Chemical and Biological Implications of Water Flow through Permeable Sediments

Taghon，Fuller，Kerkhof，Reimers：OCE-9872042 潮下带抽水现象是许多大陆架的一个常见特征，但人们对此知之甚少。 这组研究人员提出了一个假设，即陆架砂的低有机碳含量是有机物（OM）快速细菌矿化的副产品，由于底层水平流输送，OM和氧气的供应率很高 穿过上层沉积物 提出了实验室和现场研究。 在实验室中，PI建议在海水水槽中使用受控条件，以尝试测量海底地形、沉积物渗透性和流速的变化如何影响OM在这些沙子中的循环。 现场部分将在新泽西海岸外的永久海底观测站（LEO 15）进行，据认为，在该观测站，通过桑迪沉积物的平流驱动通量会发生。 这项研究的结果将使PI量化沉积通量，提高我们对这一过程的理解。 这将对我们理解沿海海洋中有机物和相关元素的循环产生广泛影响。

Taghon, Fuller, Kerkhof, Reimers : OCE-9872042 The occurrence of subtidal pumping is a common, but poorly understood feature of many continental shelves. This group of PIs propose to test the hypothesis that the low organic carbon content of shelf sands is a by-product of rapid bacterial mineralization of organic matter (OM), fueled by a high rate of supply of OM and oxygen as bottom water is advected through the upper layer of sediment. Both laboratory and field studies are proposed. In the lab, the PIs propose to use controlled conditions in a seawater flume to attempt to measure how variations in seabed topography, sediment permeability and flow velocity affect the cycling of OM in these sands. The field component will be conducted at the site of a permanent seabed observatory (LEO15) off the coast of New Jersey, where advection driven fluxes through sandy sediments are thought to occur. The results of this study will allow the PIs to quantify sedimentary fluxes and improve our understanding of this process. This will have a broad impact on our understanding of the cycling of organic matter and associated elements in coastal oceans.