Department of Biology, University of Texas at Arlington, Arlington, TX 76019, USA.
J Exp Biol. 2010 Mar 15;213(6):934-45. doi: 10.1242/jeb.037580.
Coral mortality due to climate-associated stress is likely to increase as the oceans get warmer and more acidic. Coral bleaching and an increase in infectious disease are linked to above average sea surface temperatures. Despite the uncertain future for corals, recent studies have revealed physiological mechanisms that improve coral resilience to the effects of climate change. Some taxa of bleached corals can increase heterotrophic food intake and exchange symbionts for more thermally tolerant clades; this plasticity can increase the probability of surviving lethal thermal stress. Corals can fight invading pathogens with a suite of innate immune responses that slow and even arrest pathogen growth and reduce further tissue damage. Several of these responses, such as the melanin cascade, circulating amoebocytes and antioxidants, are induced in coral hosts during pathogen invasion or disease. Some components of immunity show thermal resilience and are enhanced during temperature stress and even in bleached corals. These examples suggest some plasticity and resilience to cope with environmental change and even the potential for evolution of resistance to disease. However, there is huge variability in responses among coral species, and the rate of climate change is projected to be so rapid that only extremely hardy taxa are likely to survive the projected changes in climate stressors.
由于与气候相关的压力，珊瑚的死亡率可能会增加，因为海洋会变得更温暖和更具酸性。珊瑚白化和传染病的增加与高于平均海面温度有关。尽管珊瑚的未来不确定，但最近的研究揭示了改善珊瑚对气候变化影响的恢复力的生理机制。一些白化珊瑚的分类群可以增加异养食物的摄入，并将共生体交换为更耐热的进化枝；这种可塑性可以增加在致命热应力下生存的可能性。珊瑚可以通过一系列先天免疫反应来对抗入侵的病原体，这些反应可以减缓甚至阻止病原体的生长并减少进一步的组织损伤。在病原体入侵或疾病期间，珊瑚宿主中会诱导几种这样的反应，如黑色素级联、循环变形细胞和抗氧化剂。免疫的一些成分具有耐热性，并在温度胁迫下甚至在白化珊瑚中增强。这些例子表明，珊瑚具有一定的可塑性和恢复力，可以应对环境变化，甚至有可能对疾病产生抗性。然而，珊瑚物种之间的反应存在巨大的可变性，预计气候变化的速度如此之快，只有极其耐寒的分类群才有可能在预期的气候压力变化中存活下来。
