Carrying capacity

In ecology, the carrying capacity of an environment is the number of organisms of a particular species that can live there depending on the amount of resources it has. If too many organisms live in an environment, it is called overpopulation.
The carrying capacity of an environment can change, and humans can have an effect on the carrying capacity. For example, agriculture and irrigation allow feeding more people; meaning the human carrying capacity is increased.
Some things that can change an environment's carrying capacity are pollution and the use of natural resources.