Physical details (ii) .....................................................................................
of area .....................................................................................
V: Vegetation (iii) .....................................................................................
.....................................................................................
O: Ownership (iv) .....................................................................................
.....................................................................................
U: Usage (v) .....................................................................................
.....................................................................................
R: Rainfall pattern (vi) .....................................................................................
.....................................................................................
E: Importance in (vii) .....................................................................................
ecosystem .....................................................................................
R: Role of human (viii) .....................................................................................
activities .....................................................................................
(2) Natural assets: .............................................................................................
(3) Usage of natural assets: ...............................................................................
(a) Used by.......................................................................................................
(b) Used during................................................................................................
(4) Contamination of natural assets: .................................................................
P: Pollutants (i) ................................................................................................
................................................................................................
E: Extent of Pol- (ii) ................................................................................................
lution ................................................................................................
P: Problems (iii) ................................................................................................
................................................................................................
S: Source (iv) ................................................................................................
................................................................................................
(5) Mitigation possibilities ................................................................................
∑ Best solution ..........................................................................................
(6) Lifestyle of indigenous people: sustainable or unsustainable ...................
..........................
(7) Best methodology for convincing indigenous people for the necessity of
replacement of their unsustainable lifestyle ................................................
..................................
(8) Time frame for completion of field work.....................................................

(9) Total cost....................................................................................................
(10) Achievements..............................................................................................
8.3 VISIT TO A LOCAL POLLUTED SITE–URBAN/

RURAL/INDUSTRIAL/AGRICULTURAL
Students can visit a local polluted site and report important observations.
Guidelines for Reporting Important Information of Industrially Polluted
Site
1. Name of the industry:...................................................................................
2. Capacity:....................................................................................................
3. Year of establishment:...................................................................................
4. Products manufactured:................................................................................
5. Number of workers employed:......................................................................
6. Type of wastes/emissions produced:.............................................................
7. Names of pollutants emitted:........................................................................
8. Dumping sites:...........................................................................................
9. Effluent Treatment Plant (ETP) for the treatment of industrial waste before
discharge: .....................................................................................................
10. Chimneys or stacks installed:........................................................................
11. Green belt: ...................................................................................................
12. Distance of industry from city:......................................................................
13. Health of workers:........................................................................................
14. Health impacts on people living near the industry:.....................................
15. Causes of illness
P: Thermal pollution (i) .....................................................................
U: Untreated discharge of wastes (ii) .....................................................................
N: Excessive noise (iii) .....................................................................
C: Contamination of drinking water (iv) .....................................................................
H: Hazardous pollution (v) .....................................................................
E: Emission of toxic gases (vi) .....................................................................
D: Deforestation (vii) .....................................................................
16. Impacts on environment: ...........................................................................
17. Tragedies or disaster happened in past: ......................................................
18. Best alternative technology available in world: ...........................................
19. Time consumed for this project: ................................................................
20. Achievements: ...........................................................................................
Field Work 8.5
8.4 STUDY OF COMMON PLANTS, INSECTS, BIRDS

Plants, insects and birds have tremendous potential in terms of productive, social,
ethical, ecological and consumptive value. It is worthwhile to study these species
present in our surroundings.
Guidelines for Reporting Important Information of Common Plants in
an Area
(1) Climate of area:...........................................................................................
(2) Soil type of area:..........................................................................................
(3) Type of plant (herbs/shrubs/trees):..............................................................
(4) Medicinal value of plants as per the indigenous knowledge of local people:
............
(5) Important trees which produce timber wood:..............................................
(6) Use Names of plants
(a) Gum
(b) Fibre
(c) Rubber
(d) Dye
(e) Resin
(f) Fuel
(7) Any threat from possible pollutants:............................................................
(8) Best solution:...............................................................................................
(9) Time needed for this study:.........................................................................
(10) Cost:...........................................................................................................
(11) Achievement:..............................................................................................
8.5 STUDY OF SIMPLE ECOSYSTEMS–POND,

RIVER, HILL SLOPES
“An ecosystem is defined as a natural unit that consists of living and nonliving parts
which interact to form a stable system. It is the minimal grouping of diverse organisms
that interact and function together so as to sustain life.”
Guidelines for Reporting Important Information of Ecosystems
(1) Background history:.....................................................................................
(2) Abiotic components:....................................................................................
(a) Topography:.....................................................................................
(b) Climatology:.....................................................................................
(c) Latitude:...........................................................................................
(d) Physiography:...................................................................................
(3) Biotic components:......................................................................................

