Limiting factors for riparian ecosystem were previously considered to be riparian habitat structure, water flow variability, sedimentation and erosion. Recent scientific research have started to focus their attention to the feedback between form and function in fluvial ecosystems considering that not only geomorphology controls riparian vegetation dynamics, but also riparian vegetation controls geomorphology. Erosion-sedimentation processes significantly change the channel of the river and its surroundings and the sediment movement indicator is the critical value of the shear stress. This contribution deals with the impact of vegetation on the erosion-sedimentation processes in fluvisols during flood events. Selected vegetation characteristics and their effects on the humus horizons in fluvisols were assessed at the selected area of the River Schwechat followed by modelling of the shear stress during flood events.