1

Unit 2
Ecosystem

Concept of Ecosystem

Ecosystem Definition
“An ecosystem is defined as a community of lifeforms in concurrence with non-living components,
interacting with each other.”

What is an Ecosystem?
An ecosystem is a structural and functional unit of ecology where the living organisms interact with each other
and the surrounding environment. In other words, an ecosystem is a chain of interactions between organisms
and their environment.
The term “Ecosystem” was first coined by A.G.Tansley, an English botanist, in 1935.

As a group of living organisms living in a specific environment and interacting, an ecosystem can be defined
as a community or group of organisms.

The tropical forest, for instance, is an ecosystem consisting of trees, plants, animals, insects and
microorganisms that are in constant contact withoneanother and that are affected by other physical and
chemical components (such as sunshine and temperature).

Ecologyisthestudyofnaturefromtheperspectiveofanecosystem.Anecosystemisdefinedhereasadefinedphysical
environment,consistingoftwo inseparable components:

Thebiotope(abiotic)-
aparticularhabitatwithspecialphysicalfeaturessuchastemperature,humidity,nutrientconcentration,pH,
climate, etc.

The biocenosis (biotic) - An organism or a set of organisms that continuously interact with and are
interdependent. Examples includeanimals, plants, and microorganisms.

Ecosystem Degradation

Introduction
An ecosystem is a collection of plants, animals and other living organisms that share the space and benefits of
an environment.

1
Notes By Prof. Sonali Mangam-Panekar Contact No: +91-9960730903
Renaissance Institute of Management Studies, Chandrapur
In an ecosystem, every organism comes with a specified role and function. Thus disturbing the balance of an
ecosystem will prove to be disastrous for every living thing that relies upon it.
It can be said that the Earth is an ecosystem on a much gigantic scale. When external factors such as pollution
through carbon dioxide and methane, the balance of the ecosystem is disturbed to such an extent that it will
affect everyone living in it.
Some of these disturbances are what cause natural disasters such as earthquakes, tsunamis etc.

What are the causes of ecosystem degradation?

When an ecosystem is stable and healthy, it is called a sustainable environment. This means that it is capable
of sustaining itself and reproducing. Sustainable ecosystems have biodiversity. There’s a variety of species and
organisms living there and contributing. The causes that will destroy such an environment are given below:

1. Ecosystem destruction is already happening at an alarming rate. As per a research study published by
Forbes in February 2020, over the next 20 years, scientists estimate about 70% to 90% of all coral reefs
will disappear. This is due to warming ocean waters, ocean acidity, and pollution.
2. Deforestation is caused by Illegal logging and human need and progress. As per the Food and
Agriculture Organization (FAO), “Between 2015 and 2020, the rate of deforestation was estimated at
10 million hectares per year, down from 16 million hectares per year in the 1990s. The area of primary
forest worldwide has decreased by over 80 million hectares since 1990.”
3. As per WWF’s Living Planet Report 2020, 1 million species (10 lakhs animals, plants and insects) are
threatened with extinction.
4. Habitat loss is endangering our animal species. Apex predators such as the lion, tiger leopard and even
the majestic mountain gorillas are all being threatened by habitat loss.
5. Humans destroy ecosystems. The lifestyle of the human species is quite self-destructive, to say the
least as it creates pollution along with the criminal overuse of natural resources. Construction of
infrastructure like roads, hunting of animals, clearing the planet of trees are just some of the factors
accelerating the destruction of the ecosystem. At the rate at which resources are being consumed,
there may not be any left for future generations.

What will be the impact of ecosystem degradation?

The impact of ecosystem destruction are the following:

 Increased flooding due to the erosion of soil and lack of trees.

 Climate change causes the sea levels rising due to the melting of the glaciers.
 More a likelihood that natural disasters such as tsunamis, earthquakes, droughts will be commonplace.
 Disruption of the food chain when the apex predators become extinct.
 Water shortage – the supply of fresh drinking water is limited with only a few water bodies being fit for
human consumption.

__________________________________________
2
Notes By Prof. SonaliMangam-Panekar Contact No: +91-9960730903
Renaissance Institute of Management Studies, Chandrapur
  Food shortage as the lands become barren and the oceans become devoid of fish and other marine life
 Loss of biodiversity as a whole species of living things disappear due to deforestation

What will be the ultimate impact of ecosystem destruction?

