What is Gross and net primary production?

Gross primary production (GPP) refers to the total amount of organic matter or biomass produced by photosynthetic organisms in an ecosystem, representing the total energy captured through photosynthesis. Net primary production (NPP) is the amount of organic matter that remains after accounting for the energy used by plants for respiration; it is essentially the energy available for consumption by herbivores and decomposers. In simpler terms, GPP is the total energy produced, while NPP is the energy that contributes to growth and reproduction in the ecosystem.