Connecting Disadvantaged Communities with Green Space: Towards Better Policy Design

Recent advancements in mobile sensing technologies and big data analytics have spurred a "mobility turn" in green space exposure studies, emphasizing the importance of human movement and visitation patterns. However, existing environmental justice (EJ) literature on green spaces predominantly highlights inequities in fixed-location exposures or spatial access rather than accounting for how people use and interact with green spaces. Leveraging large-scale human mobility data collected from mobile phones, this dissertation sheds light on the crucial but underexplored dimension of use or visitation-related inequity in EJ. It employs geospatial analyses and quasi-experimental methods to examine the influence of COVID-19 and transportation infrastructures on green space visitation patterns in Phoenix, Arizona. The first essay analyzes the effect of COVID-19 pandemic on Phoenix residents’ visits to parks in the United States. During the early stages of the pandemic, when strict mobility restrictions (e.g., stay-at-home orders) were in effect, park visits decreased by 40.2% compared to 2019 levels. Notably, the reduction was significantly higher in lower-income communities. The second essay examines how highways interrupt visits to nearby parks within walking distance. In 2019, Phoenix residents made 55% fewer visits to local parks when their trips were interrupted by highways compared to trips to parks without such interruptions. The third essay investigates the impact of public transportation on visits to South Mountain in Phoenix. By comparing 2019 visit frequencies between neighborhoods connected to the mountain’s trailheads by transit and those with similar characteristics but lacking such connections, the findings show that public transportation increases visits, especially in neighborhoods without nearby parks. Collectively, this dissertation highlights the complex challenges that arise when policies in one domain—such as public health emergencies or transportation planning—unintentionally have adverse effects on another, particularly in the context of environmental justice related to green spaces. Therefore, it calls for adaptive policy solutions that modify or enhance existing policies to address unintended cross-domain impacts, simultaneously advancing public health, infrastructure development, and environmental justice to foster sustainable and equitable urban environments.