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痕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是海洋浮游植物必需的微量营养素(如铁)、有毒物质(如铅)以及过去和现在海洋过程的示踪剂(如钍)。在这个项目中，将测量在东南太平洋和邻近南大洋进行研究巡航期间采集的海水样本中两种微量营养素(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，从而提供第一次对数据的一瞥，这些数据将为巡航抽样战略和其他调查人员进行的分析提供信息。该项目涉及两个美国实验室，将支持一名研究生和本科生的研究。美国地质遗迹GP17-OCE探险队将重点研究横跨南太平洋环流和南大洋太平洋部分的一条横断面上的微量元素和同位素分布，在那里，溶解铁(DFE)和锰(DMN)的供应被认为调节着初级生产和相关的碳和营养元素的循环。调查人员将对溶解铝、DFE和DMN进行船上和邮轮后测量，以便约束(1)该大洋区域尘埃沉积的规模和DAL和DMN作为风成铁输入示踪剂的保真度；(2)深海DAL和DFE异常的来源，及其对这些元素深层来源的影响；(3)深海热液DFE排放的来源和去向及其在支持南大洋初级生产方面的作用。项目结果与GP17-OCE合作者对其他痕量化学物种的测量相补充，将促进对控制DAL、DFE和DMN海洋清单和分布的过程以及它们未来变化轨迹的理解。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。