Consequences of hypoxia on food web linkages in a pelagic marine ecosystem

智力价值低溶解氧(缺氧)是海洋生态系统中最明显、最普遍和最重要的干扰之一。然而，由于我们对生物对低氧的反应如何影响关键的生态系统过程的了解有限，我们对低氧对远洋食物网的生态影响的了解是不完整的。在中上层食物网中，中浮游动物及其捕食者的分布变化可能会影响捕食者-猎物的重叠，并决定能量沿食物网向上流动。同样，低氧可能会导致浮游动物群落组成向阻碍能量流向食浮游鱼类的物种转移。然而，物种和群落的补偿反应可能会抵消这些影响，维持营养耦合和维持高营养层物种的生产力。PI建议回答这样一个问题：“低氧是否影响从中游动物到中上层鱼类的能量流动？”他们通过一个嵌套的假设框架来处理这个问题，该框架考虑了两组交替负责改变或维持远洋生态系统能量流的过程。他们将在华盛顿州胡德运河进行研究。与大多数受缺氧影响的河口不同，胡德运河的缺氧区非常接近不受影响的地点。这使得进行比较研究在后勤上更容易，并减少了在比较相距遥远的地区时潜在混杂因素的数量。更好地理解低氧对海洋生态系统的影响将有助于基于生态系统的管理(EBM)在沿海和河口生态系统中的实际应用。循证医学的有效应用要求充分了解人类活动的影响，并使用指标跟踪生态影响。该项目将有助于满足这两方面的需求。PI将与联邦、州、部落和县的生物学家分享他们在地方和国家层面上的发现。为了增加对代表性不足群体的科学接触，私人投资机构还将通过暑期实习为美洲原住民青年提供参与实地收集和实验室处理的机会。PIS将与美国国家科学基金会资助的太平洋西北路易斯·斯托克斯少数民族参与联盟和胡德运河地区的部落合作，为潜在的海洋科学职业招募和指导学生。这个项目将支持几名本科生、两名博士生、一名博士后和两名职业生涯早期的科学家。

Intellectual MeritLow dissolved oxygen (hypoxia) is one of the most pronounced, pervasive, and significant disturbances in marine ecosystems. Yet, our understanding of the ecological impacts of hypoxia on pelagic food webs is incomplete because of our limited knowledge of how organism responses to hypoxia affect critical ecosystem processes. In pelagic food webs, distribution shifts of mesozooplankton and their predators may affect predator-prey overlap and dictate energy flow up food webs. Similarly, hypoxia may induce shifts in zooplankton community composition towards species that impede energy flow to planktivorous fish. However, compensatory responses by species and communities might negate these effects, maintaining trophic coupling and sustaining productivity of upper trophic level species. The PIs propose to answer the question "Does hypoxia affect energy flow from mesozooplankton to pelagic fish?" They approach this question with a nested framework of hypotheses that considers two sets of processes alternatively responsible for either changes or maintenance of pelagic ecosystem energy flows. They will conduct their study in the Hood Canal, WA. Unlike most hypoxia-impacted estuaries, hypoxic regions of Hood Canal are in close proximity to sites that are not affected. This makes it logistically easier to conduct a comparative study and reduces the number of potential confounding factors when comparing areas that are far apart.Broader ImpactsImproved understanding of how hypoxia impacts marine ecosystems will benefit the practical application of ecosystem-based management (EBM) in coastal and estuarine ecosystems. Effective application of EBM requires that the impacts of human activities are well understood and that ecological effects can be tracked using indicators. This project will contribute to both of these needs. The PIs will share their findings on local and national levels with Federal, State, Tribal, and County biologists. To increase exposure of science to underrepresented groups, the PIs also will provide Native American youth with opportunities to participate in field collections and laboratory processing through summer internships. The PIs will collaborate with the NSF-funded Pacific Northwest Louis Stokes Alliance for Minority Participation and tribes from the Hood Canal region to recruit and mentor students for potential careers in marine science. This project will support several undergraduate researchers, two Ph.D. students, a post-doc, and two early-career scientists.