The role of breakwaters on the rehabilitation of coastal and mangrove forests in West Kalimantan, Indonesia

The result showed that the breakwaters built in Karimunting and Penibung Bay were successful to reduce the amount of coastal erosion up to 70% within 22 years. On the contrary, the breakwaters built in the Bay of Sungai Duri could not reduce the coastal erosion. The effects of breakwaters on mangrove rehabilitation were clear, which can be observed on the colonization rate of Avicennia marina and reforestation of Rhizophora sp. in Karimunting Bay. The abrasion of shoreline still occurred although there were breakwaters built. It might be caused by the construction of breakwaters were segmented. The condition worsens by activities of beach sand excavation.