Understanding the potential loss and inequities of green space distribution with urban densification

Urban population growth is leading to growing concerns about land use change, green infrastructure, and the loss of beneficial ecosystem services. Human and environmental health is supported by services such as climate regulation, air filtration, and flood mitigation. However, maintaining these services within cities requires the preservation and equitable distribution of green infrastructure near where people live. Sydney, Australia, where the population is expected to grow from 4.3 million to 5.6 million by 2031, is undergoing an urban transformation. This study investigates the spatial distribution of green infrastructure within Sydney to determine how patterns of green infrastructure vary according to land use, residential density, and socio-economic variation. More than half of urban Sydney is comprised of residential land use, representing the single largest contribution to Sydney's green infrastructure. Two types of green infrastructure are examined in this study, public green space represented by parkland area and tree canopy cover and private green space represented by residential area and tree canopy cover. Results show that with greater dwelling density, both types of green infrastructure decrease. Availability of private versus public green infrastructure, however, differs according to socio-economic advantage. Suburbs of higher socio-economic advantage have significantly more private green cover, but slightly less public green cover than suburbs of greater disadvantage. These findings highlight that urban densification can lead to a general loss of two important reservoirs of urban green infrastructure (public parkland and residential tree cover). Disadvantaged communities may have a greater reliance on public green infrastructure in the form of parkland due to a lack of private residential tree cover. (C) 2015 Elsevier GmbH. All rights reserved.