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In this study, a geometric-optical model (GOST model) was used to simulate the canopy gap fraction of a forest. Then, a canopy closure estimation method using the gap fraction was discussed. In this study, three typical planted forest farms (the Mengjiagang (MJG), Gaofeng (GF), and Wangyedian (WYD) forest farms) containing the most commonly planted tree species in the north and south regions of China were selected, and field measurements were executed. The results show that the gap fraction (Pvg-c) had a higher correlation with the average projected area of the tree crowns, and the relationship was an exponential function, with R2 and RMSE values of 0.5619 and 0.0723, respectively. Finally, the applicability and accuracy of this method were evaluated using line transects, and a fisheye camera measured the canopy closure. The accuracy of the canopy closure estimated by the Pvg-c was 86.69%. This research can provide a reference for canopy closure estimation using a geometric-optical model.<\/jats:p>","DOI":"10.3390\/rs14091983","type":"journal-article","created":{"date-parts":[[2022,4,21]],"date-time":"2022-04-21T03:46:11Z","timestamp":1650512771000},"page":"1983","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Stand Canopy Closure Estimation in Planted Forests Using a Geometric-Optical Model Based on Remote Sensing"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6441-6836","authenticated-orcid":false,"given":"Xiguang","family":"Yang","sequence":"first","affiliation":[{"name":"School of Forestry, Northeast Forestry University, Harbin 150040, China"},{"name":"Key Laboratory of Sustainable Forest Ecosystem Management\u2014Ministry of Education, Northeast Forestry University, Harbin 150040, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ping","family":"He","sequence":"additional","affiliation":[{"name":"School of Forestry, Northeast Forestry University, Harbin 150040, China"},{"name":"Key Laboratory of Sustainable Forest Ecosystem Management\u2014Ministry of Education, Northeast Forestry University, Harbin 150040, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4305-3271","authenticated-orcid":false,"given":"Ying","family":"Yu","sequence":"additional","affiliation":[{"name":"School of Forestry, Northeast Forestry University, Harbin 150040, China"},{"name":"Key Laboratory of Sustainable Forest Ecosystem Management\u2014Ministry of Education, Northeast Forestry University, Harbin 150040, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Wenyi","family":"Fan","sequence":"additional","affiliation":[{"name":"School of Forestry, Northeast Forestry University, Harbin 150040, China"},{"name":"Key Laboratory of Sustainable Forest Ecosystem Management\u2014Ministry of Education, Northeast Forestry University, Harbin 150040, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,4,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"S1","DOI":"10.1186\/1179-5395-44-S1-S1","article-title":"Third International Congress on Planted Forests: Planted Forests on the Globe-Renewable Resources for the Future","volume":"44","author":"Payn","year":"2014","journal-title":"N. 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