The Effectiveness of Tsunami Bore Reduction by Hibiscus Tiliaceus Coastal Vegetation: An Experimental Study

Tuty Amaliah; Muhammad Arsyad Thaha; Riswal Karamma; Mukhsan Putra Hatta

doi:10.48084/etasr.18479

Authors

Tuty Amaliah Civil Engineering Department, Faculty of Engineering, Hasanuddin University, Gowa, Indonesia
Muhammad Arsyad Thaha Civil Engineering Department, Faculty of Engineering, Hasanuddin University, Gowa, Indonesia
Riswal Karamma Civil Engineering Department, Faculty of Engineering, Hasanuddin University, Gowa, Indonesia
Mukhsan Putra Hatta Civil Engineering Department, Faculty of Engineering, Hasanuddin University, Gowa, Indonesia

Volume: 16 | Issue: 3 | Pages: 37048-37055 | June 2026 | https://doi.org/10.48084/etasr.18479

Received: 2 March 2026 | Revised: 19 April 2026, 2 May 2026, and 4 May 2026 | Accepted: 8 May 2026 | Online: 6 June 2026

Corresponding author: Tuty Amaliah

Abstract

Tsunamis pose a serious threat to coastal areas, where rapid development increases the potential for damage and loss of life. Effective mitigation measures are needed, including nature-based solutions involving coastal vegetation. This study experimentally investigated the effectiveness of Hibiscus Tiliaceus coastal vegetation in reducing tsunami bores generated by the dam-break method. Records of tsunami bore characteristics are presented, along with reductions in tsunami bore height for various vegetation widths and tsunami bore characteristics. The results show that H. tiliaceus vegetation effectively reduces tsunami bore height through mechanisms of hydraulic resistance and energy dissipation. An increase in the vegetation width ratio (W_v/h_b) correlates with higher tsunami bore reduction coefficients and a greater percentage of tsunami bore reduction. At a vegetation width (W_v) of 6 m and h₀ of 0.1 m, a 34.14% reduction compared to the "no-vegetation" conditions was observed. The R² values for the dimensionless parameters of the tsunami bore reduction coefficient were R² = 0.4005 at h₀ = 0.08 m and R² = 0.6498 at h₀ = 0.1 m, indicating instability and the potential for overtopping of coastal vegetation, but a positive trend was observed. These findings indicate that vegetation width, initial water depth, and tsunami bore characteristics are crucial for planning ecosystem-based disaster risk reduction strategies in vulnerable coastal areas.

Keywords:

tsunami mitigation, dambreak method, coastal vegetation

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