It is with no exaggeration that it can be said that the earth is heading for destruction. But efforts are being
made to address these global concerns. People are becoming more aware that the little things that they do
every day do have an effect – whether negatively or positively is up to discretion.
Every aspect of our ecosystem is important – because when one goes, the rest will follow.
Imagine this scenario… When the global temperature continues to rise, the glaciers will melt. The sea levels
will rise and coastal cities will be inundated, killing millions of people. Economies will stop and will be severely
burdened in trying to sustain everyone. Farms will be flooded, there will be no food.
It goes on and none of it is a pretty picture. So while we still can, let’s do our share to stop degrading our
ecosystems. Our lives depend on all of us interacting in a sustainable environment.

Structure of the Ecosystem

2
The structure of an ecosystem is characterised by the organisation of both biotic and abiotic components.
This includes the distribution of energy in our environment. It also includes the climatic conditions prevailing
in that particular environment.
The structure of an ecosystem can be split into two main components, namely:

 Biotic Components
 Abiotic Components

The biotic and abiotic components are interrelated in an ecosystem. It is an open system where the energy
and components can flow throughout the boundaries.

3
Notes By Prof. SonaliMangam-Panekar Contact No: +91-9960730903
Renaissance Institute of Management Studies, Chandrapur
Biotic Components
Biotic components refer to all living components in an ecosystem. Based on nutrition, biotic components can
be categorised into autotrophs, heterotrophs and saprotrophs (or decomposers).

1. Producers include all autotrophs such as plants. They are called autotrophs as they can produce food
through the process of photosynthesis. Consequently, all other organisms higher up on the food chain
rely on producers for food.
2. Consumers or heterotrophs are organisms that depend on other organisms for food. Consumers are
further classified into primary consumers, secondary consumers and tertiary consumers.

3
a. Primary consumers are always herbivores as they rely on producers for food.

b. Secondary consumers depend on primary consumers for energy. They can either be carnivores or
omnivores.

c. Tertiary consumers are organisms that depend on secondary consumers for food. Tertiary consumers
can also be carnivores or omnivores.

d. Quaternary consumers are present in some food chains. These organisms prey on tertiary
consumers for energy. Furthermore, they are usually at the top of a food chain as they have no natural
predators.

3. Decomposers include saprophytes such as fungi and bacteria. They directly thrive on the dead and
decaying organic matter. Decomposers are essential for the ecosystem as they help in recycling
nutrients to be reused by plants.

4
Notes By Prof. SonaliMangam-Panekar Contact No: +91-9960730903
Renaissance Institute of Management Studies, Chandrapur
Abiotic Components
Abiotic components are the non-living component of an ecosystem. It includes air, water, soil, minerals,
sunlight, temperature, nutrients, wind, altitude, turbidity, etc.

Functions of Ecosystem
The functions of the ecosystem are as follows:
1. It regulates the essential ecological processes, supports life systems and renders stability.
2. It is also responsible for the cycling of nutrients between biotic and abiotic components.
3. It maintains a balance among the various trophic levels in the ecosystem.
4. It cycles the minerals through the biosphere.
5. The abiotic components help in the synthesis of organic components that involve the exchange
of energy.

The functional units of an ecosystem

Productivity – It refers to the rate of biomass production.

4
Energy flow – It is the sequential process through which energy flows from one trophic level to another. The
energy captured from the sun flows from producers to consumers and then to decomposers and finally back
to the environment.

Decomposition – It is the process of breakdown of dead organic material. The top-soil is the major site for
decomposition.

Nutrient cycling – In an ecosystem nutrients are consumed and recycled back in various forms for the
utilisation by various organisms.

Ecological Succession
What is Ecological Succession?

5
Notes By Prof. SonaliMangam-Panekar Contact No: +91-9960730903
Renaissance Institute of Management Studies, Chandrapur
The gradual and progressive growth of a species in any given area with respect to its changing surroundings is
called an ecological succession. It is an anticipated change that beholds the biotic components being an
inevitable part of them in the environment. Ecological succession aims at reaching the equilibrium in the
ecological system. This is achieved by a community called the climax community. To attain this point of
equilibrium constant change (increase or decrease) in the number of species is observed. The area in which
the order of communities undergoes a specific change is called sere. Each changing community is therefore
called a seral community. All communities around us have undergone ecological succession ever since their
existence was identified. Evolution thus is a simultaneously occurring process along with ecological
succession. Also, the initiation of life on earth can be considered to be a result of this succession process.

