BASIC CONCEPTS :

NATURE, ECOLOGY, ENVIRONMENT

Concept
1.0 Objective
1.1 Introduction
1.2 Evolution of human being
1.3 Ecology
1.4 Environment
1.5 Types of Environment
1.6 Summary
1.7 Reference
1.8 Questions
1.0 OBJECTIVES
1) To make the students aware of the meaning of environment and its relationship with
society.
2) To familiarize the students with basic concepts namely - ecology and environment.
1.1 INTRODUCTION
Our existence, lifestyles and growth depend entirely on the sun and the earth. The energy
from the sun is called solar capital. In the same way, the planets, air, water, fertile soil,
forests, grasslands, wetlands, oceans, lakes, wildlife, minerals and natural purification and
recycling process are treated as Earth's capital. We use the term 'environment1 to describe,
in the language of G.T Miller, The Plant's fife - support system for us and for all other forms
of life'. In effect, the environment is me sum-total of solar capital and earth capital. It also
includes the thing created by humans. Environment now extends far beyond the bounds of
the local environment, thus it is the intimate enclosure of the individual or a local human
population and the global domain of the human species.
Ecology as a discipline is focused on studying the interactions between an organism of
some kind and its environment. In ecology, 'niche' refers to the role an organism or species
play in its ecosystem. An organisms niches includes everything affected by the organism
denying its lifetime. We study ecology to learn how nature works. So ecology is a study to
achieve a new goal to help scientists to develop methods to protect the natural world -
physical environment. 2
1.2 EVOLUTION OF HUMAN BEING
Man is clearly an animal. His heart, intestine, liver, lungs differ little from the corresponding
organs of cat, a dog or a monkey. His respiration, digestion, reproduction muscle
contraction, nerve or endocrine co-ordination fine the same general processes and same
general chemical and physical relations that one finds in animals. If subjected to
classification there is no difficulty in recognizing that man is a vertebrate and hence belongs
to the phyllum chordata. Among the vertebrates he obviously belong with the class of
mammals. He is bipedal using only his hand legs for locomotion but this is also true of
Kangaroos. Men, monkeys and apes are very similar to the anatomy. Ecologist concerned
with the study of various eco-systems regard man chiefly as a disturbing element in it, and it
is this growing attitude on the growing reality of man's disturbing tendency that has given
rise to the academic interest in man-nature relations. When Darwin published the Descant
of Man (1871) he did not know of any human fossils. He built his case for human evolution
entirely on evidence from living men and living primates, and he thought the great break in
the Organic chain between apes and man might never be bridged because of the imperfect
nature of the fossil record. !n late 1920s and early 1930s a series of man-like fossils were
found in a cave deposit near Choukoution in China, 42 miles from Peking (Bejing). These
very the remains of what came to be called as the Peking man or Sinanthropus. In
subsequent years a variety of homonid fossils were discovered mostly in Africa. These do
not form a neat chin of links leading from ancient ape to modern man. They cannot be
arranged in a single sequence and it appears that a considerable variety of man-like
animals lived a different times and places in the pleistocene. The Pleistocene was short as
geological periods go, and it was also peculiar in having great four waves of glaciation
around their way much across North America and Europe, and particular events are dated
with reference to these glacial and interglacial periods, although absolute time range
remains uncertain.
1.3 ECOLOGY
The word ecology derived from the Greek word 'Oikos meaning habitation, and logos
meaning discourse or study, implies a study of the habitations of organisms. Ecology was
first described as a sepearate field of knowledge in 1866 by the German Zoologist Ernst
Haeckel, who invented the word Ecology for 'the relation of the animal to its organic as well
as its inorganic environment, 3
particularly its friendly or hoslite relations to those animals or plants with which it comes in
contact. Ecology has been variously defined by other investigators as "Scientific natural
history", "the study of biotic communities, or "the science of community population",
probably the most comprehensive definition is the simple one most offers given' a study of
animal and plants in their relations to eachother and to their environment. Ecology may be
studied with particular reference to animals or to plants, hence animal ecology an plant
ecology. Animal ecology, however, cannot be adequately understood except against a
considerable background of plant ecology. What animal and plants are given equal
emphasis, the term bioecology is often used. Causes is plant ecology usually dismiss
animals as but one of many factors in the environment. Synecology is the study of
communities, and autecology the study of species. There is some confusion in these terms
since Europeans commonly use 'ecology' in manover sense - meaning the environmental
relations of organisms or of communities. The broader study of communities, including
species interrelations and community structure and function as well as environmental
relations (Synecology), is generally ermed bioecology or "biosociology" by Europeans.
1.5 ENVIRONMENT
Its meaning and significance History reveals that human race was once afraid of nature
and the natural forces. Human beings worshiped nature and considered nature as superior
to human race. Enormous increase in human population raised the demand for
development and increased the consumption of variousnatural resources resulting in
environmental deterioration. The term environment describes the sum total of physical and
biotic conditions influencing the responses organisms. More specifically, the sum of those
portions of the hydrosphere, lithosphere, and atmosphere into which life penetrates is the
biosphere. There are no characterstics of permanent inhabitants of the atmosphere,
although the air is traversed by manly kinds of animals and plant propagules. Of the
hydrosphere, there are two major bicycles, marine and fresh water, of the tithosphere there
is one land.
