Carrying capacity

Science

Definition

Carrying capacity (K) is the maximum population size of a species that an environment can sustain indefinitely given the available resources such as food, water, habitat, and other necessities. When a population exceeds its carrying capacity, limiting factors cause the growth rate to decline.

Examples

  • An island can support only a certain number of deer before overgrazing depletes the vegetation
  • The carrying capacity for fish in a lake depends on oxygen levels, food supply, and predation
  • Human carrying capacity on Earth is debated and depends on technology, consumption patterns, and resource distribution
Key Fact

Logistic growth model: dN/dt = rN(1 − N/K), where K is carrying capacity and population growth slows as N approaches K.

Related Terms

Population growth Population ecology Population dynamics Community ecology

Study This Concept

Practice carrying capacity with free review games in these units:

AP Environmental Science Unit 3: Populations