近50年来疏勒河上游气候变化及其对地表径流的影响

Climate Change in Upstream Area of Shule River and Its Effects on Runoff-yield in Last 50 Years

以1961—2010年疏勒河上游山区气温、降水和径流数据为基础,采用Mann—Kendall和R/S分析法,在年、季节尺度上研究了气温、降水和径流的变化特征,并采用多元线性回归分析法揭示了径流变化的主控因素。研究结果表明,近50a来研究区年均气温上升趋势显著且持续性极强。20世纪60—70年代气温偏低,1986年以后快速上升,并在1990年左右发生暖突变。降水量在研究时段内增加趋势明显且持续性较强。20世纪60—70年代降水偏少,80年代开始偏多,90年代偏少,1998年左右发生由少到多的突变。研究区气候在20世纪80年代中期由暖干向暖湿转型,受气候变化影响上游地区径流量显著增加,其年际和季节变化特征与降水变化相似。冬季和秋季径流变化主要受地下水影响,而春季和夏季径流变化主要受降水和冰雪融水的控制。

The seasonal and annual variation characteristics of air temperature and precipitation as well as run- off-yield in the upstream area of Shule River were analyzed based on meteorological and hydrological data during 1961--2010 by using Mann Kendall test and R/S analysis. Linear multi-regression of monthly runoff model was used to evaluate effects of temperature and precipitation in runoff-yield. The results showed that the annual mean temperature had risen very significantly with very strong persistency since 1960s. It is low from 1960s to 1970s and increased fast after 1986. The climatic warming had accelerated after temperature mutation in 1990. The annual precipitation presented a very significantly increasing tendency with strong persistency in the studied period and the fluctuation of annual precipitation was quite obvious. It experienced a changing trend that was lower（the 1960s and 1970s）--higher（the 1980s）--lower（the 1990s）--higher（after 2000）. The strong signals of climatic shift to warm humid pattern appeared since mid-1980s and runoff-yield increased very significantly due to climatic mutation. The annual and seasonal variation characteristics of runoff-yield were consistent with precipitation. The runoff-yield was mainly affected by underground water in winter and autumn, and was controlled by precipitation and ice-snow melt water in spring and summer.