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Land hunger bites

Area with high risk of water-induced soil degradation: Africa (% of total land area)

Africa is at high risk from waterinduced soil erosion, except for Northern Africa where low rainfall keeps the risk extremely low. The area under risk grows considerably in all scenarios as a result of intensifying agriculture, combined with adverse consequences of climatic change.

Source: IMAGE 2.2 (see technical annex)

Percentage of 2002 cropland severely degraded by 2032: Africa

Bars represent the percentage of 2002 cropland that has become so degraded by 2032 that it is of little value for production.

Source: PoleStar (see technical annex)

Key to charts

Growing populations, economic development and changes in climate all contribute to increasing the risk of land degradation in much of Africa (see chart on the right). Stronger economic growth in the region under Policy First and Sustainability First conditions, implies that the risk of land degradation is higher than in Markets First. The sharper increase apparent in Security First reflects the greater area of land brought into agriculture under this scenario in order to meet the demands of the still rapidly increasing population. It also indicates relative inability to fall back on food imports and diminishing rates of return from improving agricultural practice.

The translation from risk to actual degradation may be mediated in a number of ways, however (see chart on the right). Cropland has been extensively degraded in the past in Africa due to salinization, wind and water erosion. In the worlds of Policy First and Sustainability First, easier access to support services helps farmers to manage soils better, curtailing problems like compaction, erosion and salinization. Policies based on integrated land use management, including more stable land tenure systems, become commonplace in most parts of the region. Technological advances prompted by a combination of government incentives and private sector innovations, help improve productivity of degraded land. The slightly higher level of degradation in Policy First versus Sustainability First reflects slight differences in demand for food - particularly animal products. At the other end of the spectrum, in a Security First scenario, a combination of inequitable land distribution, poor farming methods, unfavourable land tenure systems and inefficient irrigation systems leads to declining productivity of grazing and agricultural lands. Better conditions are, however, maintained in the protected areas serving the elite. The concentration of large numbers of people in fragile areas beyond the control of the land-owning elite further contributes to the degradation of land and severe soil erosion. Similar problems arise in a Markets First situation as better quality agricultural land is taken over for commodity and cash crop production. The environment suffers as a result as soils are 'mined' and the use of fertilizers and pesticides becomes more extensive. Water resources and aquatic ecosystems are particularly damaged.