基于DEM的山区土地利用变化分析

地形因子直接影响土地利用方式并在一定程度上决定着土地利用类型。以西南地区典型山区重庆市忠县为研究区，基于DEM和遥感影像，通过遥感解译建立土地利用数据库，运用GIS技术提取高程、坡度、坡向，并与土地利用图进行叠加，分析研究区2000—2010年间基于不同地形因子的土地利用变化情况。研究结果表明:地形因子对研究区土地利用变化有着重要的影响，土地利用变化随着高程的增加、坡度的增大而减缓，阳坡大于阴坡，并主要集中在高程为300～600 m，坡度 < 25°的半阳坡地区，其中以耕地与林地之间的转化最为剧烈；在海拔为0～300 m，坡度 < 25°的长江及其支流沿岸地区有一定面积的耕地和林地转化为水域。通过对土地利用变化与各地形因子之间关系的分析，有助于实现区域土地利用结构的优化和不同地形上土地利用类型的合理布局，促进区域土地资源的可持续发展。

Analysis of Land Use Change in Mountain Area Based on DEM

Terrain factor affects land use manner directly and determines the land use type to a certain extent. Taking Zhongxian county of Chongqing a typical mountainous area in southwest as study area. Based on the DEM and remote sensing images, through the establishment of land use remote sensing database, using GIS technology, elevation, slope, aspect was extracted, and made them overlay to land use map to analyze land use change based on different terrain factors from 2000 to 2010 in the study area. The research results show that the terrain factors have the important influence on land use change in the study area, land use change decreases slowly with the increase of elevation and slope, sunny slope is greater than the shady slope, and mainly concentrated in the region that the elevation is 300~600 m, slop is less than 25° and the aspect is half-sunny slope, and the transformation between cultivated land and forest land is the most violent one. There are certain areas of cultivated land and forest land were converted to water in elevation 0~300 m, less than 25° along the Yangtze River and its tributaries. The analysis of relation between land use change and each terrain factors will have benefit to realize the optimization structure of regional land use and the rational distribution of land use types on different terrain, to promote the sustainable development of regional land resources.