{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,11]],"date-time":"2026-06-11T12:11:04Z","timestamp":1781179864682,"version":"3.54.1"},"reference-count":52,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2014,7,14]],"date-time":"2014-07-14T00:00:00Z","timestamp":1405296000000},"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>This study used a reef-up approach to map coral reef benthos, substrates and bathymetry, with high spatial resolution hyperspectral image data. It investigated  a physics-based inversion method for mapping coral reef benthos and substrates using readily available software: Hydrolight and ENVI. Compact Airborne Spectrographic Imager (CASI) data were acquired over Heron Reef in July 2002. The spectral reflectance of coral reef benthos and substrate types were measured in-situ, and using the HydroLight 4.2 radiative transfer model a spectral reflectance library of subsurface reflectance was simulated using water column depths from 0.5\u201310.0 m at 0.5 m intervals. Using the Spectral Angle Mapper algorithm, sediment, benthic micro-algae, algal turf, crustose coralline algae, macro-algae, and live coral were mapped with an overall accuracy of 65% to a depth of around 8.0 m; in waters deeper than 8.0 m the match between the classified image and field validation data was poor. Qualitative validation of the maps showed accurate mapping of areas dominated by sediment, benthic micro-algae, algal turf, live coral, and macro-algae. A bathymetric map was produced for water column depths 0.5\u201310.0 m, at 0.5 m intervals, and showed high correspondence with in-situ sonar data (R2 value of 0.93).<\/jats:p>","DOI":"10.3390\/rs6076423","type":"journal-article","created":{"date-parts":[[2014,7,14]],"date-time":"2014-07-14T11:33:53Z","timestamp":1405337633000},"page":"6423-6445","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":38,"title":["Mapping Coral Reef Benthos, Substrates, and Bathymetry, Using Compact Airborne Spectrographic Imager (CASI) Data"],"prefix":"10.3390","volume":"6","author":[{"given":"Ian","family":"Leiper","sequence":"first","affiliation":[{"name":"Centre for Spatial Environmental Research, School of Geography, Planning and Environmental Management, University of Queensland, St Lucia, QLD 4072, Australia"},{"name":"Research Institute for the Environment and Livelihoods, Charles Darwin University,  Casuarina Campus, Darwin, NT 0810, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2605-6104","authenticated-orcid":false,"given":"Stuart","family":"Phinn","sequence":"additional","affiliation":[{"name":"Centre for Spatial Environmental Research, School of Geography, Planning and Environmental Management, University of Queensland, St Lucia, QLD 4072, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chris","family":"Roelfsema","sequence":"additional","affiliation":[{"name":"Centre for Spatial Environmental Research, School of Geography, Planning and Environmental Management, University of Queensland, St Lucia, QLD 4072, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Karen","family":"Joyce","sequence":"additional","affiliation":[{"name":"Centre for Spatial Environmental Research, School of Geography, Planning and Environmental Management, University of Queensland, St Lucia, QLD 4072, Australia"},{"name":"Research Institute for the Environment and Livelihoods, Charles Darwin University,  Casuarina Campus, Darwin, NT 0810, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Arnold","family":"Dekker","sequence":"additional","affiliation":[{"name":"CSIRO Earth Observation & Informatics Future Science Platform, Canberra, ACT 2601, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2014,7,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1080\/08920759609362279","article-title":"A review of remote sensing for the assessment and management of tropical coastal resources","volume":"24","author":"Green","year":"1996","journal-title":"Coast. 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