African Water Development Report 2006 - United Nations Economic ...

PROTECTINGECOSYSTEMSIN AFRICAThe previous chapter mentioned ecosystemhealth and advised that, in order to maintainenvironmental health, sanitation systems shouldnot be allowed to pollute ecosystems and scarceresources should not be depleted. The Rio Declarationof 1992 and the Bonn Recommendationsof 2001 stated in the box below upholdthese views. This is a challenge that many Africannations have to contend with as they faceserious environmental problems, which do notonly affect their socio-economic development,but also cause global concerns. The principalenvironmental problems are deforestation, land(soil) degradation, water resource degradation,unsustainable use of land and water resources,and loss of biological diversity (ECA, 1999).According to the United Nations EnvironmentProgramme (UNEP), the area prone to desertificationworldwide is approximately 38 millionkm² and 6.9 million km², of which 23 per centis in sub-Saharan Africa. Concerns have beenexpressed about Africa’s huge natural resources,including the fact that Africa’s soil resources arevery fragile and sensitive to unwise use, that sub-Saharan Africa’s fuelwood consumption runs 30- 200 per cent ahead of the average increase intrees, that Africa loses an estimated 5 millionhectares of tropical forest a year and that landdegradation is estimated to affect about 230 millionhectares annually (Nana-Sinkam, 1995). Asfor water resources per se, the growing demandfor water, the general diminution of atmospherichumidity and the environmental threats to climatevariations and change pose challenges tothe management of water resources and to meetingcompeting demands for basic water supplyand sanitation, for food security and for economicdevelopment in the continent.Rio Declaration of Environment and Development(1992):‘States shall cooperate in a spirit of global partnership to conserve,protect and restore the health and integrity of the Earth’s ecosystem.’Bonn Recommendations for Action (2001):‘Water governance arrangements should protect ecosystems andpreserve or restore the ecological integrity of groundwater, rivers,lakes, wetlands and associated coastal zones.’Environmental and land degradationDuring the past 30 years, a huge proportion ofAfrica’s land has been and yet more is beingconverted for agricultural use. By 1999, about202 million hectares (ha), nearly a third of it arable,was being cultivated. Many marginal areasor important natural habitats such as wetlandsand forests are being cleared, leaving the land increasinglyprone to erosion. About 25 per centof the land is now subject to water erosion andabout 22 per cent to wind erosion. Desertificationis currently affecting over 45 per cent of Africa,55 per cent of which is at high or very highrisk (UNEP GEO-3, 2002).One of the underlying causes of this situationis inadequate management of natural resourceson which a large part of the economy is based,especially in areas with high population densityand growth rates. In the tropical rain forest areasof the continent, for example, deforestation continuesat an alarming rate, leading to loss of productivity,of the irreplaceable biodiversity that isof immense benefit to the global gene bank andof the vegetation needed for balancing the earth’sclimate. The impact of this poor managementand conversion of land, including marginal areas,leading to increased runoff, erosion, sedimentationand ultimate loss of productivity is becomingincreasingly felt in areas with dense humansettlement and inadequate or inappropriate cul-Protecting Ecosystems in Africa125