The Importance of Sorption to Minerals on Microbial Reactivity and Organic Matter Preservation

地球化学家们早就认识到矿物表面在保护和保存水生沉积物中海洋有机质（OM）方面的潜在重要性。该提案旨在通过更详细地评估有机矿物与矿物表面积比（OM:SA）来进一步了解有机质保存，该PI和其他PI最近表明该比率有助于评估海洋沉积物中的有机质保存。拟议的测量旨在回答海洋地球化学中关于形成和塑造OM:SA关系的因素和过程的基本问题。广泛的方法将用于评估海洋沉积物，包括：探测技术的组合（x射线光电子能谱（XPS），紫外线光氧化，密度分馏）；吸附萃取有机物，了解矿物相；进行微生物降解实验。PI将在对比氧化还原环境和OM:SA设置下收集的样品上进行这些实验。拟议的研究建立在PI先前进行的成功实验的基础上，应该会使我们对海洋沉积物中OM保存的理解取得重大进展。

Keil (OCE-9711792) ABSTRACT Keil OCE-9711792 Geochemists have long recognized the potential importance of mineral surfaces in protecting and preserving marine organic matter (OM) in aquatic sediments. This proposal seeks to further out understanding of OM preservation by evaluating in more detail the organic mineral to mineral surface area ratio (OM:SA) which has recently been shown by this PI and others to be useful for evaluating OM preservation in marine sediments. The proposed measurements are aimed at answering fundamental questions in marine geochemistry about the factors and processes that form and mold the OM:SA relationship. A wide range of approaches will be used to evaluate marine sediments, including: a combination of probing techniques (X-ray photoelectron spectroscopy (XPS), UV photooxidation, density fractionation); adsorbing extracted organic matter to know mineral phases; and, conducting microbial degradation experiments. The PI will conduct these experiments on samples collected from contrasting redox environments and OM:SA settings. The proposed studies build on successful experiments previously conducted by the PI and should lead to a significant advancement in our understanding of OM preservation in ocean sediments.