| This study is an investigation of the impact of land-use on distributed groundwater recharge and discharge and dependent ecosystems. It was conducted in Western Jilin because it is an ecologically important, near-closed hydrologic basin with arid/semi-arid climatic conditions. With rapid population and economic growth, the region has witnessed intensive and extensive farming and groundwater use. This phenomenon has changed most of the original form of land-cover into mainly agricultural farmlands. This forms the basis of this study in the basin. The latest version of the traditional groundwater-modeling tool MODFLOW-2005 was extended with the SEEPAGE and WETSPASS PACKAGES and GIS. The model was calibrated using USGS-UCODE and comparing measured and simulated water table levels. It was then verified with measured stream discharges from the basin, which showed a good agreement. The integrated package efficiently complemented one another in handling the vegetation, flow and recharge and discharge aspects of the simulation, which were important in relating the groundwater response to the different land-uses. The study showed a strong connection between land-use and groundwater recharge and discharge in the basin. Forest vegetation was noted to specifically increase recharge in the area, while bare/impervious surfaces yielded very small recharge. Most remarkable, was the effectiveness of the forest vegetation in managing soil erosion. The water table was also noted to be declining with increasing groundwater use. Groundwater use is strongly related to agricultural cultivation since the basin is a typical farming zone. The study revealed important ecological changes in the region that can guide future land-use development decisions.
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