The Role of Green Infrastructure in Enhancing Flood Resilience: A Spatial Perspective

The aim of this study is to empirically assess the effectiveness of green infrastructure (GI) in South Korea as a way to enhance flood resilience. We applied a spatial analytical approach to examine the impact of GI on flood resilience. Specifically, we tested spatial dependence with Moran's I and local indicators of spatial association, addressing it with spatial lag and spatial error models. We compiled government data on GI and other regional attributes for 226 administrative districts in South Korea. Unlike previous studies that focused only on damage costs, this study incorporated both damage and recovery costs to calculate flood resilience costs. The findings show that flood resilience costs and GI distribution exhibit substantial spatial heterogeneity and significant spatial autocorrelation across local governments. Moreover, GI reduces flood resilience costs, although its effectiveness varies by type. No spatial spillover effect of GI on neighboring areas was identified, indicating that the impact of GI is localized and spatially confined. These results provide empirical evidence that GI plays a crucial role in strengthening local resilience against flood risk. The findings highlight the need to strengthen local resilience through spatially efficient expansion, hydrologically optimized design, and strategic allocation of GI, particularly considering flood vulnerability and interregional GI equity. By quantifying resilience costs and employing spatial analysis, this study advances both the theoretical understanding and the practical application of GI in flood-prone regions.