(a) Producers:.........................................................................................
(b) Consumers:.......................................................................................
(c) Decomposers:....................................................................................
(4) (a) Food chains:........................................................................................
(b) Food webs:..........................................................................................
(c) Ecological pyramids:...........................................................................
(5) Biogeochemical cycle:...................................................................................
(6) Utilisation of biota by humans:...................................................................
(7) Conservation potential:................................................................................
(8) Mitigation possibilities:................................................................................
(9) Time requirement for completion of study:................................................
(10) Cost:...........................................................................................................
(11) Achievements:.............................................................................................
∑ The study of environment can be done precisely by making timely accurate
observations. An effective field study trip should consist of planning, preparation,
execution, follow-up, and evaluation.
∑ Students can visit a local area to document environmental assets. They should
observe the nature in its true form. They should also get feedback from local people
of that area.
∑ Plants, insects and birds have tremendous potential in terms of productive, social,
ethical, ecological and consumptive value. It is worthwhile to study these species
present in our surroundings.
∑ An ecosystem is defined as a natural unit that consists of living and nonliving parts
which interact to form a stable system. It is the minimal grouping of diverse organisms
that interact and function together so as to sustain life.
EXERCISES
1. (a) Explain the aspects to be studied 2. (a) What is the methodology to
and the procedure for collecting be followed for study of cause and
information when you want to effects of a polluted site? Write the
document the environmental features observations for various aspects and
and resource assets of a water resource data to be collected.
ecosystems during a field visit. (b) Write about any polluted site you
(b) Describe, in the format given above, have visited and describe your findings
the features of any such ecosystem you in detail.
have studied during a field visit.
Field Work 8.7

I. Fill in the Blanks
2. Meadows (b) A well-developed
1. _________ can empower students grass cover inters-
with in-depth knowledge of our nature persed with scattered
and its richness by observing real shrubs or small trees
things.
2. An effective field study trip should 3. Pasture (c) A land for grazing
consist of planning, preparation, cattle
execution, follow-up and _________. 4. Savanna (d) A Piece of flat
3. Only a _________ can clarify the grass land
purpose and importance of the field 5. Topogra- (e) Refer to a deep
work. phy channel worn by
4. _________ helps in equipping water.
students for better future.
5. The plants, insects and _________ III. Multiple Choice Questions
have tremendous potential in terms of 1. The aquatic ecosystem polluted by
productive, social, ethical, ecological industrial waste may
and consumptive value. (a) smell bed
6. An _________ is defined as a natural (b) has floating matter
unit that consists of living and nonliving (c) has oil on surface
parts which interact to form a stable (d) l00k fresh
system. 2. The area where solid waste is
7. _________ are small-sized plants dumped may look
with soft stems. (a) clayey and yellowish
8. _________ are medium-sized plants (b) dark and odorous
with profuse branches. (c) reddish (d) brown
9. _________ are tall with woody 3. An ecosystem that comprises of
trunks. trees, shrubs and herbs is called
10. _________ are nongreen plants, (a) desert (c) forest
which grow on other plants and obtain (b) grassland (d) pond
food from them. 4. An aquatic ecosystem whose water
is flowing is called.
II. Match the following terms. (a) lake (c) estuary
Match the terms of column I with (b) ocean (d) river
appropriate terms of column II. 5. The bird which is an indicator of
(A) human habitation is
Column I Column II (a) crow (c) koel
1. Gully (a) Refers to the sur- (b) peacock (d) parrot
face behaviour of the 6. In the grass Æ dear Æ tiger
earth such as steep- Food chain, there are
ness of slope, altitude, (a) 2 trophic levels
direction of mountain (b) 3 trophic levels
chains (c) 4 trophic levels
(d) 5 trophic levels
7. The common pollutants present in IV. Indicate True or False for the
ponds nearby agricultural fields are following statements:
(a) dust 1. For a field study trip, students are
(b) oil not required to take permission from
(c) pesticides and chemical their parents. (True/False)
fertilisers 2. Knowledge of climate conditions
(d) dyes of the place where field work has to be
8. The soil on a hill mountain site is carried out is not necessary.
characterised by the presence of (True/False)
(a) silt 3. The collected information from field
(b) sand work is converted into useful knowledge
(c) clay by a follow-up exercise (True/False)
(d) pebbles and silt 4. Evaluation of field work by their
9. Birds are known for exhibiting a teacher helps students equipping
variety of behaviours like themselves for a better future.
(a) singing (True/False)
(b) nest building 5. It is not worthwhile to study common
(c) parental care and migration plants, insects and birds present in our
(d) all of the above surroundings. (True/False)
10. The correct food chain(s) is 6. Ecosystem is the minimal grouping
(a) flower Æ butterflies Æ spiders of diverse organisms that interact and
(b) seeds Æ rodents Æ birds function together so as to sustain life.
(c) grass Æ deer Æ tiger (True/False)
(d) all of the above

