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

本研究的目的是探讨基流条件下两种不同河型地下水-地表水相互作用的水物理和水化学控制，并评价该界面上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，制定了三个目标。目标1 -河流连通性的水物理控制：评估两个地点地下水-地表水界面的水通量的时空变异性，这两个地点的含水层性质相似，但水文和地貌环境却截然不同。目标2 -河流连通性对水化学和养分通量的控制：确定控制两个地点氧化还原敏感元素通量的关键物理特征，从而建立一个子河段尺度上含水层与河流化学通量平衡的概念模型。目的3水平衡和养分动力学定量分析：定量研究地下水和地表水界面的水交换和养分输送。将目标1和目标2的实验结果应用到IWAN模型中，以提高模型在反射隐隐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.