黄土地貌区水力侵蚀敏感性分析:以山西省五寨县为例

Soil Erosion Sensitivity Analysis of Yellow Landform Areas:Taking Wuzhai County,Shanxi Province as an Example

在自然与人为因素的干扰下,黄土高原地区常年遭受较为严重的水力侵蚀。为了减缓水力侵蚀进程并避免对人类生命财产的损害,对其进行敏感性分析是具有重要意义的。从CSLE模型出发,以地貌单元作为评价单元,对降水侵蚀力因子、土壤可蚀性因子、坡长坡度因子、生物/耕作措施因子以及工程措施因子分别进行正向化处理与熵值法确权叠加后建立了一个水力侵蚀敏感性评价模型,借助面积-高程积分对该模型进行评价后,利用该模型对研究区进行水力侵蚀敏感性分析。结果表明:在区域尺度下,文中提出的水力侵蚀敏感性评价模型的评价因子为0.61,相对优于作为对比验证的CSLE模型,因此可以利用该模型对研究区进行水力侵蚀敏感性评价;水力侵蚀敏感性值在不同地貌单元之间表现为:大起伏山地>洪积平原>黄土塬>黄土梁峁>中起伏山地>冲积洪积平原;为了避免对人类生命财产造成损害,北部冲积洪积平原与中起伏山地相交地带、南部大起伏山地的清涟河流域应重点进行治理。该文提出的方法有效解决了黄土地貌区的水力侵蚀敏感性分析问题。

Under the interference of natural and human factors,the Loess Plateau area suffers from more serious hydraulic erosion all year round.In order to slow down the process of hydraulic erosion and avoid damage to human life and property,it is of great signi-ficance to conduct sensitivity analysis.A hydraulic erosion sensitivity evaluation model was established from the CSLE model,using the geomorphological unit as the evaluation unit,and the factors of precipitation erosion force,soil erodibility,slope length and slope gradient,biological/cultivation measures and engineering measures were superimposed with the entropy value method to determine the weights respectively,and then the model was evaluated with the aid of area-elevation integral.The model was then used to analyze the sensitivity of hydraulic erosion in the study area.The results show as follows.The evaluation factor of the hydraulic erosion sensitivity evaluation model proposed in the paper is 0.61 at the regional scale,which is relatively better than the CSLE model used as a comparative validation,so the model can be used to evaluate the hydraulic erosion sensitivity of the study area.The hydraulic erosion sensitivity values among different geomorphological units are as follows:large rolling hills floodplain loess plateau loess mount middle.In order to avoid damage to human life and property,the Qinglian River basin in the intersection of alluvial floodplain and mid-undulating mountains in the north and large undulating mountains in the south should be treated as a priority.The method proposed in this paper effectively solves the problem of hydraulic erosion sensitivity analysis in loess landform areas.