金沙江流域近60年气候变化趋势及径流响应关系

Trend of Climate Change over the Recent 60 Years and its Hydrological Responses for Jinsha River Basin

以长江上游金沙江流域为研究对象,采用线性回归法和Mann-Kendall非参数检验法诊断了近60年来金沙江流域气温、降水、径流的演变趋势以及径流对气候要素变化的响应关系。结果表明:1金沙江流域的气温具有显著的升高趋势,年均气温线性增加率为0.025 2℃/a,其中,冬季升温最为显著;2降水量呈现明显的丰枯年交替的演变规律,尽管年降水量总体上具有非显著性增加趋势(M-K值为1.48),但秋季降水量呈现弱减少趋势;3受降水、气温、积雪和冰川等因素变化的影响,金沙江流域的流量总体上呈增加趋势,然而,近20年具有明显的减少趋势;4年和季节降水量与径流具有较好的正相关性,尽管年气温与流量具有不显著的负相关性,但由于气温和降水的季节同步性,季节气温与径流呈现出较好的正相关性。

Taking the Jinsha River Basin as a study area,the variation trends of temperature,precipitation,runoff over the recent 60 years were detected by using linear regression and Mann-Kendall test,and hydrological responses to climate change were investigated at different temporal scales. The results show: 1 The annual temperature in Jinsha River has a significant rising trend with a linear rising rate of 0. 025 2 ℃ / a and the most significant rising occurs in winter; 2 The annual precipitation exhibits an alternative occurrence of wet and dry. Although an insignificant increasing trend is detected with the M-K value of 1. 48,but the seasonal precipitations in general have an increasing trend with exception of autumn precipitation; 3 Affected by changes in precipitation,temperature,snow and glaciers and other factors,the flow rate in Jinsha River Watershed increased generally,however,the past 20 years has a significant decreasing trend; 4 The annual and seasonal precipitation and runoff have good positive correlation. Although the annual temperature and flow rate have no significant negative correlation,but because of the seasonal synchronization of temperature and precipitation,the seasonal temperature and the runoff show a good positive correlation.