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Human-caused disasters

Although climatic variability is a natural phenomenon, the increasing frequency and severity of extreme events can be in part attributed to human activities such as deforestation and inappropriate management of land and water resources. For example, clearing of tropical forests in Central and Western Africa has altered the local climate and rainfall patterns, and increased the risk of drought. Clearing of vegetation may also increase run-off and soil erosion. Damming of rivers and draining of wetlands reduces the environment's natural ability to absorb excess water, enhancing the impacts of floods. For example, countries in Southern Africa experienced devastating floods in 1999 and 2000 which affected more than 150 000 families (Mpofu 2000). Degradation of wetlands such as the Kafue wetlands in Zambia, damming of rivers, deforestation and overgrazing lowered the environment's ability to absorb excess water and magnified the impact of the floods (Chenje 2000, UNDHA 1994).

Environmental impacts of refugees in Africa

Environmental rehabilitation of refugee camps in Africa alone could cost as much as US$150 million a year. Visible evidence of environmental degradation is most obvious in long-standing asylum countries such as Kenya and Sudan. Land surrounding the refugee camps has been stripped clean of trees and vegetation. In such situations, refugees may have to walk up to 12 km in search of water and firewood.

In the early 1990s, an estimated 20 000 ha of woodlands were cut each year in Malawi to provide firewood and timber for the various camps hosting Mozambican refugees, while in 1994, at the height of the refugee crisis near the Virunga National Park in the Democratic Republic of Congo (formerly Zaire), refugees were removing some 800 tonnes of timber and grass each day from the park - an amount far in excess of a possible sustainable yield. Despite efforts to restrict the impact on the park, almost 113 km2 have been affected, of which more than 71 km2 have been completely deforested. At another site in South Kivu, almost 38 km2 of forest were lost within three weeks of the arrival of refugees. In December 1996, more than 600 000 refugees from Burundi and Rwanda were housed in the Kagera region in northwest Tanzania. More than 1 200 tonnes of firewood were consumed each day - a total of 570 km2 of forest were affected, of which 167 km2 were severely deforested.

Source: UNHCR 2001a

Over the past three decades, millions of Africans have sought refuge from natural and human-made disasters with both environmental and socio-economic impacts. At the end of 2000, there were 3.6 million refugees in Africa, 56 per cent of whom were under 18 years of age (UNHCR 2001b). Often refugees are settled in fragile ecosystems where they exert considerable pressure on the natural resources, as they have no other means of survival (see box). Refugee populations also sometimes experience further conflicts with neighbouring communities, through competition for resources.