The Role of Sustainable Land Management for Climate ... - CAADP

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production in Africa and other regions (Hulme et al. 2001; Christensen et al. 2007). However,
the importance of land-cover change in altering regional climate in Africa has long been
suggested (Hulme et al. 2001). Different studies indicate that vegetation patterns help shape the
climatic zones of Africa and, changes in vegetation result in alteration of surface properties and
the efficiency of ecosystem exchange of water, energy and CO 2 with the atmosphere
(Christensen et al. 2007). As a result of these limitations, available climate models might
underestimate the impacts of global warming in regions facing land degradation and reduction in
the vegetation cover.
Among the regions of the world, Sub-Saharan Africa has the highest rate of land
degradation (World Meteorological Organization (WMO) 2005). In Africa, land degradation
affects 67 percent of total land area with 25 percent characterized as severe and very severely
degraded and 4 to 7 percent as non-reclaimable. Some of the countries that have the worst rates
of soil degradation are: Rwanda and Burundi (57 percent), Burkina Faso (38 percent), Lesotho
(32 percent), Madagascar (31 percent), Togo and Nigeria (28 percent), Niger and South Africa
(27 percent) and Ethiopia (25 percent) (Bwalya et al. 2009). Defries (2002) estimates that land
cover change, such as continued deforestation expected to occur in the tropics and subtropics
will have a warming effect as a result of reduced carbon assimilation.
2.5 Impact of Climate Change on Agriculture and Food Security in Sub-
Saharan Africa
Sub-Saharan Africa is expected to face the largest challenges regarding food security as a result
of climate change and other drivers of global change (Easterling et al. 2007). Overall, Fischer et
al. (2005) estimate that as a result of climate change, agricultural GDP in Africa is expected to
fall by between -2 to -8 percent (HadCM3 and CGCM2) and -7 to -9 percent (CSIRO model)
(Fischer et al. 2005). Many farmers in Africa are likely to experience net revenue losses as a
result of climate change, particularly as a result of increased variability and extreme events.
Dryland farmers, especially the poorest ones, are expected to be severely affected.
Kurukulasuriya and Mendelsohn (2006) estimated that a 10 percent increase in temperature will
lead to a loss in net revenues per hectare, on average, of 8.2 percent for rainfed production. On
the other hand, irrigated farmers are likely to have slight gains in productivity (as higher
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