Spectral reflectance of Palauan reef-building coral with different symbionts in response to elevated temperature
Russell, B.; Dierssen, H.; LaJeunesse, T.; Hoadley, K.; Warner, M.; Kemp, D.; Bateman, T. (2016). Spectral reflectance of Palauan reef-building coral with different symbionts in response to elevated temperature. Remote Sens. 8(3): 164. https://dx.doi.org/10.3390/rs8030164 In: Remote Sensing. MDPI: Basel. ISSN 2072-4292; e-ISSN 2072-4292, more |   |
| Keywords | Cyphastrea serailia (Forskål, 1775) [WoRMS]; Pachyseris rugosa (Lamarck, 1801) [WoRMS]; Symbiodinium trenchii LaJeunesse, 2014 [WoRMS]
Marine/Coastal | | Author keywords | coral reef; reflectance spectroscopy; Symbiodinium trenchii; Cyphastrea serailia; Pachyseris rugosa; hyperspectral imaging; coral bleaching |
| Authors | | Top | - Russell, B.
- Dierssen, H., more
- LaJeunesse, T.
- Hoadley, K.
| - Warner, M.
- Kemp, D.
- Bateman, T.
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| Abstract | Spectral reflectance patterns of corals are driven largely by the pigments of photosynthetic symbionts within the host cnidarian. The warm inshore bays and cooler offshore reefs of Palau share a variety of coral species with differing endosymbiotic dinoflagellates (genus: Symbiodinium), with the thermally tolerant Symbiodinium trenchii (S. trenchii) (= type D1a or D1-4) predominating under the elevated temperature regimes inshore, and primarily Clade C types in the cooler reefs offshore. Spectral reflectance of two species of stony coral, Cyphastrea serailia (C. serailia) and Pachyseris rugosa (P. rugosa), from both inshore and offshore locations shared multiple features both between sites and to similar global data from other studies. No clear reflectance features were evident which might serve as markers of thermally tolerant S. trenchii symbionts compared to the same species of coral with different symbionts. Reflectance from C. serailia colonies from inshore had a fluorescence peak at approximately 500 nm which was absent from offshore animals. Integrated reflectance across visible wavelengths had an inverse correlation to symbiont cell density and could be used as a relative indicator of the symbiont abundance for each type of coral. As hypothesized, coral colonies from offshore with Clade C symbionts showed a greater response to experimental heating, manifested as decreased symbiont density and increased reflectance or “bleaching” than their inshore counterparts with S. trenchii. Although no unique spectral features were found to distinguish species of symbiont, spectral differences related to the abundance of symbionts could prove useful in field and remote sensing studies. |
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