黄河三花间年径流量变化规律

Variation patterns of annual runoff in Sanhuajian basin of Yellow River

利用1956—2007年黄河中游三门峡-花园口区间(简称"三花间"区)4个水文站的实测年径流量资料,采用趋势分析、小波分析等统计方法,探讨了三花间区年径流量的变化特征。结果表明:三花间年径流量的总体变化呈减少趋势;年径流量大体上经历了2个丰水阶段和2个枯水阶段的交替变化,转折点出现在1969、1982和1987年;年径流量的时频变化则以25a或2～8a的周期变化为主。

Based the 1956-2007 annual runoff data from four hydrological stations in the middle reaches of Yellow River from Sanmenxia to Huayuankou（Sanhuajian basin）,and by using the statistical methods of trend analysis and wavelet transform,this paper studied the variation characteristics of annual runoff in the basin.There was a distinct decreasing trend of the annual runoff in the basin.On the whole,the annual runoff experienced an alternation of two wet and two dry periods,whose turn points occurred at 1969,1982,and 1987.The time-frequency variation of the annual runoff was mainly a 25-year cycle or a 2-8-year cycle.