Juveniles of the Atlantic coral, Favia fragum (Esper, 1797) do not invest energy to maintain calcification under ocean acidification
Juveniles of the Atlantic coral, Favia fragum (Esper, 1797) do not invest energy to maintain calcification under ocean acidification
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DOI：
10.1016/j.jembe.2018.07.007
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发表时间：
2018-10-01
影响因子：
2
通讯作者：
Repeta, Daniel J.
中科院分区：
文献类型：
--
作者：
Drenkard, Elizabeth J.;Cohen, Anne L.;Repeta, Daniel J.
海洋酸化通过减缓钙化和促进钙化生物和沉积物的溶解来威胁珊瑚礁生态系统。然而，包括珊瑚宿主的营养状况在内的多种因素已被证明调节了骨性关节炎对钙化的影响。在三个不同的实验中，我们将大西洋高尔夫球珊瑚Favia Fragum的幼体暴露在高浓度的二氧化碳和不同的营养(光照或摄食)条件下。无论二氧化碳水平如何，从平纹夜蛾幼虫饲养的幼虫明显更大，并且在摄食时产生更多的碳酸钙。然而，无论摄食条件如何，受到高二氧化碳影响的珊瑚每毫米产生的CaCO3都较少。此外，在较高光照水平下饲养的未摄食珊瑚表现出较低的叶绿素a和较高的总脂含量，但光照对珊瑚钙化没有显著影响。相反，无论光照条件如何，二氧化碳浓度升高对钙化都有显著的负面影响，但对生理组织参数没有明显影响。我们的结果表明，幼体碎裂镰刀菌的钙化对OA的敏感性既不受光的调节，也不受摄食的调节，尽管生理指标表明营养状况得到了改善。这表明，珊瑚不一定会转移能量来维持高二氧化碳下的钙化，即使它们有足够的能量资源这样做。
Ocean acidification (OA) threatens coral reef ecosystems by slowing calcification and enhancing dissolution of calcifying organisms and sediments. Nevertheless, multiple factors have been shown to modulate OA's impact on calcification, including the nutritional status of the coral host. In three separate experiments, we exposed juveniles of the Atlantic golf ball coral, Favia fragum, to elevated CO2 and varied nutritional (light or feeding) conditions. Juveniles reared from planulae larvae were significantly larger and produced more CaCO3 when fed, regardless of CO2 level. However, corals subjected to elevated CO2 produced less CaCO3 per mm(2) regardless of feeding condition. Additionally, unfed corals reared under elevated light levels exhibited lower chlorophyll a and higher total lipid content, but light had no significant effect on coral calcification. Conversely, elevated CO2 had a significant, negative affect on calcification, regardless of light condition but no detectable effect on physiological tissue parameters. Our results indicate that the sensitivity of juvenile F. fragum calcification to OA was neither modulated by light nor by feeding, despite physiological indications of enhanced nutritional status. This suggests that corals do not necessarily divert energy to maintain calcification under high CO2, even when they have the energetic resources to do so.