Question

Amount of organic matter stored by producers for heterotrophs per unit area in per unit time is known as productivity.

• A. net primary
• B. gross primary
• C. secondary

Answer 1

The correct option is A net primary

Gross primary productivity is the amount of organic matter synthesized by producers per unit area in unit time. It is equivalent to the total photosynthesis. It also indicates the capacity of producers to assimilate solar energy into living matter.
Net primary productivity is the amount of organic matter stored by producers (for heterotrophs) per unit area in per unit time. When respiration losses are deducted from the gross primary productivity, it results in net primary productivity. It is the productivity that accumulates as biomass.