Collaborative research: Does dissolved organic matter influence the concentrations and distributions of trace elements in the Arctic Ocean?

合作研究：溶解有机物是否影响北冰洋微量元素的浓度和分布？

• 批准号: 1504137
• 负责人: Ronald Benner
• 金额: $ 18.09万
• 依托单位: University of South Carolina at Columbia
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-08-15 至 2018-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1504137&HistoricalAwards=false
• 关键词: Collaborative; research; Does; dissolved; organic

The investigators propose to take advantage of three already-funded research expeditions to investigate the distribution of cycling of natural dissolved organic material (DOM) in the Arctic Ocean and in particular its relationship to the cycling of trace metals such as iron. The Arctic Ocean has experienced significant changes over the last 30 years, including declining sea ice and increasing continental runoff. The Arctic is considered a harbinger of changes in the carbon and hydrological cycles, with important implications for regional and global climate. How the physical, chemical and biological structure of the Arctic Ocean will respond to such fundamental changes is poorly understood. The proposed research will provide novel insights about dissolved organic matter and its role in trace element cycling. Recent studies provide tantalizing data indicating the transport and fate of DOM and trace metals are closely linked in the Arctic Ocean, and suggesting an important role of continental runoff and sea ice formation in the distribution of DOM and associated trace metals.Water samples will be collected and analyzed for dissolved organic carbon and nitrogen, amino acids, lignin phenols and detailed optical characterization of chromophoric DOM (CDOM) during 3 expeditions in 2015 aboard the USCGC Healy, the German ice breaker Polarstern, and the Japanese research vessel Mirai. The combined optical and molecular analyses will be used to distinguish and quantify terrigenous and marine DOM and their potential interactions with trace elements. A probe for measuring in situ fluorescence of DOM will be interfaced with the CTD/rosette for high-resolution mapping and real-time examination of interesting features to guide sampling efforts. The U.S. and German expeditions are part of the international GEOTRACES program, whose goals are to identify processes and quantify fluxes that control the distributions of key trace elements and isotopes in the ocean, and to establish the sensitivity of these distributions to changing environmental conditions. The U.S. Arctic GEOTRACES project has established a central outreach program for this research program including meetings with local communities in Alaska, recruiting a high school teacher to participate in the expedition and interact with schools in the US and beyond via a blog. These investigators will tie into the existing GEOTRACES outreach efforts and will link interested Texas and South Carolina Schools to the expedition blog. This project will train 3 graduate students in and expose about 6 undergraduate students to research in the Arctic Ocean. The goal of the teaching component of this project is to provide students with an experience that demonstrates the scientific method, from development of goals and hypotheses to experimental design and presentation of results. Findings of this project will be conveyed to the public using established links with local newspapers where students describe research projects in their own words.

研究人员建议利用三个已资助的研究考察来调查北冰洋中天然溶解有机物质（DOM）的循环分布，特别是其与铁等微量金属循环的关系。过去 30 年来，北冰洋经历了重大变化，包括海冰减少和大陆径流增加。北极被认为是碳和水文循环变化的先兆，对区域和全球气候具有重要影响。人们对北冰洋的物理、化学和生物结构将如何应对这种根本性变化知之甚少。拟议的研究将为溶解有机物及其在微量元素循环中的作用提供新的见解。最近的研究提供了诱人的数据，表明 DOM 和微量金属的运输和归宿在北冰洋密切相关，并表明大陆径流和海冰形成在 DOM 和相关微量金属的分布中发挥着重要作用。将收集水样并在 2015 年德国破冰船 USCGC Healy 的 3 次探险中分析了溶解的有机碳和氮、氨基酸、木质素酚以及发色 DOM (CDOM) 的详细光学特征Polarstern 和日本科考船 Mirai。结合光学和分子分析将用于区分和量化陆地和海洋 DOM 及其与微量元素的潜在相互作用。用于测量 DOM 原位荧光的探针将与 CTD/玫瑰花结连接，以进行高分辨率绘图和有趣特征的实时检查，以指导采样工作。美国和德国的探险活动是国际 GEOTRACES 计划的一部分，其目标是识别控制海洋中关键微量元素和同位素分布的过程和量化通量，并确定这些分布对不断变化的环境条件的敏感性。美国北极GEOTRACES项目为此研究计划建立了一个中心外展计划，包括与阿拉斯加当地社区举行会议、招募一名高中教师参加探险并通过博客与美国及其他地区的学校互动。这些调查人员将结合现有的 GEOTRACES 外展工作，并将感兴趣的德克萨斯州和南卡罗来纳州学校与探险博客联系起来。该项目将培养 3 名研究生并让约 6 名本科生参与北冰洋研究。该项目教学部分的目标是为学生提供展示科学方法的体验，从目标和假设的制定到实验设计和结果呈现。该项目的研究结果将通过与当地报纸建立的联系向公众传达，学生用自己的话描述研究项目。