Any area where life started from scratch by succession is termed to have been gone under a process called
primary succession. If on the other hand, if life begins at a place that has lost all its existing life forms then the
process is called secondary succession. Primary succession is a gradual and low process because in this case,
life starts from nothing. Secondary succession is a faster process because life has already been supported in
these conditions earlier. The first species that come into existence during primary succession is known as
pioneer species.

Types of Ecological Succession

As mentioned above primary and secondary succession are the two main types of ecological succession. The
following stages of ecological succession are discussed below:

Primary Succession
Primary succession is the succession that begins in lifeless areas such as the regions devoid of soil or barren
lands where the soil is unable to sustain life. When the planet was first formed there was no soil on earth. The
earth was only made up of rocks. These rocks were broken down by microorganisms and eroded to form soil.
This is a process called erosion. The soil then becomes the foundation of plant life. These plants help in the
persistence of different animals and progress from primary succession to the climax community. When the
primary ecosystem is destroyed, secondary succession takes place.

Secondary Succession
Secondary succession occurs when the primary ecosystem gets wiped out. For e.g., a climax community gets
destroyed by fire. It gets recolonized after the devastation. This is known as secondary ecological succession.
Small plants emerge first, followed by larger plants. The tall trees block the sunlight and change the structure
of the organisms below the canopy. Finally, the climax community comes into action.

What is Seral Community?

“A seral community is a transitional stage of ecological succession progressing in the direction of the climax
community.” A sere, or seral community, is described as the progression of an ecological community's growth
\

phases from the pioneers to the climax. A climax community in the ecological community wherein the
populations are stable and coexist in harmony with one another and their surroundings is defined as the last
stage of succession, and it remains basically intact until it is destroyed by a natural disaster or human
intervention. Seral community is substituted by the succeeding community. It consists of simple food webs
and food chains. It exhibits a very low degree of diversity. The individuals are less in number and the nutrients
are also less.

Types of Seres
There are seven different types of seres, these are mentioned below in the table below along with their
meaning.

Types of Seres Explanation

Hydrosere Succession in an aquatic habitat.

Xerosere Succession in a dry habitat.

Lithosere Succession on a bare rock surface.

Psammosere Succession initiating on sandy regions.

Halosere Succession starts in saline soil or water.

 Senile The succession of microorganisms on dead matter.

Ecosphere Development of vegetation in an era.

Examples of Ecological Succession

Following are the important examples of ecological succession:
Acadia National Park
This national park faced a dreading wildfire. Restoration of the forest was left on to Mother Nature. In the
initial years, only small plants grew on the charred soil. After several years, the forest showed diversity in tree
species. However, the trees before the fire were mostly evergreen, while the trees that grew after the fire
turned out to be deciduous in nature.

Causes of Ecological Succession

Some important causes may be defined as below:

 Climatic Causes: these can be rainfall, temperature variations, humidity, gas composition, etc.

 Biotic Causes: the organisms in a community compete to thrive for existence. Some of them are lost in the
process while some new ones are incorporated.

 External Causes: soil conditions are affected by the process of migration, invasion, and competition amongst
various species.

Characteristics of Ecological Succession

Ecological succession has subsequent characteristics:

 It results from the disparity in the physical atmosphere of the community.

 It is a systematic procedure of community development.

 It involves variations in species structure and it increases the diversity of species.

 Nutrient variation regulates the settlement of new communities.

 Succession operates in a stabilized ecosystem.

Mechanism of Ecological Succession

The entire process of primary succession is accomplished through a series of progressive steps followed one
after another. The different sequential steps may be outlined as below:

___________________________
8
Notes By Prof. SonaliMangam-Panekar Contact No: +91-9960730903
Renaissance Institute of Management Studies, Chandrapur

Nudation:
 It is a process of formation of a bare area without any form of life for the arrival of new species. The causes of
nudation may be:

Topographic: E
The existing community may fade away due to soil erosion, landslide, volcanic activity, etc.

 Climatic: The existing community may be demolished due to storm, fire, frost, drought.

 Biotic: The community may also be destroyed by anthropogenic activities like the destruction of the forest,
the destruction of grassland, etc.

