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揭皮沟流域属渭河上的一级支沟。多年来共建各类坝库56座。建坝密度为0．51座/km~2。骨干坝与淤地坝配置比例为1：2．7。结果表明：通过坝系建设,防洪能力提高,可防御2%频率的洪水。坝系工程初步实现了流域水沙的利用平衡。同时,保收面积和保收能力逐年增加。以往研究表明,在各项水土保持措施中,淤地坝对于入黄泥沙减少的贡献率远远高于其他措施；造林的贡献率居第2位,梯田的贡献率居第3位,种草的贡献率则最小。黄土高原沟壑面积占总面积的40%～60%,为淤地坝的发展提供了基本的条件。今后尚可新建控制性的治沟骨干工程2万多座,新建淤地坝13万座,涉及七省(区)32条主要支流。据初步预测,可累计拦蓄泥沙259亿 m~3,新增坝地3333km~2,加上已有坝地,将达到6667km~2,届时坝地成为黄土高原区主要的粮食生产基地。
Belt furighed basin is a branch of the Weihe River. Over the years to build various types of dam 56. Dam density of 0.51 blocks / km ~ 2. The ratio of the main dam and the check dam is 1: 2.7. The results show that through the dam system construction, flood control capability can be improved to prevent floods of 2% frequency. The dam system has basically realized the utilization balance of water and sediment in the basin. At the same time, the area of acceptance and the capacity to keep increasing year by year. Previous studies show that in all water and soil conservation measures, the contribution of silt dams to the reduction of sediment into the Yellow River is much higher than other measures; the contribution rate of afforestation ranks second, and the contribution of terraces ranks third Grass contribution rate is the smallest. The gully area of the Loess Plateau accounts for 40% -60% of the total area, providing the basic conditions for the development of silt dam. In the future, it will be possible to newly build more than 20,000 controlled trench rehabilitation projects and build 130,000 silt dam projects involving 32 major tributaries of seven provinces (districts). According to the preliminary forecast, it can accumulate a total of 25.9 billion m 3 of sediment and 3333 km -2 of newly added dam land. In addition, the existing dam land will reach 6667 km 2, and the dam land will become the major grain production base in the Loess Plateau.