Study On Soil Erosion Based On Grid Data In Karst Mountainous Region

This paper studied the method of soil erosion in karst mountainous region based on the grid data and RUSLE model. In the course, RS (remote sensing) and GIS (geographic information system) were used. We estimated the status in quo and potential danger of soil erosion combined with some work in Guizhou province. The followed is the central content and harvest.1. On the base of the study on advantage and disadvantage of internal and external soil erosion model, we established the model of soil erosion in karst mountainous region used the RUSLE as the frame.2. The isolines of rainfall erosivity factor (R) were protracted and the sensitivity of soil erosion was classified in the study area by the technology of GIS.3. One method of calculation of soil erodibility factor (K) was created through the triangle table of soil quality in America and the table of soil erodibility factor (K) in USLE to the characteristic of old soil data in China.4. DEM of 1:250000 was created in study area and on the base, the database of slop steepness, slop length and undulant degree of topographty were built.5. The crop and management factor (Q and the conservation practices factors (P) were estimated in the study area through the combination of vegetation index and landuse data being derived from TM image in 2000.6. The quantitative monitoring of regional soil erosion was realized and the database of soil erosion modulus in study area through the combination of microcosmic study and macroscopical evaluation based on the grid data.In conclusion, the techniques and methods monitoring regional soil erosion based on RS and GIS, including the model, unit of assessment, extraction of parameter value, judgment of erosion intensity and so on, are proposed in the paper. It is also academic and practiced significance for the researching, monitoring and management of soil erosion in karst mountainous area.