RAPID collaborative proposal: Will corals recover from bleaching under ocean acidification conditions?

在经历了20世纪40年代以来第二个最热的月份之后，夏威夷主要岛屿附近的水温在2014年10月达到了30摄氏度。比正常温度高出2摄氏度的结果是整个夏威夷群岛发生了严重的漂白事件。在卡内奥赫湾，75%的优势珊瑚物种被漂白。漂白是一种压力反应，珊瑚失去了共生的藻类，变白了。长时间的漂白会导致疾病，减少珊瑚的生长和繁殖，甚至死亡。此外，大气中二氧化碳水平的上升导致海洋变得更加酸性，可能不太适合珊瑚礁。到本世纪末，海水的酸性预计将是今天的两倍。夏威夷目前的漂白事件提供了一个难得的机会，可以测试珊瑚在预计本世纪末的酸性海洋条件下恢复的能力。这项研究比较了漂白珊瑚在正常海水和暴露在更酸性海水中的回收率。结果将告知哪些物种或珊瑚礁区域对全球变化条件更具弹性，从而更好地成为保护目标。这一成果将与帕帕哈瑙莫库凯亚海洋国家纪念碑和世界遗产的管理特别相关。它还将为预测未来珊瑚礁持久性的模型提供关键数据输入。在教育方面，该研究将为学生和博士后研究人员提供一个动态的学习和培训环境。少数族裔学生将被招募并接受海洋科学方面的培训，为他们在STEM学科中提供极好的职业选择。结果将通过出版物、课堂访问、公众宣传和在线媒体广泛传播。珊瑚礁是地球上最多样化的生态系统之一，估计居住着25%的海洋物种。大规模的珊瑚漂白对珊瑚礁栖息地的完整性构成了严重威胁，预计在未来的气候模型情景下，珊瑚礁将成为死亡的主要来源。尽管之前关于从漂白中恢复珊瑚的工作为这一项目奠定了基础，但气候变化和海洋酸化将如何影响从漂白中恢复仍有待观察。该项目利用了HI的卡内奥赫湾和怀马纳罗湾之间基线温度和海水酸度条件的自然差异。这两个地点都受到了大规模漂白事件的影响。这项研究将测试在正常海水中漂白的珊瑚与暴露在更酸性海水中的漂白珊瑚的恢复率。将讨论三个问题：1)海洋酸化会减慢漂白的恢复速度吗？2)浮游动物摄食是否将漂白的影响降至最低？3)适应更温暖、更酸性条件的珊瑚(卡内奥赫湾)是否比目前平均海洋条件(威马纳罗湾)的珊瑚恢复得更快？该项目整合了生态学、生理学、进化论和基因组学等学科的技术。这项研究将有助于确定未来更有可能在白化事件中幸存下来的有弹性的珊瑚物种或种群的特征。

Following the second hottest month on record since the 1940s, water temperatures near the main Hawaiian Islands reached 30 °C in October 2014. The result of this 2 °C increase above normal temperatures has been a severe bleaching event across the Hawaiian Archipelago. In Kaneohe Bay, 75% of the dominant coral species are bleached. Bleaching is a stress response whereby corals lose their symbiotic algae and turn white. Prolonged bleaching can lead to disease, decreases in coral growth and reproduction, and even death. In addition, rising atmospheric levels of carbon dioxide cause the oceans to become more acidic and potentially less hospitable to coral reefs. By the end of this century, seawater is predicted to be twice as acidic as it is today. The current bleaching event in Hawaii provides a rare opportunity to test the ability of corals to recover under the acidic ocean conditions expected by the end of this century. This research compares the recovery rate of bleached corals in normal seawater to those exposed to more acidic seawater. The results will inform which species or reef regions are more resilient to global change conditions and thus better targets for protection. The results will be particularly relevant to management of the Papahanaumokuakea Marine National Monument and World Heritage site. It will also provide critical data input for models that project the persistence of reefs in the future. Educationally, the research will provide a dynamic learning and training environment for students and a post-doctoral researcher. Minority students will be recruited and trained in marine science providing them with excellent career options in STEM disciplines. Results will be broadly disseminated through publications, classroom visits, public outreach and online media. Coral reefs are among the most diverse ecosystems on the planet, housing an estimated 25% of marine species. Massive coral bleaching poses a substantial threat to the integrity of coral reef habitats, and is predicted to be the major source of mortality for reefs under future climate model scenarios. Although previous work on the recovery of corals from bleaching sets the groundwork for this project, it remains to be seen how recovery from bleaching will be impacted by climate change and ocean acidification. This project takes advantage of the natural difference in baseline temperature and seawater acidity conditions between Kaneohe Bay and Waimanalo Bay, HI. Both these sites are impacted by the massive bleaching event. This research will test the recovery rate of bleached corals in normal seawater to that of bleached corals exposed to more acidic seawater. Three questions will be addressed: 1) Will ocean acidification slow rates of recovery from bleaching?; 2) Does zooplankton feeding minimize the impact of bleaching?; and 3) Do corals acclimated to warmer, more acidic conditions (Kaneohe Bay) recover more quickly than corals at present day mean oceanic conditions (Waimanalo Bay)? The project integrates techniques across the disciplines of ecology, physiology, evolution, and genomics. The research will help to identify characteristics of resilient coral species or populations that are more likely to survive bleaching events in the future.