南北盘江流域降水的时空变化分析

基于南北盘江流域1958～2010年的20个气象台站长期观测的降水数据,采用R/S分析法、五点二次平滑法和Mann-Kendall非参数检验法,对区域降水时空特征进行变化趋势分析以及突变检验,结果表明：（1）1953年来南北盘江流域年降雨量以25.97 mm/10a的速率呈现显著下降趋势,雨季和旱季的变化趋势明显不同,湿季降雨量减少对流域降雨量的减少有决定性影响,流域未来的降雨量仍将保持减少趋势;（2）2002年流域降雨量发生显著突变,此后几年里降雨量年际变化幅度增加;（3）1953年来年降雨量在流域内呈现出自东北向西南减少的格局,降雨量减少速率以北部和中部为最大。

ANALYSIS OF SPATIAL-TEMPORAL VARIATION OF PRECIPITATION IN THE NANPAN-BEIPAN RIVER BASIN

Based on precipitation data from the meteorological stations in Nanpan-Beipan River Basin in 1958 - 2010, the change trend and abrupt change test were analyzed by means of five-point quadratic smoothing, R/S a- nalysis method and Mann Kendall method. The following preliminary conclusions were obtained. （ 1 ） There was an obvious decrease in annual precipitation with a drop rate of 25.97 mm/10a in the region from 1958 to 2010. A descent of the rainfall in the rainy season played a dominant role in the annual precipitation reduction. Meanwhile, R/S analysis method showed that precipitation in the region had evident Hurst phenomena, and it showed that precipitation maintained decreasing trend in future. （2） Abrupt change test of annual precipitation was carried out by means of Mann Kendall method and the result indicated that the abrupt change of precipitation occurred in 2002. （3） The spatial pattern and temporal change of precipitation in the region during 1958 -2010 were ana- lyzed by using spatial interpolation method and Mann Kendall trend test with the support~of GIS, it suggested that precipitation presented clear regional spatial difference in the analyzed period, the rainfall reduced from northeast to southwest in the study area, and the north and middle part of the region had the quickest decrease in precipitation.