The carrying capacity of an ecosystem can be defined as the maximum number of organisms (or a particular species) that can be indefinitely supported. The carrying capacity includes parameters such as food, space, predation, competition, etc. Human beings can control the carrying capacity of an environment by intervening in any of these parameters. A control on the amount of food available can be achieved by introducing organisms that eat the same food. For examples, deer population can be controlled by introducing cows in the area, as they eat same food (grass) and given that total food is fixed, deer will now have less food availability. Another measure can be introduction of predators. Wolves or tigers can eat deer and control their population. 

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