A nature-based exploration of resilience capacity in coastal settlements exposed to tsunamis along the southern Pacific coast

The speculation of coastal land for tourism and housing has led to the rapid urbanization of Chilean coastal settlements and to the reduction of critical ecosystems that contribute to resilience against tsunami hazards. This study analyzes the mitigative and adaptive capacities of these settlements based on their natural resources, focusing on differences across settlements with varying degrees of urbanization. Mitigative capacity refers to the ability to minimize the impact of a tsunami through bioshields like coastal forests, wetlands, and dunes in the Coastal Plane. Adaptive capacity encompasses longer-term resources that support recovery, such as food, water, and refuge provided by forests, prairies and agricultural land among others in the Coastal Range. Using spatial and multivariate analyses, 53 coastal settlements were evaluated, leading to three settlement clusters with distinct degree of urbanization, type of settlement (village or city), and differences in their latitudinal distribution and in the number of prairies and agricultural land in the Coastal Range. Results show no significant differences between settlement clusters and mitigative capacity. On the other hand, the study finds that cities' type of settlements, with greater prairie and agricultural land in the Coastal Range, particularly in central and northern Chile, show a higher capacity for adaptation, based on transportation and refuge available after the tsunami. This research highlights the crucial role of natural resources in both immediate disaster mitigation and long-term adaptation. Understanding the differences in resource availability among settlements can inform urban planning strategies to develop tsunami-resilient communities along Chile's southern Pacific coast.