Question

What is Gross primary productivity (GPP)?

• A. It refers to the environmental factors.
• B. Number of plants in an ecosystem.
• C. It is the rate of production of organic matter during photosynthesis.
• D. Solar energy exposed to plants in an ecosystem.

Answer 1

Answer: (C)

Primary productivity is of two types:
A. Gross primary productivity (GPP): It is the rate of production of organic matter during photosynthesis.
B. Net primary productivity (NPP): It is the biomass available for the consumption of heterotrophs (herbivores and decomposers).
A part of GPP is utilized by plants in respiration (R), whereas the remaining is available for the next trophic level. Hence, NPP = GPP - R