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Question
What is ten per cent law? Explain with an example.
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Solution
According to the 10 per cent law, only 10 per cent of the energy entering a particular trophic level of organisms is available for transfer to the next higher trophic level.
In the following food chain, only 10 per cent of energy is transferred to the next trophic level. The flow of energy is shown below.
Plants → Grasshopper → Frog → Snake → Hawk
100,000J 10,000J 1,000J 100J 10J
When the energy available at the producer level is 100,000 J, only 10 J of energy is available to the hawk.
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