Beach Changes Caused by Intermittent Supply of Sand from a Reef in Southern Part of Fonadhoo Island in the Maldives
摘要
On Maabaidhoo Island in Laame Atoll in the Maldives, a large amount of sand has supplied from the coral reefs since 2013. On Fonadhoo Island in the same atoll, sand supply from the coral reefs occurred in the same manner as that on Maabaidhoo Island. The sand movement on Fonadhoo Island was investigated using satellite images and field observations of the deposition and erosion along the shoreline on July 11, 2023. It was found that a large amount of sand was supplied from the coral reefs between 2018 and 2022 owing to the shoreward sand transport on Fonadhoo Island, resulting in an increase in foreshore area. This shoreward sand transport was confirmed by the observation that many streak patterns on the coral reefs approached the shoreline over time and connected to the shoreline, resulting in the formation of a berm on the foreshore. Moreover, it was found that the volume of sand increased by approximately 13,000 m3 during this event.