Perceived green and blue space, perceived biodiversity, and depression: Empirical evidence from China based on...

Amid rapid urbanization, mental health challenges have become increasingly prominent, highlighting the need to understand how natural environments support psychological well-being. This study examined how perceptions of green and blue space influence depression, with perceived biodiversity emphasized as a potential mediator.

Cross-sectional study.

Data were obtained from the 2021 Chinese General Social Survey (CGSS). Ordered logistic regression was used to analyze the associations of perceived green and blue space with depression. Mediation analysis was further conducted to test whether perceived biodiversity exerted indirect effects on depression.

Both perceived green and blue space were significantly associated with lower levels of depression. Perceived biodiversity fully mediated the relationship between perceived green space quantity and depression, and partially mediated the effect of perceived blue space quality. In contrast, perceived green space quality and perceived blue space quantity exerted their effects primarily through direct pathways.

By integrating subjective perceptions of green and blue space with perceived biodiversity as a cultural ecosystem service, this study provides new insights into the mechanisms linking nature and mental health. The findings suggest that urban planning should prioritize high-quality and biodiverse green and blue infrastructure as part of broader strategies to enhance mental health in rapidly urbanizing societies.