Hoogenboom Mia, Rottier Cécile, Sikorski Severine, Ferrier-Pagès Christine
College of Marine and Environmental Sciences and ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Queensland 4811, Australia
Centre Scientifique de Monaco, 8 Quai Antoine 1er, MC98000, Monaco.
J Exp Biol. 2015 Dec;218(Pt 24):3866-77. doi: 10.1242/jeb.124396. Epub 2015 Oct 20.
The symbiosis between corals and dinoflagellates promotes the rapid growth of corals in shallow tropical oceans, and the high overall productivity of coral reefs. The aim of this study was to quantify and understand variation in carbon acquisition and allocation among coral species. We measured multiple physiological traits (including symbiont density, calcification, photosynthesis and tissue composition) for the same coral fragments to facilitate direct comparisons between species (Stylophora pistillata, Pocillopora damicornis, Galaxea fascicularis, Turbinaria reniformis and Acropora sp.). Tissue protein content was highly sensitive to the availability of particulate food, increasing in fed colonies of all species. Despite among-species variation in physiology, and consistent effects of feeding on some traits, overall energy allocation to tissue compared with skeleton growth did not depend on food availability. Extrapolating from our results, estimated whole-assemblage carbon uptake varied >20-fold across different coral assemblages, but this variation was largely driven by differences in the tissue surface area of different colony morphologies, rather than by differences in surface-area-specific physiological rates. Our results caution against drawing conclusions about reef productivity based solely on physiological rates measured per unit tissue surface area. Understanding the causes and consequences of among-species variation in physiological energetics provides insight into the mechanisms that underlie the fluxes of organic matter within reefs, and between reefs and the open ocean.
珊瑚与甲藻之间的共生关系促进了浅海热带海洋中珊瑚的快速生长以及珊瑚礁的高整体生产力。本研究的目的是量化并了解不同珊瑚物种在碳获取和分配方面的差异。我们对相同的珊瑚碎片测量了多个生理特征（包括共生体密度、钙化、光合作用和组织组成），以便于对不同物种（细枝鹿角珊瑚、鹿角杯形珊瑚、叉枝轴孔珊瑚、肾形真叶珊瑚和鹿角珊瑚属）进行直接比较。组织蛋白含量对颗粒食物的可利用性高度敏感，在所有物种的喂食群体中均有所增加。尽管物种间存在生理差异，且喂食对某些特征有一致的影响，但与骨骼生长相比，分配到组织的总能量并不取决于食物的可利用性。根据我们的结果推断，不同珊瑚组合的估计全组合碳吸收量相差超过20倍，但这种差异很大程度上是由不同群体形态的组织表面积差异驱动的，而非单位组织表面积特定生理速率的差异。我们的结果提醒人们，不要仅基于单位组织表面积测量的生理速率来得出关于珊瑚礁生产力的结论。了解生理能量学中物种间差异的原因和后果，有助于深入了解珊瑚礁内部以及珊瑚礁与开阔海洋之间有机物质通量的潜在机制。
