Studies of the Decomposition of Organic Matter in the Marine Environment

这项研究继续研究有机物的分解，有机物构成了海洋中碳的主要部分。这项研究旨在进一步确定有机物在海洋水柱中分解的途径和速率，从表层水域的生产，到水柱中的再矿化带，再到底层沉积物的保存。有机物的分解是控制海水和沉积物化学成分的主要过程之一。在全球范围内，有氧分解是海洋沉积物降解的主要途径，厌氧过程消耗的有机物要少得多。然而，大多数碳保存发生在缺氧系统中，通常是有机物沉降率最高的沿海海洋沉积物。了解有机质分解和碳保存的控制是解释沉积碳含量变化的关键，因此也是解释海洋古生产力的关键。本研究的主要目的是研究颗粒物中甲胺类物质中甲烷的生成，测定有机物的吸附和解吸对其分解速率和机理的影响，确定有氧和缺氧条件对分解的影响，并探索细胞表面酶在浮游植物和细菌分解氨基酸和胺中的作用。

This study continues research on the decomposition of organic matter, which comprises a major fraction of carbon in the ocean. The study is directed toward further defining pathways and rates of organic matter decomposition in the oceanic water column, from production in surface waters, through the zones of remineralization in the water column, to preservation in the underlying sediments. The decomposition of organic matter is one of the major processes controlling the chemical composition of seawater and sediments. On a global scale, oxic decomposition is the major pathway of degradation in marine sediments, with anaerobic processes consuming much less organic matter. However, the majority of carbon preservation occurs in anoxic systems, typically coastal marine sediments where organic matter sedimentation rates are highest. Understanding the controls on organic matter decomposition and carbon preservation is a key to interpreting changes in sedimentary carbon content, and thus paleoproductivity of the oceans. The major goals of this research are to investigate the formation of methane from, methylamines in particulate matter, to measure the effects of adsorption and desorption of organic compounds on their decomposition rates and mechanisms, to determine the influence of oxic vs anoxic conditions on decomposition, and to explore the use of cell-surface enzymes in the decomposition of amino acids and amines by phytoplankton and bacteria.