Terrain Skeleton Construction and Analysis in Loess Plateau of Northern Shaanxi

Abstract

A terrain skeleton determines the overall structure and characteristics of the terrain and indicates the presence of significant terrain features, such as ridges and valleys. It plays an important role in terrain representation and reconstruction, hydrological analysis of watersheds, and other scientific studies and engineering applications. Previous studies of terrain skeleton have been mostly focused on the extraction of terrain skeletons, ignoring their important effect on terrain analysis. Therefore, this work proposes a new terrain skeleton, which includes three types of terrain skeleton points and two types of terrain skeleton lines. The terrain control points are peak, saddle, and valley nodes, while the terrain skeleton lines are connection lines of peaks and saddles and connection lines of saddles and valley nodes. The terrain skeleton connects isolated terrain control points together. The data structure is designed, and three analysis indicators, namely, nearest-neighbor index, topological connectivity index and landscape shape index are selected. Results show that the three selected indicators can reflect the spatial structure of the terrain skeleton and describe the landform development to a certain extent. Different areas of the same landform, such as the two sample areas in Shenmu County, show variations.