Branch : Automobile Engineering�Semester : 3rd ,Winter-2021

Subject : Environmental Studies

Chapter : 03

Topic : Eco-System

Faculty : Er. Sourin Mohanty

Mayurbhanj School Of Engineering, Baripada

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ECOSYSTEMS

Ecosystem

An ecosystem is a natural unit consisting of all plants, animals, and micro-organisms in an area functioning together with all the non-living physical factors of the environment.

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According to British ecologist Arthur Tansley (1935), an ecosystem is a system that arises from the integration of all living and non-living factors of the environment.

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• An ecosystem is a self-sustained community of plants and animals existing in its own environment.

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• The term ecosystem may be defined as a system resulting from the integration of all the living and non living factors of the environment. Desert, Forest, Ocean, Grasslands, Mountains, etc. are all ecosystems.

What is an ecosystem?

Ecosystem is a system of living things that interact with each other and with the physical world.

Classification of ecosystem

Kinds of Ecosystems

Natural Ecosystems

Man-made Ecosystems

Terrestrial Ecosystems

Aquatic Ecosystems

Fresh water Ecosystems

Marine Ecosystems

Lentic Ecosystems (Static water)

Lotic Ecosystems (Running water)

Structure of an Ecosystem

Living (Biotic) Components

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• Producers
• Consumers
• Decomposers

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Non-living (Abiotic) Components

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• Physical factors
• Chemical factors
• Limiting factors

Biotic Components of Ecosystems

Producers (or autotrophs)

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Green plants and some bacteria which manufacture their own food.

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Consumers (or heterotrophs)

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Animals which obtain their food from producers

• Primary consumers
• Secondary consumers
• Tertiary consumers

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Decomposers

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Bacteria and fungi that decompose dead organic matter and convert it into simpler parts

Abiotic Components of an Ecosystem

Physical Factors

Rainfall Sunlight Humidity Temperature Nature of soil Water currents

Chemical Factors

Salinity of Water Nutrients present in soil Oxygen dissolved in water

Percentage of water and air in soil

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Food, water, shelter and space are

Limiting Factors

limiting factors for the growth of population of human and

animals.

Functions of an Ecosystem

• Food chain and food web

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• Energy flow

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• Ecological pyramids

Food Chain

The transfer of food energy from the source (plants) through a series of organisms by repeated eating and being eaten up is referred to as food chain.

Food Web

The interlocking pattern formed by several food chains that are linked together is called a food web.

Food Chain

• A series of organism by repeated eating and being eaten up is referred as food chain.

Types:

• Grazing food chain-a common chain
• Detritus food chain- chain derived by the organic wastes and dead matter from grazing food chains

The process of eating and being eaten

Grazing and Detritus Food Chain

Detritus (Dead organic matter) Food Chain

Grazing Food Chain

You will see the terms food chains and food webs. They describe the same series of events that happen when one organism

consumes another to survive.

THE PRODUCERS

Producers are the beginning of a simple food chain. Producers are plants and

vegetables.

THE PRODUCERS

^ All energy comes from the Sun and plants are the ones who make food with that energy. They use the process of photosynthesis.

^ Plants

nutrients

also make

for other

organisms to eat.

Consumers are the next link in a food chain. There are three levels of consumers.

FEEDING RELATIONSHIPS

A food chain shows a simple feeding relationship.

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Sun → grass → rabbit → fox

Note: All food chains start with the sun

All food chains start with ENERGY from the sun

Thank You