I. Fill in the Blanks II. Matching the terms
1. Field work A. 1. (e) 2. (d) 3. (c) 4. (b) 5. (a)
2. evaluation
3. good teacher
4. Evaluation 1. (a) 2. (b) 3. (c) 4. (d)
5. birds 5. (a) 6. (b) 7. (c) 8. (d)
9. (d) 10. (d)
6. ecosystem
7. Herbs IV. True or False
8. Shrubs 1. False 2. False 3. True 4. True
9. Trees 5. False 6. True
10. Parasites
INDEX
A B
Abiotic components, 3.4 Balanced ecosystem, 3.3
Abiotic resources, 2.3 Balanced-diet guidelines, 2.40
Acid rain and Taj Mahal, 6.23 Bell-shaped polygon, 7.5
Acute dose, 5.43 Beneficial functions, 2.4
Acute radiation syndromes, 5.43 Beneficiary-pays principle, 6.46
Acute toxicity, 5.34 Benefits of floods, 2.31
Adsorption, 5.36 Benthic zone, 3.19
Aeration, 5.35 Bhopal tragedy, 6.45
Afforestation, 6.31 Biodiversity, 4.1
Agricultural drought, 2.32 Biogas, 2.70
Agricultural era, 7.2 Biogeochemical cycle, 2.94
Agriculture, 2.42 Biogeographic zone, 4.4
AIDS, 7.21, 7.22 Biogeographical classification, 4.4
Air (Prevention and control of Biological environment, 1.3
pollution) act, 1981, 6.36 Bio-magnification, 2.52
Air pollutant, 5.5, 6.37 Biomass, 2.70
Air pollution, 5.4 Biomass energy or bioconversion, 2.70
Animal husbandry, 6.46 Biome, 4.4
Annual deforestation rate, 2.7 Biomedical waste, 5.35
Appiko movement, 2.13 Bioremediation, 5.18, 5.40
Applications of IT in human health, Biosphere, 1.1, 1.3
7.29 Biotic components, 3.4
Applications of IT in the environment, Biotic province, 4.4
7.28 Biotic resources, 2.3
Aquatic and grassland ecosystem, 3.10 Bottled water, 5.14
Aquatic ecosystem, 3.15, 3.17
Arithmetical increase method, 7.5 C
Artificial ecosystems, 3.15 Capacity, 5.51
Atmosphere, 1.1, 1.3 Carbon credits, 6.40
Autotrophic components, 3.5 Carbon cycle, 2.95
Autotrophs, 3.5 Carbon monoxide (CO), 5.6
Carnivores, 3.6
I.2 Index
Carrying capacity, 1.12 Cradle of diversity, 4.2

