In an ecosystem if the Net Primary Productivity (NPP) of first trophic level is 100x ( kcal m-2 ) yr-1, what would be the GPP (Gross Primary Productivity) of the third trophic level of the same ecosystem?
- x10 ( kcal m-2 ) yr-1
- x ( kcal m-2 ) yr-1
- 10x ( kcal m-2 ) yr-1
- 100x3x ( kcal m-2 ) yr-1
Answer
(3) 10x ( kcal m-2 ) yr-1
Solution
NPP of the first trophic level (producers) = 100x ( kcal m-2 ) yr-1
As per NCERT (10% law of Lindeman), only about 10% of the energy of one trophic level is transferred to the next level as its gross productivity.
Gross productivity transferred = 10100 100x = 10x ( kcal m-2 ) yr-1
Answer: (3)