ENERGY FLOW IN AN ECOSYSTEM
-
In an ecosystem, there is transfer or flow of energy from one trophic level to the other in succession.
-
A trophic level can be defined as the number of links by which it is separated from the producer.
-
The pattern of eating and being eaten up forms a liner chain which is called as a Food Chain. It can always be traced back to the producers i.e. Green plants.
-
The producers trap radiant energy from the sun and convert it into chemical or potential energy of organic compounds such as carbohydrates, fats and proteins.
-
When a herbivore eats a plant (or when bacteria decompose it), the organic compounds are oxidized to release energy.
-
The energy released is equivalent to the amount of energy used in synthesizing the substances. This is the first law of thermodynamics.
-
However, some of the energy is not useful and lost as heat. This is the second law of thermodynamics.
-
If this animal, is eaten by another one, along with transfer of energy from herbivore to carnivore a further decrease in useful energy occurs as the carnivore oxidizes the organic substances in the herbivore to synthesize its own cell constituents.
-
Such transfer of energy from one organism to another sustains the ecosystem.
-
The number of steps in a food chain are limited to four or five, since the energy available at each step decreases.
