The carrying capacity of earth of the environment is the population that the ecosystem can sustain for a long time. It refers to ability of the resources available to support and provide for the need of human being. It is a balance between the renewable resources and the population for a sustain the population for a considerable long period. For example, the mice can sustain if plenty of grass available. If the population of mice increases then a threat to the consumption of grains. Similarly, the death of rats has a direct effect on the survival of other species, like snakes or owls wheed feed on them. However, with sauce of time the rats regenerate other species also increase in number. Similarly, when grass is destroy rabbits which feed. On them gradually stat dying. The lions and other sped which predate on rabbit also start dying due to starvation.
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Earth has a carrying capacity and the human population has grown too far the carrying capacity, of the earth, in 1980, it was estimated that population of developed countries rise by 12% whereas underdeveloped countries with 50%. The population of world crossed 6 billion. So there acute deficit in land, water and energy. There is no balance of food supply and demand.
Such decrease in the world food yield caused environmental stress and there is the question of deforestation, short of water supply. Rapid population growth resulted in environmental damage, which includes global climate change. The conjuring capacity of earth tails. So special attention to be paid to critical resources like food, water and environment factors.