文章基本信息

标题：Seychelles Lagoon Provides Corals with a Refuge from Bleaching
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作者：David Iluz ; Razi Vago ; Nanette E. Chadwick 等
期刊名称：International Journal of Ecology
印刷版ISSN：1687-9708
电子版ISSN：1687-9716
出版年度：2008
卷号：2008
DOI：10.1155/2008/281038
出版社：Hindawi Publishing Corporation
摘要：An extensive bleaching event in the summer of the year 1997-1998 affected most reefs along East Africa's shores. In the aftermath of that episode, the reefs of Île Alphonse in the Seychelles were examined and it was found that reefs along the seaward slopes of the island lost >95% of their branching coral colonies, with considerably higher survival of massive species. Île Alphonse features a nearly circular shallow lagoon, with steep seaward slopes. Contrary to our expectations, mortality in the warmer lagoon was far lower than of coral colonies on the surrounding slopes, bathed in deeper and cooler waters. We suggest that corals in the lagoon were protected from UV radiation by leachate stemming from seagrass leaves steeped in the lagoon. Our measurements in the lagoon showed a strong attenuation of ultraviolet radiation, not observed in the waters outside the lagoon, and laboratory examination confirmed that the strong UV absorption of substances leached into seawater from decomposing leaves of the seagrass Thalassodendron (=Cymodocea) testudinaceum. Our findings demonstrate the synergism between elevated seawater temperature and UV radiation in triggering bleaching on shallow reefs.