Collaborative Research: US GEOTRACES GP17-OCE: Shipboard Measurements of Dissolved Aluminum, Iron, and Manganese – Tracing Inputs to the South Pacific Gyre and Southern Ocean

合作研究：美国 GEOTRACES GP17-OCE：溶解铝、铁和锰的船上测量 — 追踪南太平洋环流和南大洋的输入

• 批准号: 2123623
• 负责人: Peter Sedwick
• 金额: $ 33.77万
• 依托单位: Old Dominion University Research Foundation
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-01 至 2024-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2123623&HistoricalAwards=false
• 关键词: Collaborative; Research; US; GEOTRACES; GP17

The goal of the international research program GEOTRACES is to understand the distributions of trace chemical elements and their isotopes in the oceans. The importance of trace elements in the ocean lies in their roles as essential micronutrients for marine phytoplankton (e.g., iron), as toxicants (e.g., lead), and as tracers of past and present oceanic processes (e.g., thorium). In this project, the dissolved concentrations of two micronutrient trace elements (iron and manganese) and a tracer of atmospheric dust deposition (aluminum) will be measured in seawater samples collected during a research cruise in the southeastern Pacific Ocean and adjacent Southern Ocean, in order to better understand the inputs of these micronutrients and their impact on biological processes in these regions. Chemical analyses will be performed at sea in near real-time, thus providing a first glimpse of data that will inform the cruise sampling strategy and the analyses performed by other investigators. The project involves two US laboratories, and will support the research of a graduate and undergraduate student. The U.S. GEOTRACES GP17-OCE expedition will focus on the distribution of trace elements and isotopes along a transect crossing the South Pacific Gyre and the Pacific sector of the Southern Ocean, where the supply of dissolved iron (DFe) and manganese (DMn) to the surface ocean is thought to regulate primary production and associated cycling of carbon and nutrient elements. The investigators will undertake shipboard and post-cruise measurements of dissolved aluminum (DAl), DFe and DMn in order to constrain (1) the magnitude of dust deposition to this ocean region and the fidelity of DAl and DMn as tracers of aeolian iron inputs; (2) the origin of deep-ocean DAl and DFe anomalies, and their implications for deep sources of these elements; and (3) the source and fate of hydrothermal DFe emissions from the deep ocean and their role in supporting Southern Ocean primary production. Project results, complemented by measurements of other trace chemical species made by collaborators on GP17-OCE, will advance the understanding of the processes that control the oceanic inventories and distributions of DAl, DFe and DMn, and their trajectories of future change.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.

国际研究计划 GEOTRACES 的目标是了解海洋中微量化学元素及其同位素的分布。海洋中微量元素的重要性在于它们作为海洋浮游植物必需的微量营养素（例如铁）、有毒物质（例如铅）以及过去和现在海洋过程的示踪剂（例如钍）。在该项目中，将测量在东南太平洋和邻近南大洋的科考航行期间收集的海水样本中两种微量营养素微量元素（铁和锰）和一种大气尘埃沉积示踪剂（铝）的溶解浓度，以便更好地了解这些微量营养素的输入及其对这些地区生物过程的影响。 化学分析将在海上近乎实时地进行，从而提供第一眼数据，为巡航采样策略和其他研究人员进行的分析提供信息。该项目涉及两个美国实验室，并将支持研究生和本科生的研究。美国 GEOTRACES GP17-OCE 探险队将重点关注穿越南太平洋环流和南大洋太平洋部分的横断面沿线的微量元素和同位素分布，其中溶解的铁 (DFe) 和锰 (DMn) 供应到表层海洋被认为调节初级生产以及相关的碳和营养元素循环。研究人员将对船上和巡航后的溶解铝 (DAl)、DFe 和 DMn 进行测量，以限制 (1) 该海洋区域灰尘沉积的程度以及 DAl 和 DMn 作为风积铁输入示踪剂的保真度； (2) 深海 DAl 和 DFe 异常的起源及其对这些元素深部来源的影响； (3) 深海热液 DFe 排放的来源和归宿及其在支持南大洋初级生产中的作用。项目结果，加上合作者在 GP17-OCE 上进行的其他痕量化学物质的测量，将增进对控制 DAl、DFe 和 DMn 海洋库存和分布及其未来变化轨迹的过程的理解。该奖项反映了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，NSF 的法定使命被认为值得支持。