A numerical study demonstrates the effects of flooding on subsurface hydrological flowpaths and nitrate removal in anoxic groundwater in riparian zones with a top peat layer. A series of two-dimensional numerical simulations with changing conditions for flow (steady state or transient with flooding), hydrogeology, denitrification, and duration of flooding demonstrate how flowpaths, residence times, and nitrate removal are affected. In periods with no flooding groundwater flows horizontally and discharges to the river through the riverbed. During periods with flooding, shallow groundwater is forced upwards as discharge through peat layers that often have more optimal conditions for denitrification caused by the presence of highly reactive organic matter. The contrast in hydraulic conductivity between the sand aquifer and the overlying peat layer, as well as the flooding duration, have a significant role in determining the degree of nitrate removal.

中文翻译：

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河岸带洪水过程中缺氧地下水中硝酸盐去除的数值模拟

一项数值研究证明了洪水对地下水文流动路径的影响以及在具有顶层泥炭层的河岸带缺氧地下水中去除硝酸盐的影响。一系列具有变化条件的二维数值模拟，包括流动条件（稳态或瞬态泛滥）、水文地质学、反硝化作用和泛滥持续时间，展示了流动路径、停留时间和硝酸盐去除是如何受到影响的。在没有洪水泛滥的时期，地下水水平流动并通过河床排入河流。在洪水期间，浅层地下水被迫向上排放，通过泥炭层排出，泥炭层通常由于存在高反应性有机物而具有更理想的反硝化条件。砂含水层与上覆泥炭层之间的水力传导率对比，