Collaborative Research: Understanding the impact of warming on the structure and function of marine communities

气温上升正在影响世界各地的海洋生态系统，而且预计变暖的速度还会加快。西北大西洋大陆架的生态系统，包括缅因湾和中大西洋湾，经历了历史记录中最快的十年和30年变暖速度，这些强烈的变暖趋势在2012年、2016年和2018年被海洋热浪打断。大多数关于气候对海洋影响的研究都集中在温度上升如何影响单个物种上。该项目侧重于气候变暖对整个生态系统的影响，包括短期事件和长期趋势。它利用该地区最近的变暖和持续采样的历史，将较冷的缅因湾与较温暖的中大西洋湾的浮游生物和鱼类群落的特性进行对比。通过统计分析、基于尺度的模型和食物网模型，本项目评估了温度对生物过程、群落特征和新兴生态系统特性的直接和间接影响。本研究描述了浮游生物和鱼类群落的组成和特征，并比较了生态系统在时空上的变化。它还将温度对新陈代谢和生长的直接影响与温度通过海洋学变化产生的间接影响分离开来。了解海洋生态系统如何对变暖做出反应，对于在气候变化中成功管理这些生态系统至关重要。项目小组积极致力于将知识转化为区域和国家一级的渔业管理。该项目还通过扩大缅因湾研究所LabVenture项目的生态系统建模活动来教育下一代公民和科学家，该项目每年为约10,000名缅因中学生提供服务。关于建模的在线课程正在开发中，这是《下一代科学标准》中许多教师认为具有挑战性的主题领域。该项目还资助了一名博士后研究员和一名研究生，并为石溪大学鼓励女性参与科学的项目做出了贡献。温度影响新陈代谢和生长，在温暖的条件下，大多数物种生长得更快，但成熟得更早，体型也更小。该项目描述了温度对鱼类生长模式的直接影响，并将这些知识纳入鱼类群落的基于特征的大小光谱模型。该模型量化了温度和浮游动物组成的变化如何转化为鱼类群落大小结构的变化。变暖导致物种向极地移动，使得传统上较冷的生态系统变得与过去较暖的生态系统相似。该项目使用动态食物网模型来综合物种组成的变化如何改变缅因湾和中大西洋湾生态系统的能量流。它还量化了这些群落的稳定性及其对海洋热浪等扰动的适应能力，预期逐渐变暖会导致群落变得更加多样化，从而更加稳定，而突然变暖可能会产生相反的效果。这两个分量对比了温暖的大西洋中部和凉爽的缅因湾的生态系统特性，以及过去和最近非常温暖条件下的生态系统特性。这种比较方法还将变暖对生物体的直接影响与垂直分层的间接影响分开。特别是，将最近的热分层时期与1990年代（当时盐度降低导致了突然的多营养层群落转移）进行比较，可以将温度的直接影响与其通过水文的影响分离开来。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Rising temperatures are impacting marine ecosystems around the world, and the rate of warming is expected to accelerate. The ecosystems in the northwest Atlantic Shelf, including in the Gulf of Maine and Mid-Atlantic Bight, have experienced some of the fastest decadal and 30 year warming rates in the historical record, and these strong warming trends were punctuated by marine heatwaves in 2012, 2016, and 2018. Most studies of climate impacts in the ocean have focused on how rising temperatures affect individual species. This project focuses on the impact of warming, both short-term events and long-term trends, on the entire ecosystem. It leverages the region's recent warming and history of consistent sampling to contrast the properties of the plankton and fish communities in the colder Gulf of Maine with the warmer Mid-Atlantic Bight. Through statistical analyses, size-based modeling, and food web modeling, this project evaluates direct and indirect influences of temperature on biological processes, community characteristics, and emergent ecosystem properties. This study characterizes composition and features of the plankton and fish communities and compares ecosystem changes across space and through time. It also isolates the direct influence of temperature on metabolism and growth from the indirect influence of temperature through changes in the oceanography. An understanding how marine ecosystems respond to warming is essential to successfully manage these ecosystems in a changing climate. The project team is actively engaged in translating knowledge into fisheries management at a regional and national level. This project also educates the next generation of citizens and scientists by expanding the ecosystem modeling activity in the Gulf of Maine Research Institute's LabVenture program, which serves ~10,000 Maine middle school students each year. An online curriculum on modeling, a topic area in the Next Generation Science Standards that many teachers find challenging is under development. The project also supports a postdoctoral researcher and a graduate student and contributes to Stony Brook University's program to encourage participation of women in the sciences.Temperature affects metabolism and growth, with most species growing faster but maturing earlier and at a smaller size in warmer conditions. This project characterizes the direct influence of temperature on fish growth patterns and incorporates this knowledge into a trait-based, size-spectrum model of a fish community. This model quantifies how changes in temperature and zooplankton composition translate into changes in size structure of the fish community. Warming causes poleward movement of species such that traditionally cooler ecosystems come to resemble warmer ecosystems of the past. This project uses a dynamic food-web model to synthesize how changes in species composition have altered the flow of energy in Gulf of Maine and Mid-Atlantic Bight ecosystems. It also quantifies the stability of these communities and their resilience to perturbations like marine heatwaves, with the expectation that gradual warming causes communities to become more diverse and thus more stable, while abrupt warming may have the opposite effect. Both components contrast the ecosystem properties in the warmer mid Atlantic with those in the cooler Gulf of Maine as well as those properties in the past with those under the recent very warm conditions. The comparative approach also untangles the direct impact of warming on organisms from the indirect effects from vertical stratification. In particular, comparing the recent thermally stratified period with the 1990s, when reduced salinity led to an abrupt, multi trophic-level community shift, make it possible to isolate the direct effects of temperature from its influence through hydrography.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.