Causes of deforestation, 2.5 Critically endangered, 4.5
Causes of deforestation in India, 2.6 Crude birth rate (CBR), 7.4
Causes of water crisis, 2.22 Crude death rate (CDR), 7.4
Chemoautotrophs Cultural and educational rights, 7.13
(Chemosynthesizers), 3.5 Cultural environment, 1.3
Chernobyl nuclear accident, 6.27 Cyclone, 5.64
Chipko, 2.12
Chipko movement, 2.12 D
Chronic dose, 5.44 Dam, 2.18
Chronic toxicity, 5.34 Dams—benefits and problems, 2.35
Classification of ecosystems, 3.15 Decibel (dB), 5.24
Classification of minerals, 2.37 Decomposers, 3.6
Clear felling, 2.10 Defluoridation of water, 2.29
Climate, 6.17 Deforestation, 2.5
Climate change, 6.17 Delayed somatic effects, 5.43
Clods, 2.86 Demerits of nuclear energy, 2.64
Coal, 2.61 Demographic projections, 7.8
Coal-based thermal power plants Demographic transition, 7.8
(Environmental problem), 2.62 Demography, 7.8
Coastal flood, 5.54 Desert, 3.21
Combustion, 5.50 Desert ecosystem, 3.21
Components of forest ecosystems, 3.16 Desertification, 2.89
Composting, 5.47 Destruction and removal efficiency
Compressed natural gas (CNG), 2.63 (DRE), 5.38
Conflicts over water, 2.34 Detritus food chain, 3.8
Consequences of drought, 2.32 Detrivores, 3.6
Conservation of biodiversity, 4.7 Diesel oil, 2.63
Conservation of mineral resources, Direct and indirect uses of water
2.38 resources by humans and
Conservation of natural resources, 2.90 ecosystems, 2.24
Conservation tillage, 2.43 Direct impacts, 1.5
Consumerism, 6.32 Disaster, 5.51
Consumers, 3.5 Disaster management, 5.51
Consumptive and productive values, Distillation, 5.35
4.3 Diversity, 4.1
Contour ploughing, 6.30 Double-channel or Y-shaped energy-
Control of water-related diseases, 2.28 flow model, 3.13
Conventional energy sources, 2.59 Doubling time, 7.4
Cooling ponds, 5.31 Drought, 2.32
Cooling towers, 5.31 Dry steam plants, 2.76
Corrosive substances, 5.34
Corrosive waste, 5.33 E
Cosmic radiation, 5.42 Earthquake, 5.61
Index I.3
Early childhood care and education Equitable use of resources, 2.92

(ECCE), 7.26 Equitable use of resources for
Ecological impacts, 2.15 sustainable lifestyle, 6.5
Ecological pyramid, 3.10, 3.11 Era of industrial revolution, 7.2
Ecological succession, 3.2, 6.31 Estimation of biomass, 3.13
Ecological values, 4.3 Estimation of socio-economic
Ecology, 3.1 and environmental impacts of
Economic impacts of deforestation, 2.8 deforestation, 2.9
Economic security, 1.13, 1.14 Estuaries, 3.20
Ecosystem, 3.3 Estuarine ecosystem, 3.20
Ecosystem diversity, 4.3 Eurysaline, 3.20
Effects of agriculture or environment, Eurythermal, 3.20
2.44 Eutrophication, 2.47
Effects of dams on forests, 2.19 E-waste, 5.45
Effects of dams on tribal people, 2.18 Expanding-age pyramid, 7.5
Effects of flood, 2.30 Ex-situ conservation, 4.8
Effects of pesticides, 2.49 Extinct, 4.5
Electromagnetic radiation, 2.58 Extinct in the wild, 4.5
Endangered, 4.5
Endemic species, 4.5 F
Energy, 2.57 Family, 7.10
Energy resources, 2.55 Family welfare programmes, 7.10
Energy scenario in India, 2.55 Fatman, 6.28
Environment, 1.1, 5.1, 5.2, 6.36 Fertiliser burn, 2.46
Environment (protection) act, 1986, Fertiliser number, 2.48
6.36 Fertiliser problems, 2.46
Environment and human health, 7.11 Fertiliser run-off, 2.46
Environmental degradation, 1.12 Fertilisers, 2.46
Environmental education, 1.6, 7.24 Fertility transition, 7.8
Environmental effects of extracting and Filtration, 5.35
using mineral resources, 2.38 First law of thermodynamics, 2.58,
Environmental ethics, 6.15 3.12
Environmental impacts of Flammable substances, 5.34
deforestation, 2.8 Flash flood, 5.54
Environmental impacts of mining, Flash steam plants, 2.76
2.15 Flood, 2.30, 5.54
Environmental pollution, 5.2 Flood disaster impact minimisation,
Environmental pollution process, 5.2 2.32
Environmental science, 1.6 Flood disaster management maps, 5.56
Environmental study, 1.6 Flood management, 5.55
Environmental sustainability, 6.5 Fluoride problem in drinking water,
Epicentre, 5.61 2.28
Epidemiologic transition, 7.8 Focus, 5.61
Epidemiology, 7.8 Food chain, 3.8
I.4 Index
Food security, 2.38 Hazardous wastes, 5.33

