试论水利部土壤侵蚀分级方法的适用性

在分析水利部土壤侵蚀强度分级两种方法的基础上，以黄河流域为例分析了间接指标分级法的适用性。直接指标法以年均土壤侵蚀模数或年均土壤侵蚀厚度为指标划分侵蚀强度级别；而间接指标法以下垫面影响土壤侵蚀的自然因子为指标，判断土壤侵蚀强度。实际应用中直接获得侵蚀模数和侵蚀厚度比较困难，因此一般用间接指标法评估土壤侵蚀强度。基于前期研究建立的土壤侵蚀快速评估法，用间接因子评估了黄河流域土壤侵蚀强度，通过与遥感调查结果的比较，分析了间接指标法的适用性，为该方法的应用提供了参考依据。

Applicability of the Classification Method of Soil Erosion Intensity

Two classification methods of soil erosion intensity are set by the Ministry of Water Resources of PR China.One is direct index method which takes soil erosion modulus or annual soil erosion thickness as the classification index.The other is indirect index method which takes some earth surface factors influencing soil erosion as the classification index.In practice,the indirect method is usually adopted because of its convenience in data collection.Based on the rapid assessment method of soil erosion proposed in the authors' previous study,the soil erosion intensity is assessed for the Yellow River basin by using the indirect method.Comparing the assessment results with the investigation results,the applicability of the indirect index method is analyzed,providing reference for the application of the indirect classification method of soil erosion intensity.