Collaborative Research: US GEOTRACES Pacific Section - Measurement of the organic complexation of dissolved iron, copper and cobalt, and total dissolved cobalt

溶解的铁（Fe）、铜（Cu）和钴（Co）是浮游植物生长的必需元素，它们反过来影响海洋碳循环；然而，尽管这一重要作用，这些生物活性元素的循环、分布和生物利用度仍然知之甚少。例如，强有机配体影响生物利用度和溶解度，但不清楚在不同条件下整个水柱的相互作用如何变化。认识到对这些数据的需求，来自百慕大海洋科学研究所、伍兹霍尔海洋研究所和斯克里普斯海洋研究所的研究人员将在2013年GEOTRACES巡航期间测量溶解的Fe、Cu和Co的有机络合以及总溶解Co浓度，该巡航将横断面秘鲁沿海上升流区、强氧最小带、东太平洋上升热液柱和塔希提岛附近的少营养水域。这项研究将产生一个关于这些生物活性元素在整个水柱中形成的重要数据集，这将有助于评估溶解的Fe， Cu和Co分布与配体浓度梯度之间的关系，并可能揭示这个动态海洋学区域的大化学梯度。关于溶解的Co浓度，这些测量应该提供关于该元素的海洋生物地球化学的新见解，特别是关于氧最低带和热液羽流。在更广泛的影响方面，为了推广工作，研究人员计划通过网络向公众传播他们的工作成果，在百慕大海洋科学研究所（BIOS）的参观期间，在每年的BIOS海洋科学服务日开放日，以及通过与海洋科学教育卓越中心合作制作的五部分网络研讨会系列-缅因州大学海洋系统和课堂课程。伍兹霍尔海洋研究所的一名研究生和斯克里普斯海洋学研究所的一名研究生将作为该项目的一部分接受培训和支持。

Dissolved iron (Fe), copper (Cu), and cobalt (Co) are essential elements for phytoplankton growth which in turn influences the marine carbon cycle; however, despite this important role, the cycling, distribution, and bioavailability of these bioactive elements remains poorly understood. For example, strong organic ligands influence bioavailability and solubility, but it is unclear how interactions change throughout the water column under variable conditions. Recognizing a need for this data, researchers from the Bermuda Institute of Ocean Sciences, Woods Hole Oceanographic Institution, and Scripps Institute of Oceanography will measure the organic complexation of dissolved Fe, Cu, and Co as well as total dissolved Co concentrations during the 2013 GEOTRACES cruise which will transect the coastal upwelling zone off Peru, an intense oxygen minimum zone, the East Pacific Rise hydrothermal plume, and the oligotrophic waters near Tahiti. This study will result in a significant dataset on the speciation of these bioactive elements throughout the water column which will help assess the relationships between dissolved Fe, Cu, and Co distributions and ligand concentration gradients and will likely reveal large chemical gradients over this dynamic oceanographic region. As regards dissolved Co concentrations, these measurements should provide new insights on the marine biogeochemistry of the element, especially in relation to oxygen minimum zones and hydrothermal plumes. In terms of the broader impacts, for the outreach efforts, the researchers plan to disseminate results from their work to the public via the web, during tours at the Bermuda Institute of Ocean Sciences (BIOS), and at the annual BIOS Marine Science Service Day open house, as well as through a five-part webinar series produced in collaboration with the Center for Ocean Sciences Education Excellence-Ocean Systems at the University of Maine and classroom curricula. One graduate student from Woods Hole Oceanographic Institution and one graduate student from Scripps Institute of Oceanography would be trained and supported as part of this project.