Mangrove stilt root morphology modeling for estimating hydraulic drag in tsunami inundation simulation
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The submerged tree volume and the projection area of mangroves play a significant role in damping tsunami inundation flow with a distinct root formation above ground. We modeled the stilt root morphology of the Rhizophora sp., especially to incorporate into a hydraulic drag of tsunami inundation simulation. The equivalent Manning’s roughness coefficient has been used as the hydraulic drag of mangroves for the computation of inundation flow [Yanagisawa et al. (Coast Shelf Sci 81: 27–37, 2009)], but it could not elucidate the effectiveness under different tree conditions. The field data from 18 sample trees in Ranong Province, Thailand, were measured. The total number of primary roots, the root height at trunk, and the root-spread distance, the root diameter, and the vertical root angle from trunk could be estimated with the diameter of the breast height. The quadratic equation expressed the root curve of the primary stilt root, and functions to estimate root volume and projected area were derived by the integration of the equation that will be used to calculate drag force in tsunami simulation.
KeywordsMangrove Stilt root Morphology Tsunami inundation Hydraulic drag
We thank Mr. Sukrid Krataichan, Chief of Laem Son National Park, Ranong, Department of National Park, wildlife and Plant, Thailand, for his assistance in the field survey.
- Giesen W, Wulffraa MZ, Scholten L (2007) Mangrove guidebook for southeast Asia. FAO, Weltlands International, RomeGoogle Scholar
- Harada K, Imamura F (2005) Effects of coastal forest on tsunami hazard mitigation—a preliminary investigation. In: Advances in natural and technological hazards research, vol 23. Springer, Netherlands, p 279–292. doi: 10.1007/1-4020-3331-1_17
- Sato K (1978) Studies on the protective functions of the mangrove forest against erosion and destruction (I). The morphological characteristics of the root system of Yaeyama hirugi (Rhizophora mucronata LAMK). Sci Bull Coll Agric, University Ryukyus 25:615–630Google Scholar
- Soares MLG, Schaeffer-Novelli Y (2005) Above-ground biomass of mangrove species. I. Analysis of models. Estuar Coast Shelf Sci 65:1–18Google Scholar
- Tomlinson PB (1986) The botany of mangrove. Cambridge University Press, New YorkGoogle Scholar