Assessment of Mangrove as Natural Protection Buffer for Coastal Areas

Mangrove forests have been reported to effectively lower the impact of tsunami, storm surge waves plus high and moderate waves especially after deadliest Ocean Tsunami 2004. Many parameters or aspects have been taken look on during previous studies by researches, scientist, lecturers and students to investigate the effectiveness of mangroves in dissipating waves optimally through physical and numerical conducts.

In this paper, a review on the effectiveness of mangroves in protecting coastal areas has been provided and the empirical researches have been conducted by analyzing few derived empirical relationships by previous researches and field measurement has been done in coastal mangroves system in Kuala Gula, Bagan Serai and Pantai Lekir, Lumut, Perak to validate the empirical relationships. The study areas consisted of bare mudflat, abruptly changing into muddy tidal flat overgrown with mangroves. Leveling staffs and measuring tapes were used to measure the wave height, water level and also the geometry of mangroves. The measurements were conducted in October 2014 where it is in the transition between two monsoons; the Southwest Monsoon and the Northeast Monsoon. Since there are few obstructions during the site measurement, only one place is used to validate the parameter which is in Pantai Lekir, Lumut, Perak.

For the effectiveness of the wave attenuation by the mangroves, equation by Bao’s (2011) has been modified in to validate the wave attenuation in Kuala Gula. The structure of mangrove roots is not considered in the calculation. New coefficients obtained represent the mangrove roots structure.
Comparison between Darymple’s formula and Raleigh distribution on wave energy dissipation has been made which shows big difference between the results of both equations which is about 90%.