用Guelph法研究南方低丘缓坡地不同坡位土壤渗透性

利用 Guelph入渗仪研究了我国南方低丘缓坡地不同坡位的土壤渗透性。对第四纪红色黏土和红砂岩发育土壤的研究结果表明 ,坡地上不同坡位土壤的渗透性差别显著 ,0— 5 cm表层土壤的饱和入渗率Kfs值总是下坡最大 ;草地上植被覆盖度越高 ,表层土壤的 Kf s值也越大 ;而旱耕地上表层土壤 Kfs值与坡位之间的关系则表现为 :下坡 >上坡 >中坡

Soils Permeability on Different Position of Upland Measured by Guelph Method in Hilly Area of South China

The both special data structures, vector and raster, are used in surveying the regional soil erosion survey and mapping soil erosion intensity atlas based on the RS GIS (Remote Sensing and Geographic Information System). The methods and techniques were discussed, including how carve up polygons, how to capture the values of factors of impressing soil erosion, and how to differentiate erosion intensity. According to the analysis results based on the two special data structures, the two methods can both be used to estimate the soil erosion intensity, but each method has its respective characteristic. The method based on raster can reflect more of the erosion differentiation between the micro regions, meanwhile the method based on vector can do more of the distribution of various erosion intensity grade. From the dynamic monitoring and trend forecasting, it is convenient and more rapid for raster to capture the value of erosion factors, to analyze dynamic pattern and to predict the development.