1961-2015年吉林省降雨侵蚀力的时空变化特征

目的]分析吉林省1961-2015年降雨侵蚀力的时空变化趋势,为该省的农业和生态保护、水土保持等工作提供科学依据.方法]利用吉林省46个自动气象站1961-2015年逐日降雨量资料估算吉林省逐气象站的降雨侵蚀力,并采用相关系数、气候倾向率和反距离空间插值方法分析吉林省降雨侵蚀力的时空变化趋势.结果]吉林省年平均降雨侵蚀力在空间分布上从集安开始呈向西北和东北逐渐递减的变化趋势,其空间分布特征与年平均降水量的空间分布特征基本一致.时间分布上与多年平均降水量的时间分布特征具有高度一致性,在7月达到峰值.有34.8％的气象站点降雨侵蚀力呈上升趋势,中、西部大部分地区呈下降趋势,东部有1/2以上呈上升趋势,但只有长白站的下降趋势通过显著性检验.不同地区各年代平均降雨侵蚀力变化也不一致,具有波动性.不同年代各降雨侵蚀力等值线在空间分布上总体变化不大.结论]吉林省降雨侵蚀力在时空变化上与降水量一致,不同地区降雨侵蚀力变化趋势不一样,几乎没有通过显著性检验.

Temporal-spatial Variation Characteristics of Rainfall Erosivity in Jilin Province During 1961 to 2015

Objective] The temporal and spatial variation trend of rainfall erosivity in Jilin Province from 1961 to 2015 were analyzed to provide scientific bases for agricultural and ecological protection, as well as soil and water conservation.Methods] Based on the daily rainfall data from 46 meteorological stations in Jilin Province from 1961 to 2015, rainfall erosivity was estimated and the temporal and spatial distribution was analyzed with correlation coefficient, climate tendency rate and the inverse distance interpolation methods, respectively.Results] The spatial distribution of rainfall erosivity has a decreasing trend from the station of Jian to the northwest and northeast region. The spatial distribution of average annual rainfall erosivity is similar to that of average annual precipitation. The temporal distribution of yearly averaged rainfall erosivity is similar to that of multi-year average precipitation, which has a peak in July. 34.8% meteorological stations have incline rainfall erosivity. For most of the western region, there is a downward trend; while for more than half of the stations in eastern region is on the rise, among with Changbai station was significant. The changes of average rainfall erosivity of each decade in different regions are not consistent, and have fluctuation. The spatial distribution of rainfall erosivity contour in different decade differ slightly.Conclusion] Rainfall erosivity in Jilin Province is consistent with the precipitation in temporal and spatial variation, and the trend of rainfall erosivity in different regions is different, and almost dose not pass the significance test.