<Dl> <Dt> Backshore </Dt> </Dl> <P> The backshore is always above the highest water level point . The berm is also found here which marks the boundary between the foreshore and backshore . Wind is the important factor here, not water . During strong storms high waves and wind can deliver and erode sediment from the backshore . </P> <Dl> <Dt> Dunes </Dt> </Dl> <P> The dunes are typical of a barrier island, located at the top of the backshore . Dunes are made by the wind . See Coastal Dunes for more information . The dunes will display characteristics of typical aeolian wind blown dunes . The difference here is that dunes on a barrier island typically contain coastal vegetation roots and marine bioturbation . </P>

What is the difference between a barrier island and a barrier spit