Definition - What does Primary Productivity mean?
Primary productivity refers to the degree to which autotrophic organisms (primarily plants and algae) convert energy into organic substances through photosynthesis or chemosynthesis. Since the process of photosynthesis consumes carbon dioxide and produces oxygen, it is of great importance to the environment. Primary productivity refers to the amount of carbon-fixing biomass produced.
Safeopedia explains Primary Productivity
The productivity of autotrophs that create their biomass without consuming other organisms forms the basis of the food chain and modifies the atmosphere making life on earth possible for heterotrophs that either feed directly off autotrophs or consume the organisms that do so. For example, a human eats vegetables (produced by autotrophs) and meat (produced by grazing animals). The process of photosynthesis on land and in the sea produces oxygen, something heterotrophs are unable to do, and reduces the greenhouse gas carbon dioxide in the process. Primary production is, therefore, essential to all life. Chemosynthesis is performed by certain bacteria and is of lesser importance.