How do spatial factors of green spaces contribute to flood regulation in urban areas? A systematic mapping approach

Flooding is increasing in urban areas around the world, leading to loss of life and property damage, and cities are using urban green spaces (UGS) for flood regulation. The spatial attributes of UGS have an important role in controlling and regulating urban flooding, and there is a need for a systematic map on how spatial factors of UGS, such as shape, size, location, or connectivity, impact flooding in urban areas. The objectives of this study are to analyze and synthesize published material to evaluate the impacts of the spatial dimensions of UGS on flood regulation and to identify knowledge gaps and future research directions. Pertinent literature was reviewed and synthesized using the systematic mapping method. The results of this study show that previous research on spatial configuration have examined how variables such as slope, DEM, green space coverage, and landscape shape index impact runoff reduction. Slope was found to be an important, but not determining factor in flood regulation. There is a need for further research on how the geographic context of urban regions, including climatic conditions and land use changes, impacts UGS functionality. Additionally, there is a need for further research on how the spatial configuration of UGS impacts flood vulnerability and intensity, two under-addressed yet important topics in urban flooding.