Endolithic algae: an alternative source of photoassimilates during coral bleaching
Endolithic algae: an alternative source of photoassimilates during coral bleaching
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DOI：
10.1098/rspb.2002.1983
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发表时间：
2002-06-22
影响因子：
4.7
通讯作者：
Loya, Y
中科院分区：
文献类型：
--
作者：
Fine, M;Loya, Y
最近关于世界范围内珊瑚白化事件导致毁灭性珊瑚死亡的报告引起了科学家和资源管理人员的警觉。珊瑚物种因白化事件而出现的生存差异已得到广泛记录。我们认为，在可能的因素，有助于生存的珊瑚物种在这种事件中的石内藻类窝藏在他们的骨架，提供了一种替代能源。我们研究了在整个漂白事件的结壳珊瑚Oculinapatagonica的骨架中的光合色素浓度和生物量的动态。在反复的夏季漂白事件，这些石内藻类获得增加的光合有效辐射，生物量显着增加，并产生越来越多的光合同化物，这是易位到珊瑚。在相对健康的群体骨骼中，叶绿素浓度和内体生物量分别为4.6 +/- 1.57和1570 +/- 427 mug cm（-2（0-40%漂白），但分别高达14.8 +/- 2.5和4036 +/- 764 mug cm（-2）的内岩叶绿素和生物量，在漂白菌落的骨骼中（大于40%漂白）。14 C-标记的光合同化物的易位动力学漂白珊瑚组织的内载物显示显着更高的14 C活性的内载物内的骨骼漂白珊瑚比内载物在非漂白珊瑚。这种替代能源可能对O. Patagonica，允许虫黄藻的逐渐招募和随后的冬季恢复。
Recent reports of worldwide coral bleaching events leading to devastating coral mortality have caused alarm among scientists and resource managers. Differential survival of coral species through bleaching events has been widely documented. We suggest that among the possible factors contributing to survival of coral species during such events are endolithic algae harboured in their skeleton, providing an alternative source of energy. We studied the dynamics of photosynthetic pigment concentrations and biomass of endoliths in the skeleton of the encrusting coral Oculina patagonica throughout a bleaching event. During repeated summer bleaching events these endolithic algae receive increased photosynthetically active radiation, increase markedly in biomass, and produce increasing amounts of photoassimilates, which are translocated to the coral. Chlorophyll concentrations and biomass of endoliths were 4.6 +/- 1.57 and 1570 +/- 427 mug cm(-2) respectively, in skeletons of relatively healthy colonies (0-40% bleaching) but up to 14.8 +/- 2.5 and 4036 +/- 764 mug cm(-2) endolith chlorophyll and biomass respectively, in skeletons of bleached colonies (greater than 40% bleaching). The translocation dynamics of 14 C-labelled photoassimilates from the endoliths to bleached coral tissue showed significantly higher 14 C activity of the endoliths harboured within the skeletons of bleached corals than that of the endoliths in non-bleached corals. This alternative source of energy may be vital for the survivorship of O. patagonica, allowing gradual recruitment of zooxanthellae and subsequent recovery during the following winter.