Examining regulating ecosystem service provision by brownfield and park typologies and their urban distribution

Environmental hazards including air pollution, heat waves, and flooding are pressing issues in cities. In response, many cities are pledging to increase green infrastructure, adopting nature-based solutions for enhancing resilience through ecosystem service provision. At the same time, urban densification is increasingly considered necessary to limit urban sprawl, where redevelopment of brownfield is often promoted as an alternative to development of greenbelt land. Consequently, while the drive to install additional green infrastructure is intensifying, the synchronous loss of brownfield vegetation may result in unintentional net losses. It is therefore essential to evaluate brownfield’s contribution to ecosystem service provision. Here we present a comparative analysis of the regulating ecosystem services provided by brownfield and park trees in Greater Manchester, UK. Parks were selected as a comparator as they represent the most abundant and widely distributed types of open green space, and typically contain a high proportion of trees. Ecosystem service provision was evaluated across statistically defined typologies of twenty-six brownfield and twelve park types (varying in terms of landscape metrics, land, and canopy cover) using i-Tree Canopy. In terms of carbon storage brownfield (3194ha) provided an estimated 52,765t of carbon storage and annual carbon sequestration of 2,101t/y, for parks (4128ha), 143,064t of carbon storage, carbon sequestration of 5,696t/y. Annual air pollution removal is estimated at 313t/y of air pollution removal for brownfields, and 849t/y for parks. Avoided surface water runoff is estimated at 135,018m3/y for brownfields and 366,280m3/y for parks. In densely built areas, brownfields provided approximately five times more regulating ecosystem services than parks, and several types of vegetated brownfield provided more regulating ecosystem services than many types of park. We conclude that brownfield is an important component of green infrastructure, where this knowledge is critical to inform planning and management, prevent loss of ecosystem services, and identify where strategic greening of brownfield may address inequities in existing green infrastructure.