Collaborative Research: The role of soluble Mn(III) in the biogeochemical coupling of the Mn, Fe and sulfur cycles

这项由特拉华大学海洋科学与政策学院和俄勒冈健康与科学大学环境和生物分子系统系的研究人员进行的研究将探讨可溶性锰(III)在锰的生物地球化学循环中的重要性。到目前为止，大多数关于海洋环境中的锰的研究都没有考虑到介于可溶还原态(Mn(II))和更难溶的氧化态(Mn(IV))之间的中间氧化态--Mn(III)。Mn(III)在海洋系统中的存在和稳定性，特别是在氧水平降低的海洋系统中，改变了这些位置上以及在有氧和低氧环境之间的锰的动力学和稳定性、溶解性、去向和运输。目前还不了解这一点，拟议的研究有望提供有关锰循环的新信息，并可能是变革性的研究。PI已经开发了新的方法来检查环境中的Mn(III)水平，这种能力将有助于成功实现项目--S目标。这些研究不仅将侧重于了解锰在其不同氧化态之间的循环，而且将确定分层沿海水域和沉积物孔隙水中锰(II)的浓度和分布。本研究还将探讨Mn(III)与Fe和S在调节和影响Mn的生物地球化学循环中的潜在重要作用，这两个元素都是主要海洋化学循环的重要组成部分。更好地了解锰的生物地球化学将不仅为对海洋中金属循环感兴趣的科学家提供信息，也将为那些专注于氧化还原过渡区研究的科学家提供信息。拟议的研究具有国际成分，调查人员已制定计划，向各级学生和社区广泛传播他们的研究结果。首席调查员在教育、研究生和博士后支持和指导方面有着深厚的历史，这将在目前的赠款下继续下去。

The research conducted by investigators in the School of Marine Science and Policy at the University of Delaware and within the Department of Environmental and Biomolecular Systems of Oregon Health and Science University will examine the importance of soluble Mn(III) in the biogeochemical cycling of Mn. To date, most studies of Mn in marine environments have not considered Mn(III), the intermediate oxidation state between the soluble reduced state (Mn(II)) and the more insoluble oxidized state (Mn(IV)). The presence and stability of Mn(III) in marine systems, especially those where oxygen levels are reduced, changes the dynamics and stability, solubility and fate and transport of Mn in these locations, and at interfaces between oxic and low oxygen environments. This is not understood at present and the proposed research is poised to provide new information concerning the Mn cycle and is potentially transformative research. The PIs have developed new methods to examine Mn(III) levels in the environment and this capability will bolster the successful accomplishment of the project?s goals. The studies will not only focus on understanding the cycling of Mn between its various oxidation states but will determine the concentration and distribution of Mn(II) in stratified coastal ocean waters and in sediment porewaters. The study will also examine the potentially important role of Mn(III) in mediating and influencing the biogeochemical cycling of Mn with that of Fe and S, which are both important components of the major ocean chemical cycles. A better understanding of the biogeochemistry of Mn will inform not only scientists interested in metal cycling in the ocean but also those focused on studies across redox transition zones. The proposed research has an international component and the investigators have developed plans to broadly disseminate their results to students at all levels and to the community. The Principal Investigators have a strong history in education and graduate student and post-doctoral support and mentoring and this will continue under the current grant.