Natural outdoor environment, neighbourhood social cohesion and mental health: Using multilevel structural equation modelling, streetscape and remote-sensing metrics

Although a growing body of research has explored the relationship between neighbourhood natural outdoor environments and mental health, most studies have measured neighbourhood natural outdoor environments from a bird's-eye perspective, rather than measuring the visual experience of green and blue space that individuals have at the ground level. In addition, few studies have investigated how different dimensions of neighbourhood social cohesion mediates the relationship between the natural outdoor environment and mental health. To bridge these gaps, we examined the relationship between neighbourhood natural outdoor environments and individuals' mental health in Guangzhou, China, using a combination of questionnaire survey data, streetscape and remote-sensing metrics, and multilevel structural equation modelling. More particularly, this study explored the mediating effects of three dimensions of neighbourhood social cohesion (i.e. neighbourhood attachment, neighbourly interaction, and community participation). The results indicate that neighbourhood green space and blue space are both positively associated with individuals' mental health. Neighbourhood street greenery exerts beneficial effects on mental health, directly by its visual effect, and indirectly by improving neighbourhood attachment and community participation. Neighbourhood street-view blue space and surrounding green (blue) space also has a positive influence on mental health, but it does so in a direct manner only. This study contributes to our knowledge by estimating the mediating impacts of three dimensions of neighbourhood social cohesion and applying both streetscape and remote-sensing metrics of visible green space and blue space within neighbourhoods.