基于GIS和USLE模型的土壤侵蚀定量研究—以伊通满族自治县为例

Based on the Quantitative Study of GIS and USLE Model of Soil Erosion—Taking Yitong Manchu Autonomous County as an Example

利用GIS技术,基于美国通用水土流失方程(USLE)和ArcGIS软件,对吉林省伊通满族自治县进行水土流失定量研究,得出该地区土壤侵蚀状况与空间分布特征,并与坡度、地貌、植被盖度、土地利用进行叠加,分析四个因子对土壤侵蚀的影响情况。研究表明:1) 研究区占地面积2533.11 km2,2016年侵蚀面积为991.44 km2,占本县土地总面积的39.14%,以中度侵蚀为主,占侵蚀总面积的49.91%,与2011年水利普查结果相比,总侵蚀面积减少了41.03 km2。2) 土地利用类型中旱地及裸岩或裸地的土壤侵蚀强度及面积相对较大,水域及林草地侵蚀相对较少。3) 在不同的坡度条件下,坡度越低侵蚀越微弱,坡度越高侵蚀越剧烈。4) 随着高程的增加土壤侵蚀强度呈现先增加然后减少的趋势,高程位于350 m以下为侵蚀发生的主要区域。5) 植被盖度越高侵蚀越弱,植被盖度越低侵蚀越强。

Using GIS technology, based on universal soil loss equation (USLE) and ArcGIS software, we did some quantitative researches about the soil erosion in Yitong Manchu Autonomous County of Jilin Province, and concluded that soil erosion and spatial distribution in the area, with slope, geomorphology, vegetation, land use overlay, and analyzed four factors on the effects of soil erosion. Studies have shown that: 1) The study area covers an area of 2533.11 km2, and the erosion area in 2016 was 991.44 km2, accounting for the county’s total land area of 39.14%, dominated by mo- derate erosion, accounting for total eroded area of 49.91%, compared with the 2011 water resources survey results, and total area of soil erosion reduced 41.03 km2. 2) The soil erosion intensity and area of dry land and bare rock or bare land are relatively large in the land use type, and the water area and forest grassland erosion are relatively few. 3) In different slope conditions, the lower the slope, the weaker the erosion;the higher the slope, the more intense the erosion being weaker. 4) With the increase of the height, the soil erosion intensity increased first and then decreased, and the elevation was below 350 m, which was the main area of erosion. 5) The higher the vegetation coverage, the weaker the erosion;the lower the vegetation coverage, the stronger the erosion.