{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,25]],"date-time":"2026-02-25T20:23:01Z","timestamp":1772050981950,"version":"3.50.1"},"reference-count":46,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2012,11,13]],"date-time":"2012-11-13T00:00:00Z","timestamp":1352764800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Mapping the spatial distribution of plant species in savannas provides insight into the roles of competition, fire, herbivory, soils and climate in maintaining the biodiversity of these ecosystems. This study focuses on the challenges facing large-scale species mapping using a fusion of Light Detection and Ranging (LiDAR) and hyperspectral imagery. Here we build upon previous work on airborne species detection by using a two-stage support vector machine (SVM) classifier to first predict species from hyperspectral data at the pixel scale. Tree crowns are segmented from the lidar imagery such that crown-level information, such as maximum tree height, can then be combined with the pixel-level species probabilities to predict the species of each tree. An overall prediction accuracy of 76% was achieved for 15 species. We also show that bidirectional reflectance distribution (BRDF) effects caused by anisotropic scattering properties of savanna vegetation can result in flight line artifacts evident in species probability maps, yet these can be largely mitigated by applying a semi-empirical BRDF model to the hyperspectral data. We find that confronting these three challenges\u2014reflectance anisotropy, integration of pixel- and crown-level data, and crown delineation over large areas\u2014enables species mapping at ecosystem scales for monitoring biodiversity and ecosystem function.<\/jats:p>","DOI":"10.3390\/rs4113462","type":"journal-article","created":{"date-parts":[[2012,11,13]],"date-time":"2012-11-13T11:17:36Z","timestamp":1352805456000},"page":"3462-3480","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":186,"title":["Mapping Savanna Tree Species at Ecosystem Scales Using Support Vector Machine Classification and BRDF Correction on Airborne Hyperspectral and LiDAR Data"],"prefix":"10.3390","volume":"4","author":[{"given":"Matthew S.","family":"Colgan","sequence":"first","affiliation":[{"name":"Department of Global Ecology, Carnegie Institution for Science, Stanford 94305, CA, USA"}]},{"given":"Claire A.","family":"Baldeck","sequence":"additional","affiliation":[{"name":"Department of Global Ecology, Carnegie Institution for Science, Stanford 94305, CA, USA"}]},{"given":"Jean-Baptiste","family":"F\u00e9ret","sequence":"additional","affiliation":[{"name":"Department of Global Ecology, Carnegie Institution for Science, Stanford 94305, CA, USA"}]},{"given":"Gregory P.","family":"Asner","sequence":"additional","affiliation":[{"name":"Department of Global Ecology, Carnegie Institution for Science, Stanford 94305, CA, USA"}]}],"member":"1968","published-online":{"date-parts":[[2012,11,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Scholes, R.J., and Walker, B.H. 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Opt"}],"container-title":["Remote Sensing"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-4292\/4\/11\/3462\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T21:53:32Z","timestamp":1760219612000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-4292\/4\/11\/3462"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2012,11,13]]},"references-count":46,"journal-issue":{"issue":"11","published-online":{"date-parts":[[2012,11]]}},"alternative-id":["rs4113462"],"URL":"https:\/\/doi.org\/10.3390\/rs4113462","relation":{},"ISSN":["2072-4292"],"issn-type":[{"value":"2072-4292","type":"electronic"}],"subject":[],"published":{"date-parts":[[2012,11,13]]}}}