In this study, we developed the vegetation prevalence model. This model takes into account the existence/nonexistence of vegetation and the resistance of willows above ground and their root systems to flowing water and sediment transport at different tree growth stages. The growth increment regarding various parts of a willow tree is estimated on the basis of the tree age. In the model, willows’ resistance to flowing water and sediment transport is varied with time to simulate each growth stage. The vegetation prevalence model was incorporated into a riverbed evolution analysis model for analyzing the mechanism and the contributing factors of thick and extensive vegetation growth. |