A Comprehensive Review on the Role of Vegetation in Open Channels and its Impact on Sediment Transport and Flow Dynamics

This paper provides a comprehensive review of recent research on the role of vegetation in open channels and its impact on sediment transport and flow dynamics. Vegetation plays a crucial role in influencing flow characteristics and sediment deposition, with factors such as vegetation density, porosity, shape, flexibility, and height significantly affecting flow turbulence and sediment transport. Different vegetation arrangements, including patches, are found to alter sediment deposition rates and turbulence structure. The review examines laboratory, field, and modelling studies that investigate the effects of vegetation characteristics on mass transport and flow behaviour, highlighting the methods used to assess vegetation porosity and sediment transport rates. Additionally, the paper explores the swash-zone dynamics, where high velocities and suspended sediment concentrations contribute to shore line erosion and accretion. Despite limited research in this area, studies in both low-energy reflective beaches and high-energy dissipative beaches have provided insights into sediment transport processes in the swash-zone. These processes, including the role of groundwater influx and out flux, must be considered in any model of sediment transport in the swash-zone. This paper underscores the importance of vegetation and swash-zone dynamics in sediment transport and coastal morphology.