基于DEM的地形起伏度最佳计算尺度的研究——以仙居县为例

Study on Optimal Scale for Calculating Relief Amplitude Based on DEM:A Case of Xianju County

在区域性研究中,地形起伏度是反映地形起伏特征的宏观因子,利用DEM数据作为基本信息源,能够快速、直观地提取地形起伏度。本文以仙居县1∶1万DEM数据作为基础数据源,利用矩形窗口的邻域分析获取多尺度地形起伏度,探讨提取适合研究区地貌分类的地形起伏度最佳统计单元,并统计不同地貌类型面积比。研究表明,仅仅依靠地形起伏度一个指标作为划分地貌形态的指标,有一定的局限性。本文加入海拔高度作为辅助因子后,更有效地划分了平原与丘陵地貌,分类结果更加准确。

In the regional studies,relief amplitude is a macroscopic factor that reflects the topographic relief,and u-sing DEMdata to extract relief can quickly and intuitively reflect topographic relief feature.In this paper,based on the 1∶10 000 DEMdata in Xianju county,the author used neighborhood analysis of rectangular analysis window to obtain multi-scale relief,and determined optimal statistical unit of suitable for the study area of geomorphologic classification, and counted the area ratio of various geomorphic type.The research shows that it just rely on relief as an indicator of geo-morphologic forms classification index have certain limitations.In this paper,after added the altitude as the auxiliary fac-tor,the plain and hilly terrain are divided more effectively,and the classification results are more accurate.