GEOTRACES Arctic Section: Shipboard determination of key trace elements

GEOTRACES 北极部分：关键微量元素的船上测定

• 批准号: 1439253
• 负责人: Christopher Measures
• 金额: $ 36.68万
• 依托单位: University of Hawaii
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-01-01 至 2018-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1439253&HistoricalAwards=false
• 关键词: GEOTRACES; Arctic; Section; Shipboard; determination

In this project, investigators participating in the 2015 U.S. GEOTRACES Arctic expedition will make shipboard measurements of dissolved aluminum, iron, and manganese in seawater, ice, snow, and melt pond samples collected during the cruise. In common with other national initiatives in the International GEOTRACES Program, the goals of the U.S. Arctic expedition 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. Some trace elements are essential to life, others are known biological toxins, and still others are important because they can be used as tracers of a variety of physical, chemical, and biological processes in the sea. This project will be of particular importance to the success of the overall Arctic expedition because measurements of trace metals in seawater require highly-specialized clean sampling techniques to prevent contamination. Accordingly, the shipboard measurements made by this scientific team will allow for the early detection and rectification of any sample contamination problems while still at sea. In terms of broader impacts, education and training of the next generation of marine trace element scientists, including undergraduate and graduate students, as well as public outreach will be key aspects of this project.The shipboard determinations of dissolved aluminum, iron, and manganese in this study will provide near real-time insights into the distribution of these parameters, which can be used to potentially modify sampling strategies and can also be used to identify any systemic sampling contamination issues during the GEOTRACES Arctic expedition. Definitive data for dissolved iron and manganese will be produced by shore-based ICP MS, a type of mass spectrometry capable of detecting metals at very low concentrations. However, since dissolved aluminum data cannot be determined by shore-based ICP MS, the shipboard data set collected as part of this project will provide the definitive data set for this key GEOTRACES parameter. In addition, the researchers will undertake high resolution water sampling in the upper 10 m of the water column to characterize the trace metal distribution in this highly stratified region, which cannot be sampled by a conventional rosette. This sampling will be conducted from the edge of ice-floes or a small boat, away from the disturbing effects of the research vessel.

在该项目中，参加 2015 年美国 GEOTRACES 北极探险的研究人员将对航行期间收集的海水、冰、雪和融水池样本中溶解的铝、铁和锰进行船上测量。与国际地理追踪计划中的其他国家举措一样，美国北极探险的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，并确定这些分布对变化的敏感性。环境条件。有些微量元素是生命所必需的，有些是已知的生物毒素，还有一些很重要，因为它们可以用作海洋中各种物理、化学和生物过程的示踪剂。该项目对于整个北极探险的成功特别重要，因为海水中痕量金属的测量需要高度专业的清洁采样技术以防止污染。因此，该科学团队进行的船上测量将允许在海上时及早发现和纠正任何样本污染问题。就更广泛的影响而言，下一代海洋微量元素科学家（包括本科生和研究生）的教育和培训以及公众宣传将是该项目的关键方面。船上溶解铝、铁和锰的测定这项研究将提供对这些参数分布的近实时洞察，这些参数可用于潜在地修改采样策略，也可用于识别 GEOTRACES 北极探险期间的任何系统采样污染问题。溶解铁和锰的确切数据将通过岸基 ICP MS 产生，这是一种能够检测极低浓度金属的质谱分析方法。然而，由于溶解铝数据无法通过岸基 ICP MS 确定，因此作为该项目一部分收集的船上数据集将为这一关键 GEOTRACES 参数提供明确的数据集。此外，研究人员还将在水柱上部10 m处进行高分辨率水采样，以表征这个高度分层区域中的痕量金属分布，这是传统花环无法采样的。这种采样将从浮冰边缘或小船进行，远离研究船的干扰影响。