Food web, 3.8 Health impact of vehicular pollution,
Food-security resources, 2.38 5.8
Forest, 2.3, 3.16 Herbivores, 3.6
Forest (conservation) act, 1980, 6.38 Heterotrophic components, 3.5
Forest certification, 2.10 High-level wastes (HLW), 5.44
Forest degradation, 2.5 Hiroshima–Nagasaki disaster, 6.28
Forest ecosystem, 3.10, 3.16 HIV, 7.21
Forest resources, 2.3 Hot spots of biodiversity, 4.5
Fossil fuels, 2.61 Human rights, 7.15
Function of an ecosystem, 3.7 Human–environment relationship, 1.4
Functions of a forest, 2.4 Human–wildlife conflict, 4.7
Fundamental rights, 7.12 Hunter-gatherer era, 7.2
Hurricanes, 5.64
G Husk power system, 2.84
Garbage, 5.45 Hydroelectricity or hydroelectric
Gasoline or petrol, 2.63 power, 2.60
Genetic (or heritable) effects, 5.43 Hydrogen, 2.71
Genetic diversity, 4.1 Hydrological drought, 2.32
Genetic effects, 5.34 Hydrosphere, 1.1
Geometric increase method, 7.5
Geothermal energy, 2.74 I
Global warming, 6.20, 6.21 Ignitable waste, 5.33
Gobar gas, 2.70 Ill effects of deforestation, 2.5
Granivores, 3.6 Immigration, 4.2
Graphical extension method, 7.6 Impacts of over-utilisation of
Grassland ecosystem, 3.20 underground and surface water,
Grasslands, 3.20 2.23
Grazing food chain, 3.8 Impacts of timber extraction, 2.11
Green belt movement, 2.14 Importance of an ecosystem, 3.7
Green fuel, 2.70, 2.71 Importance of environmental studies,
Green revolution, 2.53 1.9
Green technology, 1.6, 1.12 Importance of minerals, 2.37
Greenhouse effect, 6.20 Importance of water, 2.22
Greenhouse gases, 6.21 Incineration, 5.38, 5.50
Guiding principles of environmental Incinerator, 5.38
studies, 1.9 Incremental increase method, 7.6
Indirect impacts, 1.5
H Indoor air pollution, 5.8
Habitat, 4.6 Industrial symbiosis, 6.40
Handlogging, 2.10 Inorganic toxic chemicals, 5.35
Hazard, 5.51 In-situ conservation, 4.8
Hazardous organic chemicals, 5.35 Instrumental values, 4.3
Hazardous waste landfill, 5.40 Intangible resources, 2.3
Index I.5
Integrated crop management, 2.44 Marasmus, 2.40

