The amount of biomass or organic matter produced per unit area over a time period by plants during photosynthesis is called

The amount of biomass or organic matter produced per unit area over a time period by plants during photosynthesis is called Gross Primary Production (GPP). GPP represents the total energy assimilated
by plants through photosynthesis before any energy is used by the plants during respiration. It is the total amount of energy captured by plants from sunlight and converted into organic compounds.
(1) Secondary production refers to the amount of biomass or organic matter produced by consumers (heterotrophs) in an ecosystem. It represents the energy stored in the form of new tissues through the consumption of primary producers (plants) or other consumers.
(2) Primary production may refer either to gross primary production or net secondary production. The amount
of biomass produced per unit area over a time period by plants during photosynthesis specifically refers to
Gross Primary Production.
(4) Net primary production (NPP) is the amount of biomass or organic matter that remains after deducting
the energy used by plants during respiration (R) from the gross primary production (GPP). NPP represents the
energy available for the growth and reproduction of plants and the energy transfer to higher trophic levels in the
ecosystem.