The capacity of population to grow is greater than the power of the earth to provide resources. Given the procreative capacity of humanity and the inherently finite availability of the earth's resources, in this way of thinking, human population is the single greatest influence on the status of the earth and its resources.
Malthus stressed that population growth is effectively "geometric," since the multiple offspring of a single mating pair of animals or people are each capable of producing multiple offsprings themselves.
(I): Impact , (P): Population , (A): Affluence , and (T): Technology.
Present day adherents to a position established by Malthus in the nineteenth century that population growth outstrips limited natural resources and presents the single greatest driver of environmental degradation and crisis.
Others have argued that development radically lowers human impact, at a rate far greater than the growth of population. It is predicted that as development initially occurs, environmental impact increases, with per capita use of resources rising, pollution increasing, and damage to ecosystems like forests rising, and doing at a rising rate. However after a threshold, regulation, affluence, and economic transition begin to increase and impacts of humans fall dramatically.
upside down U on graph.
Forest Transition Theory
A model that predicts a period of deforestation in a region during development, when the forest is a resource or land is cleared for agriculture, followed by a return of forest when the economy changes and population out migrates and/or becomes conservation-oriented.