在前期研究的基础上,将基于最小图斑的土壤侵蚀快速评估方法应用到黄河流域土壤侵蚀的评估中,建立了土壤侵蚀特征指标(EI)与土壤侵蚀强度E之间的判别分析关系,并根据判别函数判断EI的归属类别,从而获得每个图斑的土壤侵蚀强度.经敏感性分析,说明评估结果是稳定可靠的.应用表明,土壤侵蚀特征指标能够较好地表征流域土壤侵蚀强度;土壤侵蚀快速评估方法在实际应用中具有明显优势,不仅对输入数据和参数要求相对较低,而且能够提高模型的评估效率.
By use of the rapid assessment approach of soil erosion based on minimum polygons, a case study is conducted in the Yellow River basin where serious erosion is occurring. The soil erosion characteristic index E1 is calculated and the discriminants between E1 and soil erosion intensity (E) are constructed. Then, E in each polygon is assessed by the discriminants. Sensitivity analysis proves the results with good stability. Comparisons are given between the predicted and observed results, and zoning maps are worked out for the Yellow River basin at the end of the 1980s,which indicates the parameter E1 could reasonably reflect the characteristics of the soil erosion intensity. The application proves that the assessment method could effectively give reasonable results with low requirements for input data and parameters.