The climatic impacts of the destruction of vegetation cover include increased albedo leading to decreased precipitation, which in turn leads exacerbates vegetation loss; increased atmospheric dust loading could lead to decreased monsoon rainfall and greater wind erosion and/or atmospheric pollution.
Land is desertified when it can no longer support the same plant growth it had in the past, and the change is permanent on a human time scale. Many things can cause desertification. Drought, overgrazing, fire, and deforestation can thin out vegetation, leaving exposed soil. If the nutrient-rich top soil blows or washes away, plants may not be able to return. Overfarming or drought can change the soil so that rain no longer penetrates, and the plants lose the water they need to grow. If the changing force is lifted – drought ends or cattle are removed, for example – but the land cannot recover, it is desertified. The loss of productive land for a season or even a few years is one thing, but to lose it effectively for ever is clearly far more serious.
Related category• ECOLOGY AND THE ENVIRONMENT
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