1957-2017年泾河流域降雨量及降雨侵蚀力时空变化分析

泾河流域受土壤侵蚀的影响,水土流失较为严重,为对流域水土流失风险评估和防治等提供参考依据,根据1957-2017年泾河流域5个气象站点的日降水资料,运用ArcGIS空间插值、小波分析、R/S分析等方法,分析了该时段降雨量及降雨侵蚀力时空变化规律。结果表明:泾河流域及各气象站点的降雨量与降雨侵蚀力均呈显著正相关关系;泾河流域降雨量与降雨侵蚀力年内分布不均,主要集中在夏季,分别占全年的67.80%和52.86%;泾河流域年均降雨量和降雨侵蚀力分别为496.83 mm和1 481.24 (MJ·mm)/(hm~2·h),年际总体呈波动上升趋势且未来降雨侵蚀力将延续增加趋势,两者均在1996和2009年出现突变点且第一主周期分别为27和17 a;泾河流域降雨量和降雨侵蚀力在空间上均呈从西北到东南递增的趋势。

Spatio temporal variations of rainfall and rainfall erosivity in Jinghe River Basin from 1957 to 2017

The Jinghe River Basin is seriously affected by soil erosion, resulting in severe water and soil loss in the area. In order to provide a reference for risk assessment and prevention of soil erosion, we analyzed the spatio temporal variations of rainfall and rainfall erosivity in Jinghe River Basin from 1957 to 2017 using ArcGIS spatial interpolation, wavelet analysis and R/S analysis, based on the daily precipitation data of five stations in the basin. The results showed that there was a significant positive correlation between the rainfall and rainfall erosivity in each of the five stations in Jinghe River Basin. The annual distribution of rainfall and rainfall erosivity in the basin was uneven, mainly in summer, accounting for 67.80% and 52.86% of the whole year respectively; The average annual rainfall and rainfall erosivity of Jinghe River Basin were 496.83 mm and 1 481.24 (MJ · mm) / (hm² · h) respectively, both of which showed a fluctuated upward trend, with the prospect of continuous increase of the rainfall erosivity in the future. Both of the rainfall and rainfall erosivity experienced abrupt changes in 1996 and 2009, and their first main cycle was 27 a and 17 a respectively. Spatially, the rainfall and rainfall erosivity of the basin increased from northwest to southeast.