A three-dimensional numerical study of the effect of vegetation removal on the stability of riverbanks: insights into best practice vegetation management

1. Home
2. Publications
3. Online Library
4. A three-dimensional numerical study of the effect of vegetation removal on the stability of riverbanks: insights into best practice vegetation management

It is well established that vegetation plays a crucial role in controlling the stability of slopes. Its removal or degradation, caused by wildfires, droughts, or anthropogenic action, often acts as a contributing factor for landslide initiation, particularly on slopes already close to failure. This study proposes a comprehensive methodology that integrates field data, phenomenological interpretation, and numerical modelling to quantitatively assess root-induced mechanical reinforcement and provide general insights into best practices for vegetation in high landslide susceptibility areas.

A three-dimensional finite element model was developed for a riverbank where a rainfall-induced shallow landslide occurred (Øysand, Norway), confined to an area previously cleared of natural vegetation. A back-analysis of the event was performed by applying monitored precipitation as boundary condition, enabling validation of the phenomenological diagnosis and providing a reliable numerical analysis. The model was then tested under a vegetated scenario by incorporating a reinforced superficial layer, allowing the determination of the minimum root-induced mechanical increase in soil shear strength parameters required to prevent failure, consistent with the absence of landslide occurrence in nearby uncleared areas. Finally, the validated model was used for a scenario analysis to investigate the effects of different extents and geometrical patterns of vegetation clearance on slope stability.

3rd International Workshop on Soil-Vegetation-Atmosphere Interaction (RootS2025)

2c. Numerical modelling of the behaviour of rooted soils and boundary value problems under static and dynamic loading conditions