Abstract: Traditional groundwater resources management tends to focus on the fluctuation of water table itself while rarely care about the impact on the ecosystem caused by water table change. This paper developed the ecohydrology-based groundwater resources management approach through ecohydrological modeling. This approach integrates soil water content and groundwater level, taking into account the evapotranspiration under plant water stress. The process-based and distributed ecohydrological modeling is achieved via coupling soil water deficit and plant water stress. The simulated plant water stress index is used as an ecological indicator for groundwater mining management. The Yanqing Basin is taken as an example in this paper to demonstrate how this approach works. The impact of groundwater exploitation on ecohydrological processes is analyzed through the modeling for the years 1981-2000. Although it still needs further research on the ecological implications of plant water stress index, and model uncertainties and sensitivities, this study provides a quantitative ecohydrological indicator that could be used for sustainable groundwater resources management.

Key words: ecohydrological modeling, soil water deficit, plant water stress, groundwater