Intra-urban inequalities in opportunities for pedestrian mental well-being: a GIScience framework using 15-minute isochrones and spatial clustering

Abstract Active commuting offers important environmental, economic, and health benefits, yet urban inequalities shape who can access these benefits. This paper analyzes the relationship between pedestrian mobility and mental well-being by examining how environmental and socioeconomic attributes associated with well-being—tree density, vegetation cover (NDVI), air and noise pollution, property values, and safety—are spatially distributed in two contrasting urban contexts: São Paulo (Global South) and Lisbon (Global North). Using a GIS-based framework, we constructed 15-minute walking isochrones for 68,807 pedestrians and integrated environmental and socio-demographic indicators through spatial overlay, correlation, and clustering. Results show that conditions associated with mental well-being are unevenly distributed: greener, safer, and less polluted areas are disproportionately linked to higher-income and more educated groups, while disadvantaged populations face greater exposure to risks such as air pollution and unsafe pedestrian environments. Spatial clustering identified four distinct clusters in São Paulo and three in Lisbon, highlighting how socio-spatial inequalities structure active commuting conditions in both cities. Conceptually, the study demonstrates that opportunities for mental well-being are shaped by the spatial organization of urban environments. Methodologically, it shows how GIScience can operationalize individual exposures and reveal hidden intra-urban disparities, providing a transferable framework for comparative research and actionable evidence for policies aimed at equitable and healthier cities.