数字高程模型中插值算法对坡度和坡向的影响——以历山山区为例

The Influence of Interpolation Algorithm in the Digital Elevation Model on Slope and Aspect——Take Mountain Li as an Example

数字高程模型(Digital Elevation Model,简称DEM)是地表形态的数字化表达,其他地形因子如坡度,坡向等可在DEM的基础上提取.文章以山西省运城历山山区为研究区域,数据源取自样区的1∶5万的航拍地形图,利用ArcGIS软件,对比四种插值算法,反距离权重插值,样条函数插值,克里金插值和TIN(不规则三角网)插值算法所生成的DEM在提取坡度、坡向上的差异.研究结果:对于不同的插值算法,所提取的坡度在第1~10级(0°~30°)之间差异较大,所提取的坡向差异主要在正北方向,而且TIN算法产生的平地面积大于其余3种算法.

Digital Elevation Model （DEM for short） is a Digital expression of the earth＇s surface, other Terrain characteristic such as slope and aspect are derived from DEM. This study area is Mountainous Li, which is located in Yun Cheng. The date is from the plots of 1：50 000 aerial topographic maps. Using ArcGIS to compare the different between slope and aspect extrac- ted from DEM generating from four kinds of interpolation algorithm the inverse distance weighted interpolation, spline function Interpolation, kriging interpolation and TIN （Triangula- ted Irregular Network） interpolation algorithm. The found, for different interpolation algorithm, the extracted slope in 0°-30° has the major difference,while the major difference is mainly in the north direction of the aspect, and TIN algorithms produce flat area greater than the other three algorithms.