Question

In the following food chain 5 J of energy is available to man. How much energy is available at producer level ?
Plants → Sheep → Man
Which law governs the flow of energy in food chains.

Answer 1

Dear student.

According to 10% law, only 10% of energy is transfer from one trophic level of the food chain to the next, rest 90% of it is lost as heat into the environment and some of it is used in digestion or respiration and for doing other work like growth, repair etc. Plants absorb 1% sun energy for primary production and can store only 10% of the utilized energy as net production available for the herbivores. When the plants are consumed by animal, about 10% of the energy in the food is fixed into animal flesh which is available for next trophic level (carnivores). When a carnivore consumes that animal, only about 10% of energy is fixed in its flesh for the higher level.

Energy available to man= 5J

Energy available to sheep = 50J = 5 * 10J.

Energy available to Plants = 500J= 50 * 10J

So, the energy available to producer will be 500J.

Regards.