Read at : Google Alert – desertification
A slightly different problem occurs with land ecosystems. These tend to be within one country, but the international community is still concerned with trying to protect them, particularly because some of the world’s poorest people live in areas threatened by rapid loss of productive capability through desertification, that is, the transformation of land areas into essentially uninhabitable deserts that cannot support human populations. This raises its own problems regarding a coordinated international strategy.
Dry land ecosystems such as grasslands and savannahs cover over one-third of the world’s land area and are home to many of the world’s poorest people, whose livelihoods depend critically on the land. Yet precisely because these ecosystems are not naturally lush, dry land areas are fragile and highly vulnerable to land degradation.
Desertification is caused by a combination of climactic variations and human activities. Untouched dry lands suffer during periods of drought, but are generally able to recover on their own. However, when these areas are simultaneously exploited for human economic gain, the combined stress on the ecosystem can be too much. Thus, over-cultivation, over-grazing, deforestation, and poor irrigation by humans play a large role in the desertification problem.
The results of desertification can be disastrous. The key effect is the loss of the primary resources—fertile topsoil, vegetation, and crops—that sustain economic activity. In impoverished regions, such as sub Saharan Africa, the ramifications are serious. If desertification progresses enough, the already marginalized people who depend on this land will find that the land can no longer provide enough food and water for survival. The result is famine that starves many people and animals, forces large displacements of populations, and entails massive economic disruption.