Q24 of 43 Page 1

What is productivity in an ecosystem? Explain the relationship between gross primary productivity and net primary productivity in an ecosystem.

Productivity in an ecosystem is the rate of biomass production. Gross primary productivity or GPP is the rate of production of organic matter during photosynthesis. Net primary productivity or NPP is the gross primary productivity minus the respiratory loss.


NPP = GPP – R


Where R is the respiratory loss.


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