{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,26]],"date-time":"2025-10-26T14:33:50Z","timestamp":1761489230799,"version":"build-2065373602"},"reference-count":13,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2013,10,15]],"date-time":"2013-10-15T00:00:00Z","timestamp":1381795200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Hyperspectral images represent an important source of information to assess ecosystem biodiversity. In particular, plant species richness is a primary indicator of biodiversity. This paper uses spectral variance to predict vegetation richness, known as Spectral Variation Hypothesis. Hierarchical agglomerative clustering is our primary tool to retrieve clusters whose Shannon entropy should reflect species richness on a given zone. However, in a high spectral mixing scenario, an additional unmixing step, just before entropy computation, is required; cluster centroids are enough for the unmixing process. Entropies computed using the proposed method correlate well with the ones calculated directly from synthetic and field data.<\/jats:p>","DOI":"10.3390\/s131013949","type":"journal-article","created":{"date-parts":[[2013,10,15]],"date-time":"2013-10-15T12:47:44Z","timestamp":1381841264000},"page":"13949-13959","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["Biodiversity Assessment Using Hierarchical Agglomerative Clustering and Spectral Unmixing over Hyperspectral Images"],"prefix":"10.3390","volume":"13","author":[{"given":"Ollantay","family":"Medina","sequence":"first","affiliation":[{"name":"Computing and Information Sciences and Engineering, University of Puerto Rico at Mayaguez, Call box 9000, Mayaguez 00681, Puerto Rico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Vidya","family":"Manian","sequence":"additional","affiliation":[{"name":"Department of Electrical & Computer Engineering, University of Puerto Rico at Mayaguez,  Call box 9000, Mayaguez 00681, Puerto Rico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"J.","family":"Chinea","sequence":"additional","affiliation":[{"name":"Department of Biology, University of Puerto Rico at Mayaguez, Call box 9000, Mayaguez 00681, Puerto Rico"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2013,10,15]]},"reference":[{"key":"ref_1","unstructured":"Palmer, M.W., Wohlgemuth, T., Earls, P., Ar\u00e9valo, J.R., and Thompson, S.D. 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Environ."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"318","DOI":"10.1016\/j.ecoinf.2010.06.001","article-title":"Remotely sensed spectral heterogeneity as a proxy of species diversity: Recent advances and open challenges","volume":"5","author":"Rocchini","year":"2010","journal-title":"Ecolo. Inform."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"83","DOI":"10.1007\/BF02985802","article-title":"The elements of statistical learning: Data mining, inference, and prediction","volume":"27","author":"Hastie","year":"2005","journal-title":"Math. Intell."},{"key":"ref_8","unstructured":"Salvador, S., and Chan, P. (2004, January 15\u201317). Determining the Number of Clusters\/Segments in Hierarchical Clustering\/Segmentation Algorithms. Boca Raton, FL, USA."},{"key":"ref_9","first-page":"59","article-title":"Thirteen ways to look at the correlation coefficient","volume":"42","author":"Nicewander","year":"1988","journal-title":"Am. 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Remote Sens."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/13\/10\/13949\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T21:49:51Z","timestamp":1760219391000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/13\/10\/13949"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2013,10,15]]},"references-count":13,"journal-issue":{"issue":"10","published-online":{"date-parts":[[2013,10]]}},"alternative-id":["s131013949"],"URL":"https:\/\/doi.org\/10.3390\/s131013949","relation":{},"ISSN":["1424-8220"],"issn-type":[{"type":"electronic","value":"1424-8220"}],"subject":[],"published":{"date-parts":[[2013,10,15]]}}}