Intensive agriculture, 2.42 Marine or ocean ecosystem, 3.18
Intrinsic values, 4.3 Marine pollution, 5.20
Ion-exchange process, 5.36 Marine water body, 5.20
Ionising radiation, 2.59, 5.41 Measures used for controlling air
Issues, 6.15 pollution, 5.7
Mechanized logging, 2.11
J Medium-level wastes (MLW), 5.44
Jaitpur nuclear power project, 2.66 Mercury (Hg), 5.7
Joint forest management (JFM), 2.10 Merits of nuclear energy, 2.64
Meteorological drought, 2.32
K
Mid-day meal (MDM) scheme, 7.27
Kasturba Gandhi Balika Vidyalaya,
Mineral resource of india, 2.37
7.26
Mineral resources, 2.36
Kerosene oil, 2.63
Minerals, 2.37
Kwashiorkor, 2.41
Mining, 2.15
L Mitigation of drought impacts, 2.33
Land, 6.29 Models for energy flow in ecosystem,
Land degradation, 2.87 3.12
Land pollution, 5.17 Modern agriculture, 2.42
Land region, 4.4 Modern industrial era, 7.2
Land resources, 2.84 Mortality (Death rate), 7.4
Landfills, 5.48 Mulching, 6.30
Landslide, 2.88, 5.66 Multidisciplinary nature of
LC 50, 5.34 environmental studies, 1.7
LD 50, 5.34 Museum of diversity, 4.2
Leaching, 6.31
Lead (Pb), 5.7 N
Lineages, 4.2 Natality (Birth rate), 7.4
Liquified petroleum gas (LPG), 2.63 National resource centre on value
Lithosphere, 1.1, 1.2 education (NRCVE), 7.20
Little boy, 6.28 Natural ecosystems, 3.14
Littoral zone, 3.18 Natural gas, 2.63
Livestock, 6.46 Neritic zone, 3.19
Local extinction, 4.2 Nitrogen cycle, 2.96
Local origination, 4.2 Noise, 5.24
Logging, 2.10 Noise pollution, 5.24
Low-level wastes (LLW), 5.44 Nonconventional energy sources, 2.59
Nongovernmental organisations
M (NGOs), 6.42
Mahila Samakhya (MS) programme, Non-ionising radiation, 2.59, 5.41
7.26 Nonrenewable resources, 2.2
Major purposes of dams, 2.60 Nuclear accidents, 6.26
Malnourishment, 2.40 Nuclear energy, 2.63
I.6 Index
Nuclear fission, 2.63 Phytoremediation, 5.40

Nuclear fusion, 2.63 Plantations, 2.3
Nuclear hazard, 5.41 Poaching, 4.6, 6.44
Nuclear holocaust, 6.28 Pollutant, 5.1
Polluter-pays principle, 6.46
O Pond ecosystem (or freshwater
Objectives of conservation of ecosystem), 3.17
biodiversity, 4.8 Population, 7.1
Objectives of environmental studies, density, 7.4
1.8 explosion, 7.2
Ocean energy or marine energy, 2.73 forecasting methods, 7.5
Ocean thermal energy conversion growth, 7.1
(OTEC), 2.74 growth rate, 7.4
Old-growth or ancient forests, 2.3 in India, 2.100
Ore, 2.37 policy, 7.3
Organic farming, 2.42 profile (age structure), 7.4
Oscillating water columns (OWC), pyramids, 7.4
2.74 size, 7.4
Over-exploitations of water resources, stabilisation, 7.4
2.24 structure, 7.4
Overgrazing, 2.41 Precautionary principle, 6.45
Overnourishment, 2.41 Primary consumers, 3.6
Oxides of nitrogen (NOx), 5.7 Primary treatment, 5.13
Ozone, 6.23 Problems created by deforestation in
Ozone hole, 6.24 India, 2.7
Ozone layer, 6.24 Problems due to over-exploitation of
Ozonosphere, 6.24 energy, 2.56
Producers, 3.5
P
Public health aspects, 5.3
Peds, 2.86
Pyramid of biomass, 3.13
Pelagic zone, 3.19
Pyramid of energy flow, 3.11
Perpetual resources, 2.2
Pyramid of numbers, 3.10
Pest, 2.49
Pesticide removal methods from
Q
drinking water, 2.30
Quality aspects, 2.25
Pesticide treadmill, 2.49
Quality issues of water, 2.27
Pesticides, 2.49
Pesticides in water, 2.30 R
Pesticides: Structure and uses, 2.51 Radiation, 5.41
Petroleum, 2.62 absorbed dose (RAD), 5.43
Photoautotrophs, 3.5 pollution, 5.41
Photoperiodism, 3.7 Rainwater harvesting, 6.9
Photovoltaics, 2.68 Rare species, 4.6
Physical environment, 1.3 Reactive waste, 5.33
Index I.7
Receptor, 5.2 of dams, 2.36

