Global change, including rising temperatures and acidification, threatens corals globally. Although bleaching events reveal fine-scale patterns of resilience, traits enabling persistence under global change remain elusive. We conducted a 95-d controlled-laboratory experiment investigating how duration of exposure to warming (~28, 31°C), acidification (pCO₂ ~ 343 [present day], ~663 [end of century], ~3109 [extreme] μatm), and their combination influences physiology of reef-building corals (Siderastrea siderea, Pseudodiploria strigosa) from two reef zones on the Belize Mesoamerican Barrier Reef System. Every 30 d, net calcification rate, host protein and carbohydrate, chlorophyll a, and symbiont density were quantified for the same coral individual to characterize acclimation potential under global change. Coral physiologies of the two species were differentially affected by stressors and exposure duration was found to modulate these responses. Siderastrea siderea exhibited resistance to end of century pCO₂ and temperature stress, but calcification was negatively affected by extreme pCO₂. However, S. siderea calcification rates remained positive after 95 d of extreme pCO₂ conditions, suggesting acclimation. In contrast, P. strigosa was more negatively influenced by elevated temperatures, which reduced most physiological parameters. An exception was nearshore P. strigosa, which maintained calcification rates under elevated temperature, suggesting local adaptation to the warmer environment of their natal reef zone. This work highlights how tracking coral physiology across various exposure durations can capture acclimatory responses to global change stressors.

中文翻译：

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暴露时间调节加勒比珊瑚对全球变化压力源的反应

全球变化，包括气温上升和酸化，威胁着全球的珊瑚。尽管白化事件揭示了韧性的精细模式，但在全球变化下能够持续存在的特征仍然难以捉摸。我们进行了一项为期 95 天的受控实验室实验，研究暴露于变暖 (~28, 31°C)、酸化 ( p CO ₂  ~ 343 [今天]、~663 [世纪末]、~3109 [极端] μ atm），以及它们的组合影响来自伯利兹中美洲堡礁系统两个珊瑚礁区的造礁珊瑚（Siderastrea siderea、Pseudodiploria strigosa）的生理学。每 30 d，净钙化率、宿主蛋白质和碳水化合物、叶绿素a，并对同一珊瑚个体的共生体密度进行量化，以表征全球变化下的适应潜力。这两个物种的珊瑚生理受压力因素的影响不同，并且发现暴露时间可以调节这些反应。Siderastrea siderea表现出对世纪末p CO ₂和温度胁迫的抵抗力，但钙化受到极端p CO _{2 的}负面影响。然而，在极端p CO ₂条件下95天后，S. siderea钙化率仍为正值，表明已适应环境。相比之下，P. strigosa受高温的负面影响更大，这降低了大多数生理参数。一个例外是近岸P. strigosa，它在升高的温度下保持钙化率，表明当地适应了其出生礁区较温暖的环境。这项工作强调了跟踪不同暴露持续时间的珊瑚生理学如何捕捉对全球变化压力源的适应反应。