近66 a来淮河干流水沙变化特征分析

为了分析淮河干流水沙变化特征,选定吴家渡水文站为代表性水文站,采用累积距平、M-K分析法、R/S分析法和Morlet小波分析法等方法,对吴家渡站1950—2015年水沙实测资料进行分析,研究淮河干流近66 a来水沙序列变化趋势、突变点及周期特征,并深入分析水沙条件突变及变化趋势的真实原因。结果显示:整体上淮河干流年径流量未呈现明显的增加或减小的趋势,但淮河干流来沙量则表现出明显的减少趋势,2000年后来沙量趋于稳定;淮河干流来沙变化具有较明显的阶段性特征,整体上呈现出多、少2个阶段的变化过程,发生突变的年份在1980—1984年之间,未来一段时间来沙量整体呈现减小的趋势;水库拦沙、农业种植改变下垫面、人工采砂及航道整治与河道疏浚的作用是导致淮河干流含沙量持续减小的原因;径流量第1—第3主周期分别为18,8,2 a,并且在未来短时间内将继续保持枯水期;输沙量整体上保持减少的趋势,第1—第4主周期分别为7,17,25,2 a,含沙量的第1和第2主周期分别为23,6 a,并且在未来短时间内将继续保持少沙期。研究成果可为淮河流域水资源管理与河道治理开发利用提供理论依据。

Susceptibility and Periodicity of Water and Sediment Characteristics of Mainstream Huaihe River in Recent 66 Years

The trends of water and sediment, abrupt change point, and periodic features of mainstream Huaihe River in the recent 66 years were examined via cumulative anomaly, M-K test, R/S analysis and wavelet analysis. The observed water and sediment data during 1950-2015 at Wujiadu hydrological station, a typical station, was analyzed. The real causes of abrupt changes and change trends were researched in depth as well. In general, the annual runoff of mainstream Huaihe River did not undergo obvious increase or decrease; yet the incoming sediment displayed a remarkable declining trend until 2000, after which the incoming sediment tended to be stable. The fluctuation of incoming sediment experienced two stages from large to small incoming, with the abrupt change happening during 1980-1984. Such decrement trend will last in the near future. The causes of such decrement of incoming sediment lie in reservoir blocking, agricultural plantation, artificial sand mining, navigation channel regulation, and river channel dredging. What’s more, the first, second, and third dominant periods of runoff are 18 a, 8 a, and 2 a, respectively; and in the near future low flow will continue; on the other hand, sediment discharge remained declining in general, with the dominant periods of 7 a, 17 a, 25 a, and 2 a; sediment concentration will also remain small in the near future, with its dominant periods of 23 a and 6 a. The research findings offer theoretical basis for the water resource management and channel exploitation of Huaihe River Basin.