雅砻江上游径流及影响因素关系研究

为研究雅砻江上游径流的变化及其积雪、气温和降水对径流的影响，首先根据相关性将年径流周期分为枯水期、融雪影响期和汛期，其次，结合MODIS 8天积雪产品、研究区气温和降水数据，采用相关分析和归因分析法分析了径流与影响因素的相关性以及各影响因素对径流变化的影响程度，最后用逐步多元回归分析法得出枯水期和融雪影响期径流的预测方程。结果表明：2000-2014年间雅砻江上游径流整体呈上升趋势，冬季积雪面积的减少导致径流减少了24.89%，汛期降水增加导致径流增加了79.38%，采用相关分析和逐步多元回归方法可有效分析径流与影响因素的关系及影响程度。

Runoff and its influencing factors in the upper reaches of the Yalong River

This paper is mainly devoted to the analysis of the runoff and its influencing factors in the upper reaches of the Yalong River,Sichuan Province,China based on correlation analysis and multivariate regression method. Firstly,we divided the annual runoff cycle into the drought period,snowmelt-affecting period and runoff-falling period based on the correlation analysis. With MODIS 8d snow-cover products,and the air temperature data and rainfall data in the study area,the correlation between the runoff and its influencing factors as well as the influencing degree of each factor to the change of the runoff were then analyzed using correlation analysis and attribution analysis.Finally,a runoff prediction equation in the drought period and the snowmelt-affecting period was concluded using the method of stepwise multivariate regression.The results showed that from an overall perspective the runoff in the upper reaches of the Yalong River was on the rise from 2000 to 2014.It was dropped by 24.89% due to the reduction of snow cover in the drought period yet it was increased by 79.38% because of the rainfall in the runoff-falling period. The method developed in this paper can be used effectively to analyze the correlation between the runoff and its influencing factors and to understand the influential degree of each factor.