基于DEM的四川省坡度图制作

Mapping the Land Slope and the Land Slope Grade of the Sichuan Province Based on the DEM

第一次土地调查耕地坡度级由于采用传统方法进行量算,导致耕地系数、耕地净面积精度不高。为克服其不足,在四川省第二次土地调查中,以ArcGIS为平台,在对四川省DEM数据进行预处理的基础上,综合分析四川地形地貌特点,通过试验区验证来确定坡度计算模型进而开发坡度计算软件,制作完成按行政区划分幅(省、市、县)和按地形图分幅(1:10万、1:5万)的坡度图和坡度级图。通过对成果进行的大量验证工作(包括地形图验证和野外实地核查)表明成果中坡度级图斑和耕地图斑坡度级准确率高,数据可靠,并在四川省第二次土地调查耕地田坎样方布设以及数据库建设中全面应用。

The first land survey of china,based on the traditional survey methods,results in the inaccuracy of land coefficient and land area.In order to overcome the above error,the Sichuan Province land slope mapping of the Second land investigation,beginning in 2009,accomplished the land slope map and the land slope grade map.The work analyzed the topography and geomorphology of the Sichuan Province based on the DEM data of the Sichuan Province.The application of the land slope map and the land slope grade map in the database construction of the Second land survey of the Sichuan Province shows that the data possess relatively high accuracy and reliability.