{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,26]],"date-time":"2026-03-26T22:10:45Z","timestamp":1774563045867,"version":"3.50.1"},"reference-count":43,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2018,8,5]],"date-time":"2018-08-05T00:00:00Z","timestamp":1533427200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001655","name":"Deutscher Akademischer Austauschdienst","doi-asserted-by":"publisher","award":["57186656"],"award-info":[{"award-number":["57186656"]}],"id":[{"id":"10.13039\/501100001655","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Seagrasses are traversing the epoch of intense anthropogenic impacts that significantly decrease their coverage and invaluable ecosystem services, necessitating accurate and adaptable, global-scale mapping and monitoring solutions. Here, we combine the cloud computing power of Google Earth Engine with the freely available Copernicus Sentinel-2 multispectral image archive, image composition, and machine learning approaches to develop a methodological workflow for large-scale, high spatiotemporal mapping and monitoring of seagrass habitats. The present workflow can be easily tuned to space, time and data input; here, we show its potential, mapping 2510.1 km2 of P. oceanica seagrasses in an area of 40,951 km2 between 0 and 40 m of depth in the Aegean and Ionian Seas (Greek territorial waters) after applying support vector machines to a composite of 1045 Sentinel-2 tiles at 10-m resolution. The overall accuracy of P. oceanica seagrass habitats features an overall accuracy of 72% following validation by an independent field data set to reduce bias. We envision that the introduced flexible, time- and cost-efficient cloud-based chain will provide the crucial seasonal to interannual baseline mapping and monitoring of seagrass ecosystems in global scale, resolving gain and loss trends and assisting coastal conservation, management planning, and ultimately climate change mitigation.<\/jats:p>","DOI":"10.3390\/rs10081227","type":"journal-article","created":{"date-parts":[[2018,8,7]],"date-time":"2018-08-07T03:44:18Z","timestamp":1533613458000},"page":"1227","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":157,"title":["Towards Global-Scale Seagrass Mapping and Monitoring Using Sentinel-2 on Google Earth Engine: The Case Study of the Aegean and Ionian Seas"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0766-7986","authenticated-orcid":false,"given":"Dimosthenis","family":"Traganos","sequence":"first","affiliation":[{"name":"German Aerospace Center (DLR), Remote Sensing Technology Institute, Rutherfordstra\u00dfe 2, 12489 Berlin, Germany"}]},{"given":"Bharat","family":"Aggarwal","sequence":"additional","affiliation":[{"name":"German Aerospace Center (DLR), Remote Sensing Technology Institute, Rutherfordstra\u00dfe 2, 12489 Berlin, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3228-280X","authenticated-orcid":false,"given":"Dimitris","family":"Poursanidis","sequence":"additional","affiliation":[{"name":"Foundation for Research and Technology\u2014Hellas (FORTH), Institute of Applied and Computational Mathematics, N. Plastira 100, Vassilika Vouton, 70013 Heraklion, Greece"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1916-1600","authenticated-orcid":false,"given":"Konstantinos","family":"Topouzelis","sequence":"additional","affiliation":[{"name":"Department of Marine Science, University of the Aegean, University Hill, 81100 Mytilene, Greece"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5208-626X","authenticated-orcid":false,"given":"Nektarios","family":"Chrysoulakis","sequence":"additional","affiliation":[{"name":"Foundation for Research and Technology\u2014Hellas (FORTH), Institute of Applied and Computational Mathematics, N. Plastira 100, Vassilika Vouton, 70013 Heraklion, Greece"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8122-1475","authenticated-orcid":false,"given":"Peter","family":"Reinartz","sequence":"additional","affiliation":[{"name":"German Aerospace Center (DLR), Earth Observation Center (EOC), 82234 We\u00dfling, Germany"}]}],"member":"1968","published-online":{"date-parts":[[2018,8,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"3","DOI":"10.1016\/j.jembe.2007.06.012","article-title":"Global seagrass distribution and diversity: A bioregional model","volume":"350","author":"Short","year":"2007","journal-title":"J. Exp. Mar. Biol. Ecol."},{"key":"ref_2","unstructured":"Green, E.P., and Short, F.T. (2003). World Atlas of Seagrasses, University of California Press."},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Polunin, N. (2008). Seagrass Ecosystems: Their Global Status and Prospects. 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