龙川江流域主要气象要素及径流变化趋势分析

采用Mann-Kendall非参数检验法对金沙江一级支流龙川江流域1970年-2009年逐月气温、降水及1961年-2008年径流资料进行趋势检验,并运用R/S方法分析流域的年平均气温、降水、径流时间序列的持续性,估算各项指标的Hurst指数,以定量估计未来气候及径流的变化趋势。结果表明:(1)过去几十年来,流域内降水呈上升趋势但不显著,未来降水将持续增加且元谋站降水的增长趋势持续性较强;(2)几十年来,流域气温呈显著上升趋势,未来气温将会持续过去的上升趋势;(3)几十年来,流域径流呈减少趋势,但不显著,未来继续呈下降趋势,但持续性不强。

Variation Trend Analysis of Major Climatic Variables and Runoff in the Longchuan River Basin

In this study, the long-term trends of monthly temperature and precipitation from 1970 to 2009 and annual runoff data from 1961 to 2008 in the Longchuan River Basin were analyzed using the non-parametric Mann-Kendall method. In addition, the R/S method was used to investigate the continuity of the time series data of annual temperature, precipitation, and runoff in the basin and to estimate the Hurst exponent for each index, which can be used to estimate the variation trends of temperature, precipitation, and runoff quantitatively. The results showed that (1) precipitation has an insignificant increasing trend in the basin and it will continue to increase, especially at Yuanmou station; (2) temperature has a significant increasing trend in the basin and it will continue to increase; and (3) runoff has an insignificant decreasing trend in the basin and it will continue to decrease but without strong continuity.