Untangling the Interplay between Impervious Surface Landscape Metric, Thermal Environment, and Air Pollution: A Seasonal Mediation Analysis in Wuhan

Urban morphology plays a pivotal role in shaping both air quality and thermal environments, yet their interactions remain insufficiently understood, particularly across different seasons. This study investigates the mediating role of land surface temperature (LST) in the relationship between impervious surface-based landscape metrics and PM2.5 concentration, using Wuhan, China, as a case study. Drawing on remote sensing data from the year of 2023 and 2024, this constructed seasonal mediation models to explore how impervious surface-based landscape metrics influence PM2.5 either directly or through thermal pathways. The findings reveal that certain impervious surface-based landscape metrics features can either amplify or mitigate pollution levels by altering the local thermal environment, while PM2.5 itself also exerts feedback on surface temperature. These insights underscore the dual regulatory role of urban form and pollution in shaping urban climates and highlight the seasonal complexity of spatial interventions for sustainable urban governance. The results contribute to a deeper understanding of cross-domain interactions in urban systems, offering a foundation for climate-responsive and pollution