| Abstract: | The Gloldnaya steppe has large areas of fertile sierozem soils that are important for crop production and its accompanying economic development. The soils are fertile loams, but because of the steppe's dry environment, they need to be irrigated. Our objective was to study irrigation management of cotton production on sierozem soils in southern Kazakhstan. From 2006 to 2008, we grew irrigated cotton on low, moderately, and highly saline sierozem soils in the South Kazakhstan Oblast. Soils were irrigated to reduce salinity and improve growth. Yields increased with reduced salinity especially because the highly saline soil could not support growth every year and because it had 33 to 40% less yield when cotton was grown on it. Soils were managed with multiple tillage and cultivations by machinery and hand, which maintained low bulk densities near the surface and a tillage pan at about the 30-cm depth. Future management improvements include fewer tillage operations, which would decrease energy needs and compaction. Reduced upstream salinity would reduce preplanting irrigation needs. |
