The effects of prolonged “bleaching” on the tissue biomass and reproduction of the reef coral Montastrea annularis
The effects of prolonged “bleaching” on the tissue biomass and reproduction of the reef coral Montastrea annularis
复制标题
长期“白化”对环山珊瑚礁珊瑚组织生物量和繁殖的影响
作者：
A. Szmant;N. Gassman
从Carysfort礁，佛罗里达，仍然漂白七个月后，1987年加勒比漂白事件的Montastrea annularis殖民地进行了研究，以确定漂白对珊瑚生理的长期影响。发现两种类型的漂白菌落：具有正常色素含量的低数量的虫黄藻的菌落，和具有高密度的低色素虫黄藻的菌落。在这两种类型中，虫黄藻在息肉组织中的分布异常：最高密度在基底内胚层和肠系膜中观察到，其中虫黄藻通常不存在。漂白珊瑚的每骨骼表面积的组织碳和组织氮生物量减少30%和44%，但与其他没有漂白（正常）或漂白并恢复其虫黄藻（恢复）的菌落相同的组织C：N比。漂白珊瑚在漂白后的繁殖季节无法完成配子发生，而恢复的珊瑚则能够遵循正常的配子发生周期。漂白珊瑚似乎能够在没有虫黄藻营养贡献的情况下通过消耗自身的结构材料来维持长期生存，但没有繁殖所需的资源。另一方面，恢复的珊瑚一定在漂白事件后不久就恢复了虫黄藻，因为它们的组织生物量和繁殖能力都没有受到损害。
Colonies of Montastrea annularis from Carysfort Reef, Florida, that remained bleached seven months after the 1987 Caribbean bleaching event were studied to determine the long term effects of bleaching on coral physiology. Two types of bleached colonies were found: colonies with low numbers of zooxanthellae with normal pigment content, and a colony with high densities of lowpigment zooxanthellae. In both types, the zooxanthellae had an abnormal distribution within polyp tissues: highest densities were observed in basal endoderm and in mesenteries where zooxanthellae are not normally found. Bleached corals had 30% less tissue carbon and 44% less tissue nitrogen biomass per skeletal surface area, but the same tissue C:N ratio as other colonies that either did not bleach (normal) or that bleached and regained their zooxanthellae (recovered). Bleached corals were not able to complete gametogenesis during the reproductive season following the bleaching, while recovered corals were able to follow a normal gametogenic cycle. It appears that bleached corals were able to survive the prolonged period without nutritional contribution from their zooxanthellae by consuming their own structural materials for maintenance, but then, did not have the resources necessary for reproduction. The recovered corals, on the other hand, must have regained their zooxanthellae soon after the bleaching event since neither their tissue biomass nor their ability to reproduce were impaired.