Collaborative Research: U.S. GEOTRACE GP17-OCE and GP17-ANT: Characterizing iron-binding organic ligands in the Southern Ocean and implications for iron cycling in the global ocean

合作研究：美国 GEOTRACE GP17-OCE 和 GP17-ANT：南大洋铁结合有机配体的特征及其对全球海洋铁循环的影响

• 批准号: 2300915
• 负责人: Kristen Buck
• 金额: $ 39.98万
• 依托单位: Oregon State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-11-01 至 2025-07-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2300915&HistoricalAwards=false
• 关键词: Collaborative; Research; U.S.; GEOTRACE; GP17

Iron is an essential element for life and plays an important role in defining how much atmospheric carbon dioxide is taken up into the ocean by phytoplankton. However, iron cycling is closely governed by the chemistry of seawater; nearly all iron in seawater is associated with various unknown organic compounds, called iron-binding ligands, which impact whether and how iron is utilized by organisms and the distribution of iron throughout the ocean. Detail understanding of the cycling of organic iron-binding ligands is necessary to understand iron cycling in the oceans and the connections between iron cycling and atmospheric carbon. The proposed research will be carried out as a part of US GEOTRACES expedition to test the hypothesis that the Southern Ocean is a globally significant source of iron-binding organic ligands, and that different sources of these organic molecules lead to different iron-ligand characteristics. The US GEOTRACES program is a large collaborative effort to sample ocean systems at high resolution for a suite of key trace elements and isotopes. The South Pacific and Southern Ocean regions targeted by the upcoming US GEOTRACES GP17 cruises are important locations of water mass formation and the subsequent transport of carbon and nutrients to the global ocean. Organic ligands produced in these regions thus have important implications for the stabilization, reactivity, and residence time of iron along the path of global water mass circulation and could impact the global oceanic inventory of dissolved iron. This project will measure the distribution of iron-binding organic ligands, and identify specific organic molecules that comprise these ligands, in field and experimental samples collected on upcoming US GEOTRACES cruises in the South Pacific (GP17-OCE) and Southern Ocean (GP17-ANT). These datasets will be utilized to conduct the first extensive intercalibration of the two most widely used approaches for characterizing iron-binding organic ligands, providing important insight into these datasets and how they can be synthesized to improve understanding of iron cycling in the oceans. All data from this project will be made publicly available. Project activities will provide educational and training opportunities for middle school, high school, undergraduate, and graduate students, and results will be shared with the public through the development of virtual reality modules and via local outreach events.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.

铁是生命的重要元素，在定义浮游植物二氧化碳将多少大气二氧化碳吸收到海洋中起着重要作用。然而，铁循环密切受海水化学的控制。海水中几乎所有的铁都与各种未知的有机化合物，称为铁结合配体，这会影响生物体是否以及如何利用铁以及在整个海洋中使用铁的分布。需要详细了解有机铁结合配体的循环，以了解海洋中的铁循环以及铁循环与大气碳之间的连接。拟议的研究将作为美国地理探险的一部分进行，以检验以下假设：南大洋是全球重要的铁结合有机配体的来源，并且这些有机分子的不同来源导致了不同的铁配体特性。美国的地理位置计划是一项巨大的合作努力，可为一系列关键的微量元素和同位素进行高分辨率采样海洋系统。即将到来的美国地理环境区GP17巡游针对的南太平洋和南部海洋地区是水质形成的重要位置以及随后将碳和养分运输到全球海洋的重要位置。因此，在这些区域中产生的有机配体对沿全球水质量循环道路的稳定，反应性和停留时间具有重要意义，并可能影响溶解铁的全球海洋清单。该项目将测量结合铁有机配体的分布，并确定在即将到来的南太平洋（GP17-OCE）和南部海洋（GP17-ANT）中收集的田间和实验样品中，这些特定有机分子在现场和实验样品中。这些数据集将用于对两种最广泛使用的方法来表征铁结合有机配体的第一个广泛的构图，从而为这些数据集提供了重要的见解，以及如何合成它们以提高对海洋中铁循环的理解。该项目的所有数据都将公开可用。项目活动将为中学，高中，本科生和研究生提供教育和培训机会，并通过开发虚拟现实模块和当地的外展活动与公众分享结果。该奖项反映了NSF的法定任务，并认为通过基金会的知识分子和更广泛的影响，通过评估来审查CRITERIA。