Central Asia comprises a wide range of soils (Sommer and DePauw, 2011) and agro-ecological zones (De Pauw, 2010). This isnot surprising given the dimensions of Central Asia measuringabout 2000 km north-south (35 N to 55◦N) and almost 2900 kmeast-west (46◦E to 87◦E). Coverage of a wide range of altitudes(50–7500 m above sea level) adds to the complex set of agroecologicalzones. Furthermore, the regional differences in termsof dependency on irrigation water for agriculture are large. About22% (85 Mha) of the total geographic area of Central Asia is undercultivation, whereas roughly 30% of this cultivated land is underirrigation (Celis et al., 2007). Uzbekistan almost fully relies on irrigatedagriculture (>80% of the cultivated land), while percent-wise,Kazakhstan has the smallest share of the five countries (<13%).Furthermore, especially Uzbekistan, but also partly the other fourCentral Asian countries, suffer from land degradation by secondarysoil salinization in response to suboptimal irrigation/drainage managementand shallow, saline groundwater levels.
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