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Cao, H.; Chen, Y.; Tian, Y., and Feng, W., 2016. Field investigation into wave attenuation in the mangrove environment of the South China Sea coast. Coastal mangroves form the land-sea interface and face an increasingly aggressive threat from ocean waves as a result of sea-level rise. This study investigates the buffering effect of mangroves on the coast of Leizhou Bay in the South China Sea under two different climates (normal windy weather and storm). By doing this, we aim to establish the exact wave damping rate due to the presence of mangroves and to study the wave and spectral characteristics of wave energy in the vegetated area. Wave gauges are mounted along a cross-shore transect to monitor the wave conditions during particular time periods. From the data analysis, we found that the recorded maximum significant wave height is 22.3 cm at the outermost station and remarkable wave damping was experienced within the mangrove troops of 100 meters. To evaluate the wave dissipation on the mudflat, an empirical expression is proposed on the basis of the field data. In this way, the net vegetation-induced wave dissipation is quantified separately. The spectral analysis of wave energy shows the modalities of frequency-dependent wave energy dissipation under different weather conditions. From the results, we conclude that the wave height was strictly subjected to the concurrent water depth even under the storm condition. The relative water depth (to the wave height) determined wave generation or dissipation on the mudflat. Despite the existence of dissipation by the mudflat, wave energy was majorly attenuated by the mangrove system. The wind growth of wave energy is of great significance when studying the spectral characteristics of wave energy during storm conditions. [ABSTRACT FROM AUTHOR]

Cao, H.; Feng, W., and Chen, Y., 2016. Numerical modeling of wave transformation and runup reduction by the coastal vegetation of the South China Sea. Vila-Concejo, A.; Bruce, E.; Kennedy, D.M., and McCarroll, R.J. (eds.), Proceedings of the 14th International Coastal Symposium (Sydney, Australia). Journal of Coastal Research, Special Issue, No. 75, pp. 830-835. Coconut Creek (Florida), ISSN 0749-0208. The aim of this study is to examine wave transformation and runup using a numerical model of coastal conditions including vegetation. Based on the previous field study, the drag coefficient was estimated using an analytical model. After that, numerical modeling of wave dissipation in SWASH (Simulating WAves until SHore) was conducted and validated with the observed data. Furthermore, calibrated SWASH was used to inspect the wave runup under vegetated and non-vegetated cases. For the flexibility of numerical modeling, We also used the numerical model to assess various vegetation parameters and beach slopes to inform the characteristics of wave runup reduction. The results of the model indicate that SWASH with proper parameters accurately simulated wave dissipation. Wave runup and setup were significantly reduced by the coastal vegetation. The numerical results suggest that vegetation parameters and beach slope are important factors when analyzing the wave runup reduction rate. [ABSTRACT FROM AUTHOR]