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Function of an ecosystem:



Each ecosystem performs some functions in a systematic manner. The major seven functional aspects of the ecosystem are as follows:

          Energy flow

          Food chain and food web relationships

          Material cycling

          Biological diversity and its stability

          Primary and secondary productivity

          Ecosystem regulation and Homeostasis

          Development and evolution of ecosystems


Primary Productivity: Primary productivity of an ecosystem is the rate at which radiant energy is converted into organic matter either by photosynthesis or chemosynthesis by the primary producers. It involves loss of energy in terms of respiratory losses which is required for the maintenance of the producers. The producers are left with little less organic matter than what was actually produced by them which is referred to as Net Primary Productivity (NPP). When respiratory losses (RL) are added to this value it gives the Gross primary productivity (GPP).

                                                GPP = NPP + RL


Secondary Productivity: Secondary productivity of an ecosystem is the rate at which chemical energy is converted by the consumers for their metabolic activities.


Homeostasis: It is the ability of biological system to resist change and to remain in the state of equilibrium. The homeostasis mechanism is the inbuilt resistance as the ecosystems are capable of self maintenance and self regulation. Example - Regulatory mechanism keeps the body temperature of human beings fairly constant despite various environmental stresses.



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