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3 What t c a p Im ave? tion H a c i f i t r e s e D Does Because people, who live in drylands, depend on the ecosystem services for their crops, livestock, commodities, fuel wood, etc., deterioration in ecosystem services by land degradation triggers further degradation of their livelihood and well-being. Both short-term and long-term climatic variations create instability in the production of crops, forage, livestock, and also the water supply. Once a dryland ecosystem is damaged, even the removal of the cause cannot ensure full recovery of the ecosystem. The well-being of the population is trapped in a vicious spiral of decreased agricultural productivity and increased poverty. Many African countries often have serious droughts. As the land which is basis for food production is degraded, local people have no choice but to exploit further natural resources such as forests and water. This leads to further land degradation to create a downward spiral. ▼ Consequences of Desertification Undermining basis of food production Acceleration of poverty Population concentration in urban areas Increased refugees Loss of biodiversity Impact on climate change ▼ Human Activities and Dryland Degradation Human Factors: Political, economic, socio-political and scientific and technology Political and economic instability Overgrazing and expansion of cropped areas ▼ Population Affected by Desertification Reduced vegetation cover Large-scale expansion of irrigation Increased soil erosion Salinization Global population 6.51 billion People at risk to be affected 1 billion Climatological factors People directly affected 250 million Reduced biological productivity Climate change, Drought 0 5 10 15 20 25 30 Source: UNCCD Fact Sheet(2005) ※ Population figures taken from ‘United Nations World Population Prospects: The 2006 Revision. 60 65 70 Poverty, emigration, and reduced human well-being (100 million people) Source: Millennium Ecosystem Assessment(2005) ▼ Linkages and Feedback Loops among Desertification, Global Climate Change and Biodiversity Loss Desertification Reduced carbon sequestration into above- and below- ground carbon reserves Decreased plant and soil organisms’ species diversity The left hand side of the figure shows the complex interaction between desertification, climate change and biodiversity loss. Reduced primary production and nutrient cycling Desertification is not only the result of climate change, but also influences climate change by Reduced soil conservation reducing carbon sequestration of vegetation and soil. Increase in extreme events(floods, droughts, fires…) Soil erosion Diversity in vegetation in dryland Reduced structural diversity of vegetation cover and diversity of microbial species in soil crust Reduced carbon reserves and increased CO2 emissions ecosystem supports livestock and wildlife as well as people through provision of food and fuel. This important function of biodiversity is being damaged as a result of desertification. Loss of nutrients and soil moisture Climate change Biodiversity loss Increases and reductions in species abundances Major services impacted by biodiversity losses Change in community structure and diversity Major components of biodiversity involved in the linkages Source: Millennium Ecosystem Assessment(2005)