基于遥感与GIS的土壤侵蚀强度快速估测方法

针对土壤侵蚀问题,提出了一种基于遥感数据、气象数据、土壤数据的区域土壤侵蚀快速估测方法。首先,通过对土壤侵蚀问题形成原因和影响因素的分析,确定土壤侵蚀敏感性因子;其次,利用遥感(RS)、GIS技术提取土壤侵蚀敏感性因子信息;然后,在GIS系统支持下,运用主成分分析方法,进行土壤侵蚀强度分级;以北京密云水库周边区域为例,进行了土壤侵蚀估测方法的应用,并对该区域的土壤侵蚀空间特征进行分析。研究结果表明:(1)区域土壤侵蚀快速估测方法与实际情况有较好的一致性;(2)密云水库周边地区土壤侵蚀以微度和轻度侵蚀为主,所占面积比例为67.51%,中度以上侵蚀仅占面积的1.46%;(3)土壤侵蚀受坡度、地貌影响明显,中度侵蚀主要发生在低山、丘陵区以耕地为主的土地利用上以及坡度在大于25°的阳坡地带。

A method for fast estimating soil erosion intensity based on RS and GIS

Soil erosion is one of the most serious problems of eco-environment. In this paper, the main study focus on the methods of dynamically estimating soil erosion in large area based on RS and GIS. Firstly, the classification factors of soil erosion were selected by analyzing the background of soil erosion; secondly, various physical parameters of the equation were derived by processing remote sensing data and other investigation information. Thirdly, soil erosion intensity map was obtained by using the method of principal component analysis based on GIS. Finally, the spatial features of soil erosion in the region around Miyun Reservoir were analyzed with this method. The result shows that, (1) The method of soil estimation will provide quick, quantitative and scientific data for strategies of soil erosion; (2) The soil erosion in this study region is mainly in the slight intensity and low intensity, and the two erosion intensities occupies 67.51% of the total area, while the erosion of high intensity and over-high intensity are very limited, with an area percentage of less than 1.46%; (3) Spatial analysis indicates that landscape and slope contribute a large fraction of the total estimated soil erosion, and middle erosion is mainly on the low hill, where farmland is the predominant land use type or slope is above 25 degree.