Many cities, especially in what is considered the U.S. Rust Belt, have experienced long-term declines in population. Dramatic population loss has the potential to alter urban social-ecological patterns and as a result environmental justice outcomes. Housing vacancy, in particular, is intricately tied to changes in both economic and environmental systems. Vacancy may drive increases in volunteer vegetation, creating a potential disamenity and artificially producing outcomes that suggest more equitable relationships between greenness and social variables. Toledo is a shrinking city in northwestern Ohio whose population peaked in 1970 at 383,818 before declining by more than 100,000 people at present. This resulted in high rates of vacant housing. Of importance to vegetation cover, Toledo, like most U.S. shrinking cities, has used demolition to manage blighted vacant houses. We examined satellite imagery from 1980 and 2014 to assess changes in NDVI (normalized difference vegetation index, i.e., greenness/vegetation cover) and its association with housing vacancy rates according the US Decennial Census Data from 1980 and 2010 to determine whether the relationship between greenness as an environmental outcome and housing vacancy as a socio-economic outcome changed from early on to several decades into a major population decline.
Results/Conclusions
In our assessment of data from 1980 and 2014 we observed a weakening relationship between vacancy and greenness. Specifically, there was a significant negative relationship between vacancy rates and greenness in 1980; whereas, in 2014 there was no relationship. As vacancy is highly correlated with vulnerable populations, this changing trajectory has implications for environmental justice outcomes. Our results highlight the limitation of using vegetation abundance as an indicator of environmental amenities, and suggest this limitation is more problematic in shrinking cities. Thus, more nuanced approaches to evaluating environmental justice and equity outcomes are needed.