Invasion:
The successful establishment of a species in a vacant area is called invasion. This process of establishment is
completed in three successive steps:

 Migration (dispersal): The seeds, spores of the species are carried to the unadorned area by the agents like
air, water, etc.

 Establishment: The process of the successful establishment (germination and growth) of the species in the
new area as a result of adjustment with the prevailing conditions is known as eccyesis.

 Aggregation: After eccyesis, the individuals of species increase their number by reproduction and thus, are
aggregated in a particular area.

Competition and Coaction:

As the species aggregate within a restricted space, there happens competition for space and nutrition.
Secondly, the life process of one individual is affected by the surrounding species in various ways which are
known as coaction.

Reaction:
The species present in an environment constantly interact with it by causing its modification. The mechanism
of the modification of the environment through the influence of living organisms on it is known as a reaction.
Hence, the existing community may be replaced by another community.

Stabilization:
At last, a final or terminal community is established which can maintain equilibrium. This community is known
as the climax community.

___________________________________
9
Notes By Prof. SonaliMangam-Panekar Contact No: +91-9960730903
Renaissance Institute of Management Studies, Chandrapur
All processes in this world, whether living or non-living, need energy. Living organisms are capable of
producing energy or getting it through predation. They need this energy to maintain cells and tissues. It is also
required for supporting voluntary and involuntary actions of the human body and other multiple processes
within the body like reproduction, cell division, metabolism, digestion, circulation, excretion, and much more.
The ultimate source of energy on Earth is the Sun. No energy can be produced without the sun. All living
beings, especially plants capture solar energy and utilise it for their food production. This process is called
photosynthesis.

What is Food Web?

There are unique interactions and relationships which are involved in the transportation of energy. The
energy, once produced and captured, is distributed throughout the various living organisms. This transfer of
energy is termed as the food web.

What is the Food Chain?

A food chain is a network of links in a food web. Here, the producers are consumed by the predators-primary
and secondary consumers and then the detritivores and finally by decomposers. When many such individual
food chains occur in an ecosystem, it is known as Food Web.
A food chain shows a direct transfer of energy between organisms. As every organism can feed on multiple
things, a food web is a much more realistic and simplified method of transferring energy in an ecosystem.

A food chain presents a unique, connected path of energy flow in an ecosystem, whereas the food web
explains how food chains overlap. Both food chains and food webs, shares three types of organisms in a food
chain: producers, consumers and decomposers.

Producers
Organisms that can synthesize their own food and usually serve as the foundation for all food chains. For
example – plants, algae and few species of bacteria. They prepare their own food by converting sunlight into
chemical energy and this process is called photosynthesis. They use energy from the sunlight for converting
carbon dioxide into simple glucose which is easily broken down to produce energy. This energy is then stored
in the form of sugars for later use.

Primary Consumers
They are also called herbivores animals who eat producers or plants. Sometimes, these primary consumers
become prey for other animals that sit higher on the food chain. Some of the primary consumers or herbivores
living on the land are chipmunks, mice, horses, birds, deer and some insects. Fish, zooplankton, snails, sea
urchins are a few marine primary consumers.
__________________________________
10
Notes By Prof. SonaliMangam-Panekar Contact No: +91-9960730903
Renaissance Institute of Management Studies, Chandrapur

10 Percent Energy Rule

Even though primary consumers feed on producers, they are still getting their energy from the sun. The
primary consumers feed on plants and break down the food particles to release the energy.
Primary consumers do not get 100% of the sun’s energy from the producers or the plants on which they feed.
This is because only some amount of the sun’s energy is utilised by the plant to synthesise their food.
In fact, they only get 10% of the energy. This is termed as the 10% Rule, which states that only 10 per cent of
the energy available gets passed onto the next level of consumers.

Secondary Consumers
These are animals who feed on primary consumers. They usually eat meat and are termed as predators. Lion,
hawks, snakes, coyotes, wolves, and spiders are a few terrestrial secondary consumers.

Tertiary Consumers
They are the ones who feed on secondary consumers. They are thus called the top predators. They are also
termed as apex predators and have no natural enemies. Naturally, you would assume that humans are at the
top of the food chain, but they are not.

Why are Humans not at the top of the food chain?

