Coral skeletons defend against ultraviolet radiation.
BACKGROUND: Many coral reef organisms are photosynthetic or have evolved in tight symbiosis with photosynthetic symbionts. As such, the tissues of reef organisms are often exposed to intense solar radiation in clear tropical waters and have adapted to trap and harness photosynthetically active radia...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
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Public Library of Science (PLoS)
2009-01-01
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| Series: | PLoS ONE |
| Online Access: | http://europepmc.org/articles/PMC2776492?pdf=render |
| _version_ | 1818267363939713024 |
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| author | Ruth Reef Paulina Kaniewska Ove Hoegh-Guldberg |
| author_facet | Ruth Reef Paulina Kaniewska Ove Hoegh-Guldberg |
| author_sort | Ruth Reef |
| collection | DOAJ |
| description | BACKGROUND: Many coral reef organisms are photosynthetic or have evolved in tight symbiosis with photosynthetic symbionts. As such, the tissues of reef organisms are often exposed to intense solar radiation in clear tropical waters and have adapted to trap and harness photosynthetically active radiation (PAR). High levels of ultraviolet radiation (UVR) associated with sunlight, however, represent a potential problem in terms of tissue damage. METHODOLOGY/PRINCIPAL FINDINGS: By measuring UVR and PAR reflectance from intact and ground bare coral skeletons we show that the property of calcium carbonate skeletons to absorb downwelling UVR to a significant extent, while reflecting PAR back to the overlying tissue, has biological advantages. We placed cnidarians on top of bare skeletons and a UVR reflective substrate and showed that under ambient UVR levels, UVR transmitted through the tissues of cnidarians placed on top of bare skeletons were four times lower compared to their counterparts placed on a UVR reflective white substrate. In accordance with the lower levels of UVR measured in cnidarians on top of coral skeletons, a similar drop in UVR damage to their DNA was detected. The skeletons emitted absorbed UVR as yellow fluorescence, which allows for safe dissipation of the otherwise harmful radiation. CONCLUSIONS/SIGNIFICANCE: Our study presents a novel defensive role for coral skeletons and reveals that the strong UVR absorbance by the skeleton can contribute to the ability of corals, and potentially other calcifiers, to thrive under UVR levels that are detrimental to most marine life. |
| first_indexed | 2024-12-12T20:21:25Z |
| format | Article |
| id | doaj.art-68bd379ecc6547dd8faffeac8565e569 |
| institution | Directory Open Access Journal |
| issn | 1932-6203 |
| language | English |
| last_indexed | 2024-12-12T20:21:25Z |
| publishDate | 2009-01-01 |
| publisher | Public Library of Science (PLoS) |
| record_format | Article |
| series | PLoS ONE |
| spelling | doaj.art-68bd379ecc6547dd8faffeac8565e5692022-12-22T00:13:14ZengPublic Library of Science (PLoS)PLoS ONE1932-62032009-01-01411e799510.1371/journal.pone.0007995Coral skeletons defend against ultraviolet radiation.Ruth ReefPaulina KaniewskaOve Hoegh-GuldbergBACKGROUND: Many coral reef organisms are photosynthetic or have evolved in tight symbiosis with photosynthetic symbionts. As such, the tissues of reef organisms are often exposed to intense solar radiation in clear tropical waters and have adapted to trap and harness photosynthetically active radiation (PAR). High levels of ultraviolet radiation (UVR) associated with sunlight, however, represent a potential problem in terms of tissue damage. METHODOLOGY/PRINCIPAL FINDINGS: By measuring UVR and PAR reflectance from intact and ground bare coral skeletons we show that the property of calcium carbonate skeletons to absorb downwelling UVR to a significant extent, while reflecting PAR back to the overlying tissue, has biological advantages. We placed cnidarians on top of bare skeletons and a UVR reflective substrate and showed that under ambient UVR levels, UVR transmitted through the tissues of cnidarians placed on top of bare skeletons were four times lower compared to their counterparts placed on a UVR reflective white substrate. In accordance with the lower levels of UVR measured in cnidarians on top of coral skeletons, a similar drop in UVR damage to their DNA was detected. The skeletons emitted absorbed UVR as yellow fluorescence, which allows for safe dissipation of the otherwise harmful radiation. CONCLUSIONS/SIGNIFICANCE: Our study presents a novel defensive role for coral skeletons and reveals that the strong UVR absorbance by the skeleton can contribute to the ability of corals, and potentially other calcifiers, to thrive under UVR levels that are detrimental to most marine life.http://europepmc.org/articles/PMC2776492?pdf=render |
| spellingShingle | Ruth Reef Paulina Kaniewska Ove Hoegh-Guldberg Coral skeletons defend against ultraviolet radiation. PLoS ONE |
| title | Coral skeletons defend against ultraviolet radiation. |
| title_full | Coral skeletons defend against ultraviolet radiation. |
| title_fullStr | Coral skeletons defend against ultraviolet radiation. |
| title_full_unstemmed | Coral skeletons defend against ultraviolet radiation. |
| title_short | Coral skeletons defend against ultraviolet radiation. |
| title_sort | coral skeletons defend against ultraviolet radiation |
| url | http://europepmc.org/articles/PMC2776492?pdf=render |
| work_keys_str_mv | AT ruthreef coralskeletonsdefendagainstultravioletradiation AT paulinakaniewska coralskeletonsdefendagainstultravioletradiation AT ovehoeghguldberg coralskeletonsdefendagainstultravioletradiation |