Collaborative Research: Net Carbon Transport and Reaction in the bottom Boundary Layer of an Upwelling Margin

上升海岸边缘是碳循环、海气交换和氧化还原化学强烈的区域，其中海底、海洋内部和海气界面紧密耦合。在这项研究中，来自俄勒冈州立大学、华盛顿大学、芝加哥大学、普林斯顿大学和哥伦比亚大学的多学科团队将对底部边界层内的输送和生物地球化学反应速率、沿海和开阔海洋、海面和大气以及水柱和海底之间的边界交换进行协调研究。他们假设，在这些环境中的净碳通量是由底部边界层中物理输送和化学反应的并列控制的。他们将解决以下问题：群落碳净生产量中有多少最终被隔离在海洋内部，这是如何发生的；负责高净群落生产量的大型快速生长的沿海硅藻如何满足它们对铁的需求，以及有多少可移动的铁和甲烷到达照明深度和/或海面和向大气排放的气体。这些目标将通过俄勒冈州海岸外的一个实地计划来实现，该计划将包括以下内容：(1)对水柱中的温度、盐度、速度、碳(无机PCO2和TCO2，以及颗粒和溶解有机碳)、甲烷和铁的分布进行高分辨率调查；(2)故意在底部边界层释放多种示踪剂，以检查物理传输过程、光照历史和海-气气体交换；(3)利用沉积物和边界层之间的海底通量传输室进行直接测量；(4)利用孵化法和复合特异性标志物测定边界层中有机质、铁和甲烷的反应性。数据合成、碳预算和建模工作将整合所有现场数据，纳入反应和传输速率，并产生预测能力，可以将我们的结果扩展到其他上升流系统。在更广泛的影响中，这项研究将产生几项在地球科学中具有多学科应用的技术发展。来自五个机构的八名研究生将参与这个项目，要么获得硕士学位，要么为博士论文奠定基础。本科生将参加实验室和实地考察。外展活动包括记者和成人教育工作者参与探险，以及与俄勒冈州海洋科学和数学合作计划合作，该计划提供将海洋科学与现实生活问题联系起来的学习活动，并接触到服务不足的成人学习者群体。

ABSTRACTOCE - 0628629Upwelling coastal margins are regions of intense carbon cycling, air-sea gas exchange, and redox chemistry where the sea floor, ocean interior, and air-sea interface are closely coupled. In this research, a multidisciplinary team from Oregon State University, University of Washington, University of Chicago, Princeton University, and Columbia University will conduct a coordinated study of transport and biogeochemical reaction rates within the bottom boundary layer, and of exchanges across the boundaries between coastal and open ocean; the sea surface and atmosphere; and the water column and seafloor. They hypothesize that net carbon fluxes in these settings are governed by the juxtaposition of physical transport and chemical reaction in the bottom boundary layer. They will address questions such as how much of the net community carbon production is ultimately sequestered in the ocean interior and how does this happen, how do large, fast-growing coastal diatoms responsible for the high net community production meet their iron demands, and how much mobilized iron and methane reaches illuminated depths and/or the sea-surface and outgases to the atmosphere. These goals will be accomplished with a field program off the Oregon coast that will include the following: (1) high-resolution surveys of the distributions of temperature, salinity, velocity, carbon (inorganic pCO2 and TCO2, and particulate and dissolved organic carbon), methane, and iron in the water column; (2) deliberate multiple-tracer releases in the bottom boundary layer to examine physical transport processes, illumination history, and air-sea gas exchange; (3) direct measurement using benthic flux chambers of transport between the sediments and the boundary layer; (4) measurement of reactivity of organic matter, iron and methane in the boundary layer using incubations and compound specific markers. Data-synthesis, carbon-budgeting, and modeling efforts will integrate all the field data, incorporate reaction and transport rates, and generate predictive capabilities that can extend our results to other upwelling systems. Among the broader impacts, the research will produce several technological developments that will have multi-disciplinary applications in earth science. Eight graduate students from five institutions will participate in this project, producing either master's degrees or the foundations for doctoral dissertations. Undergraduate students will participate in the laboratory and fieldwork. Outreach activities include participation of reporters and adult educators on the expeditions, as well as working with the State of Oregon's Ocean Sciences and Math Collaborative program that provides learning activities linking ocean sciences with real life issues and reaches an underserved population of adult learners.