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Desertification is a gradual process of increased soil aridity.Desertification has been defined in the text of the United Nations Convention to Combat Desertification (UNCCD) as "land degradation in arid, semi-arid and dry sub-humid regions resulting from various factors, including climatic variations and human activities."
Desertification in Africa is exacerbated by human factors such as deforestation, overgrazing, and unsustainable farming methods such as monoculture and excessive use of chemical fertilizers. For example, deforestation reduces the quantity of plants that may anchor soil and protect it from erosion, whereas overgrazing depletes vegetation and ...
Desertification is one of the issues of environmental concern in Nigeria, particularly the northern part of the country. According to UNEP [4] in 1993, Northern Nigeria has one of the highest rates of deforestation in the world at about 3.5%, caused by land degradation, increase in agricultural intensity, over-grazing of livestock, and demand for fuel by cutting down trees.
Ghana's drylands in the northern Sudanese and Guinea savannah regions are especially at risk from erosion; in these areas, land deterioration is known as "desertification." The risk of desertification is present on about 35% of Ghana's land. An estimated $1.4 billion, or 6% of Ghana's GDP, is lost to land degradation each year in the country. [3]
Desertification can be viewed as a process in which the productivity of arid or semi-arid land decreases by 10% or more. [41] Mild desertification signifies a 10 to 25% reduction in productivity, while serious desertification indicates a 25 to 50% decline, and severe desertification denotes a productivity drop exceeding 50%.
The Nama Karoo in South Africa is a xeric shrubland that receives between 100 and 500 millimetres (4 and 20 in) of rain a year. [3]The conversion of productive drylands to desert conditions, known as desertification, can occur from a variety of causes.
The factors responsible for pans include a vegetation-free surface and low humidity, a low water table and poorly consolidated sediment, and a huge amount of fine-grained sandstone and shale. Feedback mechanisms also play a significant role in the process of enlarging the pan; salts are left as water accumulates in depressions, which inhibits ...
Sand dunes in the Sahara Desert. Desert ecology is the study of interactions between both biotic and abiotic components of desert environments. A desert ecosystem is defined by interactions between organisms, the climate in which they live, and any other non-living influences on the habitat.