Carrying capacity
From Free net encyclopedia
As population density increases, birth rates decrease and death rates increase. The carrying capacity is at the point when these two rates are equal. It is usually a range of values, rather than a single point in time.
Carrying capacity is therefore the largest size of a density-dependent population for which the population is at equilibrium (population size neither increases nor decreases). A factor that keeps population size at equilibrium is known as a regulating factor.
Below carrying capacity, populations will tend to increase, while above, they will tend to increase. Population size decreases above carrying capacity due to a range of factors depending on the species concerned, but can include insufficient space, food supply, or sunlight. The carrying capacity of an environment will vary for different species in different habitats, and can change over time due to a variety of factors including trends in food availability, environmental conditions and space.
It is also possible for a species to pass its carrier capacity, in which case the population can drastically fall as shortages in food and water take effect. This is often considered more devastating for a population as it produces stress for the entire species, and populations can fall far below the carrier capacity.he:כושר נשיאה