Trace metal marine geochemistry: speciation and coastal processes

痕量金属海洋地球化学：形态和沿海过程

• 批准号: 46507-2006
• 负责人: Orians, Kristin
• 金额: $ 2.16万
• 依托单位: University of British Columbia
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2008
• 资助国家: 加拿大
• 起止时间: 2008-01-01 至 2009-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=390671
• 关键词: Trace; metal; marine; geochemistry; speciation

Trace elements in seawater play important roles as nutrients, as tracers of ocean processes, and as contaminants.  Their biogeochemical cycling has implications for research in diverse areas such as the carbon-cycle, climate-change, ocean ecosystems, and environmental contamination.  Despite the recognized importance of trace elements, our ability to use this information is limited by uncertainties concerning their sources, sinks, internal cycling and chemical speciation within the ocean.  My research focuses on determining the distributions of selected trace elements (Al, Ga, Ti, Zr, Hf, Mn, Cu, Cd, Zn, Pb) in the Northeast Pacific, and in some cases their chemical speciation, to assess the sources, sinks, and internal cycling of these elements.  The aim is to evaluate the physical, chemical and biological processes regulating their distributions. This includes characterization of some of the metal-binding ligands which strongly influence trace element speciation in the oceans. Over the next few years I will focus on characterizing coastal sources and transport processes, including fluvial input, shelf exchange, upwelling and transport in mesoscale eddies.  Many of the elements of interest are known to have coastal sources, but the detailed origins and magnitudes of these sources are not known.  Rivers supply dissolved metals and suspended sediments to seawater and the continental shelf in this region, some metals are mobilized from the shelf sediments via diagenetic processes.  Eddies may carry these metals from the coastal region out into the subarctic gyre, an area where primary production is known to be limited by iron.  I propose to look at the effect of these sources on the distribution of selected trace metals in the northeast Pacific.  I also propose to look at the structure, abundance and distribution of the strong metal-binding organic ligands in various estuarine and coastal regimes, as well as in laboratory phytoplankton cultures.

海水中的微量元素作为营养物质、海洋过程的示踪剂和污染物起着重要的作用。它们的生物地球化学循环对碳循环、气候变化、海洋生态系统和环境污染等不同领域的研究都有影响。尽管微量元素的重要性已被公认，但由于其来源、汇、海洋内部循环和化学形态。我的研究重点是确定选定的微量元素的分布（Al，Ga，Ti，Zr，Hf，Mn，Cu，Cd，Zn，Pb），并在某些情况下进行化学形态分析，以评估这些元素的源、汇和内部循环。化学和生物过程调节它们的分布。这包括一些金属结合配体的特性，强烈影响微量元素的形态在海洋中。在接下来的几年里，我将专注于表征沿海来源和运输过程，包括河流输入，陆架交换，上升流和中尺度涡旋的运输。已知许多感兴趣的元素具有沿海来源，但这些来源的详细起源和大小尚不清楚。河流为该地区的海水和大陆架提供溶解的金属和悬浮沉积物，一些金属通过成岩作用从陆架沉积物中迁移出来。涡旋可能将这些金属从沿海地区带到亚北极环流中，这是一个已知的初级生产受铁限制的地区。我建议研究这些来源对东北太平洋选定的痕量金属分布的影响。我还建议研究结构，丰度和分布的强金属结合有机配体在各种河口和沿海制度，以及在实验室浮游植物培养。