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为研究云南省及5个子区域年降雨侵蚀力和各量级降雨侵蚀力的时空变化特征,基于云南120个站点近43a逐日降水资料,利用Man-Kendall趋势检验、Morlet连续复小波变换分析等方法进行系统分析。结果表明:各区域大雨侵蚀力在年降雨侵蚀力中起主导作用;年内各月降雨侵蚀力滇西北基本以大雨侵蚀力为主,其余区域干季以中雨侵蚀力为主,雨季以大雨侵蚀力为主;各量级降雨侵蚀力表现出降雨量级越大,季节性越强,集中程度越高的特征;各区域中雨侵蚀力相对变化呈减少趋势,其余量级降雨侵蚀力变化趋势以减居多;暴雨侵蚀力相对变化程度最强,大雨和中雨侵蚀力相对较缓;滇西北年降雨侵蚀力、大雨和中雨侵蚀力以9a左右时间尺度为主震荡周期,其余区域主震荡周期多为18~21a左右,暴雨侵蚀力主震荡周期在各区域存在一定差异。
In order to study the temporal and spatial variation characteristics of annual rainfall erosivity and rainfall erosivity in Yunnan Province and five sub-regions, based on the daily precipitation data of 120 sites in Yunnan Province in recent 43 years, Man-Kendall trend test and Morlet continuous complex wavelet transform analysis Systematic analysis. The results show that the heavy rainfall erosivity plays a leading role in the annual rainfall erosivity. In each month, the rainfall erosivity is mainly rain erosive force in the northwest of Yunnan Province, while in the remaining regions, The main features of the rainfall erosivity are as follows: the rainfall erosivity of each magnitude shows the features of larger rainfall season, stronger seasonality and higher concentration; the relative change of erosivity in each area shows a decreasing trend; And the erosion intensity of rainstorm was relatively slow. The rainfall erosivity, heavy rain and moderate rainfall erosivity of northwestern Yunnan were dominated by the time scale of about 9 years, and the main shocks occurred in other regions The period is mostly about 18 ~ 21a, and the main shock cycle of rainfall erosive force is different in all regions.