浙江省降雨侵蚀力变化特征分析

根据浙江省83个气象站1980-2009年逐日雨量资料,采用日降雨侵蚀力模型,运用Mann-Kendall非参数检验和径向基函数插值等方法,研究了该省降雨侵蚀力变化的时空分布特征。结果表明,近30a来浙江省多年降雨侵蚀力长期变化趋势不显著,但冬季呈显著上升趋势,1和12月为上升趋势的主要贡献月份;浙江省多年平均降雨侵蚀力由西北向东南递增,月、季降雨侵蚀力变化趋势显著的集中区主要位于浙中浙北地区,但夏季降雨侵蚀力较大,上升趋势显著的集中区位于该省东南部,该地区降雨潜在侵蚀动能较大,是水土保持的重点区域。

An Analysis of Rainfall Erosivity Change in Zhejiang Province

Based on a long time series(1980-2009)daily rainfall data collected by 83meteorological stations,the rainfall erosivity in Zhejiang Province was calculated by using daily rainfall erosivity model.The temporal changes and its spatial distribution characteristics of rainfall erosivity were analyzed by using the non-parametric Mann-Kendall test and radial basis function interpolation.The results indicated that there are no significant changes in the long-term mean annual rainfall erosivity,significant increases of rainfall erosivity occurred in winter,especially in January and December.An increasing trend in mean annual rainfall erosivity was showed from the northwest to the southeast of Zhejiang Province.While the most monthly and seasonally rainfall erosivity changes mainly occurred in the northern and the central part of Zhejiang Province with the rainfall erosivity was obviously higher in summer than that in other three seasons.As the main region where the most significant rainfall erosivity changes occurs,and the region with relative high rainfall kinetic energy,southeast part of Zhejiang Province was regarded as the key area for soil and water conservation.