GEOTRACES: Speciation intercalibration of iron and copper in seawater

痕量金属的清除和生物吸收强烈地受氧化还原状态和有机络合物的形成的影响。 为此，南加州大学的一位研究人员建议将铁（Fe）和铜（Cu）的形态测量纳入GEOTRACES相互校准练习。 最初，将在参加2009年太平洋GEOTRACES相互比较航行之前，对2004年SAFE航行期间收集的冷冻样品，使用阴极溶出伏安法测定铁和铜的有机络合作用。 配体结合强度和浓度的结果将与计划参与相互校准工作的其他研究者进行比较。 此外，还将对铁的氧化还原形态进行相互比较，几个小组将在2009年太平洋GEOTRACES相互校准巡航和2008年与斯克里普斯海洋学研究所的一名科学家合作前往墨西哥南部的机遇号巡航中测量Fe（II）。 研究人员计划使用化学发光法测量海水中的Fe（II）浓度，并将结果与其他参与者获得的值进行比较，关于更广泛的影响，将编写一份用户手册，详细说明成功收集海水样本并对铁和铜以及其他生物活性金属进行形态测量所需的协议，并提供给科学界。

Scavenging and biological uptake of trace metals are strongly influenced by redox state and the formation of organic complexes. For this reason, an investigator from the University of Southern California proposes to include speciation measurement of iron (Fe) and copper (Cu) into the GEOTRACES intercalibration exercise. Initially, organic complexation of Fe and Cu using cathodic stripping voltammetry methods would be determined on frozen samples collected during the 2004 SAFE cruise prior to participating in the 2009 Pacific GEOTRACES intercomparison cruise. Results for ligand binding strengths and concentrations would be compared with other investigators who are planning to participate in the intercalibration effort. In addition, redox speciation would be intercompared for iron, with several groups measuring Fe(II) on the 2009 Pacific GEOTRACES intercalibration cruise and on a cruise of opportunity in 2008 to southern Mexico in collaboration with a scientist from Scripps Institute of Oceanography. The investigator plans to measure Fe(II) concentrations in seawater using the chemiluminescence method and results would be compared with values obtained by other participants.As regards broader impacts, a User's manual detailing the protocols required to successfully collect seawater samples and make speciation measurements for iron and copper, as well as other bioactive metals, would be created and made available to the science community.