Collaborative Research: Physical Mechanisms Driving Food Web Focusing in Antarctic Biological Hotspots

海底峡谷作为海洋生物热点发挥着不成比例的重要作用，对于我们了解许多沿海生态系统至关重要。尽管气候变化很大，但南极半岛沿着与南极洲有关的生物热点已经持续了数千年。Palmer Deep峡谷是南极半岛西部沿着一个代表性热点，对该峡谷的海流观测表明，表层浮游植物水华以约1-2天的尺度进入和离开当地热点。这种居住时间与流行的观点相冲突，即峡谷相关的热点主要是由浮游植物维持的，这些浮游植物通过富含营养物质的深层沃茨的上涌而与这些特征相关联地在当地生长，这些营养物质为浮游植物的生长提供燃料。相反，这意味着水平海洋环流可能比通过其物理集中效应的局部上升流对维持这些生物热点更重要。该项目旨在更好地解决在南极半岛西部沿着峡谷形成和维持生物活动集中区的因素，并为海洋哺乳动物和鸟类创造当地觅食区。该项目的重点是分析维持这些生物热点的海洋运输和浓缩机制，将海洋学与浮游植物和磷虾联系起来，通过食物网与居民捕食者之一企鹅联系起来。此外，该研究将通过将教师及其学生与科学团队完全整合，与来自为代表性不足和服务不足的学生提供服务的学区的教师进行合作。学生将在与项目研究人员相同的时间内使用相同的数据进行自己的研究。揭示维持这些已知热点的基本机制将大大推进我们对海底峡谷和持续的企鹅种群热点之间在生态时间内观察到的联系的理解，并为南极热点的功能提供一个新的模型。 为了了解支持南极西部半岛（WAP）沿着持续热点的物理机制，该项目将整合一个建模和实地项目，该项目将针对负责将浮游植物和磷虾生物量运输和集中到已知企鹅觅食地点的过程。在帕尔默深峡谷，一个代表性的热点，该小组将部署一个高频雷达（HFR）沿海表面电流测绘网络，独特的装备，以确定漩涡和锋区集中浮游植物和磷虾。该实地方案以HFR确定的表面特征为中心，将包括：（一）协调一队滑翔机，以调查水文地理、叶绿素荧光、光学后向散射和目标会聚特征尺度上的主动声学;（二）用GPS连接的卫星遥测和时间深度记录器精确跟踪企鹅; ㈢每周进行一次小船调查，以适应性地瞄准和跟踪会聚特征，以测量浮游植物、磷虾和水文地理。一个高分辨率的物理模型将概括我们的现场测量其他已知的热点沿着WAP通过模拟，并确定哪些物理机制导致这些热点的维护。该项目还将通过一项教育计划，让教育工作者、学生和公众参与南极研究和数据分析，促进教学，扩大代表性不足群体的参与。这种参与包括专业发展研讨会，现场连接到公众和教室，学生研究座谈会，并计划评估。 综合研究和参与将促进我们对区域运输途径和当地深度依赖的集中物理机制在维持这些生物热点中发挥的作用的理解。该奖项反映了NSF的法定使命，并被认为值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估来支持。

Undersea canyons play disproportionately important roles as oceanic biological hotspots and are critical for our understanding of many coastal ecosystems. Canyon-associated biological hotspots have persisted for thousands of years Along the Western Antarctic Peninsula, despite significant climate variability. Observations of currents over Palmer Deep canyon, a representative hotspot along the Western Antarctic Peninsula, indicate that surface phytoplankton blooms enter and exit the local hotspot on scales of ~1-2 days. This time of residence is in conflict with the prevailing idea that canyon associated hotspots are primarily maintained by phytoplankton that are locally grown in association with these features by the upwelling of deep waters rich with nutrients that fuel the phytoplankton growth. Instead, the implication is that horizontal ocean circulation is likely more important to maintaining these biological hotspots than local upwelling through its physical concentrating effects. This project seeks to better resolve the factors that create and maintain focused areas of biological activity at canyons along the Western Antarctic Peninsula and create local foraging areas for marine mammals and birds. The project focus is in the analysis of the ocean transport and concentration mechanisms that sustain these biological hotspots, connecting oceanography to phytoplankton and krill, up through the food web to one of the resident predators, penguins. In addition, the research will engage with teachers from school districts serving underrepresented and underserved students by integrating the instructors and their students completely with the science team. Students will conduct their own research with the same data over the same time as researchers on the project. Revealing the fundamental mechanisms that sustain these known hotspots will significantly advance our understanding of the observed connection between submarine canyons and persistent penguin population hotspots over ecological time, and provide a new model for how Antarctic hotspots function. To understand the physical mechanisms that support persistent hotspots along the Western Antarctic Peninsula (WAP), this project will integrate a modeling and field program that will target the processes responsible for transporting and concentrating phytoplankton and krill biomass to known penguin foraging locations. Within the Palmer Deep canyon, a representative hotspot, the team will deploy a High Frequency Radar (HFR) coastal surface current mapping network, uniquely equipped to identify the eddies and frontal regions that concentrate phytoplankton and krill. The field program, centered on surface features identified by the HFR, will include (i) a coordinated fleet of gliders to survey hydrography, chlorophyll fluorescence, optical backscatter, and active acoustics at the scale of the targeted convergent features; (ii) precise penguin tracking with GPS-linked satellite telemetry and time-depth recorders (TDRs); (iii) and weekly small boat surveys that adaptively target and track convergent features to measure phytoplankton, krill, and hydrography. A high resolution physical model will generalize our field measurements to other known hotspots along the WAP through simulation and determine which physical mechanisms lead to the maintenance of these hotspots. The project will also engage educators, students, and members of the general public in Antarctic research and data analysis with an education program that will advance teaching and learning as well as broadening participation of under-represented groups. This engagement includes professional development workshops, live connections to the public and classrooms, student research symposia, and program evaluation. Together the integrated research and engagement will advance our understanding of the role regional transport pathways and local depth dependent concentrating physical mechanisms play in sustaining these biological hotspots.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.