Question

Secondary productivity is defined as

• A. the rate of production of organic matter during photosynthesis.
• B. the available biomass for the consumption to heterotrophs.
• C. the rate of formation of new organic matter by consumers.
• D. gross primary productivity minus respiration losses.

Answer 1

Answer: (C)

Gross primary productivity of an ecosystem is the rate of production of organic matter during photosynthesis. A considerable amount of GPP is utilised by plants in respiration.
Gross primary productivity minus respiration losses (R), is the net primary productivity (NPP).
GPP - R = NPP
Net primary productivity is the available biomass for the consumption to heterotrophs (herbiviores and decomposers).
Secondary productivity is defined as the rate of formation of new organic matter by consumers.