Spectral discrimination of coral mortality states following a severe bleaching event |
| |
Authors: | C D Clark P J Mumby J R M Chisholm J Jaubert S Andrefouet |
| |
Affiliation: | 1. Sheffield Centre for Earth Observation Science , University of Sheffield , Sheffield, England, UK;2. Centre for Tropical Coastal Management Studies , The University , Ridley Building, Newcastle upon Tyne, England, UK;3. Observatoire Oceanologique Europeen , Centre Scientifique de Monaco , Principality of Monaco, Avenue Saint-Martin, MC 98000;4. Department of Marine Science , University of South Florida , 140, 7th Avenue South, St Petersburg, FL, 33701, USA |
| |
Abstract: | Although relatively easy to distinguish the spectra of bleached and living coral, once corals have died their skeletons remained bleached (white) for only a short period. Rapid colonisation by algae can give rise to pigmentation that may be similar to that of living coral. Thus, by the time remotely sensed imagery has been acquired, discrimination of live and dead corals is no longer facile. Field measurements of spectral reflectance of live and algal-colonised dead corals (arising from different mortality events) were made in French Polynesia. Derivative analysis revealed wavelengths and slope characteristics that could be used to discriminate between mortality states with an accuracy of ~ 85%. These results encourage application of hyperspectral remote sensing to quantitatively assess the extent of coral bleaching events. |
| |
Keywords: | |
|
|