LTER: Ecosystem controls and multiple stressors in a coastal upwelling system - CCE IV

沿海上升流区位于所有海洋盆地的东部边界，是海洋中生产力最高的生态系统之一。该奖项支持加州当前生态系统长期生态研究(CCE LTER)在一个主要的上升生物群中的站点。它利用了73年的加州合作海洋渔业调查(CalCOFI)计划，该计划提供了描述该系统中气候变异性和变化的基本信息。CCE LTER解决了两个最重要的问题：导致沿海远洋生态系统生态转变的机制是什么？变化的海洋气候、群落结构和生态系统动态之间的相互作用是什么？研究人员正致力于诊断生态系统变化的机制，并为预测未来条件以及这些条件可能如何影响包括大量鱼类、无脊椎动物、海洋哺乳动物和海鸟在内的关键海洋生物资源的管理开发一个量化框架。他们正在培养研究生和本科生，并为教师提供教育机会。与斯克里普斯海洋研究所白桦水族馆合作的公共项目和推广工作正在提高公众对气候对沿海远洋群落影响的认识和理解，并将公众与前沿海洋研究联系起来。该项目正在增加对以下三个相互关联的焦点的生态突变机制的理解：(1)调查海洋热浪及其对生物体和群落的综合压力；(2)阐明生态化学计量学和多个营养水平对源养分元素比例变化的响应；以及(3)分析由不同的生物体调节的自上而下的压力。它正在维持对五个核心LTER变量的多尺度测量，以及对海洋变暖、层化增加、酸化、脱氧和东北太平洋营养物质化学计量比变化的响应。研究人员正在使用多个空间尺度上的长期、空间分辨的时间序列来评估多个时间尺度上的群落变化，新的测量方法允许在更精细的分类水平上进行询问。他们正在进行现场多因素实验(温度、大量营养素、微量营养素、光照、放牧)，并结合基因组和转录组分析。这些将补充时间序列测量，为下一代生物地球化学模型提供信息，并测试与生态化学计量学和海洋热浪相关的假设。该团队还使用了一套成像技术、分子和形态方法以及主动和被动声学方法来量化整个营养层的生物的垂直结构和共生状态，并测试关于自上而下控制生态系统的假设。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Coastal upwelling regions are found along the eastern boundaries of all ocean basins and are some of the most productive ecosystems in the ocean. This award is supporting the California Current Ecosystem Long Term Ecological Research (CCE LTER) site in a major upwelling biome. It leverages the 73-year California Cooperative Oceanic Fisheries Investigations (CalCOFI) program which provides essential information characterizing climate variability and change in this system. The CCE LTER addresses two over-arching questions: What are the mechanisms leading to ecological transitions in a coastal pelagic ecosystem? And what is the interplay between changing ocean climate, community structure, and ecosystem dynamics? The investigators are working towards diagnosing mechanisms of ecosystem change and developing a quantitative framework for forecasting future conditions and how these might affect the management of key living marine resources, including numerous fishes, invertebrates, marine mammals, and seabirds. They are training graduate and undergraduate students, as well as providing educational opportunities for teachers. Public programs and outreach efforts in collaboration with the Birch Aquarium at Scripps Institution of Oceanography are increasing public awareness and understanding of climate effects on coastal pelagic communities and connecting the public to cutting-edge ocean research.This project is adding to understanding of the mechanisms underlying abrupt ecological transitions with three interrelated foci: (1) investigation of marine heatwaves and resultant multiple stressors on organisms and communities, (2) elucidation of ecological stoichiometry and the response of multiple trophic levels to altered elemental ratios of source nutrients, and (3) analysis of top-down pressures mediated by a diverse suite of organisms. It is sustaining multi-scale measurements of five core LTER variables and responses to ocean warming, increased stratification, acidification, deoxygenation, and altered nutrient stoichiometry in the Northeast Pacific. The investigators are using long-term, spatially-resolved time series at multiple spatial scales to evaluate community shifts at multiple temporal scales, with new measurements allowing interrogation at finer taxonomic levels. They are conducting in situ multi-factorial experiments (temperature, macronutrients, micronutrients, light, grazing) in combination with genomic and transcriptomic analyses. These will complement time series measurements, inform next-generation biogeochemical models, and test hypotheses related to ecological stoichiometry and marine heatwaves. The team is also using a suite of imaging techniques, molecular and morphological methods, and active and passive acoustic approaches to quantify vertical structure and cooccurrence of organisms across trophic levels and test hypotheses about top-down control of the ecosystem.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.