Assessing Hazard Vulnerability, Habitat Conservation, and Restoration for the Enhancement of Mainland China's Coastal Resilience

Worldwide, humans are facing high risks from natural hazards, especially in coastal regions with high population densities. Rising sea levels due to global warming are making coastal communities' infrastructure vulnerable to natural disasters. The present study aims to provide a coupling approach of vulnerability and resilience through restoration and conservation of lost or degraded coastal natural habitats to reclamation under different climate change scenarios. The integrated valuation of ecosystems and tradeoffs model is used to assess the current and future vulnerability of coastal communities. The model employed is based on seven different biogeophysical variables to calculate a natural hazard index and to highlight the criticality of the restoration of natural habitats. The results show that roughly 25% of the coastline and more than 5 million residents are in highly vulnerable coastal areas of mainland China, and these numbers are expected to double by 2100. Our study suggests that restoration and conservation in recently reclaimed areas have the potential to reduce this vulnerability by 45%. Hence, natural habitats have proved to be a great defense against coastal hazards and should be prioritized in coastal planning and development. The findings confirm that natural habitats are critical for coastal resilience and can act as a recovery force of coastal functionality loss. Therefore, we recommend that the Chinese government prioritizes restoration (where possible) and conservation of the remaining habitats for the sake of coastal resilience to prevent natural hazards from escalating into disasters. Plain Language Summary Coastal populations are especially at risk from sea-level rise (SLR), induced storm surges, and other natural hazards. Therefore, it becomes essential to analyze the current and future vulnerabilities of coastal regions to natural hazards. Furthermore, it is desirable for the policy and the decision making to propose the suitable approaches for the resilience enhancement. This paper analyzes the current and future vulnerability of mainland China's coast to the SLR-induced natural hazards using a natural hazard index incorporating a coupled approach to vulnerability and resilience. The results show that the restoration of lost mangroves (where possible) and conservation of remaining coastal natural habitats can reduce the future coastal vulnerability by 45%. This study confirms that natural habitats are significant for coastal resilience and the governments should prioritize them for the sake of coastal resilience to mitigate the impacts of natural hazards.