Pathways of ecosystem-based disaster risk reduction: A global review of empirical evidence

Ecosystems provide valuable services in reducing the risks of disasters through various pathways, which are increasingly recognized as sustainable strategies for disaster management. However, there remains limited information on the underlying ecological processes of risk reduction. This paper addresses this gap by synthesizing ecological mechanisms and evaluating the 'level of evidence' and 'scale of use' through a review of 64 peer-reviewed research articles published between 2015 to 2022. These research articles covered nine types of disasters, predominantly floods (42.19 %), followed by urban heat waves (18.75 %), storm runoff (10.94 %), coastal erosion (9.38 %), tsunamis (4.69 %), and avalanches and landslides (6.25 % each). The level of evidence supporting ecological processes for disaster risk reduction is moderate, as is the 'scale of use'. Results show that there are a few studies describing the mechanism of ecosystem-mediated risk reduction and are mostly limited to the causal relationship. Empirical evidence demonstrates that forest and freshwater ecosystems buffer the risk of urban heat through processes such as transpiration, solar radiation interception, and evaporative cooling, while flood risks are mitigated by enhancing evapotranspiration, reducing water runoff time, and facilitating infiltration rates. Coastal erosion is reduced by dissipating wave energy and through beach nourishment, which facilitates ecological succession. The review underscores that hazard attenuation depends on factors such as forest type (e.g., species composition, age structure, and area), and landscape characteristics (e.g., matrix, composition and configuration). Moreover, the geographic scope of published research is largely confined to developed countries and the global north. Multidisciplinary research involving ecologists and disaster experts is imperative to address existing knowledge gaps and enhance the integration of ecosystem-based adaptation into disaster risk reduction strategies.