Vertical Structure of Wave Induced Currents, Orbital Velocity and Turbulence Observed in Natural Vegetation

Abstract

Vertical structures of hydrodynamics under wave conditions were investigated using live plants in a large-scale wave flume. The effect of vegetation on hydrodynamics were analyzed for regular wave cases. The interaction of waves and emergent vegetation under regular waves significantly affect wave-induced motion and turbulence intensity. Coastal vegetation motion affected the water particle kinematics so that the vertical distribution of water particle velocity showed a large deviation from linear wave theory. Also, the vegetation motion increased turbulence intensity in the middle of water column and this caused a different vertical distribution of turbulent kinetic energy compard to the control case with no vegetation. In addition to the turbulence kinetic energy level, the vegetation changed the anisotropy characteristics of turbulence, decreasing vertical turbulent component.