Water and Sediment Variations of Huanjiang River Basin in 1990s and Discussion on Its Controlling Methods

Based on surveyed hydrologic data, the water and sediment variations in 1990s (from 1990 to 2000) of Huanjiang river basin were deeply analyzed and studied, which is the second level branches of Jinghe river. Taking three methods, the reduction benefits of flood and sediment by integrative measures were calculated, the variation of the underground water supply was analyzed, the utilization rate of the surface water resources in basin was estimated, and the general plan of exploring of water resources and controlling of Huanjiang river basin was discussed. The results showed that since 1990 the maximum precipitation in 24 hours had increased evidently, runoff and sediment had increased by a big margin, and the effective precipitation per mm contributing to flood and sediment had been the highest in four periods. The roles for reduction of flood and sediment by integrative measures reduced, the underground water supply increased, and the utilization rate of surface water was low. Accordingly, a general plan of integrative control was given, which can be used to consult for the eco environment construction of soil and water conservation in Huanjiang river basin.