中文摘要：

土壤侵蚀演化风险是在一定的空间范围内土壤侵蚀风险的时间变化关系,是发生土壤侵蚀可能性的动态演变过程,其对于评价不同时空尺度水土保持措施的合理性及其效益意义重大。以位于黄土高原中部的泾河流域为例,基于1986年、1995年和2000年的三期土地利用类型空间数据,利用GIS技术和信息熵理论,结合美国通用土壤流失方程（Universal Soil Loss Equation,USLE）,提出土壤侵蚀风险演化因子及其计算公式,分析泾河流域19862000年的土壤侵蚀演化风险。结果表明：泾河流域土壤侵蚀演化风险与流域降雨侵蚀力的空间分布有密切联系,土壤侵蚀演化风险呈现先增加而后下降的趋势,流域20多年的水土保持工作总体来说较为有效。该研究可为区域土壤侵蚀演化风险分析提供新的思路。

英文摘要：

Evolution risk of soil erosion is defined as a time changing relationship of soil erosion risk within a certain spatial extent,which is a dynamic evolution process of soil erosion possibility.It is important to evaluate the rationality and benefit of soil and water conservation measures with the notion of evolution risk of soil erosion on different temporal and spatial scales.The study took the Jinghe River Basin located in the center of the Chinese Loess Plateau as an example.Three space data of land use in 1986,1995 and 2000 were considered.A notion of evolution risk factor and its calculation formula were presented to analyze the evolution risks of soil erosion（ERSE） over the 1986-2000 period in the Jinghe River Basin based on GIS technique,information theory and the Universal Soil Loss Equation.Results demonstrate that there is close relationship between the ERSR and the spatial distribution of rainfall erosivity factor.The ERSE shows an increasing trend firstly and then a decreasing one.The soil and water conservation measures for more than 20 years are effective in general.This study could offer a new tool to analyze regional ERSE.