Application of Hydro-morphodynamic Modelling in Coastal Salt Marsh Management

Abstract Salt marshes are widespread in estuarine coastal areas and are one of the most productive natural ecosystems in the world. More importantly, the role of salt marshes in coastal protection is of increasing interest, as salt marshes significantly reduce wave height and stabilize substrates. However, the application of hydrodynamic models for coastal salt marsh management is still uncommon. In this study, TELEMAC is used to set up a hydro-morphodynamic model to simulate the dynamic process in the study area. After that, the influence of hydrodynamic stress on the salt marshes under natural conditions was analysed and the feasibility of applying artificial structures to restore salt marshes was discussed. Finally, the long-term evolution of salt marsh platform is modelled. The results show that salt marsh vegetation is strongly influenced by coastal dynamics. The artificial restoration measures such as submerged dikes have the potential to restore or rehabilitate salt marshes by attenuating the currents on tidal flats. The long-term marsh evolution contains both platform raising and channel incision, which forms the unique landscape of tidal salt marsh. The research results of the study can provide theoretical support for the management and restoration of coastal salt marsh wetlands and contribute to disaster prevention and mitigation in the coastal areas.