[关键词]
[摘要]
为探明黄河石嘴山站的来水来沙过程,便于海勃湾水库的水沙调度,根据1951-2016年的水沙数据,采用非线性统计等方法分析了黄河石嘴山站的水沙序列变化及发展趋势。结果表明:石嘴山站水沙年内分配不均匀,20世纪60年代变化剧烈;66 a来年径流量与年输沙量均呈显著性减少趋势,且具有正持续性,持续影响时间约8 a、10 a;水沙序列分别于1986年、1968年发生突变,突变原因与黄河上游大型水库的运用密切相关;龙羊峡、刘家峡水库分别对径流和泥沙的影响显著,二者联合运用后,石嘴山站流量基本处于2 000 m3/s以下,水沙分配趋于均匀;不同时期的水沙关系重新调整,但均不显著;石嘴山站多年平均含沙量及多年平均来沙系数均较刘家峡水库运用前明显降低,但在龙、刘两水库联合运用后基本不变。
[Key word]
[Abstract]
In order to explore the water and sediment processes at the Shizuishan hydrologic station in the Yellow River and to provide information for the Haibowan reservoir management,nonlinear statistical techniques were used to investigate the water and sediment changes from 1951 to 2016.The results showed that the temporal distributions of water and sediment at the Shizuishan station was uneven,and the changes during the 1960s were larger.Both annual runoff and annual sediment discharges showed statistically significant decreasing trends,which had a positive continuity and lasted for about 8 and 10 years.The step-changes of streamflow and sediment discharge occurred in 1986 and 1968,respectively,and the main reason for these changes was the coustruction of large reservoirs in the upper reaches of the Yellow River.Both reservoirs had significant impacts on streamflow and sediment discharge,and the streamflow discharge was always below 2 000m3/s after the operations of these two reservoirs.The intraannual and interannual distributions of streamflow and sediment discharges were also tended to be even.The relationship between water and sediment was re-adjusted in different periods,although its adjustment magnitude was minor.The average annual sediment concentration and average incoming sediment coefficient were significantly lower after the operation of Liujiaxia reservoir,but remained almost the same after the operations of Long and Liu reservoirs.
[中图分类号]
[基金项目]
国家重点研发计划(2018YFC1508401);[JP2]2018内蒙古自治区应用技术研究与开发资金项目(201802104);国家自然科学基金(51569020)