Collaborative Research: Tipping points in coral reefs and their associated microbiomes: interactive effects of herbivory, nutrient enrichment, and temperature

合作研究：珊瑚礁及其相关微生物组的临界点：食草、营养富集和温度的相互作用

• 批准号: 2023701
• 负责人: Deron Burkepile
• 金额: $ 75.54万
• 依托单位: University of California-Santa Barbara
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-08-15 至 2025-07-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2023701&HistoricalAwards=false
• 关键词: Collaborative; Research; Tipping; points; coral; Collaborative; Research; Tipping; points; coral

Coral reefs are some of the most diverse, yet most imperiled, ecosystems on the planet. Global change has driven the decline of corals worldwide with many reefs now lacking corals and being overrun by macroalgae. This research examines the impacts of several factors of thermal stress, overfishing of important herbivorous fishes, and nutrient pollution on the health of corals and their ability to recover after large coral-killing disturbances. Importantly, the investigators address the impacts of global change on the coral microbiome, the microbes that associate with corals and impact coral health. The overarching hypothesis is that factors such as overfishing and nutrient pollution impact coral health via impacts to their microbes. This 6-year experiment on the coral reefs of Mo’orea, French Polynesia to examines what levels of herbivory, mostly by parrotfishes and surgeonfishes, are needed to provide resistance and resilience of corals and their microbiomes when reefs are exposed to elevated nutrients and ocean temperatures. Notably, the team tests how local stressors (overfishing, nutrient pollution) potentially interact with global stressors (climate change and rising ocean temperatures) to impact coral reef health. This research may yield insight into how to manage local factors (reducing fishing, mitigating nutrient pollution) to help corals survive the global stress of climate change. The field experiment provides a realistic platform to test questions about how local management of fisheries can alter reef health and provides data about the recoverability of reefs should new water quality management be put into place. This interdisciplinary work trains a new generation of both marine ecologists and microbiologists, including one postdoctoral researcher, two graduate students, as well as numerous undergraduates. The main international outreach effort is to map the microbiome of the island of Mo’orea. Mo’orea is approximately 130 square-kilometers in area and has five major watersheds that transport sediment and nutrients to the nearshore coral reef ecosystems. Thus poor stewardship of these watersheds likely contributes to the local phase shifts currently occurring in several areas of the lagoon. Therefore the team has engaged the local community to help collect microbiome samples from 50 terrestrial, 50 stream, 25 coastal sites, and 25 offshore sites around the island. The sampling effort is generating an island-wide map of the microbial communities associated with the soils, streams, and coastal waters that can be linked to adjacent coral reef health - The Moorea Microbiome! As part of this outreach effort, the team also collaborates with filmmakers to make a trilingual (English, French, and Tahitian) film about the project to serve as local engagement and teaching tool to help educate school groups and different stakeholders about both the seen and unseen connections between land and sea on their island. On the island of Mo’orea, French Polynesia, coral communities have exhibited strikingly different trajectories, with some reefs recovering from disturbances and others undergoing protracted coral decline, accompanied by an increase in macroalgae. This diversity in coral community dynamics makes Mo’orea an excellent model system for testing why some reefs are resilient and return to abundant coral while others are not and undergo persistent phase shifts to macroalgal dominance. This 6-year experiment will measure the dynamics of benthic communities, coral demography, and the coral microbiome across seasonal change in ocean temperature, allowing the team to (1) link changes in coral microbiomes (e.g., a rise in pathogenic bacteria) to the trajectories of coral decline or recovery and (2) link nutrients, herbivory, and temperature to phase shifts in both benthic communities and coral microbiomes. Importantly, the team is testing the resistance of phase shifts of benthic communities and coral microbiomes by measuring their changes after removing the nutrient enrichment treatment at the end of year 3 and tracking recovery of the system for 3 more years. Thus, this project begins to answer whether reef and microbial community phase shifts can be easily reversed once they occur. Many studies have focused on the factors that disassemble coral reef communities, but this is the first to examine how reef communities can be reassembled from the microbiome upwards.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

