{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,18]],"date-time":"2026-01-18T00:25:34Z","timestamp":1768695934617,"version":"3.49.0"},"reference-count":48,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2023,9,2]],"date-time":"2023-09-02T00:00:00Z","timestamp":1693612800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"UoN GCRF grant \u2018Validation Sargassum detection\u2019"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>The bloom of pelagic Sargassum in the Atlantic Ocean has become increasingly problematic, especially when the algae have beached. A build-up of decaying beached material has damaging effects on coastal ecosystems and tourism industries. While remote sensing offers an effective tool to assess the spatial and temporal patterns of Sargassum over large spatial extents, its use so far has been limited to a broad discrimination of Sargassum species from other macroalgae and floating vegetation. Knowledge on the spatial distribution of decayed material will help to support management strategies and inform targeted removal. In this study, we aim to characterise the spectral response of fresh and decayed Sargassum and identify regions of the spectra that offer the greatest separability for the detection and classification of decayed material. We assessed the spectral response of fresh and decayed Sargassum (1) in situ on the beach and (2) in mesocosm experiments where Sargassum samples were allowed to decay over time. We found a decrease in the magnitude of reflectance, noticeably in the visible region (400\u2013700 nm), for decayed, in contrast to fresh, Sargassum. Separability analyses also showed that most spectral bands with a wavelength &gt; ~540 nm will be capable of discriminating between fresh and decayed material, although the near-infrared region offers the greatest degree of separability. We demonstrate, for the first time, that there are clear differences in the spectral reflectance of fresh and decayed Sargassum with potential application for remote sensing approaches.<\/jats:p>","DOI":"10.3390\/rs15174336","type":"journal-article","created":{"date-parts":[[2023,9,4]],"date-time":"2023-09-04T02:43:20Z","timestamp":1693795400000},"page":"4336","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Spectral Characteristics of Beached Sargassum in Response to Drying and Decay over Time"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9280-7244","authenticated-orcid":false,"given":"Chris J.","family":"Chandler","sequence":"first","affiliation":[{"name":"School of Geography, University of Nottingham, University Park, Nottingham NG7 2RD, UK"}]},{"given":"Silvia Valery","family":"\u00c1vila-Mosqueda","sequence":"additional","affiliation":[{"name":"Unidad Acad\u00e9mica de Sistemas Arrecifales, Instituto de Ciencias del Mar y Limnolog\u00eda, Universidad Nacional Aut\u00f3noma de M\u00e9xico, Puerto Morelos 77580, Mexico"}]},{"given":"Evelyn Raquel","family":"Salas-Acosta","sequence":"additional","affiliation":[{"name":"Unidad Acad\u00e9mica de Sistemas Arrecifales, Instituto de Ciencias del Mar y Limnolog\u00eda, Universidad Nacional Aut\u00f3noma de M\u00e9xico, Puerto Morelos 77580, Mexico"}]},{"given":"Eden","family":"Maga\u00f1a-Gallegos","sequence":"additional","affiliation":[{"name":"Unidad Acad\u00e9mica de Sistemas Arrecifales, Instituto de Ciencias del Mar y Limnolog\u00eda, Universidad Nacional Aut\u00f3noma de M\u00e9xico, Puerto Morelos 77580, Mexico"}]},{"given":"Edgar Escalante","family":"Mancera","sequence":"additional","affiliation":[{"name":"Unidad Acad\u00e9mica de Sistemas Arrecifales, Instituto de Ciencias del Mar y Limnolog\u00eda, Universidad Nacional Aut\u00f3noma de M\u00e9xico, Puerto Morelos 77580, Mexico"}]},{"given":"Miguel Angel G\u00f3mez","family":"Reali","sequence":"additional","affiliation":[{"name":"Unidad Acad\u00e9mica de Sistemas Arrecifales, Instituto de Ciencias del Mar y Limnolog\u00eda, Universidad Nacional Aut\u00f3noma de M\u00e9xico, Puerto Morelos 77580, Mexico"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5642-8215","authenticated-orcid":false,"given":"Betsab\u00e9","family":"de la Barreda-Bautista","sequence":"additional","affiliation":[{"name":"School of Geography, University of Nottingham, University Park, Nottingham NG7 2RD, UK"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3040-552X","authenticated-orcid":false,"given":"Doreen S.","family":"Boyd","sequence":"additional","affiliation":[{"name":"School of Geography, University of Nottingham, University Park, Nottingham NG7 2RD, UK"}]},{"given":"Sarah E.","family":"Metcalfe","sequence":"additional","affiliation":[{"name":"School of Geography, University of Nottingham, University Park, Nottingham NG7 2RD, UK"}]},{"given":"Sofie","family":"Sjogersten","sequence":"additional","affiliation":[{"name":"School of Biosciences, University of Nottingham, College Road, Sutton Bonington, Loughborough, Leicestershire LE12 5RD, UK"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6447-7479","authenticated-orcid":false,"given":"Brigitta","family":"van Tussenbroek","sequence":"additional","affiliation":[{"name":"Unidad Acad\u00e9mica de Sistemas Arrecifales, Instituto de Ciencias del Mar y Limnolog\u00eda, Universidad Nacional Aut\u00f3noma de M\u00e9xico, Puerto Morelos 77580, Mexico"}]},{"given":"Rodolfo","family":"Silva","sequence":"additional","affiliation":[{"name":"Instituto de Ingenier\u00eda, Universidad Nacional Aut\u00f3noma de M\u00e9xico, Mexico City 04510, Mexico"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6464-3054","authenticated-orcid":false,"given":"Giles M.","family":"Foody","sequence":"additional","affiliation":[{"name":"School of Geography, University of Nottingham, University Park, Nottingham NG7 2RD, UK"}]}],"member":"1968","published-online":{"date-parts":[[2023,9,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"477","DOI":"10.1007\/s11284-011-0821-8","article-title":"\u2018Green tides\u2019 are overwhelming the coastline of our blue planet: Taking the world\u2019s largest example","volume":"26","author":"Ye","year":"2011","journal-title":"Ecol. 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