Utilisateur:Pixeltoo/Capacité de charge

The supportable population of an organism, given the food, habitat, water and other necessities available within an environment is known as the environment's carrying capacity for that organism. For the human population, more complex variables such as sanitation and medical care are sometimes considered as part of the necessary infrastructure.

As population density increases, birth rate often increases and death rates typically decreases. The difference between the birth rate and the death rate is the "natural increase." The carrying capacity could support a positive natural increase, or could require a negative natural increase. Carrying capacity is thus the number of individuals an environment can support without significant negative impacts to the given organism and its environment. A factor that keeps population size at equilibrium is known as a regulating factor. The origins of the term lie in its use in the shipping industry to describe freight capacity, and a recent review finds the first use of the term in an 1845 report by the US Secretary of State to the Senate (Sayre, 2007).

Below carrying capacity, populations typically increase, while above, they typically decrease. 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 may vary for different species and may change over time due to a variety of factors, including: food availability, water supply, environmental conditions and living space.

La capacité de charge, d'un environnement donné, est la population supportable d'un organisme, étant donné La population supportable d'un organisme, étant donné la nourriture, l'eau et d'autres besoins disponibles au sein d'un environnement est appelé la capacité de charge pour cet organisme. Pour la population humaine, des variables plus complexes tel que