Reduced-impact logging, 2.11 Socio-economic impacts, 2.15
Reforestation, 6.31 Soil, 2.85
Renewable resources, 2.2 Soil composition, 2.86
Requirements of a nonpolluted Soil erosion, 2.5, 2.89
environment, 5.2 Soil pollution, 5.17
Reserves, 2.2 Soil structure, 2.86
Resettlement and rehabilitation of Soil texture, 2.85
people, 6.13 Solar energy, 2.66
Resources, 2.2 Solar water heater, 2.69
Richter magnitude, 5.62 Solid waste, 5.45
Right against exploitation, 7.14 disposal, 5.47
Right to constitutional remedies, 7.14 management, 5.46
Right to equality, 7.12 Somatic effects, 5.34, 5.43
Right to freedom, 7.13 Sound, 5.24
Right to religious freedom, 7.14 pollution, 5.24
Risk, 5.51 pressure level (SPL), 5.25
River ecosystem, 3.20 Source, 5.1
River water pollution in India, 5.13 Sources of air pollution, 5.4
Riverine flood, 5.54 Sources of water, 2.21
Role of geothermal energy in India, Sources of water pollution, 5.9
2.76 Species diversity, 4.2
Species evenness, 4.2
S Species richness, 4.2
Salinity, 2.53 Stratosphere, 1.3
Sanitary landfills, 5.49 Strip farming, 6.30
Saprotrophs, 3.6 Structure of an ecosystem, 3.3
Sarva Shiksha Abhiyan (SSA), 7.26 Subsistence farming, 2.11
Scope of environmental studies, 1.8 Sulphur cycle, 2.98
Second law of thermodynamics, 3.12 Sulphur dioxide (SO2), 5.6
Secondary consumers, 3.6 Sustainable agriculture, 2.43
Secondary treatment, 5.13 Sustainable city, 6.6
Second-growth forests, 2.3 Sustainable development, 6.3
Seismic waves, 5.61 Sustainable forest management (SFM),
Seismometer, 5.62 2.10
Selective logging, 2.11 Sustainable lifestyle, 2.91, 6.5
Self-purification of rivers, 2.26 Sustainable mining, 2.15
Shelter security, 1.12 Sustainable urban transport, 5.28
Single-channel energy-flow model, Sustainable water management
3.12 (SWM), 2.93
Sink, 5.2
Social forestry, 2.14 T
Social security, 1.14 Tectonic earthquake, 5.61
Socio-economic and ecological impacts Terracing, 6.31
I.8 Index
Terrestrial ecosystems, 3.15 V

Terrestrial radiation, 5.42 Value, 7.19
Tertiary consumers, 3.6 Value education, 7.19, 7.20
Tertiary treatment, 5.13 Vermicomposting, 5.47
Thermal pollution, 5.29 Vulnerability, 5.51
Threatened species, 4.6 Vulnerable, 4.6
Three mile island accident, 6.27
Tidal barrage, 2.81 W
Tidal energy, 2.81 Waste to energy (WTE), 2.83
Wasteland, 6.29
Tidal stream generators (TSGs), 2.81
Wasteland reclamation, 6.29, 6.30
Tied ridges, 6.31
Waste-water treatment, 5.12
Timber, 2.10
Water (Prevention and control of
Timber extraction, 2.10
pollution) act, 1974, 6.39
methods, 2.10 Water conservation, 2.25, 6.9
Tokaimura nuclear accident, 6.27 Water cycle, 2.19
Top carnivores, 3.6 Water pollutants, 5.9
Total fertility rate, 7.4 Water pollution, 5.9, 6.39
Toxic substances, 5.34 Water resources, 2.19
Toxic waste, 5.33 Water treatment, 5.12
Trophos, 3.11 Water-borne diseases, 2.27
Troposphere, 1.3 Waterlogging, 2.53
Tsunami, 5.63 Watershed, 6.11
Types of drought, 2.32 Watershed management, 6.11
Types of energy, 2.57 Weather, 6.17
Typhoons, 5.64 Welfare, 7.10
Wildlife protection act, 1972, 6.37
U Willie-willie, 5.64
Undernourishment, 2.39 Wind, 2.78
Universal energy-flow model, 3.12 Wind energy, 2.78
Urban area, 6.7 Windmill, 2.79
Urban flood, 5.54 Women’s education, 7.26
Urbanisation, 6.7 World food problems, 2.39
Urn-shaped pyramid, 7.5 World’s water content, 2.21

