Numerical simulation of detached breakwaters for mangrove restoration in Bengkalis Island, Indonesia

Abstract

This paper presents the application of detached breakwater to reduce wave energy for protecting mangrove planting site. Initial planting of mangroves still needs seawater for their growth, but they will be distracted by the big wave. How is the detached breakwater should be designed for this purpose is the objective of this research. This research simulated the wave propagation at the existing condition and under some alternative designs of detached breakwater to find out the optimum design of detached breakwater for mangrove planting site. The CADMAS-SURF is a numerical model that was used for the simulation. Bengkalis coast in Indonesia was picked up as study area of this research. The mangrove degradation and the severe coastal abrasion have occurred in this area for long period. The simulation result shows that in the high tide condition, the wave height and wave velocity at the mangrove plantation area are about 1.12 m and 3.86 m/s respectively in the case of the existing condition. In this case, the initial mangrove plantation cannot be applied because it will be destroyed by the wave. By applying breakwater both for rubble mound type and vertical wall type, the wave height and the wave velocity were reduced to 0.69 m, 2.39 m/s and 0.72 m, 2.31 m/s respectively. In this case, the initial mangrove plantation can be applied because it will not be destroyed by the wave.

Relationship of Coastline and Mangrove Area in West Rangsang - Indonesia

“…Utilizing satellite imagery from Landsat thematic mapper (TM) and LDCM satellite (Landsat-8), the changes that occurred on the beach and mangrove from 1997 to 2017 were calculated to obtain their correlation. If the relationship can be revealed, the results can describe all shallow beach-marshes in the neighbour region and the most east coast of Sumatra because of their similarity in coastal morphology [13], [14]. So this research can serve a new scientific report in monitoring coastline and mangrove relations on the east coast of Sumatra Island.…”

Environmental communication based on tourism management for mitigation of abrasion disasters

“…Bengkalis Island, as a peat island, is highly vulnerable because the soil is subject to erosion of up to thirty meters every year. The coastal erosion is enhanced by the bog-burst [1]. Environmental damage is of course the result of deforestation, industry, cutting down mangrove forests, land conversion and excessive exploitation of natural resources.…”