Scientists categorize the organisms on the food chain by trophic levels. A “Trophic level” means how far an
organism is from the start (level 1) of the food chain.
5
Predators that use a top-down control on organisms in their community are often considered keystone
species. Humans are not considered apex predators because their diets are typically different, although
human trophic levels increase with the consumption of meat.
For instance, plants are considered to be at trophic level 1, and the apex predators are usually placed at level 4
or 5. According to scientists, humans are placed on a trophic level of 2.21

Types of Ecosystem
An ecosystem can be as small as an oasis in a desert, or as big as an ocean, spanning thousands of miles. There
are two types of ecosystem:

 Terrestrial Ecosystem
 Aquatic Ecosystem

Terrestrial Ecosystem
Terrestrial ecosystems are exclusively land-based ecosystems. There are different types of terrestrial
ecosystems distributed around various geological zones. They are as follows:

1. Forest Ecosystem
2. Grassland Ecosystem
3. Tundra Ecosystem
4. Desert Ecosystem

Forest Ecosystem
11
Notes By Prof. SonaliMangam-Panekar Contact No: +91-9960730903
Renaissance Institute of Management Studies, Chandrapur
A forest ecosystem consists of several plants, particularly trees, animals and microorganisms that live in
coordination with the abiotic factors of the environment. Forests help in maintaining the temperature of the
earth and are the major carbon sink.
Grassland Ecosystem
In a grassland ecosystem, the vegetation is dominated by grasses and herbs. Temperate grasslands and
tropical or savanna grasslands are examples of grassland ecosystems.
Tundra Ecosystem
Tundra ecosystems are devoid of trees and are found in cold climates or where rainfall is scarce. These are
covered with snow for most of the year. Tundra type of ecosystem is found in the Arctic or mountain tops.
Desert Ecosystem
Deserts are found throughout the world. These are regions with little rainfall and scarce vegetation. The days
are hot, and the nights are cold.

6
Aquatic Ecosystem
Aquatic ecosystems are ecosystems present in a body of water. These can be further divided into two types,
namely:

1. Freshwater Ecosystem
2. Marine Ecosystem

Freshwater Ecosystem
The freshwater ecosystem is an aquatic ecosystem that includes lakes, ponds, rivers, streams and wetlands.
These have no salt content in contrast with the marine ecosystem.
Marine Ecosystem
The marine ecosystem includes seas and oceans. These have a more substantial salt content and greater
biodiversity in comparison to the freshwater ecosystem.

Structure and Function of Forest Ecosystem

I. Biotic components:

The various biotic components, representatives from the three functional groups, of a forest ecosystem are:

1.Producer Organisms:

1. In a forest, the producers are mainly trees.

2. Trees are of different kinds depending upon the type of forest developed in that climate.
3. Apart from trees, climbers, epiphytes, shrubs and ground vegetation.
4. Dominant species of trees in major types of forest ecosystems are:

12
Notes By Prof. SonaliMangam-Panekar Contact No: +91-9960730903
Renaissance Institute of Management Studies, Chandrapur
5. Tectonagrandis, Acer, Beulah, Picea, Pine, Cedrus.

2. Consumers: In a forest, consumers are of three main types.

a.Primary Consumers:

1. These are Herbivores which feed directly on producers.

7
2. Ants, Beetles, Bugs, spiders etc. feeding on tree leaves.
3. Larger animals such as Elephants, Deer, giraffe etc. grazing on shoots and/or fruits of trees.

b.Secondary Consumers: These are carnivores and feed on primary consumers.

Eg: Birds, Lizards, Frogs, Snakes and Foxes.

c.Tertiary Consumers:

1. These are secondary carnivores and feed on secondary consumers

2. These include top carnivores like Lion, Tiger.

3.Decomposers:

1. These include wide variety of saprotrophic micro- organism like;

2. Bacteria (Bacillus Sp., Clostridium sp., pseudomonas.
3. Fungi (Aspergillus sp., Ganoderma sp., Fusarium.
4. Actinomycetes (Streptomyces).
5. They attract the dead or decayed bodies of organisms & thus decomposition takes place.
6. Therefore, nutrients are released for reuse.

II. Abiotic components: The way in which plants and animals grow and carry out their different activities is a
result of several abiotic factors. These factors are light, temperature, water, atmospheric gases, wind as well
as soil (edaphic) and physiographic (nature of land surface) factors.

