Collaborative Research: US GEOTRACES Pacific Section-Shipboard Al, Mn and Fe

合作研究：美国GEOTRACES太平洋剖面-船载铝、锰和铁

• 批准号: 1237034
• 负责人: Peter Sedwick
• 金额: $ 17.3万
• 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: 2012
• 资助国家: 美国
• 起止时间: 2012-09-01 至 2017-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1237034&HistoricalAwards=false
• 关键词: Collaborative; Research; US; GEOTRACES; Pacific

The 2013 GEOTRACES Eastern Pacific Zonal transect cruise will transit from the highly productive coastal upwelling region off Peru to the stratified oligotrophic waters of the South Pacific subtropical gyre on its way to Tahiti. A range of subsurface oxygen depleted water and sedimentary inputs from the Peru margin will be encountered, as well as hydrothermal vents at 15°S on the East Pacific Rise (EPR). Scientists from the University of Washington and Old Dominion University plan to analyze seawater samples for dissolved and total-dissolvable aluminum (Al), manganese (Mn), and iron (Fe) in water column samples. The dissolved Al, Mn, and Fe in samples from the upper water column (1000 m depth) will be analyzed onboard to ensure samples being collected are uncontaminated, as well as samples from west of the EPR at hydrothermal plume depths. The shipboard analyses will be augmented by shore-based analyses of water column samples from all depths, as well as analyses of total-dissolvable Al, Mn, and Fe, which will complement the direct analyses of particulate metals undertaken by other GEOTRACES investigators. Results will be used to test the following hypotheses concerning the sources and cycling of Al, Mn and Fe in the ocean: (1) when Aeolian inputs are relatively constant, dissolved Al concentrations in surface waters vary as a function of biological production; (2) concentration maxima of dissolved Al, Mn, and Fe in subsurface waters of the Eastern Pacific oxygen minimum zone are the result of lateral transport from the continental margin by means of resuspension and remobilization; and (3) values about ambient levels with conservative behavior will be encountered in the neutrally buoyant plume about the East Pacific Rise ridge crest for dissolved Fe and Al. As regards broader impacts, results from the study would be disseminated to the public via lectures, the internet, and press releases. One graduate and one undergraduate student from the University of Washington would be supported and trained as part of this project.

2013年GEOTRACES东太平洋地带性横断面邮轮将在前往塔希提岛的途中，从秘鲁附近生产力高的沿海上升区过渡到南太平洋副热带环流的分层少营养水域。将遇到来自秘鲁边缘的一系列地下耗氧水和沉积输入，以及东太平洋隆起(EPR)15°S处的热液喷口。来自华盛顿大学和老道明大学的科学家计划分析海水样本中的溶解和全溶解铝(Al)、锰(Mn)和铁(Fe)。来自上层水柱(1000米深)的样品中溶解的铝、锰和铁将在船上进行分析，以确保收集的样品没有受到污染，以及来自EPR以西热液羽流深度的样品。船上的分析将通过对所有深度的水柱样本进行岸上分析，以及对全溶铝、锰和铁的分析来加强，这将补充其他GEOTRACES调查人员对颗粒金属的直接分析。研究结果将用于检验下列关于海洋中铝、锰和铁的来源和循环的假设：(1)当风沙输入相对恒定时，表层水中的溶解Al浓度随生物生产的变化而变化；(2)东太平洋氧极小区次表层水中溶解Al、Mn和Fe的浓度极大值是通过再悬浮和再动员从大陆边缘横向输送的结果；(3)在东太平洋隆起脊脊附近的中性浮力羽状物中，将遇到溶解Fe和Al的保守水平值。至于更广泛的影响，研究结果将通过讲座、互联网和新闻稿向公众传播。作为该项目的一部分，华盛顿大学的一名毕业生和一名本科生将得到支持和培训。