Answer to Question #115824 in Ecology for Cesca

Question

The net productivity of the different trophic levels in the food chain are as follows:

Grass: 13,883kJ m-2 yr-1
Arctic hare: 2345 m-2 yr-1
Arctic fox: 137 m-2 yr-1

Explain why the net productivity of the Arctic hare is less than the net primary productivity of the grass.

Answer 1

According to the energy pyramid concept, as food energy passes from level to level in a food chain, the amount of energy available to the next higher level decreases.

Grass is the first trophic level or primary producer and Arctic hare is the second trophic level or primary consumer of Arctic food chain. Net productivity of the Arctic hare is less than the net primary productivity of the grass because secondary productivity (net productivity of the Arctic hare) reflects only the utilisation of food (net primary productivity of the grass) for the production of consumer biomass.