淮河流域降雨-侵蚀背景及时空演变特征

Potential Erosive Power of Rainfall and Spatiotemporal Variation Characteristics in the Huaihe River Basin

当前全球气候正经历以变暖为主要特征的显著变化,为土壤侵蚀及水土流失的防治提出新的挑战。研究探索气候变化特别是降雨变化特征、时空演变及对侵蚀的潜在影响,是深刻认识气候变化与土壤侵蚀之间关联,减少未来水土流失防治不确定性的前提和基础。以降雨侵蚀力为指标,对淮河流域降雨—侵蚀背景及时空演变特征进行了计算分析。结果表明:1951—2008年间流域多年降雨的潜在侵蚀能力为5 269.12 MJ/(mm.hm2.h),峰值位于南部的大别山区。时间演变上,全流域多年降雨—侵蚀背景未呈现显著增减趋势。空间变化上,周口、大别山区及蚌埠附近三个地区潜在侵蚀背景的上升趋势最为显著,北部鲁中南低山丘陵沿脉区域也呈现一定上升趋势,以上区域应优先加强侵蚀防治对未来降雨变化的适应研究。

The current global climate is experiencing a significant change with an average increase in the earth temperature as the main feature,which presents new challenge on soil erosion control.Exploring the potential influence and spatiotemporal variation from climate change especially precipitation change is foundation to reveal the relationship between climate change and soil erosion for reducing the uncertainty in future practice.By using rainfall erosivity as an indicator,potential erosivie power and spatiotemporal variation characteristics were discussed on the Huaihe River basin.Results showed that the average annual rainfall erosive power was 5 269.12 MJ/（mm·hm2·h） during 1951—2008 and the peak centre was located in the south of Dabie Mountain Area.No significant statistical trend was found on temporal erosivity change through time series test method.Spatially,there were three distinct erosivity-increasing centers including Zhoukou City,Dabieshan Mountain Area and Bengbu City.In addition,the rainfall erosive power in middle souther of Shandong hilly areas in the north basin also showed an obvious increasing state.Strengthening adaptation research on water erosion control in future precipitation change should be considered prior to those above regions.