Evaluation of Sand Supply from Coral Reef - Example of Carbonate Beachesnear Point Kin in Okinawa

On a coral reef coast near Point Kin located in central Okinawa, a large-scale excavation of the sandy beach was carried out by the American armed forces after WWII and sandy beach disappeared. However, after the excavation, the sandy beach was rapidly recovered. In this study, the rate of sand supply from the reef was estimated on the basis of change in foreshore area after the excavation of the shoreline area by using aerial photographs. It was concluded that sand supply of 0.5-0.8 m3/m/yr could be anticipated in the long term.