we applied regression models in order to examine the relationship between wave height and cross-shore distances to the forest. The results show that wave height decays exponentially and is significantly related to distance (Figure 3). All 92 exponential regression equations of five research areas with different mangrove forest species are highly significant with P values of < 0.001 and R2 > 0.95. The exponential reduction of wave height in mangroves can be explained by the dense network of trunks, branches and above-ground roots of the mangrove trees, increasing bed roughness, causing more friction and dissipating more wave energy (Quartel et al. 2007).