ATTENUATION AND LONGITUDINAL MIXING IN VEGETATED WAVE-CURRENT FLOW

The material quantities and associated costs of studied in full, and this paper aims to provide an insight adaptation infrastructure for climate change is expected based on experimental findings. to rise, in the coming century (Jonkman et al., 2013). Therefore, using nature-based soft coastal defences to safeguard coastlines will result in economic advantages in addition to environmental benefits. Coastal vegetation (mangroves, salt marshes, sea grass, etc.) is a source of drag, and hence waves propagating over them lose energy. By damping near bed velocities, seagrass reduce local resuspension and promote the retention of sediment, stabilizing the seabed (Fonseca and Cahalan, 1992). Coastal vegetation can be used alone to minimize disturbances caused to day-to-day activities by rough sea conditions, and sometimes soft coastal defences can be coupled with hard coastal defences (Jackson, 2014) to reduce the wave loads induced on hard defences (e.g., a salt marsh in front of a seawall). Seagrasses grow mainly in physically dynamic regions which are exposed to both tide and wave generated currents, such as shallow regions along coastal margins and within estuaries (Thomas and Cornelisen, 2003).