Understanding the role of the dynamics impacts of hyporheic zone processes on water balance and nutrient dynamis at the groundwater - surface water Interface of floodplains

本研究的目的是研究两种不同类型河流在基流条件下对地下水-地表水相互作用的水物理和水化学控制作用，并评估该界面上的哪些因素影响氧化还原敏感元素通量的转化。为了实现这些总体目标，我们制定了三个目标。目的1-水文物理学对河流连通性的控制：在两个含水层性质相似但水文和地貌环境不同的地点，评估地下水-地表水界面水通量的空间和时间变异性。目标2-河流连通性对水化学和营养盐通量的控制：确定控制这两个地点氧化还原敏感元素通量的关键物理特征，以便在次河流尺度上建立含水层到河流化学通量平衡的概念模型。目的3定量分析水平衡和养分动态：量化地下水地表水界面上的水交换和养分运移。目标1和目标2的实验结果将被应用到Iwan模式中，以提高模式在反映潜流带过程方面的充分性。

The aims of this research are to investigate the hydrophysical and hydrochemical controls on groundwater - surface water interactions in two different river types under baseflow conditions, and to evaluate what factors at this interface influence the transformation of the flux of redox-sensitive elements. To address these general aims, three objectives have been formulated. OBJECTIVE 1 - HYDROPHYSICAL CONTROLS ON RIVER CONNECTIVITY: To evaluate the spatial and temporal variability of water fluxes across the groundwater-surface water interface at two sites with similar aquifer properties but in contrasting hydrological and geomorphologic environments. OBJECTIVE 2 - RIVER CONNECTIVITY CONTROLS ON HYDROCHEMISTRY AND NUTRIENT FLUXES: To determine the key physical characteristics that control the flux of redox-sensitivity elements at the two sites, allowing the development of a conceptual model of aquifer to river chemical flux balance at a sub-reach scale. OBJECTIVE 3 ¿ QUANTITATIVE ANALYSES OF WATER BALANCE AND NUTRIENT DYNAMICS: To quantify water exchange and nutrient transport at the groundwater ¿ surface water interface. The experimentally gained results of objective 1 and 2 will be implemented into the IWAN model in order to improve the model adequacy regarding the reflection of hyporheic zone processes.