Urban greenspace access: leveraging a novel metric to examine greenspace inequities and maternal mental health within Minneapolis and St. Paul, Minnesota

Abstract

Urban greenspaces—human-made or naturally occurring areas that predominantly feature vegetation—have spurred an increase in local, federal, and international interest in promoting and enhancing public and environmental health. Urban greenspaces offer a range of potential benefits, including urban heat island and flood mitigation, carbon storage and sequestration, reduced air and noise pollution, increased physical activity, enhanced social cohesion and cultural exchange, and improved psychological and physiological health. These potential benefits position greenspaces as a possible cost-effective and efficient solution to urban challenges related to inadequate physical activity, poor mental health and well-being, and environmental concerns. Despite the growing recognition of the potential health benefits conferred by greenspaces, significant knowledge gaps persist. Advancing scientific knowledge necessitates improved quantification of greenspace access, addressing the legacy of structural racism and greenspace inequities, and investigating the impact of greenspaces on maternal mental health. This dissertation addresses these gaps through three interrelated studies conducted in Minneapolis and St. Paul, Minnesota. Manuscript 1 developed the novel Urban Greenspace Access Score (UGAS), a composite metric that measures greenspace access based on three constructs: 1. Surrounding vegetation, 2. Proximity to and quantity of public greenspaces, and 3. Proximity to and quantity of semipublic greenspaces. UGAS was compared to four commonly used greenspace measures. Derived at a 100-meter resolution, UGAS was used to map greenspace access across Minneapolis and St. Paul and identify disparities in greenspace access. Data sources included the 2020 Metro Collaborative Parks, 2020 Generalized Land Use, US Department of Agriculture 2021 National Agriculture Imagery Program, and the 2015 Twin Cities Metropolitan Area Urban Tree Canopy Assessment. Manuscript 2 examined historical racialized practices and contemporary greenspace access inequities in Minneapolis and St. Paul. Specifically, this study examined the association between the intensity of racial covenants, Home Owners’ Loan Corporation (HOLC) neighborhood grades, neighborhood race-ethnicity composition, and contemporary greenspace access. Digitized racial covenant data were obtained from Mapping Prejudice, HOLC neighborhood grades were obtained from University of Richmond’s Digital Scholarship Lab, and 2020 US Census demographic data were obtained from the Integrated Public Use Microdata Series. Manuscript 3 investigated the association between greenspace access and postpartum depression among mothers in Minneapolis who had a singleton live birth between 2019 and 2022 using electronic health records from M Health Fairview. Post hoc analyses explored the associations between greenspace access, gestational age and preterm birth, highlighting broader implications for maternal and child health. Overall, this dissertation highlights the critical role of urban greenspaces in advancing health equity. The results provide evidence of greenspace deserts in Minneapolis and St. Paul, the enduring association between historical racialized policies and contemporary greenspace inequities, and a potential protective association between greenspace access and postpartum depression. These findings underscore the need for collaborative efforts between communities and urban planners to co-design and implement initiatives that ensure equitable greenspace access, ultimately improving public health. Our actions regarding urban greenspaces will arguably have a significant influence on the future health and well-being of our communities.