{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T02:52:24Z","timestamp":1760151144942,"version":"build-2065373602"},"reference-count":60,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2022,2,15]],"date-time":"2022-02-15T00:00:00Z","timestamp":1644883200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Open Project Program of State Key Laboratory of Luminescence and Applications","award":["SKLA-2021-07"],"award-info":[{"award-number":["SKLA-2021-07"]}]},{"DOI":"10.13039\/501100001809","name":"Natural Science Foundation of China","doi-asserted-by":"publisher","award":["41571398","41701450"],"award-info":[{"award-number":["41571398","41701450"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJGI"],"abstract":"<jats:p>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.<\/jats:p>","DOI":"10.3390\/ijgi11020136","type":"journal-article","created":{"date-parts":[[2022,2,15]],"date-time":"2022-02-15T22:43:22Z","timestamp":1644965002000},"page":"136","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Terrain Skeleton Construction and Analysis in Loess Plateau of Northern Shaanxi"],"prefix":"10.3390","volume":"11","author":[{"given":"Min","family":"Li","sequence":"first","affiliation":[{"name":"School of Geographic Information and Tourism, Chuzhou University, Chuzhou 239099, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ting","family":"Wu","sequence":"additional","affiliation":[{"name":"Panda Wisdom Water Co., Ltd., Shanghai 201703, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Weitao","family":"Li","sequence":"additional","affiliation":[{"name":"School of Geographic Information and Tourism, Chuzhou University, Chuzhou 239099, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chun","family":"Wang","sequence":"additional","affiliation":[{"name":"School of Geographic Information and Tourism, Chuzhou University, Chuzhou 239099, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7424-644X","authenticated-orcid":false,"given":"Wen","family":"Dai","sequence":"additional","affiliation":[{"name":"School of Remote Sensing & Geomatics Engineering, Nanjing University of Information Science & Technology, Nanjing 210044, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xu","family":"Su","sequence":"additional","affiliation":[{"name":"School of Earth Science and Engineering, Hebei University of Engineering, Handan 056009, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yuanyuan","family":"Zhao","sequence":"additional","affiliation":[{"name":"School of Earth Science and Engineering, Hebei University of Engineering, Handan 056009, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,2,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"68","DOI":"10.1007\/BF02833889","article-title":"The derivation of skeleton lines for terrain features","volume":"5","author":"Peizhi","year":"2002","journal-title":"Geo-Spat. 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