【摘要】 数字高程模型(DEM)的应用对全省各县开展的二次土地调查具有指导性意义。以榆中县为实验区,通过应用DEM进行耕地坡度分级量算并对其适宜性进行分析,通过对不同坡度计算模型的对比分析,对耕地坡度与地形坡度差异的分析,对用不同比例尺(不同分辨率)DEM量算耕地坡度的成果对比分析,对不同坡度值确定方法所表达的坡度值的准确性对比分析,得出以下结论:在黄土高原沟壑区可采用地形坡度代替耕地坡度,并且选择20m等高距DEM进行耕地坡度量算是最优选择;采用坡度图与数据库叠加进行耕地坡度等级量算的耕地坡度派生方法中,使用概率坡度模型较为可行。更多还原

【Abstract】 The application of Digital Elevation Model(DEM)had instructional significance in the second terrain investigation in Gansu Province.This work took Yuzhong County as study area.An algorithm using DEM to classify agrarian slope was employed in this study.The feasibility of this algorithm was analyzed soon.The comparisons in three aspects including the difference of the slope calculations for farmland,the difference between agrarian slope and topographical slope,and the accuracy of the results calculated with different models or using the DEM datasets in different scales(or spatial resolution)were operated in this study.From this paper,two points have been observed.Firstly,topographical slope could instead of agrarian slope in gullied regions in the Loess Plateau;additionally,the DEM with the interval of 20 meters is the best choice for slope calculations for farmland.Secondly,to overlay probabilistic slope model with database was more feasible in the slope calculations for farmland.更多还原