西天山某流域积雪变化及其与径流量相关性分析

Snow Cover Change and Its Correlation Analysis with Runoff in A River Basin in West Tianshan

基于2004—2020年MODIS积雪资料和实测流量资料,分析西天山A河流域年际年内积雪覆盖率(全流域和7个分带)、雪线高度的变化特征,及其与径流量的相关关系。结果表明:各高程分带积雪覆盖率随海拔的升高不断增大,且海拔越低积雪融化时间越早,开始累积时间越滞后。不同高程分带积雪覆盖率、雪线高度与次年径流量线性相关,分析发现海拔2500~3500 m积雪对次年径流量的贡献最大,与月均流量幂相关,相关系数均在0.64以上。各积雪要素与次年径流量、月均流量之间的多元回归方程分别通过0.1、0.01的显著性水平检验。

Based on MODIS snow cover observations and local runoff data from 2004 to 2020,the characteristics of annual snow cover change and snow line height variations were studied,and their relationship with runoff was analyzed in a river basin in west Tianshan Mountains.For different elevation zones,the results show that the snow cover rate increases with the elevation.The lower the elevation,the earlier the snow melts and the later the accumulation starts.There is a linear correlation between snow coverage of each zone and snow line height or runoff in the next year.And the contribution of snow cover to runoff at 2500-3500 m height is the largest.It has a power correlation with monthly run⁃off,with correlation coefficients all above 0.64.The multiple regression equations between snow cover factors and the next year runoff or monthly runoff pass the significance level test of 0.1 and 0.01,respectively.