用分布式水文模型识别流域冰川融水对径流的贡献——以天山库玛拉克河为例  

Estimation of glacier melt contribution to streamflow using a distributed hydrologic model for the Kumaric River,Tien Shan

作　　者：王晓蕾[1,2] 孙林[1] 张宜清[1,2] 罗毅[1] 

机构地区：[1]中国科学院地理科学与资源研究所,北京100101 [2]中国科学院大学,北京100049

出　　处：《资源科学》2015年第3期475-484,共10页Resources Science

基　　金：国家国际科技合作计划项目(编号:2010DFA92720);国家自然科学基金重点项目(编号:41130641)

摘　　要：高寒山区可能不同程度地覆盖冰川,从而对发育于此的河川径流产生贡献。估算冰川融水对河川径流贡献率在水文学、气候变化对雪冰流域影响以及雪冰流域水资源管理各方面均具有重要意义。由于高寒山区流域地形、冰川复杂,检测困难,定量冰川融水对河川径流的贡献率一直是个难题。本文尝试采用具有降雨、积雪、冰川水文过程模拟能力的分布式水文模型模拟流域产流过程和径流过程,以冰川融水及冰融水产流量占河川径流的比例来近似代替对径流的贡献率。在天山库玛拉克河流域的应用结果表明:1961-2007年库玛拉克河流域冰川融水及冰融水对河川径流的贡献率分别为53%和27%,且补给主要在夏季(6-8月)。根据1961-2007年的气象数据和模拟结果,随着气温和降水的变化,冰川融水及冰融水对径流贡献率均呈略微上升趋势,且冰融水与降水有较好的负相关性,在降水较少年代对径流具有重要"补偿"作用。Alpine watersheds often feed their streams through glacier and snow melt water. Glacier and snow melt contribution to streamflow is of importance due to their roles in regulating streamflow over seasonal and decadal scales and because of sensitive responses to climate change.Estimation of glacier and snow melt contribution to streamflow is challenged by insufficient observation data of melt at the basin scale,except at a few experimental glaciers around the world.Here,we attempted to estimate the glacial and snow melt contribution to streamflow using a distributed hydrological model(SWAT-RSG model)capable of simulating glacier and snow melt at the watershed scale. This method can differentiate glacier,ice and snow melts over the basin scale and at daily time steps. Results in a glacier melt-dominated catchment of the Kumaric River,South Tien Shan proved successful. Contribution ratios of glacier melt and ice melt to river discharge was estimated as 53% and 27%,respectively. Seasonal change patterns and inter-annual variation in contribution ratios were also analyzed. The glacier meltwater fed streamflow mainly in summer and contributions of glacier melt and ice melt represented non-significant upward trends from 1961 to 2007. Moreover,ice meltwater was negatively correlated with precipitation and a‘compensation effect'throughout the dry season mitigating the impact of meteorological runoff deficits. Our work lays a critical theoretical basis for future estimations of glacier-melt contribution to streamflow.

关 键 词：分布式水文模型 库玛拉克河 冰川融水 冰融水 径流 贡献率 

分 类 号：P343.6[天文地球—水文科学] P333[天文地球—地球物理学]