Soluble and Colloidal Iron-Binding Organic Ligands in the Surface Water of Subtropical North Atlantic and North Pacific Oceans

副热带北大西洋和北太平洋表层水中的可溶性和胶体铁结合有机配体

• 批准号: 0220978
• 负责人: Jingfeng Wu
• 金额: $ 29.98万
• 依托单位: University of Alaska Fairbanks Campus
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-09-01 至 2006-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0220978&HistoricalAwards=false
• 关键词: Soluble; Colloidal; Iron; Binding; Organic

OCE-0220978A PI from the University of Alaska plans to measure concentrations of Fe and Fe-binding ligands in the soluble (0.02 um) and the colloidal phase (0.02-0.4 um) of surface waters from the BATS and HOT regions to understand the chemical and physical speciation of Fe. Samples will be separated into the soluble and colloidal phase using a new microfiltration technique developed by the PI. Iron concentrations will be measured by an isotope dilution-high resolution inductively coupled plasma mass spectrometry microanalytical method. The thermodynamic stability constants and kinetic rate constants of Fe-complexing natural ligands in the soluble and colloidal phases will be determined by the competitive ligand equilibration/cathodic stripping voltammetric method. The PI also plans to assess the spatial and temporal variability of these parameters at these two sites. Results from this study will provide useful constraints for models to determine the biological availability of soluble and colloidal Fe, the fate of Fe from dust inputs to the surface ocean and the Fe limitation on nitrogen fixation.

阿拉斯加大学的 OCE-0220978A PI 计划测量 BATS 和 HOT 区域地表水的可溶相 (0.02 um) 和胶体相 (0.02-0.4 um) 中 Fe 和 Fe 结合配体的浓度，以了解 Fe 的化学和物理形态。 使用 PI 开发的新型微滤技术将样品分离为可溶相和胶体相。 铁浓度将通过同位素稀释高分辨率电感耦合等离子体质谱微分析方法进行测量。 Fe络合天然配体在可溶相和胶体相中的热力学稳定常数和动力学速率常数将通过竞争配体平衡/阴极溶出伏安法测定。 PI 还计划评估这两个地点这些参数的空间和时间变化。 这项研究的结果将为模型提供有用的约束，以确定可溶性和胶体铁的生物利用度、灰尘输入海洋表层的铁的命运以及铁对固氮的限制。