Vacant lot soil degradation and mowing frequency shape communities of belowground invertebrates and urban spontaneous vegetation

Abstract

Vacant land in legacy cities is increasingly recognized as a resource to support biodiversity and improve the quality of life for residents. However, the capacity for vacant lot parcels to provide these benefits is influenced by current management practices and landscape legacies of urbanization, which typically results in degraded soil quality. The role of soil quality in supporting urban biodiversity and ecosystem functions is often overlooked when developing sustainable urban planning initiatives. This study investigated how soil physical and chemical properties influenced the community of urban spontaneous vegetation and soil invertebrates found within vacant lots mowed monthly or annually in Cleveland, Ohio, USA. We found that soil chemical and physical properties were strong predictors of soil-dwelling invertebrates, as vacant lots highly contaminated with heavy metals had simplified communities. Moreover, increased mowing frequency resulted in greater biomass and blooms of urban spontaneous forbs. Importantly, vacant lots dominated by urban spontaneous forbs and high bloom abundances also were contaminated with heavy metals, with implications for herbivores and pollinators using these resources. Our findings indicate that conservation initiatives must consider landscape legacies from industrial activity and local habitat management practices in order to support above and belowground habitat quality of greenspaces in urban ecosystems. Understanding how soil degradation impacts habitat quality and the delivery of ecosystem services from vacant land is essential for legacy cities to maximize their environmental benefits.