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Carrying capacity of ecosystems and human demography

Carrying capacity of ecosystems and human demography

In geography and ecology, anthropization is the conversion of open spaces, landscapes, and natural environments by human action. Anthropogenic erosion is the process of human action degrading terrain and soil. In biology, it also concerns domestication and breeding processes.

Carrying capacity :

refers to the number of individuals who can be supported in a given area within natural resource limits, and without degrading the natural, social, cultural and economic environment for present and future generations. The carrying capacity for any given area is not fixed. It can be altered by technology and resource management practices, but mostly it is changed for the worse by pressures which accompany a population increase [1]. A major symptom of reduction in carrying capacity is the reduction of bioproductivity.
The potential biological productivity per capita is an indication of the potential of a geographic area to support the population of that area. It does not take into account the effects of biomass transfers between different geographic areas or locations. Expressed in tons / capita / growing season. The Ecological Footprint has been used to estimate human demand compared to ecosystem’s carrying capacity.

The carrying capacity of the planet for humans has increased over time, especially with the development of agriculture and other technologies. The industrial revolution has only artificially increased our carrying capacity since it is based on the use of fossil resources, and thus is not indefinitely sustainable.
Our demography relies on economic, political, cultural and religious factors. Three laws in population ecology can be defined : Law of exponential growth, Population self-limitation and Resource-consumer oscillations. Consumption and population shrinking are terms in use when envisioning sustainable development [2].
It seems reasonable to state that active policies on the equation human demography - carrying capacity should concentrate on tight strategies of family planning (Brown L, 2011, World one poor harvest away from chaos) and tight management of natural and other resources.
Furthermore, such major efforts should integrate the global urban land expansion issue. The conversion of Earth’s land surface to urban uses is one of the most irreversible human impacts on the global biosphere. It drives land use and the loss of farmland, affects hydrological systems, biogeochemistry and local climate, fragments habitats, and threatens biodiversity. Studies on the 1970 to 2000 period (based on remotely sensed images to map urban land conversion) state that urban land expansion rates are higher than or equal to urban population growth rates in various regions of the world, suggesting that urban growth is becoming more expansive than compact. These and future expansions are likely to occur into most biologically diverse, sensitive areas, such as forests, savannas and coastline. It is concluded that the explosive growth of cities poses people and the environment at risk [3-7].

Publié ou mis à jour le 14 juin 2012