A coupled modeling of surface-subsurface fluid flow, sediment transport and flow bed change has been proposed for water resources management in forest area. In the developed model, the surface water and subsurface water interactions, erosion of slope and production of solid particles by the surface flow, transport/sedimentation of solid, and resultant surface deformation are considered. Applicability of the model to the actual field has been checked through the comparison of the simulated and observed results such as hydrographs, suspended-load concentrations, and so on. Consistent and preferable matching was attained between them for all of the observed years.
