Greenspace morphology and mental well-being: a mobility-based study on urban stress and emotion

• We examine how greenspace morphology affects momentary stress and emotions. • Simpler and regular greenspace shapes reduce stress and enhance positive emotions. • Higher greenspace coverage was associated with lower stress levels. • Larger and continuous greenspace patches improved emotional well-being. • Spatial configuration modifies the psychological benefits of greenspace coverage. As urbanization continues to accelerate, urban greenspaces have become increasingly vital in supporting people’s mental well-being. While previous research has largely focused on static measures of greenspace quantity, less attention has been given to the dynamic nature of individual exposure and the specific morphological characteristics of greenspaces. This study addresses these gaps by integrating GPS tracking data with remote sensing imagery to examine how greenspace morphology affects momentary stress and emotions among 786 participants in Hong Kong. The findings reveal that greenspaces with simpler, more regular shapes significantly reduce momentary stress and enhance positive emotions. Higher greenspace coverage was consistently associated with lower stress levels, while larger, continuous greenspace patches had a distinct positive effect on emotional well-being. However, interaction analyses indicate that increased connectivity and aggregation of greenspaces can weaken the stress-reducing benefits of greenspace coverage. Additionally, in areas dominated by large greenspaces, the impact of coverage on stress reduction was insignificant, whereas larger average patch sizes were positively linked to momentary emotional improvements. These results highlight the complex interplay between greenspace morphology and mental health, underscoring the importance of incorporating dynamic exposure measures in future research. The study provides empirical insights for urban greenspace planning, suggesting that beyond simply expanding greenspace coverage, optimizing morphological characteristics—such as maintaining regular shapes and minimizing aggregation—can enhance the mental health benefits of urban green environments.