Collaborative Research: Iron Incorporation into Biogenic Silica

合作研究：将铁掺入生物二氧化硅中

• 批准号: 1658181
• 负责人: Ellery Ingall
• 金额: $ 30.97万
• 依托单位: Georgia Tech Research Corporation
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-03-01 至 2022-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1658181&HistoricalAwards=false
• 关键词: Collaborative; Research; Iron; Incorporation; into

Ocean research over the last several decades has increasingly shown the great importance of iron chemistry on marine biological processes. In certain areas of the ocean where iron is scarce, it can limit biological growth even though other essential nutrients like nitrogen and phosphorus are abundant. Consequently, to fully understand and quantify biological productivity in the ocean, a complete knowledge of all sources and sinks for iron is essential. The researchers funded for this project have already generated exciting preliminary data that suggest a potentially large, yet, unquantified pathway for iron removal. Diatoms, phytoplankton with shells made of silica, are shown to incorporate traces of iron into their shells, making it unavailable for rapid recycling or use by marine organisms in surface waters. Given the great abundance of diatoms in many parts of the ocean, this could represent a major, unstudied removal mechanism that regulates the concentration of iron in seawater. This research could transform current understanding of how iron is removed from the ocean, and it will impact understanding of both the chemical and biological processes involving iron in seawater. The investigator also plans outreach in K-12 schools by providing educational courses for Earth Science teachers and will support graduate student training in advanced chemical analysis and oceanography. High-resolution synchrotron-based chemical techniques will allow determination of the concentration and oxidation state of iron bound within diatom frustules. This analytical advance has created the ability for unique evaluation of iron sequestration into biogenic silica as a major pathway for iron removal from the ocean. Samples from the Pacific sector of the Southern Ocean have been collected in a previous CLIVAR field campaign and a subset of these are available for new synchrotron analysis of iron (Fe) with Near Edge X-ray Fluorescence Spectroscopy (Fe-NEXFS) and submicron scale X-ray fluorescence mapping, as well as a variety of other chemical characterizations. With these methods, the project will determine the importance of iron sequestered into biogenic silica as a new and unquantified loss term in the oceanic Fe cycle and examine the changing chemical complexes of iron during vertical transport of silica particles through the water column.

在过去的几十年中，海洋研究越来越多地表明了铁化学对海洋生物学过程的重要性。在铁很少的海洋地区，即使其他必需营养素（如氮和磷）丰富，它也可以限制生物生长。 因此，为了充分理解和量化海洋中的生物生产力，对铁的所有来源的完整知识至关重要。为该项目提供资金的研究人员已经产生了令人兴奋的初步数据，这表明了一种潜在的较大但未经量化的途径进行了去除铁的途径。硅藻是用二氧化硅制成的贝壳的浮游植物，可将铁的痕迹掺入其壳中，使其无法在地表水中快速回收或使用海洋生物使用。鉴于海洋许多地方的硅藻大量，这可能代表一种主要的，未研究的去除机制，可以调节铁在海水中的浓度。这项研究可能会改变人们对如何从海洋中去除铁的理解，并会影响对涉及海水中铁的化学和生物过程的理解。研究人员还通过为地球科学教师提供教育课程，计划在K-12学校进行宣传，并将支持高级化学分析和海洋学的研究生培训。基于高分辨率同步加速器的化学技术将允许确定硅藻丝体内铁结合的浓度和氧化态。这一分析进步创造了将铁固相化为生物二氧化硅作为从海洋中去除铁的主要途径的独特评估的能力。在先前的Clivar野外活动中，已经收集了来自南大洋太平洋地区的样本，其中一部分可用于对铁（FE）进行新的同步加速器分析，并具有近边缘X射线荧光光谱（FE-NEXFS）和亚尺寸X射线尺度X射线荧光映射，以及其他各种化学特征。通过这些方法，该项目将确定铁隔离为生物二氧化硅的重要性，这是海洋FE循环中一种新的且未量化的损失项，并检查二氧化硅颗粒通过水柱的垂直运输过程中铁的变化化学复合物。

项目成果

Relationship between Atmospheric Aerosol Mineral Surface Area and Iron Solubility

大气气溶胶矿物表面积与铁溶解度的关系

• DOI: 10.1021/acsearthspacechem.9b00152
• 发表时间: 2019
• 期刊: ACS Earth and Space Chemistry
• 影响因子: 3.4
• 作者: McDaniel, Mary Francis;Ingall, Ellery D.;Morton, Peter L.;Castorina, Erin;Weber, Rodney J.;Shelley, Rachel U.;Landing, William M.;Longo, Amelia F.;Feng, Yan;Lai, Barry
• 通讯作者: Lai, Barry

Enhanced Iron Solubility at Low pH in Global Aerosols

• DOI: 10.3390/atmos9050201
• 发表时间: 2018-05
• 作者: E. Ingall;Yan Feng;Amelia F. Longo;B. Lai;R. Shelley;W. Landing;P. Morton;A. Nenes;N. Mihalopoulos;K. Violaki;Yuan Gao;S. Sahai;Erin Castorina