The overall aim is to improve our ability to predict growth of eelgrass and (fine-grained) sediment transport, by being able to model the interaction of sediment dynamics as a function of eelgrass shoot density/biomass, as well as the eelgrass growth dynamics as a function of sediment dynamics. Essentially, this study focuses on establishing changes in critical bed shear stress for erosion and deposition. Time series of sediment, hydrodynamic and biological parameters provide a data basis for understanding the temporal dynamics and quantify critical shear stress and sedimentation/ erosion.