{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,10]],"date-time":"2026-07-10T03:10:17Z","timestamp":1783653017032,"version":"3.55.0"},"reference-count":43,"publisher":"MDPI AG","issue":"21","license":[{"start":{"date-parts":[[2024,10,31]],"date-time":"2024-10-31T00:00:00Z","timestamp":1730332800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Deanship of Scientific Research at King Khalid","award":["RGP.2\/279\/45"],"award-info":[{"award-number":["RGP.2\/279\/45"]}]},{"name":"Deanship of Scientific Research at King Khalid","award":["2330169"],"award-info":[{"award-number":["2330169"]}]},{"name":"Deanship of Scientific Research at King Khalid","award":["JPMJSC23A1"],"award-info":[{"award-number":["JPMJSC23A1"]}]},{"name":"Deanship of Scientific Research at King Khalid","award":["PI#116, #ER2GCF103"],"award-info":[{"award-number":["PI#116, #ER2GCF103"]}]},{"name":"Sumitomo Foundation","award":["RGP.2\/279\/45"],"award-info":[{"award-number":["RGP.2\/279\/45"]}]},{"name":"Sumitomo Foundation","award":["2330169"],"award-info":[{"award-number":["2330169"]}]},{"name":"Sumitomo Foundation","award":["JPMJSC23A1"],"award-info":[{"award-number":["JPMJSC23A1"]}]},{"name":"Sumitomo Foundation","award":["PI#116, #ER2GCF103"],"award-info":[{"award-number":["PI#116, #ER2GCF103"]}]},{"name":"JST SICORP","award":["RGP.2\/279\/45"],"award-info":[{"award-number":["RGP.2\/279\/45"]}]},{"name":"JST SICORP","award":["2330169"],"award-info":[{"award-number":["2330169"]}]},{"name":"JST SICORP","award":["JPMJSC23A1"],"award-info":[{"award-number":["JPMJSC23A1"]}]},{"name":"JST SICORP","award":["PI#116, #ER2GCF103"],"award-info":[{"award-number":["PI#116, #ER2GCF103"]}]},{"name":"Japan Aerospace Exploration Agency (JAXA)","award":["RGP.2\/279\/45"],"award-info":[{"award-number":["RGP.2\/279\/45"]}]},{"name":"Japan Aerospace Exploration Agency (JAXA)","award":["2330169"],"award-info":[{"award-number":["2330169"]}]},{"name":"Japan Aerospace Exploration Agency (JAXA)","award":["JPMJSC23A1"],"award-info":[{"award-number":["JPMJSC23A1"]}]},{"name":"Japan Aerospace Exploration Agency (JAXA)","award":["PI#116, #ER2GCF103"],"award-info":[{"award-number":["PI#116, #ER2GCF103"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Effective forest management necessitates spatially explicit information about tree species composition. This information supports the safeguarding of native species, sustainable timber harvesting practices, precise mapping of wildlife habitats, and identification of invasive species. Tree species identification and geo-location by machine learning classification of UAV aerial imagery offer an alternative to tedious ground surveys. However, the timing (season) of the aerial surveys, input variables considered for classification, and the model type affect the classification accuracy. This work evaluates how the seasons and input variables considered in the species classification model affect the accuracy of species classification in a temperate broadleaf and mixed forest. Among the considered models, a Random Forest (RF) classifier demonstrated the highest performance, attaining an overall accuracy of 83.98% and a kappa coefficient of 0.80. Simultaneously using input data from summer, winter, autumn, and spring seasons improved tree species classification accuracy by 14\u201318% from classifications made using only single-season input data. Models that included vegetation indices, image texture, and elevation data obtained the highest accuracy. These results strengthen the case for using multi-seasonal data for species classification in temperate broadleaf and mixed forests since seasonal differences in the characteristics of species (e.g., leaf color, canopy structure) improve the ability to discern species.<\/jats:p>","DOI":"10.3390\/rs16214060","type":"journal-article","created":{"date-parts":[[2024,10,31]],"date-time":"2024-10-31T09:57:36Z","timestamp":1730368656000},"page":"4060","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Tree Species Classification by Multi-Season Collected UAV Imagery in a Mixed Cool-Temperate Mountain Forest"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3653-5771","authenticated-orcid":false,"given":"Ram","family":"Avtar","sequence":"first","affiliation":[{"name":"Graduate School of Environmental Science, Hokkaido University, Sapporo 060-0810, Japan"},{"name":"Faculty of Environmental Earth Science, Hokkaido University, Sapporo 060-0810, Japan"},{"name":"Department of Civil Engineering, Chennai Institute of Technology, Chennai 600069, Tamilnadu, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xinyu","family":"Chen","sequence":"additional","affiliation":[{"name":"Graduate School of Environmental Science, Hokkaido University, Sapporo 060-0810, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jinjin","family":"Fu","sequence":"additional","affiliation":[{"name":"Graduate School of Environmental Science, Hokkaido University, Sapporo 060-0810, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6991-1855","authenticated-orcid":false,"given":"Saleh","family":"Alsulamy","sequence":"additional","affiliation":[{"name":"Department of Architecture, College of Architecture & Planning, King Khalid University, Abha 61421, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hitesh","family":"Supe","sequence":"additional","affiliation":[{"name":"Graduate School of Environmental Science, Hokkaido University, Sapporo 060-0810, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yunus Ali","family":"Pulpadan","sequence":"additional","affiliation":[{"name":"Department of Earth and Environmental Sciences, Indian Institute of Science Education and Research Mohali, Punjab 140-306, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9272-5775","authenticated-orcid":false,"given":"Albertus Stephanus","family":"Louw","sequence":"additional","affiliation":[{"name":"Graduate School of Environmental Science, Hokkaido University, Sapporo 060-0810, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3161-1539","authenticated-orcid":false,"given":"Nakaji","family":"Tatsuro","sequence":"additional","affiliation":[{"name":"Field Science Center for Northern Biosphere, Hokkaido University, Sapporo 060-0809, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,10,31]]},"reference":[{"key":"ref_1","unstructured":"Japan Forestry Agency (2019). 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