长江上游枯水期及10月径流情势分析

采用非参数统计检验Mann-Kendal法分析了长江上游寸滩、宜昌站枯水期及10月的流量变化趋势,并用有序聚类分析法分析了两站枯水期及10月流量序列的跳跃点.结果表明:两站枯水期流量均呈上升趋势,10月流量均呈下降趋势;两站枯水期流量序列的跳跃点均为1989年,10月流量序列的跳跃点均为1991年.枯水期和10月流量序列的跳跃点基本吻合,初步判定,跳跃点的产生可能是由于长江上游流域水库运行引起的.

Runoff regimes of upstream Yangtze River in dry season and October

The Mann-Kendal statistical test method was employed to analyze the trend of runoff variation at Cuntan and Yichang hydrological stations in dry season and October. The break points of the runoff series at the two hydrological stations in dry season and October were discussed by use of the ordered clustering analysis method. The results show that the runoff series at the two stations exhibit an increasing trend in the dry season and a decreasing trend in October. In the dry season, the runoff series at the two stations both have break points in 1989, and in October, they both have break points in 1991. The break points of the runoff series in the dry season agree with those in October. It is preliminarily judged that the break points are probably caused by the operation of reservoirs in the upper reaches of Yangtze River.