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A Textbook of

Tata McGraw Hill Education Private Limited

Copyright © 2012 by Tata McGraw Hill Education Private Limited

1. Multidisciplinary Nature of Environmental Studies............................................... 1.1

� 119 Fill in the Blanks

Fig. 1.1 Concept of environment as a functional system composed

1.1.1 Composition of the Lithosphere

Fig. 1.2 Internal structure of the earth

There are two types of lithosphere.

1.1.2 The Biosphere

also contains a layer of ozone, which

1.1.3 Components of the Environment

Biological Environment Physical Environment

Fig. 1.4 Various types of environments and interactions

Fig. 1. 5 Components of the environment

1.1.4 Relationship between Humans and Environment

� Carbon dioxide for plants, air pollutants � Food/shelter/timber

With the development of human society, the human–environment relationship

1.1.5 Impact of Technology and Development on Environment

Fig. 1.7 Impact of technology and development on environment

Green Technology for Lessening the Accumulated Negative Impacts

1.2 ENVIRONMENTAL STUDIES

Fig. 1.8 Major aspects of environmental science

1.2.1 Multidisciplinary Nature of Environmental Studies

Table 1.1 Interdisciplinary nature of environmental studies—air pollution

Fig. 1.9 Many disciplines contribute to environmental science

The situation is similar in other topics of environmental studies.

1.2.2 Scope of Environmental Studies

Fig. 1.10 Scope of environmental studies

1.2.3 Objectives of Environmental Studies

(iv) acquire an attitude of concern for the environment

1.2.4 Guiding Principles of Environmental Studies

1.2.5 Importance of Environmental Studies

Fig. 1.11 A self-perpetuating vicious cycle of poverty, environmental

Fig. 1.12 Population stabilisation, poverty alleviation and environmental

1.2.6 Why is Environmental Education Provided to Engineers?

1.3 NEED FOR PUBLIC AWARENESS

1.4 ENVIRONMENTAL DEGRADATION

1.5 SHELTER SECURITY

1.5.1 Problems Faced by Homeless People

Fig. 1.14 Causes and eﬀects of environmental degradation

1.5.2 Causes of Homelessness

1.6 ECONOMIC SECURITY

1.7 SOCIAL SECURITY

(B) Positive Economic Eﬀects of Social Security

1.8 EFFECTS OF HOUSING ON ENVIRONMENT

Fig. 1.15 Housing as an environmental health issue

1.8.2 Housing and Environment

Fig. 1.16 Material ﬂows for houses

1.8.3 Strategies for Improvement of Environment

1.9 EFFECTS OF INDUSTRY ON ENVIRONMENT

1.9.1 Adverse Environmental Eﬀects of Industry

1.9.2 Approaches for Minimising Harmful Eﬀects of Industry on

OBJECTIVE TYPE QUESTIONS

Answers to Objective Type Questions

Fig. 2.1 Reserves and resources

2.2 TYPES OF NATURAL RESOURCES

2.2.1 Perpetual, Renewable and Nonrenewable

Table 2.1 Diﬀerences between perpetual, renewable and nonrenewable resources

2.2.2 Biotic and Abiotic Natural Resources