Gross primary productivity

Definition

Gross primary productivity (GPP) is the total amount of energy captured by autotrophs through photosynthesis in an ecosystem. It represents the rate at which producers convert solar energy into chemical energy as biomass.

5 Must Know Facts For Your Next Test

1. GPP is measured in units of energy per unit area per unit time, such as Joules per square meter per year (J/m²/year).
2. It includes all the energy produced by autotrophs before any is used for respiration.
3. GPP forms the foundation of the energy pyramid and influences the net primary productivity (NPP) available to consumers.
4. Factors affecting GPP include light availability, temperature, water supply, and nutrient levels.
5. In ecosystems with abundant resources, such as tropical rainforests, GPP can be significantly higher compared to resource-limited ecosystems like deserts.

Review Questions

Related terms

Net Primary Productivity (NPP): The rate at which producers store energy as biomass after accounting for respiration losses.

Autotrophs: Organisms that produce their own food from inorganic substances using light or chemical energy.

Respiration:

The metabolic process where organisms convert biochemical energy from nutrients into ATP, releasing waste products.