珊瑚礁是地球上生态系统最为差异，但最危险的。全球变化驱动了全球珊瑚的下降，现在许多珊瑚礁缺乏珊瑚，并且被大藻类淹没。这项研究检查了热应激的几个因素，重要的草食性鱼类过度捕获以及对珊瑚健康的养分污染的影响，以及在大型杀害珊瑚的灾难后恢复的能力。重要的是，研究人员解决了全球变化对珊瑚微生物组的影响，珊瑚微生物组是与珊瑚和影响珊瑚健康相关的微生物。总体假设是，诸如过度捕获和养分污染之类的因素通过对微生物的影响影响珊瑚健康。这项为期6年的法国波利尼西亚莫阿里亚（Mo'orea）珊瑚礁的实验需要检查哪些水平的草食性（主要是鹦鹉鱼和外科医生），以提供珊瑚及其微生物的抵抗力和弹性时，当珊瑚礁暴露于较高的营养成分和海洋温度时。值得注意的是，该团队测试了当地压力源（过度捕捞，营养污染）如何与全球压力（气候变化和海洋温度升高）相互作用，以影响珊瑚礁的健康。这项研究可能会洞悉如何管理当地因素（减少捕鱼，减轻营养污染），以帮助珊瑚在气候变化的全球压力中生存。现场实验提供了一个现实的平台，可以测试有关渔业的地方管理如何改变礁石健康的问题，并提供有关珊瑚礁恢复新水质管理的数据。这项跨学科的工作训练了新一代海洋生态学家和微生物学家，其中包括一名博士后研究员，两名研究生以及众多的本科生。国际主要的宣传工作是绘制Mo'orea岛的微生物组。 Mo’orea在地区约130平方公里，有五个主要的流域，可将沉积物和养分运送到近岸的珊瑚礁生态系统。这些流域的糟糕管理可能会导致目前在泻湖几个地区发生的当地相位变化。因此，该团队已与当地社区订婚，以帮助收集从50个地面，50个溪流，25个沿海地区和25个海上景点的微生物组样品。抽样工作正在生成与土壤，溪流和沿海水域相关的微生物群落的范围地图，该群落可以与邻近的珊瑚礁健康 - 摩尔菌微生物组联系起来！作为这项宣传工作的一部分，该团队还与电影制片人合作制作了一部关于该项目的三语（英语，法语和大溪地）电影，旨在作为当地参与和教学工具，以帮助教育学校团体和不同的利益相关者，了解岛上陆地和海洋之间所见和看不见的联系。在法属波利尼西亚的莫阿（Mo’orea）岛上，珊瑚社区暴露了截然不同的轨迹，其中一些礁石从灾难中恢复过来，而其他珊瑚礁则持续了持久的珊瑚下降，并伴随着大巨藻的增加。珊瑚社区动态中的这种多样性使Mo'orea成为测试为什么有些珊瑚礁具有抵抗力并恢复丰富的珊瑚的出色模型系统，而另一些珊瑚则没有，并且经历了持续的相位转移到大藻类的优势。这个为期6年的实验将衡量底栖群落，珊瑚人群和海洋温度季节性变化的珊瑚微生物组的动态，使团队（1）将珊瑚微生物组的变化（例如，致病细菌的升高）与珊瑚下降或恢复的轨迹以及（2）连接营养和库型，培训和温度相关，并将其连接起来。重要的是，该团队正在通过测量底栖群落和珊瑚微生物组的相位偏移的抵抗力，通过在第3年底去除营养富集处理后测量其变化，并在3年​​结束3年内跟踪系统的恢复。那就开始回答珊瑚礁和微生物社区阶段是否在发生后很容易逆转。许多研究都集中在拆卸珊瑚礁社区的因素上，但这是第一个研究如何从微生物组中重新组装珊瑚礁社区的奖项。这项奖项反映了NSF的法定任务，并通过使用基金会的知识分子和更广泛的影响审查审查标准来通过评估来诚实地通过评估来诚实地支持。