NEET BIOLOGY

Detailed explanation-1: -desertification, also called desertization, the process by which natural or human causes reduce the biological productivity of drylands (arid and semiarid lands).

Detailed explanation-2: -But since the late 1960s, the Sahel has endured an extensive and severe drought. Desertification occurs when land surfaces are transformed by human activities, including overgrazing, deforestation, surface land mining, and poor irrigation techniques, during a natural time of drought.

Detailed explanation-3: -Desertification is the process by which vegetation in drylands i.e. arid and semi-arid lands, such as grasslands or shrublands, decreases and eventually disappears.

Detailed explanation-4: -Originally it was believed that the drought in the Sahel primarily was caused by humans over-using natural resources in the region through overgrazing, deforestation and poor land management. In the late 1990s, climate model studies suggested that large scale climate changes were also triggers for the drought.

Detailed explanation-5: -This overgrazing causes a loss of vegetation-when herds of animals eat all the grass on a piece of land, the soil underneath is left vulnerable and unable to grow back quickly enough to meet the grazing demand of the livestock.