新疆开垦河流域径流变化特征分析

Analysis on Runoff Variation Characteristics of Kaiken River Basin in Xinjiang

根据新疆开垦河水文站的多年实测径流资料,利用方差分析法、回归分析法和Mann-Kendall秩次检验法等,分析了开垦河径流的分配和年际变化的特征。结果表明:开垦河径流年内分配较均匀;43 a的径流统计中,83.7%的年份径流集中度>50%,表明径流补给来源以雨水和高山冰雪(季节性积雪)融水为主。季节性积雪融水量占高山冰雪融水量和雨水量总和的比重在逐年增加。流域径流量主要集中在汛期(4-9月),最大径流量出现在6月,且汛期径流量占年径流量的比重逐渐增加。同时,春季径流量高于冬季。径流量年际变化平缓,呈微弱上升趋势,年径流变差系数仅为0.23;径流量代际变化特征明显,20世纪80年代由枯水期转向丰水期,但未发生突变;流域年径流量有较明显的周期成分,其显著周期为3,14,16,19 a。

According to gauging discharge of the representative hydrologic station which lies in the exit of Kaiken River in Xinjiang,this paper analyzes both distribution and variation characteristics over years of runoff,using variance analysis,regression analysis and Mann-Kendall test.The results show that the intra-annual distribution of runoff comparatively even with 83.7% of years＇ concentration degree is above 50%,which indicates that the main supply sources of runoff are rainwater and thawy water from glacier（seasonal snow）.On the one hand,the runoff volume mainly concentrates in the flood season （April to September） with the largest volume appears in June,at the same time,the runoff volume in spring is more than that in winter.While on the other,the variation coefficient over years is only 0.23 with relative stable runoff volume change.On the contrary,the phasical change of the runoff volume is significant,in 1980s,the Kaiken River turns from low water to high water but without sudden mutation.The annual runoff has significant periodicity and its notable periods are 3 a,14 a,16 a,19 a.