Walker Nia S, Nestor Victor, Golbuu Yimnang, Palumbi Stephen R
Department of Biology Hopkins Marine Station of Stanford University Pacific Grove California USA.
Hawai'i Institute of Marine Biology University of Hawai'i at Mānoa Kāne'ohe Hawaii USA.
Evol Appl. 2022 Nov 7;16(2):504-517. doi: 10.1111/eva.13500. eCollection 2023 Feb.
The prevalence of global coral bleaching has focused much attention on the possibility of interventions to increase heat resistance. However, if high heat resistance is linked to fitness tradeoffs that may disadvantage corals in other areas, then a more holistic view of heat resilience may be beneficial. In particular, overall resilience of a species to heat stress is likely to be the product of both resistance to heat and recovery from heat stress. Here, we investigate heat resistance and recovery among individual colonies in Palau. We divided corals into low, moderate, and high heat resistance categories based on the number of days (4-9) needed to reach significant pigmentation loss due to experimental heat stress. Afterward, we deployed corals back onto a reef in a common garden 6-month recovery experiment that monitored chlorophyll , mortality, and skeletal growth. Heat resistance was negatively correlated with mortality during early recovery (0-1 month) but not late recovery (4-6 months), and chlorophyll concentration recovered in heat-stressed corals by 1-month postbleaching. However, moderate-resistance corals had significantly greater skeletal growth than high-resistance corals by 4 months of recovery. High- and low-resistance corals on average did not exhibit skeletal growth within the observed recovery period. These data suggest complex tradeoffs may exist between coral heat resistance and recovery and highlight the importance of incorporating multiple aspects of resilience into future reef management programs.
全球珊瑚白化的普遍发生使人们高度关注通过干预措施提高耐热性的可能性。然而,如果高耐热性与适应性权衡相关联,而这种权衡可能在其他方面对珊瑚不利,那么对耐热恢复力形成更全面的认识可能会有所助益。特别是,一个物种对热应激的整体恢复力可能是耐热性和从热应激中恢复能力的共同产物。在此,我们调查了帕劳单个珊瑚群落的耐热性和恢复情况。我们根据实验性热应激导致显著色素沉着丧失所需的天数(4 - 9天),将珊瑚分为低、中、高耐热性类别。之后,我们将珊瑚重新放置在一个礁坪上,进行为期6个月的共同花园恢复实验,监测叶绿素、死亡率和骨骼生长情况。耐热性与早期恢复(0 - 1个月)期间的死亡率呈负相关,但与后期恢复(4 - 6个月)期间的死亡率无关,并且热应激珊瑚在白化后1个月时叶绿素浓度有所恢复。然而,到恢复4个月时,中等耐热性珊瑚的骨骼生长明显大于高耐热性珊瑚。在观察到的恢复期内,高耐热性和低耐热性珊瑚平均未表现出骨骼生长。这些数据表明,珊瑚耐热性和恢复之间可能存在复杂的权衡,并凸显了将恢复力的多个方面纳入未来珊瑚礁管理计划的重要性。