ARS | Publication request: ASSESSING THE EFFECT OF BEST MANAGEMENT PRACTICES ON THE ARAL SEA WATER RESOURCES AND EROSION WITH THE WEPP MODEL

Submitted to: USA/Commonwealth of Independent States Joint Conference on Environmental Hy
Publication Type: Abstract Only
Publication Acceptance Date: October 10, 1996
Publication Date: N/A

Technical Abstract: The Aral Sea surface area shrank from 67,400 square kilometers in 1961 to 40,390 square kilometers in 1989. The average annual water level of the sea has decreased from 53 to 39 meters (above Baltic Sea) during this period. Upstream diversion of the two main rivers which flow to the Aral Sea, Amu Darya and Syr Darya, for irrigation purposes, resulted in a significant reduction of the amount of water reaching the sea. Most of the scientist in the region and/or world community have come to the realization that the Aral Sea cannot be the same level as 1960. It has been estimated that the irrigation needs to be seized for the next 25 years, if the Aral Sea should ever recover totally. This is a very unlikely solution. Therefore, the only reasonable solution to the Aral Sea basin water crisis is the use of better water conservation methods and the improvement of irrigation efficiency. We had used three steps to evaluate the implications of Best Management Practices (BMP) on water resources and erosion of the irrigated farms within the Aral Sea basin: a) develop quantitative scenarios of changes in agricultural practices, such as tillage, residue management, buffer strip and soil amendments; b) using the WEPP model to simulate the water balance, crop yield, and soil erosion of the farms given the established scenarios, and c) assess the implications of different management systems on the crop yield, surface runoff, soil water content soil erosion. The results indicate that management practices such as crop residue management and/or increase of soil organic matter can be utilized to improve soil water holding capacities of sandy loam soils in Uzbakistan, and therefore, improve water use efficiency of irrigated cotton farms in the area.