Determination of spatially and temporally highly detailed groundwater recharge in porous aquifers by a SVAT model

An extended version of the SVAT model TRAIN is used to model groundwater recharge grid based (500 x 500 m) on a daily time step for porous aquifers without lateral flow components. The conceptual soil model of the HBV rainfall runoff model was integrated into the SVAT model. One empirical soil parameter was calibrated on measured percolation of 20 lysimeters in Baden-Wurttemberg, one of the federal states in the south-west of Germany. The model proved suitable to simulate monthly percolation (groundwater recharge) under very different conditions. After the calibration of the model at the point sites the model was applied to a study area. The study area is part of an extensive porous aquifer in the Upper Rhine Valley. The nature of the conceptual soil model allows an easy parameterisation from digital soil data sets of the scale 1.200 000 together with land use data. Different land uses are modelled separately within each pixel. The model can provide monthly groundwater recharge as input data for groundwater modelling as well as long term groundwater recharge, as a basis for sustainable management of groundwater resources. (C) 2001 Elsevier Science Ltd. All rights reserved.