Main types of soil degradation in the Kura-Aras Lowland of Azerbaijan

The main types of soil degradation in the Kura-Aras Lowland are irrigation-induced erosion, natural water and wind erosion, and salinization. Among 2098.8 thousand ha of agricultural land in the lowland, the areas of lands subjected to erosion and salinization reach 333.6 and 373.4 thousand ha, respectively. The dependence of irrigation-induced erosion on the soil type (sierozems, meadow sierozems, and gray-cinnamonic soils), the inclination of the irrigation furrows, the irrigation water salinity (0.15-0.95 g/L), and the water discharge (0.8-1.4 L/s) was studied. It was found that soil erosion and salinization result in changes in the soil bulk density and porosity and in a decreasing content of humus and nutrients. Certain changes take place in the soil texture. The land areas subjected to rainstorm erosion of strong, moderate, and low degrees are estimated at 57.7, 24.4, and 15.3 thousand ha, respectively. Measures to control soil erosion and salinization are discussed.