Morphodynamic Modeling of Alluvial Rivers and Floodplains

This article gives and overview of the large spectrum of models based on first principles (mass and momentum conservation) developed in the field of fluvial morphodynamics. After describing the main morphological features of alluvial rivers and their floodplains, the chapter gives a general classification of the modeling approaches available in literature. Next, it delineates the morphodynamic problem and briefly summarizes the procedures used to solve the governing equations, depending on the spatial and temporal scales resolved. The problem of the closures arising from depth-averaging is then discussed. The various models are grouped with reference to the morphological features to be simulated. The dynamics of small-scale and large-scale bedforms in single-thread straight rivers and the modeling of braided, anastomosing and meandering rivers are then considered. Finally, the simulation of the coupled river-floodplain evolution is tackled. The chapter ends with a delineation of the modeling perspectives.