Abstract
We investigated tsunami mitigation effect of mangrove forest in 2009 Samoa tsunami using field survey and numerical model. Field surveys revealed that the wetland with 100 m width of mangrove forest reduced 80 % of tsunami inundation depth. We also found that mangrove forest significantly prevented tsunami debris from damage on the village behind forest. We modeled the propagation of 2009 Samoa tsunami and compared the numerical results with observed data. As results the numerical results are approximately consistent with the measured data. Using the numerical simulation of tsunami including the resistance of a mangrove forest we investigated the tsunami reduction effects of the mangrove forest in Samoa Island.
