岷江流域径流演变及其对气候变化的响应

Runoff Variation in Minjiang River Basin and its Response to Climate Change

基于岷江流域近52年（1961-2012）的径流与气象数据,采用线性回归、非参数检验（Mann-Kendall法）、Morlet小波变换、Pearson相关分析等方法,对岷江流域径流、气温、降水等主要水文气象要素进行分析.结果显示：（1）近52年来岷江流域年平均气温总体呈明显增长趋势,年均降水量呈显著下降趋势,年均气温以0.15℃/10 a的速率增加,年均降水量以20.18 mm/10 a的速率减少,区域气候的暖干化趋势明显.（2）岷江流域多年径流量呈显著减少趋势,减少速率为20.38×10^8m^3/10 a,流域径流量在1968年左右出现减少突变,20世纪70年代早期开始径流量增加,1993年左右又发生一次减少突变,径流显著减少.（3）通过对年径流量序列进行Morlet小波转换分析发现,岷江流域径流量主要存在6-9 a的年际周期、17 a和28 a的年代际周期,径流量总体特征是向干枯化趋势发展.（4）通过年径流量与气象因素的相关分析发现,区域降水量是影响岷江流域径流减少的主导因子,在该流域降水量减小的背景下,气温升高进一步加剧了流域径流量的减小;流域径流对暖干气候的响应表现为径流量减少.

Based on the runoff and meteorological data of Minjiang River Basin in recent 52 years（1961-2012）, the run-off, temperature and precipitation status were analyzed by using methods of linear regression, Mann-Kendall non-para-metric statistical tests, Morlet wavelet and Pearson Correlation Coefficient. Results showed as follows：（1） Temperaturepresented an increasing trend over the last 52 years in Minjiang River Basin, the temperature increase rate being 0.15°C/10 a, precipitation presented a decreasing trend, the precipitation decrease rate being 20.18 mm/10 a, and climatic warm-drying trend was apparent.（2） Runoff presented a significant decreasing trend in recent 52 years in Minjiang River basin,the runoff decrease rate was 20.38×10^8m^3/10 a, the runoff witnessed reduce mutation around 1968, and increased in early70＇s, while around 1993 the runoff reduce mutation occurred again, with the runoff decreasing significantly since 1990＇s.（3） The annual runoff was analyzed by Morlet wavelet transform method and found that the runoff has a 6-9 years periodicoscillation, a 17 years and 28 decadal periodic oscillations, with an obvious drying trend in Minjiang River Basin.（4） Thecorrelation between annual runoff and meteorological factors was analyzed by using method of Pearson correlation coeffi-cient, finding that precipitation was the main factor which led to the runoff reduction in Minjiang River basin, the risingtemperatures aggravated the reduction of runoff, and the response of the runoff to warm-drying climate was the perfor-mance of runoff reduction.