Most climate scenarios predict an increase in potential evapotranspiration and an increase in seasonal differences in precipitation for the northwest European region. The combination of changes in precipitation and potential evapotranspiration influences the groundwater system. As a result the vegetation types that strongly depend on groundwater levels and seepage will change also. The possible effects of climate change on groundwater dependent vegetation was modelled through a chain of climate, groundwater and an ecological model in the basin of the Kleine Nete in Belgium. The climate of the reference period (1961 – 1991) was compared with 27 different European climate scenarios for the period 2071-2100. For each climate scenario the future groundwater levels were calculated with a dynamic infiltration and groundwater model. Calculating the groundwater levels for a large number of climate scenarios allows analysing the uncertainty on the future groundwater system. Time dependent dynamic modelling enables to differentiate the seasonal changes in groundwater level and seepage. Compared to the reference period, future groundwater levels are in general expected to be much lower in late summer and autumn while in spring the groundwater levels will be close to the current situation. Changes in groundwater level and seepage have a direct impact on water availability for vegetation. They also have an influence on soil processes which determine the acidity of the soil and nutrient availability. The combined effect of these changing factors on the potential occurrence of some typical groundwater dependent vegetation types was calculated with a eco-hydrological tool NICHE. The NICHE uses field data a several hundreds of vegetation plots to predict the possible occurrence of vegetation types. The outputs of all 27 climate scenarios were used to determine the possible range of impact of climate change. For some vegetation types a high negative impact is expected, others are less sensitive or do even profit from the expected ...