Structure and Functions of Desert Ecosystems:

1.Biotic components:

a.Producer Organisms:

1. In a desert, producers are mainly shrubs/bushes; some grasses & a few trees.
2. Dominant plant species include: Succulents (water - retaining plants adapted to arid climate or soil
conditions) & hardy grasses.
3. Besides some lower plants such as lichens & xerophytic mosses are also present.

13
Notes By Prof. SonaliMangam-Panekar Contact No: +91-9960730903
Renaissance Institute of Management Studies, Chandrapur
b.Consumer Organisms:

1. These include animals such as insects, reptiles which are capable of living in xeric conditions
8
2. Besides some nocturnal rodents, birds & some mammalians like camel etc. are also found.

c.Decomposers:

1. Due to poor vegetation with very low amount of dead organic matter, decomposers are poor in desert
ecosystem.
2. The common decomposers are some bacteria & fungi, most of which are hemophilic.
3. Abiotic components: Due to high temperature & very low rainfall, the organic substances are poorly
present in the soil

Structure and functions of Grassland Ecosystems:

I. Biotic components:

a. Producer Organisms:

1. In grassland, producers are mainly grasses; though, a few herbs & shrubs also contribute to primary
production of biomass.
2. Some of the most common species of grasses are:
3. Brach aria sp., Cynodon sp., Desmodium sp., Digit aria sp.

b.Consumers: In grassland, consumers are of three main types.

Primary Consumers:

1. The primary consumers are herbivores feeding directly on grasses. These are grazing animals such as ;
2. Cows, Buffaloes, Sheep, Goats, Deer, Rabbits etc.
3. Besides them, numerous species of insects, termites, etc are also present.

Secondary Consumers:

1. These are carnivores that feed on primary consumers (Herbivores)

2. These include;-Frogs, Snakes, Lizards, Birds, Foxes, Jackals etc.

Tertiary Consumers:

These include hawks etc. which feed on secondary consumers.

Decomposers:

9
1. These include wide variety of saprotrophic micro- organism like: Bacteria; Fungi; Actinomycetes

14
Notes By Prof. SonaliMangam-Panekar Contact No: +91-9960730903
Renaissance Institute of Management Studies, Chandrapur
15
Notes By Prof. SonaliMangam-Panekar Contact No: +91-9960730903
2. They attract the dead or decayed bodies of organisms & thus decomposition takes place.
3. Therefore, nutrients are released for reuse by producers.

II. Abiotic components:

1. These include basic inorganic & organic compounds present in the soil & aerial environment.
2. The essential elements like C, H, N, O, P, S etc. are supplied by water, nitrogen, nitrates, Sulphates,
phosphates present in soil & atmosphere.

Structure and functions of Grassland Ecosystems:

1. Biotic components:

Producer Organisms: It includes submerged, free floating and amphibious macrophytes (like; Hydrilla,
Utricularia, Wolfia, Azolla, Typha etc.) and minute floating and suspended lower phytoplanktons (like; Ulothrix,
Spirogyra, Oedogonium etc.)

2. Consumer Organisms:

1. Primary consumers: These are zooplanktons (ciliates, flagellates, other protozoan, small crustaceans) and
benthos.
2. Secondary consumers: These are carnivores like insects and fishes feeding on herbivores
3. Tertiary consumers: These are the large fishes feeding on small fishes.

3. Abiotic component: These are the inorganic as well as organic substances present in the bottom soil or
dissolved in water. In addition, to the minerals, some dead organic matter is also present.

Industrial Ecology

Industrial ecology is the study of systemic relationships between society, the economy, and the natural
environment. It focuses on the use of technology to reduce environmental impacts and reconcile human
development with environmental stewardship while recognising the importance of socioeconomic factors in
achieving these goals.

Industrial ecology studies often quantify the use and cycling of materials and energy in society and their
exchanges (extraction and emissions) with nature. Such analyses focus on different levels and scales, from
eco-industrial parks and cities to nations and the global economy.

