GIS支持下的土壤侵蚀潜在危险度分级方法研究及应用

根据土壤侵蚀特点,在ARCGIS8.3地理信息系统(GIS)支持下,有效地实现了区域土壤侵蚀强度分级并在此基础上进行了区域土壤侵蚀潜在危险的分级及其空间分析。首先,采用区域土壤侵蚀定量模型估算土壤侵蚀量,再用土壤年均侵蚀量、土层厚度和土壤容重得到土壤抗蚀年限图,按水利部标准将土壤侵蚀潜在危险度分为5级。最后,为了表明该区域土壤侵蚀潜在危险度的大小,还提出了土壤侵蚀潜在危险指数(SEPDI)。以三峡库区的丰都县城为例进行了研究,并且分析了其空间分布特点。

GIS Based Gradation Method and Its Use of Soil Erosion Risk

Soil erosion risk was graded using results from an analysis of soil erosion characteristics based on Geographical Information System ARCGIS. The process of grading the potential danger of soil erosion and its spatial distribution is straightforward in ARCGIS. Firstly, soil erosion modulus is estimated using a water erosion model, and maps of soil density and soil horizon thickness are derived from detailed soil survey data. Then, the temporal character of soil loss is calculated using soil erosion modulus, soil thickness and soil density. Next, in line with Ministry of Water Resources' classification standards, the potential danger of soil erosion is divided into five grades and an index of soil erosion potential danger(SEPDI) is established. The SEPDI has been tested in a case study in Fengdu County in the Three Gorges area, with ARCGIS used to assess erosion potential distribution characteristics.