Zayas-Costa and colleagues introduce political economy into the relationship between urban nature and mental health. Using Barcelona health and census data, they distinguish access to all green space, parks and greenways while analysing neighbourhood gentrification and socioeconomic position as modifying conditions. Only greenways show a significant association with better mental-health outcomes, and the distribution of benefit varies with neighbourhood trajectory. The paper is important precisely because it prevents green infrastructure from being treated as socially innocent. Environmental improvement occurs within housing markets, displacement pressures and uneven urban development, so a new green amenity can support health while simultaneously participating in processes that destabilise existing communities. Methodologically, the study layers environmental exposure with longitudinal neighbourhood change rather than analysing spatial qualities in isolation. Its wider bridge reaches environmental justice and critical urbanism: health-supportive design must be evaluated not only by what it introduces into a place, but by who can remain, belong and benefit after transformation.
