The annual net primary productivity of the whole biosphere is approximately.

Q. Gross primary productivity of an ecosystem is 170 tons of organic matted and amount used in respiration is 50 tons. Calculate the net primary productivity of the ecosystem.

Q. Consider the following four statements (A-D) and select the correct option stating which ones are true (T) and which ones are false (F). Statements :

(A) Vertical distribution of different species occupying different levels in a community is called stratification.
(B) Net primary productivity minus respiration losses is the gross primary productivity.
(C) Rate of biomass production is called decomposition
(D) Annual net primary productivity of oceans is 55 billion tons