The term ‘industrial ecology’ derives from a recognition that economic systems (such as manufacturing
processes) and ecosystems are similar. Industrial ecology draws on various concepts from ecology, including
material and energy cycles, complex adaptive systems, and ecological networks. Erkman (1997) highlighted
the similarities between industrial and natural ecology in their definition of the field:

Methods and approaches used in industrial ecology include:

Renaissance Institute of Management Studies, Chandrapur

  Material flow analysis - the quantification of mass and energy flows in systems ranging from industrial
plants to the global economy, including in temporally dynamic states
 Life cycle assessment - the systemic analysis of environmental flows and related impacts that arise
throughout the life cycles of products and services, from raw material extraction to end-of-life disposal
 Environmentally extended input-output analysis - a method to quantify environmental footprints
based on the exchanges between economic sectors, and with the environment
 Industrial symbiosis - the study of the exchange of waste as a resource among nearby industrial
facilities, akin to synergistic physical relationships among biological species

Other approaches, such as socioeconomic metabolism for national economies, urban metabolism for cities,
and the analysis of important socioeconomic factors such as consumer behaviour, business models, and public
policy
Industrial ecology has contributed to various ideas about economic systems that aim to improve resource
efficiency, i.e. minimizing waste and maximising the services delivered by using resources. These ideas have
culminated in the concept of the circular economy, which became widespread in the 2010s. Today, industrial
ecology provides scientifically rigorous methodologies, tools, and approaches for understanding and applying
circular economy practices

Recycling Industry

Recycling is the process of converting waste materials into new materials and objects. The recovery of energy
from waste materials is often included in this concept. The recyclability of a material depends on its ability to
reacquire the properties it had in its original state. [1] It is an alternative to "conventional" waste disposal that
can save material and help lower greenhouse gas emissions. It can also prevent the waste of potentially useful
materials and reduce the consumption of fresh raw materials, reducing energy use, air pollution
(from incineration) and water pollution (from landfilling).
Recycling is a key component of modern waste reduction and is the third component of the "Reduce, Reuse,
and Recycle" waste hierarchy.[2][3] It promotes environmental sustainability by removing raw material input
and redirecting waste output in the economic system. [4] There are some ISO standards related to recycling,
such as ISO 15270:2008 for plastics waste and ISO 14001:2015 for environmental management control of
recycling practice.
Recyclable materials include many kinds of glass, paper, cardboard, metal, plastic, tires, textiles, batteries,
and electronics. The composting and other reuse of biodegradable waste—such as food and garden waste—is
also a form of recycling.[5] Materials for recycling are either delivered to a household recycling center or picked
up from curbside bins, then sorted, cleaned, and reprocessed into new materials for manufacturing new
products.
In ideal implementations, recycling a material produces a fresh supply of the same material—for example,
used office paper would be converted into new office paper, and used polystyrene foam into new polystyrene.
Some types of materials, such as metal cans, can be remanufactured repeatedly without losing their
purity.[6] With other materials, this is often difficult or too expensive (compared with producing the same
product from raw materials or other sources), so "recycling" of many products and materials involves
their reuse in producing different materials (for example, paperboard). Another form of recycling is
the salvage of constituent materials from complex products, due to either their intrinsic value (such as lead
from car batteries and gold from printed circuit boards), or their hazardous nature (e.g. removal and reuse
of mercury from thermometers and thermostats)
_________________________________
17
Notes By Prof. SonaliMangam-Panekar Contact No: +91-9960730903
Renaissance Institute of Management Studies, Chandrapur
Introduction to Ecological Pyramid
An ecological pyramid is a graphical representation of the distribution of biomass or energy within an
ecosystem. The biomass is distributed according to the number of individual organisms in each trophic level.
Each step or level of the food chain forms a trophic level. The autotrophs or the producers are at the first
trophic level. They fix up the solar energy and make it available for heterotrophs or the consumers. The
herbivores or the primary consumers come at the second, small carnivores or the secondary consumers at the
third, and larger carnivores or the tertiary consumers form the fourth trophic level. The different types of
ecological pyramids are based on how much energy or biomass is available to each trophic level.

Ecological Pyramid :
The graphical representation of the relationship between various living beings at various trophic levels within
a food chain is called an ecological pyramid. The pyramid is formed on the basis of the number of organisms,
energy and biomass, and just like the name suggests, these are shaped in the form of a pyramid.
The theory of ecological pyramid was suggested by Raymond Linderman and G.Evylen Hutchinson. The
ecological pyramid is also often known as the energy pyramid .
------------------------------------------- ----------------------------------------------------------------------------------------------------
18
Notes By Prof. SonaliMangam-Panekar Contact No: +91-9960730903
Renaissance Institute of Management Studies, Chandrapur
The bottom of the pyramid, which is also the broadest part is occupied by the ones at the first trophic level,
that is the producers. The next level of the pyramid is occupied by primary consumers. This is followed by the
next level in the pyramid, belonging to the secondary and tertiary consumers.

