1964—2012年艾比湖流域径流变化特征分析

Runoff Variation Characteristics in Ebinur Lake Basin During 1964-2012

为了更好地剖析艾比湖流域径流的演变特征,笔者根据艾比湖流域3个水文站1964—2012年近50年的监测数据,以不均匀系数、集中度、变化幅度为指标,阐释了1964—2012年艾比湖流域径流变化规律。结果表明:(1)随着时间的推移,精河、博尔塔拉河的年径流量在1964—2012年间均呈"减少—增加—减少"的演变趋势,总体上,1964—1976年间呈缓慢减少趋势,1977—2002年间呈增加趋势,2003—2012年间呈减少趋势。从季节变化来看,径流主要集中在夏季,最少的径流量发生在春季;(2)一年中精河径流波动幅度越来越大,博尔塔拉河流则呈相反的变化。(3)从整体的角度来看,博尔塔拉河和精河在一年内径流分配绝对变化幅度趋势呈"山谷形",即先降低后上升,但同时相对变化幅度会持续降低,充分揭示出精河与博尔塔拉河在一年中各径流分配的变化逐渐倾向于均匀化的现实。

The paper aims to analyze the variation characteristics of runoff in Ebinur Lake Basin, the variationlaw of runoff in Ebnur Lake was studied based on the observed monthly runoff of three key hydrological controlstations during 1964-2012, and by using indexes such as non-uniformity coefficient, concentration degree andvariation amplitude. The results indicated that：（1） the changing trend of annual runoff in Ebnur Lake Basinwas＂decrease-increase-decrease＂, as a whole, it decreased slowly during 1964-1976, increased during 1977-2002, decreased during 2003-2012; the runoff was mainly concentrated in summer while it was the least inspring;（2） as time went on, the non-uniformity and concentration degree of annual runoff distribution of JingheRiver increased and that of Bortala River decreased;（3） the absolutely variation amplitude of annual runoffdistribution of Jinghe River and Bortala River decreased at first, then increased with the time while therelatively variation amplitude of annual runoff distribution had a continuous decreasing trend.