What Is a Productivity Model?

Primary productivity refers to the total amount of organic matter produced by plant communities in the ecosystem per unit time and unit area. It is generally expressed as the content (mass number) of organic carbon per day and per square meter. Primary productivity can be divided into total primary productivity and net primary productivity. Total primary productivity refers to the amount of organic carbon (also called total primary productivity) fixed by green plants through photosynthesis per unit time. GPP determines the initial material and energy that enters the terrestrial ecosystem. Net primary productivity refers to the part of the organic carbon fixed by vegetation minus its own respiratory consumption, which is used for vegetation growth and reproduction (also known as net primary productivity). The relationship between the two is: net primary productivity = total primary productivity-an assimilated product consumed by the autotrophic organism's own breathing. ^[1]

Primary productivity

Net primary productivity refers to the ability of green plants to photosynthesize using sunlight, that is, sunlight + inorganic matter + H2O + CO2 heat + O2 + organic matter to fix and convert inorganic carbon (CO2) into organic carbon. Multiple satellites

Gross Primary Productivity (GPP) refers to the amount of organic carbon fixed by organisms (mainly green plants) through photosynthesis in a unit of time. It is also called total primary productivity. GPP determines the initial entry into terrestrial ecosystems. Matter and energy.

Net Primary Productivity (NPP) refers to the part of the organic carbon fixed by vegetation minus its own respiratory consumption. This part is used for the growth and reproduction of vegetation. It is also called net primary productivity.

Relationship between the two: NPP = GPP-Ra

Ra: Assimilation product consumed by the autotrophic organism's own respiration. ^[2]