Advancing the Understanding of Hydrologic Connectivity between Kettle Holes and Adjoining Groundwater System using a Hybrid Modelling Approach

设想的研究的主要目标是量化和放大地下水和壶孔之间的通量交换。为此，将采用水的稳定同位素（18 O和2 H或D）与完全集成的水文模型（HydroGeoSphere，HGS）以及混合机器学习算法相结合。该项目通过采取以下四个方法步骤实现了这一目标：（1）根据稳定水同位素特征方法提供的分类，在德国Uckermark地区选择补给、流通和排放壶孔类型作为试验壶孔;此外，壶穴及其邻近地下水的水化学成分对判别补给的有效性，（2）构建和校准/验证局部尺度的高分辨率HGS模型，即试验釜孔，并提取试验/模拟釜孔与其相邻地下水域之间的通量交换;（3）用稳定水同位素方法估算的地下水流入量与HGS模型计算的地下水流入量进行验证;因此，将应用高技能偏差校正算法来校正同位素方法导出的地下水流入中反映的可能的系统偏差;（4）开发元模型，用于将模拟的壶孔-地下水通量交换放大到未模拟的壶孔。

The key objective of the envisaged research is to quantify and upscale the flux exchange between the groundwater and kettle holes. To that end, stable isotopes of water (18O and 2H or D) in combination with a fully integrated hydrological model (HydroGeoSphere, HGS) as well as a hybrid machine learning algorithm will be employed. The project attains the objective by taking the following four methodological steps: (1) selecting a recharge, flow-through, and discharge kettle hole type as the pilot kettle holes in the Uckermark region, Germany based on a classification provided by a stable water isotopic signature approach; in addition, the effectiveness of hydrochemistry compositions of the kettle holes and their adjacent groundwater for identification of recharge, flow-through, and discharge kettle hole types will be assessed; (2) constructing and calibrating/validating a high resolution HGS model for a local scale, namely the pilot kettle holes and extracting the flux exchange between the pilot/modelled kettle holes and their adjoining groundwater domain; (3) validating the groundwater inflow estimated using the stable water isotopic signature approach against that of calculated by the HGS model; as a result, a high skill bias correction algorithm will be applied to correct the possible systematic biases reflected in the isotopic approach-derived groundwater inflow; (4) developing meta-models for upscaling the modelled kettle hole-groundwater flux exchange to the unmodeled kettle holes.