Shuto (1987) outlined different ways in which coastal forests may reduce tsunami impact and asserted that a forest is effective for several reasons: 1)it stops driftwood and other flotsam; 2)it reduces water flow velocity and inundation depth; 3)it provides a lifesaving snare for people swept off land by a tsunami run-down; and 4)it amasses wind-blown sand and create dunes, which serve as a
natural barriers against tsunamis.