黄河下游水沙变化特点

本文以黄河下游河段小浪底、花园口、高村、艾山、利津水文站1950—2016年水沙资料为研究对象,通过实测资料分析与理论分析对黄河下游水沙特点进行研究。结果表明:近70年来黄河下游沿程各水文站年水沙量整体上呈现减小的趋势;水沙年际间、年内分配不均匀;1986年后下游水沙关系明显恶化,2003年后水沙关系又得到明显改善;近年来黄河下游大流量减少,小流量增多,输水输沙主要集中在1000~4000m~3/s洪水中;确定保证下游微淤甚至冲刷的来沙系数应不超过0.01kg·s/m~6。分析黄河水沙变化特点,掌握其变化规律可为缓减黄河下游水沙关系,完善治黄方略提供条件。

Characteristics of water and sediment variation in the lower reaches of the Yellow River

In this paper,the water and sediment data of Xiaolangdi,Huayuankou,Gaocun,Ai Shan and Lijin hydrological stations in the lower reaches of the Yellow River from 1950 to 2016,are taken as the research objects.The characteristics of water and sediment in the lower reaches of the Yellow River are studied through the analysis of measured data and theoretical analysis.The results show that in recent 70 years,the annual water and sediment volume of each hydrological station along the lower reaches of the Yellow River has shown a decreasing trend as a whole;Uneven distribution of water and sediment between years and within years.After 1986,the relationship between water and sediment in the lower reaches deteriorated obviously.And after 2003,the relationship was improved obviously.In recent years,the large discharge decreases and the small discharge increases in the lower reaches of the Yellow River,and the water and sediment transport is mainly concentrated in the flood of 1000~4000m 3/s.It is determined that the sediment inflow coefficient to ensure the downstream micro-silting and even scouring should not exceed 0.01kg·s/m 6.Analyzing the variation characteristics of water and sediment in the Yellow River and mastering its variation law can provide conditions for slowing down the deterioration of water and sediment in the lower reaches of the Yellow River and improving the strategy of harnessing the Yellow River.