黄河宁蒙河段水沙调控指标

Regulation indicators of water and sediment in the Ningxia-Inner Mongolia Reach of the Yellow River

1986年以后黄河宁蒙河段河道严重淤积萎缩,防凌防洪形势严峻。采用调水调沙减少河道淤积、改善河道形态是未来宁蒙河道治理的重要措施。通过理论与实测资料分析,研究提高河道泥沙输移效率、减少河道淤积、恢复与维持中水河槽,提出了上游水库对宁蒙河段进行调水调沙的调控流量、调控历时、调控时机等水沙调控指标。进入宁蒙河段的水沙调控流量宜控制在2500~3000 m^3/s;一次流量过程的调控历时应不小于15天,维持年内冲淤平衡的大流量宜不小于30天;适应宁蒙河段干支流洪水泥沙特点,水沙调控时机应安排在7月中旬至9月下旬,7月中旬至8月下旬是宁蒙河段支流高含沙洪水频发期,应泄放大流量稀释支流高含沙洪水,防止淤堵干流河道。

Sediment deposition in the Ningxia-Inner Mongolia reached severe shrinkage,and the situation of flood prevention and flood control were severe after 1986.Reducing sediment deposition and improving the shape of the river through water and sediment regulation are important for the river governance of the NingxiaInner Mongolia reach in the future.By the theoretical analysis and measured data,the research was carried out from the perspective of improving the efficiency of river sediment transport,reducing channel deposition,restore and maintain the median water channel,and proposed water and sediment regulation indicators of the upstream reservoir for water and sediment regulation in the Ningxia-Inner Mongolia reach,such as the regulation of the flow,regulation duration and regulation duration.The regulation and control flow of water and sediment into the river of the Ningxia-Inner Mongolia reach should be controlled at 2,500 m^3/s-3,000 m^3/s.The regulation and control of one flow processes should be larger than 15 days and the high flow should be in 30 days to maintain the balance of deposition and scour.According to the characteristics of the water flow and sediment in the main river channel and tributary of the reach,the water and sediment regulation should be arranged in the upstream from mid-July to late September.From mid-July to late August is the frequent occurrence of highsediment flood in the tributaries of the Ningxia-Inner Mongolia reach when the discharged volume should be increased with dilute tributaries with high-sediment floods to prevent blockage in main rivers.