Ocean Chemistry and Ecosystems Division, NOAA Atlantic Oceanographic and Meteorological Laboratory, 4301 Rickenbacker Causeway, Miami, FL, 33149, USA.
Rosenstiel School of Marine and Atmospheric Science, Cooperative Institute for Marine and Atmospheric Studies, University of Miami, 4600 Rickenbacker Causeway, Miami, FL, 33149, USA.
Sci Rep. 2023 Jan 5;13(1):258. doi: 10.1038/s41598-022-26930-4.
For reef framework to persist, calcium carbonate production by corals and other calcifiers needs to outpace loss due to physical, chemical, and biological erosion. This balance is both delicate and dynamic and is currently threatened by the effects of ocean warming and acidification. Although the protection and recovery of ecosystem functions are at the center of most restoration and conservation programs, decision makers are limited by the lack of predictive tools to forecast habitat persistence under different emission scenarios. To address this, we developed a modelling approach, based on carbonate budgets, that ties species-specific responses to site-specific global change using the latest generation of climate models projections (CMIP6). We applied this model to Cheeca Rocks, an outlier in the Florida Keys in terms of high coral cover, and explored the outcomes of restoration targets scheduled in the coming 20 years at this site by the Mission: Iconic Reefs restoration initiative. Additionally, we examined the potential effects of coral thermal adaptation by increasing the bleaching threshold by 0.25, 0.5, 1 and 2˚C. Regardless of coral adaptative capacity or restoration, net carbonate production at Cheeca Rocks declines heavily once the threshold for the onset of annual severe bleaching is reached. The switch from net accretion to net erosion, however, is significantly delayed by mitigation and adaptation. The maintenance of framework accretion until 2100 and beyond is possible under a decreased emission scenario coupled with thermal adaptation above 0.5˚C. Although restoration initiatives increase reef accretion estimates, Cheeca Rocks will only be able to keep pace with future sea-level rise in a world where anthropogenic CO emissions are reduced. Present results, however, attest to the potential of restoration interventions combined with increases in coral thermal tolerance to delay the onset of mass bleaching mortalities, possibly in time for a low-carbon economy to be implemented and complementary mitigation measures to become effective.
为了使珊瑚礁结构得以持续存在，珊瑚和其他造礁生物的碳酸钙产量必须超过因物理、化学和生物侵蚀而造成的损失。这种平衡既微妙又动态，目前正受到海洋变暖酸化影响的威胁。尽管保护和恢复生态系统功能是大多数恢复和保护计划的核心，但决策者受到缺乏预测工具的限制，无法根据不同的排放情景预测栖息地的持续情况。为了解决这个问题，我们开发了一种基于碳酸盐预算的建模方法，该方法利用最新一代气候模型预测结果（CMIP6），将特定物种对特定地点的全球变化的反应联系起来。我们将该模型应用于 Cheeca Rocks，这是佛罗里达群岛中珊瑚覆盖率较高的一个异常点，并探讨了 Mission:Iconic Reefs 恢复计划在未来 20 年内该地点的恢复目标的结果。此外，我们还通过将白化阈值提高 0.25、0.5、1 和 2°C，研究了珊瑚热适应的潜在影响。无论珊瑚的适应能力或恢复能力如何，一旦达到年度严重白化的起始阈值，Cheeca Rocks 的净碳酸盐产量就会大幅下降。然而，通过缓解和适应，从净积累到净侵蚀的转变会显著延迟。在排放减少的情况下，加上高于 0.5°C 的热适应，在 2100 年及以后维持框架积累是可能的。尽管恢复计划增加了珊瑚礁的积累估计，但如果人类 CO 排放量减少，Cheeca Rocks 只能在未来的海平面上升中保持同步。然而，目前的结果证明了恢复干预措施与珊瑚热耐受性提高相结合的潜力，这种潜力可以延迟大规模白化死亡的发生，以便有时间实施低碳经济并使补充缓解措施生效。
