Dynamic exposure to urban lakefront spaces: Unveiling the role of social infrastructure in shaping visitation

Abstract

Access to blue spaces, such as lakes and waterfronts, operates at the nexus of physical and mental well-being, as well as the broader agendas of sustainable urbanization. Despite their importance, the patterns of dynamic exposure to urban lakefront spaces, i.e., areas surrounding lakes within cities, and the role of social infrastructure in influencing how urbanites encounter and visit lakefront spaces remain insufficiently explored. Drawing on the Pearl River Delta (PRD) in China as a site of rapid urban transformation, we use fine grained mobile phone data to chart and interpret the spatial and temporal patterns of lakefront exposure. A Light Gradient Boosting Machine (LightGBM) model, validated through 10-fold cross-validation (R²≈0.7), is employed to examine the effects of eight types of social infrastructure with split and gain importance. The results reveal a variegated landscape of exposure, with weekday and weekend visitations diverging across four distinct lakefront types: urban lifelines, weekend havens, quiet waters, and workday blues. These findings emphasize the role of mixed-use development, public transit, and compact urban form in equitable and vibrant blue-space development. By advancing an analytic framework that integrates human mobilities and urban lakefront spaces, this study enriches the understanding of blue space exposure and underscores the importance of purposefully designed social infrastructures in supporting leisure, physical activity, and social interactions.