A-habitat is a specific set of physical and chemical conditions (for example, space,
substratum, climate) that surrounds a single species, a group of species or a large
community. The ultimate division of the biosphere is microhabitat, the most intimately local
and immediately set of conditions surrounding an organism, the burrow of a rodent, for
instance, or a decaying log. Other individuals 4
or species are considered as a part of the community to which the organisms belong and
not part of its habitat. The term biotope defines a spatial or topographic unit with a
characterstic set both of physical and chemical conditions and of plant and animal life. In
order for organisms to exist they must respond or adjust to the conditions of their
environment. The first living organisms probably evolved in the sea and must have
possessed very generalised adjustments to this relatively uniform and favourable habitat.
However, these early organisms are inherent in them the potential for expansion, as they
later spread into other and more rigorous habitats, particularly fresh water and land. As
evolution proceeded, organisms became more and more limited in the range of their ability
to respond as they became specialised in their adjustment to particular habitants. This led
to the great diversification of species that we see at the present time, with each species
restricted to its particular microhabitat and place in the community.
1.5 TYPES OF ENVIRONMENT
Environment can be classified into 3 broad types a) Biotic (living) -
The word biotic refers to having to do with living organisms. Biotic elements refer to the
biological component of the ecosystem, consisting of population of plants, animals and
micro organisms in complex communities. The biotic factors influencing an organisms,
viruses and other parasytic organisms cause diseases. There are all parts of an organisms
biotic environment. The biotic component of the ecosystem consists of 3 distinct groups of
organism, the producers, consumers and decomposers. The producers are those
organisms capable of photosynthesis, production of organic material solely from solar lift
and carbondioxide. This organic material serves as a source of both energy and mineral
nutrients. Both are required by all living organisms. Examples include both terresticial and
acquatic plants such as phytoplankton. The consumers are organisms whose very survival
depends on the organic material manufactured by the producers. The consumer represent
animals of all sizes ranging from large predators to small parasites, such as mosquitoes and
flies. The nature of the consumers dependence on the producers takes various forms.
Some consumers (herbivores such as rabbits) are directly dependent on primary producers
of for energy. Others (carnivores such as tigers)depend indirectly on primary producers.
The last group of living organisms is the decomposers. These include micro-organisms
such as fungi, bacteria, yeast etc. as well as a diversity of worms, insects and many other
small animals. They all rely on dead organisms for their existence and survival. In their
efforts to survive and obtain energy they decompose materials released by plants and
consumers to their original elements (C,O,H,N,S,P). This 5
is what keeps material cycling within the ecosystem. The biotic community together with the
physical environment forms are interacting system called ecosystem. b) Abiotic - Abiotic
factors* include the flow of energy necessary to maintain any organism, the physical factor
that affect it and the supply of molecules required for its life functions. Other physical factors
include climate, temperature, preciptation, including its types (rain, snow, hill) around and
seasonable distribution, types of soil present (sandy or clay, dry or wet, fertile or infertile).
All forms of life require atoms such as carbon, nitrogen and phosphorous and molecules
such as water to construct and maintain themselves. The organisms constantly obtain these
materials from environmental by eating food or taking them us through the process of
photosynthesis. In the ecosystem, the abiotic (non-living) \components perform 3 important
function water and oxygen for organisms. 2nd, they act as a reservoir of the 6 most
important elements for life, carbon(C), hydrogen(H), Oxygen (O), nitrogen (N), Sulphor (S)
and phosphorus (P). These elements constitute 95% of all living organisms. 3rd, the Earth
contains only a fixed amount of these elements. Thus continual functioning of the
ecosystem requires one thing at least. These elements have to be recycled because they
are critical to the welfare of the ecosystem as a whole. c) Cultural - The stage of
development that human being have attained in the path towards progress will determine
their culture as way of life. Human interaction with environment also influence the
ecosystem. People of different cultures view their place in society from different angles.
Among the factors that can shape their views are religious understandings, economic
pressures and fundamental knowledge of nature. Due to this diversity of background
different cultures put different values on the natural world. But the general attitude has been
one of development rather than preservation. Technology has been the key to human
progress. Technology has also increased the quantity of environmental degradation. Human
interaction with the environment has increased very fast of late. For example, the green
house effect is thought to result from energy consumption, agricultural practices and
climatic change. It is now felt that we have entered an era characterised by global change
that arises from the interdependence between human development and their environment.
So self conscious and intelligent management of the earth is one of the greatest challenges
facing humanity today. Human also cause extinction lin indirect ways. The building of dams
changes the character of rivers, making them less suitable for some species. 6
1.5 SUMMARY
Nature and environment are commonly used terms for the ecology. Man is seen as a sort of
geoglogical force reshaping landscape, favouring some kinds of organisms and destroying
others, changing the very composition of the atmosphere and starting new chain of radio
activity with atomic explosions.
1.6 REFERENCE 1) Marston Bates 1961, Man in nature, Practice Hall New Jersey. 2)
Ruth Moere 1975, Man in Environment, Tata McGraw Hill, New Delhi 3) Gibson A 1866 : A
Hand Book of Forests 1875-1860 Bombay Government District Gazetleer North Kanara
Bombay 4) Tiwari PR, Raj G 1992, Environmental Ecology Akashdeep Publishing Home
Delhi. 5) Thirmurthy A.M. 2004, Principles of Environmental Science, Engineering and
Management, Shroff Publishers Mumbai.
1.7 QUESTION
Q.1. Define environment and ecology? Q.2. What do you know about the ecology and types of
environment?