Hydrogen Cycling and Its Relationship to Carbon Remineralization in Anoxic Marine Environments

氢是厌氧成岩作用的关键中间体 有机碳。 氢分压在以下方面是重要的： 控制发酵途径和理论论证 表明产氢率很高。 此外，本发明还提供了一种方法， 对氢的竞争可能有助于确定 硫酸盐还原和甲烷生成的相对重要性（以及 可能是沉积物中的铁还原）。 H2也是一个重要的 产甲烷沉积物中甲烷的前体（包括淡水 海洋）。 然而，现有的数据相对较少， 允许详细讨论氢与氮之间的关系 地球化学和自然环境中的碳成岩作用。 斯克兰顿研究了氢的分布和循环， 厌氧沉积物中的乙酸盐，并已发现 在这些系统中氢的周转是非常迅速的。 生产率和消费率似乎几乎相同 (no氢的净释放或吸收），并且似乎与 在沉积物中的空间耦合（发生在“集群”）。 然而，测得的“表观”氢气生产率是 远低于醋酸盐产量的预测值 率同时测量，这表明文物可能 仍然存在于生产率的测量中。 斯克兰顿 建议估计在原位氢生产率使用 新的方法与非常薄的沉积层，以确定 一些脂肪酸和氢之间的关系 沉积物中的浓度，并将我们的数据集扩展到 包括相对简单的产甲烷系统。

Hydrogen is a Key intermediate in the anaerobic diagenesis of organic carbon. Hydrogen partial pressures are important in controlling fermentation pathways, and theoretical arguments suggest hydrogen production rates are high. In addition, competition for hydrogen can be instrumental in determining the relative importance of sulfate reduction and methanogenesis (and possibly iron reduction) in sediments. H2 is also an important precursor for methane in methanogenic sediments (both freshwater and marine). However, relatively few data are available which permit detailed discussion of the relationship between hy>rogen geochemistry and carbon diagenesis in natural environments. Scranton has studied the distribution and cycling of hydrogen and acetate in anaerobic sediments for several years and has found that hydrogen turnover in these systems is very rapid. Production and consumption rates appear to be virtually identical (no net release or uptake of hydrogen) and appear to be closely coupled spatially (occurring in "clusters") in the sediments. Measured rates of "apparent" hydrogen production, however, are much lower than would have been predicted from acetate production rates measured simultaneously, suggesting that artifacts may remain in the measurements of production rates. Scranton proposes to estimate in situ hydrogen production rates using a new approach with very thin layers of sediment, to determine the relationship between a number of fatty acids and hydrogen concentrations in the sediments, and to extend our data set to include the relatively simpler methanogenic systems.