The energy of the sun is transferred from one trophic level to another i.e. from plants to herbivores to small carnivores and then to large carnivores. Plants are able to trap only 1% of the energy of the sun and later on, only 10% of this are available for the organism of the next trophic level.
Energy flow in trophic level
In a food chain, the energy flow follows the 10 per cent law. According to this law, only 10 per cent of energy is transferred from one trophic level to the other; the rest is lost into the atmosphere.
- The green plants in a terrestrial ecosystem capture about 1% of the energy of sunlight that falls on their leaves and converts it into food energy.
- When green plants are eaten by primary consumers, a great deal of energy is lost as heat to the environment, some amount goes into digestion and in doing work and the rest goes towards growth and reproduction. An average of 10% of the food eaten is turned into its own body and made available for the next level of consumers.
Therefore, 10% can be taken as the average value for the amount of organic matter that is present at each step and reaches the next level of consumers.