COLLABORATIVE RESEARCH: Influence of Temperature and Acidification on the Dynamics of Coral Co-Infection and Resistance

“这项奖励是根据2009年美国复苏和再投资法案（公法111-5）资助的。”珊瑚礁生态系统受到最近气温上升和预计海洋酸化加剧的高度威胁。虽然温度已被确定为某些珊瑚疾病爆发的驱动因素，但酸化对宿主免疫和病原体毒力的直接影响，或与温度协同作用的可能性，尚不清楚。天然珊瑚种群经常同时遭受多种病原体的感染，这些病原体也会影响宿主的免疫反应，但在缺乏经典适应性免疫的无脊椎动物系统中，共同感染动力学尚未得到研究。气候变化很可能影响单次感染和合并感染的结果。本项目将研究环境胁迫对海扇珊瑚（Gorgonia ventalina）与真菌病原体西多曲霉（Aspergillus sydowii）和原生寄生虫SPX共感染动态的影响。目标是确定多重感染、温度和酸化改变宿主抵抗力的机制，从而导致菌落内和菌落间疾病传播率的变化。该项目的目标是：-确定西多曲霉和SPX的发病率和共同感染频率，对这两种疾病进行详细的实地调查将检验共同感染是重要的假设，提供有关曲霉病驱动因素的宝贵信息，并将有助于确定新出现的海扇疾病的特征。-调查共同感染如何影响海扇易感性、抗性和宿主疾病动态。通过可操作的实验室接种实验，我们将检验单一感染增加对第二病原体易感性的假设。-检查温度升高和海洋酸化对病原体毒力的影响，对潜在宿主耐药性的影响，以及对单一和共同感染动力学的影响。酸化将增加病原体毒力和宿主敏感性的假设将在温度和pH控制的实验系统中进行测试。该系统还将允许探索温度和酸化对宿主免疫和共感染动力学的潜在协同效应。提出的工作的主要知识价值将是更好地理解气候变化如何介导非模式无脊椎动物的共同感染和免疫。虽然真菌病原体主要是机会性的，但迷路原生动物被认为是贝类的主要病原体。即使在贝类中，也很少有人知道涉及迷宫的共同感染，而这些原生生物在珊瑚中也完全没有被研究过。这项活动的广泛影响包括培训本科生、研究生和博士后研究人员，以及与当地（如伊萨卡科学中心）和国际教育推广项目（世界银行全球环境基金：GEF）的合作。此外，公众对珊瑚礁的迷恋可以作为提请人们关注全球气候危机的工具。调查人员的工作从主要的国内和国际媒体收到了大量的通知，这加强了康奈尔大学的科学传播努力。这种公共利益也使他们能够参与影响全球环境政策的政策讨论，例如在美国珊瑚礁工作组面前发言。调查人员通过世界银行的合作努力最近也达到了高潮，出版了《珊瑚疾病手册》和水下身份证，以协调国际珊瑚礁管理。该项目将进一步支持这些努力，以宣传继续支持海洋科学、气候研究和主动管理计划的必要性。

"This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5)."Coral reef ecosystems are highly endangered by recent increases in temperature and by projected increases in ocean acidification. Although temperature has been identified as a driver of some coral disease outbreaks, nothing is known about direct effects of acidification on host immunity and pathogen virulence, or the potential for synergism with temperature. Natural coral populations often suffer from simultaneous infection by multiple pathogens that can also influence host immune responses, but co-infection dynamics have not been investigated in invertebrate systems lacking classical adaptive immunity. Changing climate will very likely influence the outcome of single and co-infection. This project will investigate the influence of environmental stress on co-infection dynamics of the sea fan coral, Gorgonia ventalina, with a fungal pathogen, Aspergillus sydowii and a protist parasite, SPX. The goal is to identify the mechanisms through which multiple infections, temperature and acidification modify host resistance, leading to changes in within- and among-colony rates of disease spread. The Objectives of this project are to: -Identify incidence and co-infection frequency of Aspergillus sydowii and SPX Detailed field surveys of the two diseases will test the hypothesis that co-infection is significant, provide valuable information about drivers of aspergillosis, and will help to characterize an emerging new sea fan disease. -Investigate how co-infection influences sea fan susceptibility, resistance, and within host disease dynamics. Through manipulative lab inoculation experiments we will test the hypothesis that single infections increase susceptibility to a second pathogen. -Examine the effects of temperature increase and ocean acidification on pathogen virulence, on underlying host resistance, and on the dynamics of single and co-infections The hypotheses that acidification will increase pathogen virulence and host susceptibility will be tested in a temperature and pH controlled experimental system. This system will also allow the potential synergistic effects of temperature and acidification on host immunity and co-infection dynamics to be explored. The primary intellectual merit of the proposed work will be a greater understanding of how changing climate mediates co-infection and immunity in a non-model invertebrate. While fungal pathogens are primarily opportunistic, labyrinthulid protozoans are recognized as primary pathogens in shellfish. Even in shellfish, little is known about co-infections involving labyrinthulids, and these protists are entirely unstudied in corals. The Broader impacts of this activity include training of undergraduates, graduate students, and postdoctoral researchers, as well as collaborations with established local (e.g. Ithaca Sciencenter) and international educational outreach programs (World Bank Global Environmental Fund: GEF). In addition, the public's fascination with coral reefs can be used as a tool in drawing attention to the global climate crisis. The considerable notice the investigators work has received from major national and international media has bolstered Cornell's science communication efforts. This public interest has also allowed then to participate in policy discussions that will influence global environmental policies, such as speaking before the U.S. Coral Reef Task Force. The investigators collaborative efforts through the World Bank have also recently culminated in the publication of a Coral Disease Handbook and underwater ID cards that will coordinate international coral reef management. The project will further support these efforts to communicate the need for continued support of the marine sciences, climate studies, and proactive management programs.