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Structure and components of ecosystem:

The ecosystem comprises of the biotic and abiotic components. These are the basic functional units as they include the organisms and the environment surrounding them which influence the properties of each other and are required for the survival and maintenance also.


Abiotic or the non living environment forms the basic elements of the environment. These basically consist of air, water, soil. The three broad categories are

          Physical environment like climatic factors eg pH, humidity, rainfall.

          Inorganic components like water, oxygen, carbon, nitrogen, sulphur, phosphorus which help in cycling of nutrients in the ecosystem.

          Organic components like lipids, carbohydrates, fats, proteins which form the building blocks for the living body and hence the link between the biotic and the abiotic factors.


Biotic factors include the plants, animals, microorganisms and any other living things. The three broad categories include:

  • Producers :These are the energy transducers which convert solar energy into chemical energy with the help of inorganic and organic substances. The producers  make their own food  and are referred to as autotrophs (auto means self and troph means nourishing). Autotrophs are further of two types photoautotrophs and chemoautotrophs. Photoautotrophs mainly green plants make food through a process called photosynthesis. Chemoautotrophs, utilize energy generated in an oxidation-reduction e.g. microorganisms like sulphur bacteria.

  • Consumers or heterotrophic (hetero-other, trophic-nourishing) organisms are mainly animals. Depending upon the food habits consumers are classified as Herbivores, Carnivores .Herbivores eats plants. Carnivores eat animals. Carnivores are further classified as carnivore of order1 (C1), carnivore of order 2 (C2) and so on depending on their food habits. Omnivores eat both plants and animals.

  • Decomposers are also heterotrophs that depend upon dead organic matter for their food. They are also termed as saprotrophs (sapro means to decompose). They play a very important role in the ecosystem as they recycle nutrients by breaking down complex organic matter found in plant and animal body and ultimately releasing simple substances e.g. microorganisms like bacteria, fungi etc.


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