19
Notes By Prof. SonaliMangam-Panekar Contact No: +91-9960730903
Renaissance Institute of Management Studies, Chandrapur
Types of Ecological Pyramid
Ecological pyramids can be of three kinds. These are as follows:
 Pyramid of numbers
 Pyramid of biomass
 Pyramid of energy

Pyramid of Numbers

This ecological pyramid takes into account the number of organisms present at each trophic level, making up
that level for the pyramid. The number of organisms decreases while going higher up the pyramid. The ones at
the bottom are the producers who are present in the largest number and hence form the base of the
ecological pyramid.
Pyramid of Biomass

This ecological pyramid takes into consideration the amount of biomass that is produced at each trophic
level as it adds to the pyramid. This pyramid is usually upright except for exceptional cases like the marine
ecosystem where the number of phytoplanktons is lesser than the number of zooplanktons that depend on
them.
The producers or the autotrophs have the highest level of biomass in this pyramid. The next level of primary
consumers have lesser biomass than the producers and similarly, the secondary consumers have lesser
biomass than the primary consumers. As a result, the level of the pyramid that has the least biomass is at the
top of the pyramid.

Pyramid of Energy

This pyramid shows the flow of energy that is in the direction of the consumers and comes from the
producers. This pyramid is always in an upright form since it signifies the flow of energy within a food chain,
something that is always unidirectional. The typical energy pyramid has three levels: the producer level, the
consumer level, and the decomposer level. The flow of energy in an ecological pyramid is from bottom to top,
which means energy from the autotrophs, who are also the primary producers, goes to the primary
consumers, meaning those who consume these plants.

20
Notes By Prof. SonaliMangam-Panekar Contact No: +91-9960730903
Renaissance Institute of Management Studies, Chandrapur
At the next step, the energy goes to the secondary consumers who eat the primary consumers. The producer
level is the bottom of the pyramid and contains the green plants that use photosynthesis to create their own
food. The consumer level is made up of animals that eat the plants at the producer level. The decomposer
level is the top of the pyramid and contains organisms that are responsible for breaking down dead matter.
The energy pyramid represents the energy flowing through each trophic level while also showing the amount
of energy at each level and the energy that is lost during the transfer to another trophic level. In simpler
terms, this pyramid helps to quantify the energy transfer within the food chain as it goes from one organism
to another. The energy pyramid is always upright because the energy level only decreases as it moves in the
upward direction, from one level to the next one.
Each trophic level contains about ten times less energy than the previous level because some of the energy is
lost as heat.

Importance of the Ecological Pyramid

The ecological pyramid is highly significant in an ecosystem and the reasons are explained below-
 An ecological pyramid shows how efficiently energy is transferred from one level to the other and also
helps to quantify energy in a food chain.
 This pyramid also shows how various organisms in various ecosystems feed on each other, highlights
their food patterns and explains the relationship between the various levels within it.
 The ecological pyramid also helps in monitoring the overall health and condition of an ecosystem, and
helps in restoring balance. It also helps to understand how any further damage to an ecosystem can be
prevented.

Limitations of the Ecological Pyramid

The ecological pyramid comes with its own set of limitations since it overlooks a couple of important aspects.
These have been discussed below:
 The ecological pyramid does not take saprophytes into consideration and assumes them as
unimportant in the ecosystem, even though they play a highly important role in maintaining the
balance of the environment.
 There is no mention of diurnal or seasonal variations in this pyramid, the concept of climate or
seasons is completely unassumed here.

21
Notes By Prof. SonaliMangam-Panekar Contact No: +91-9960730903
Renaissance Institute of Management Studies, Chandrapur
  The ecological pyramid is only applicable in case of simple food chains, something that in itself
is a rarity.
 Neither does the ecological pyramid explain the concept of a food web.
 This pyramid does not mention anything about the rate of energy transfer that occurs from one
trophic level to the other trophic level.

--------------------------------------------------------------------------------------------------------------------------------------------------
22
Notes By Prof. SonaliMangam-Panekar Contact No: +91-9960730903
Renaissance Institute of Management Studies, Chandrapur