Integration of Eco-DRR and hybrid defense system on mitigation of natural disasters (Tsunami and Coastal Flooding): a review

Ecosystem-based disaster risk reduction (Eco-DRR) is a concept of reducing the risk to natural hazards by avoiding the developments and settlements in disaster-prone areas by using a well-structured ecosystem as a natural buffer to protect the people and physical properties. Alternatively, the hybrid defense system (HDS) is a combination of ecosystem and engineered infrastructures used to avoid the disaster risk in identified places that are highly vulnerable to natural hazards. Vegetation buffers and engineered structures are useful methods that can be used to reduce the wave energy in association with destructiveness and controlling of floating debris accumulation. The effectiveness of ecosystem and engineered structures may change with either the orientation or arrangement of the vegetation buffer and the type of structure used. The vegetation buffer’s drawback is the limitation of the energy reduction of giant tsunamis and storm surges and its strength to withstand against natural disasters’ destructive forces. The primary objective of this article is to review the critical points of the evidence and the use of Eco-DRR and HDS for impact mitigation of tsunami and storm surges. Hence, the following four suggestions are proposed to reduce disaster risk by: (1) trapping the floating debris carried by the tsunami as a secondary measure, (2) studying how to reduce the destructiveness energy of a tsunami, (3) forming an effective method of HDS, and 4) developing a sustainable coastal environment.