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，进而影响海洋碳循环；然而，尽管具有如此重要的作用，但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，但尚不清楚在不同条件下整个水柱中的相互作用如何变化。认识到对这些数据的需求，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 航行期间测量溶解的铁、铜和钴的有机络合以及溶解的总钴浓度，该航行将横穿秘鲁沿海上升流区、强氧最低区、东太平洋海隆热液羽流和塔希提岛附近的贫营养水域。 这项研究将产生关于整个水体中这些生物活性元素形态的重要数据集，这将有助于评估溶解的铁、铜和钴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区域的大化学梯度。 至于溶解的钴浓度，这些测量应该为该元素的海洋生物地球化学提供新的见解，特别是与氧最低区和热液羽流相关的知识。就更广泛的影响而言，为了推广工作，研究人员计划通过网络、百慕大海洋科学研究所（BIOS）参观期间、年度 BIOS 海洋科学服务日开放日以及通过与缅因大学海洋科学教育卓越中心和课堂课程合作举办的由五部分组成的网络研讨会系列向公众传播他们的工作成果。 作为该项目的一部分，伍兹霍尔海洋研究所的一名研究生和斯克里普斯海洋研究所的一名研究生将接受培训和支持。

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.