Masatoshi Endo, Akio Kobayashi, Takaaki Uda, Yasuhito Noshi, Susumu Onaka


In the southern part of Sanur Beach in Bali, beach erosion has occurred between groins after extensive beach nourishment, resulting in shoreline rotation between the groins. The cause of shoreline changes was investigated by field observations, including a bathymetric survey and the sampling of seabed materials, and numerical simulations of beach changes were carried out using Noshi et al.’s model. It was concluded that the shoreline rotation was triggered by the dredging of the reef flat, which caused a change in the wave direction on the reef flat due to the diffraction of waves.


coral reef; Bali; Sanur Beach; excavation of reef flat; shoreline change


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