Discuss the impact of desertification on land, ecosystems and people.
Desertification is ‘the diminution or destruction of the biological potential of the land which can lead ultimately to desert-like conditions’. Mainly as a result of climatic changes, changes in farming and population growth, desertification has had huge impacts on land, ecosystems and people.
Maps of NE of Africa to compare its dry, vegetated and saturated area between May 2007 and May 2011.
It shows a significant decrease in area covered by vegetation and expansion in arid area in Sudan and Ethiopia.
Climatic change (decrease in rainfall and increase in evapotranspiration rate) has led to the death of vegetation; change in farming and overgrazing has made it very difficult for vegetation to re-establish itself while other human activities e.g. overcultivation and deforestation has removed vegetation cover in the area. As a result, here is a reduction in the amount of vegetation in deserted area.

Because of population growth (as a result of high birth rate and/or immigration – refugee), there is a higher demand for woods for cooking, which leads to deforestation and an increase in the area of treeless zones. The decrease in forest cover in Haiti from 1990 through 2005 was about 10% and it is now estimated that the radius of the treeless zone around Khartorm, Sudan is 90km.
The reduction in vegetated and forest area leads to the reduction in biodiversity since it contributes to the destruction of the habitats of animal and vegetable species and micro-organism. Although it is extremely difficult to put an indicator on this loss, reducing the biodiversity, primarily, it affects the food and health of the local people who rely on a large number of different animal and vegetable species, secondly, it is also a loss to the whole of mankind as many genetic strains of cultivated plants which form the basis of the food and health of the world's population originate from the dry zones, their disappearance can affect the possibility of producing plant-based medicines to combat specific diseases or epidemics. The amount of carbon stored in the vegetation in the dry zones, averaging about 30 tonnes per hectare, declines when the vegetation is depleted, which also reduces the amount of carbon exchange by photosynthesis.

Due to the loss of protection by vegetation, landslides occur more frequently in some areas, e.g. Kenya, by the action of water. Moreover, wind and rain remove topsoil surfaces and as a result of reduction in roots of plants that hold soil together. There is a loss of organic matter in the soil, causing soil to be less fertile. In irrigated regions, due to the excessive use of chemical fertilizer, soil might be polluted, increasing coastal erosion and adversely affecting human and animal health. In addition, due to irrigation malpractice, which causes water tables to rise, there might be an increase in salinity and soil acidification. In turn, it reduces the biodiversity of fresh and brackish water and fishing catches. Carbon-rich soils that are frequently found in the dry zones, store a higher quantity of carbon than in the world's vegetation, the destruction of these soils has a very powerful affect on the carbon cycle and boosts the greenhouse effect as a result of the depletion of carbon.
In arid and barren areas, large stretches of deserted land and sandy land provide rich sources for the formation of sand dunes and sandstorms. In areas under the protection of shelterbelts, sparse forests can protect an area 24-38 times that of the height of the trees, which can reduce the wind speed by 34-41%. Not being protected by vegetations, together with human factors (including population growth, the rapid spread of urbanisation and the improper use of land – deforestation, over-grazing, excessive use of water resources), both frequency and intensity of sandstorms in areas such as Xinjian in China. For example, a severe sandstorm in Xinjian Uygur Autonomous Region in 1998 caused an economic loss of over 900 million yuan (equivalent to around £75 m). The increase in frequency and intensity of sandstorms might lead to respiratory diseases as dusty particles are inhaled.
Desertification causes the movement of population away from affected areas to other regions as there is no/extremely little facilities in deserted areas. Because of increased population in the destination area, pressure will be applied to resources such as the soil and fuelwood. It also leads to conflict between different ethnic groups, families and individuals. For example, in 2003, Arab Muslims (nomadic herders) in Egypt moved to Darfur, where Non-Arab Muslims (sedentary farmer) had already settled in. They strived for the land right causing a civil war, which is still ongoing, as a result, 300,000 people have been killed.
Land degradation causes deep gullies to form, in addition to drought, the increase in soil salinity and soil erosion, agricultural productivity declines, leads to food shortages and famine. In Kenya in October 2011, the suffering caused by the worst drought in years compounded with corruption among the authorities caused a serious famine crisis, more than 13 million people were requiring food aid, in which many are malnourished children under the age of 5. The impact on health on people are catastrophic, almost half of the 10 million annual deaths among children under 5 in LEDCs are associated with malnutrition as it weaken the body’s immune system.