疏勒河上游径流组分及其变化特征定量模拟

气候变化背景下，西北干旱区内陆河流域的水文过程发生显著变化，制约着地区经济社会和生态建设的稳定发展。定量分析和评估高寒山区径流的变化，有助于加强西北地区水资源的规划管理，实现水资源的可持续利用，保障区域水安全。选取位于青藏高原东北边缘、祁连山西段的疏勒河上游作为研究区，利用包含冰雪消融模块的寒区水文模型分布式SPHY模型（Spatial Processes inHydrology model）对流域的径流过程进行定量模拟，根据模拟结果分析了疏勒河上游近45 a径流组成及径流与各组分的变化特征。结果表明：（1）率定期日径流和月径流模拟的Nash效率系数分别为0.62和0.86，验证期达到0.79和0.95，模拟的月径流与实测月径流过程基本一致；（2）径流由四部分组成，冰川径流占总径流的年平均比例为30.5%，融雪径流的占比为12.9%，降雨径流的占比为13.5%，基流的占比为43.1%；（3）由于气温升高、降水增多，冰川径流与降雨径流均呈增加的趋势，平均增加幅度分别为4.66×10⁶ m³·a^-1和2.46×10⁶ m³·a^-1，融雪径流呈减少的趋势，平均减少幅度为1.01×10⁶ m³·a^-1；（4）近45 a年径流增加了69.6%，冰川融水对流域径流增加的贡献率达到48%，非冰川区降水增加的贡献率达到52%。

Quantitative simulation of the runoff components and its variation characteristics in the upstream of the Shule River

The hydrological process of inland river basins in the arid area of Northwest China has changed significantly under climate change,which restricts the stable development of regional economic society and ecological construction. Quantitative analysis and evaluation the change of runoff in the alpine area will help to strengthen the planning and management of water resources in the Northwest China,to realize the sustainable utilization of water resources and ensure regional water security. Using a fully distributed,high-resolution cryospheric-hydrological model called SPHY model to simulate runoff process in the upstream of the Shule River,which located in the northeast edge of the Tibetan Plateau and the western of Qilian Mountains. According to the simulation results,the characteristics of runoff composition and the variation of runoff and its components in the upstream of the Shule River were analyzed. Results show that:(1)the Nash-Sutcliffe efficiency coefficients of daily runoff and monthly runoff in calibration period(1971-2008)were 0.62 and 0.86,respectively,and in the validation period(2009-2015)were 0.79 and 0.95,and the simulated monthly runoff process was in accordance with the measured monthly runoff process. (2)The runoff was composed of four parts,of which the glacier melt runoff and snowmelt runoff accounted for an annual average proportion of 30.5% and 12.9% to the total runoff, and the proportion of rainfall runoff and baseflow was 13.5% and 43.1%,respectively. (3)Due to increasing in temperature and precipitation,both the glacier runoff and rainfall runoff are increasing,with an average increase rate of 4.66×106 m³·a^-1 and 2.46×106 m³·a^-1,respectively. Snowmelt runoff showed a decreasing trend,with an average reduction rate of 1.01×106 m³·a^-1. (4)The annual runoff has increased by 69.6% over the past 45 years,with the contribution rate of glacier meltwater to increase in runoff of 48%,and the contribution rate of precipitation in non-glacierized area of 52%.