Study on storm-effects on beach-coral reef system - Taking the response of qinglangang coast on no. 1409 typhoon rammasun as an example

Coral reefs distribute extensively along tropical coasts in China. The interactional behavior of beach-coral reef system is the key to understanding its morphodynamic process. Based on repeated field surveys before and after the Typhoon Rammasun,the paper discussed the storm-effects on beaches and its relationship with coral reefs along Tongguling-Gaolongwan coast in Hainan. The results showed that the most active zone during Typhoon Rammasun was above MSL,which was characterized by backshore scarp,shoreline retreat,berm erosion and the reduction of beach face. The storm-effects on beaches are closely related to the condition of nearshore coral reefs. In the case of absence or destruction of coral reefs,the storm-effects on beaches significantly increased by 3-6 times Mean Profile Change (MPC) value. Coral reefs can provide effective protection for adjacent beach by mean of wave dissipation through reef flat. The characteristics of the storm-effects on beach-coral reef system are controlled by the wave dissipation of reefs and the sediment buffering of beaches. Four types of storm-response modes of beach-coral reef system were summarized.