Aspect in Topography to Enhance Fine-detailed Landform Element Ex-traction on High-resolution DEM

• 作者: XIE Xiao ZHOU Xiran XUE Bing XUE Yong QIN Kai LI Jingzhong YANG Jun
• 来源期刊: 中国地理科学（英文版）
• 年，卷（期）: 2021,（5）
• 页码范围: 915-930
• 页数: 16页
• 语种: 英文

摘要

The value of the high-resolution data lies in the high-precision information discovery.The fine-detailed landform element ex-traction is thus the basis of high-fidelity application of the high-resolution digital elevation models (DEMs).However,the results of landform element extraction generated by classical methods might be ungrounded on high-resolution DEMs.This paper presents our re-search on using the aspect to reinforce the applicability and robustness of the classical approaches in landform element extraction.First,according to the research of pattern recognition,we assume that aspect-enhanced landform representation is robust to rotation,scaling and affine variance.To testify the role of aspect,we respectively integrated the aspect into three classical approaches:mean curvature-based fuzzy classification,elevation-based feature descriptor,and object-based segmentation.In the experiment,based on four types of high-resolution DEMs (1 m,2 m,4 m and 8 m),we compare each classical approaches and their corresponding aspect-enhanced ap-proaches based on extracting the rims of two craters having different landforms,and the ridgelines and valleylines of a region covered by few vegetables and man-made buildings.In comparison to the results generated by curvature-based fuzzy classification,the aspect enhanced curvature-based fuzzy classification can effectively filter a number of noises outperforms the curvature-based one.Otherwise,the aspect-enhanced feature descriptor can detect more landform elements than the elevation-based feature descriptor.Moreover,the as-pect-based segmentation can detect the main structure of landform,while the boundaries segmented by classical approaches are messing and meaningless.The systematic experiments on meter-level resolution DEMs proved that the aspect in topography could effectively to improve the classical method-system,including fuzzy-based classification,feature descriptors-based detection and object-based seg-mentation.The value of aspect is significantly great to be worthy of attentions in landform representation.