Anthropogenic climate change, land use changes, and global human-mediated transport of exotic species results a loss of regional distinctiveness, a phenomenon known as biotic homogenization. One potential driver of biotic homogenization is urbanization, which is associated with increases in disturbance frequency and intensity, habitat fragmentation, and the introduction of non-native species. Urban areas have been treated as uniform spaces when in actuality cities are composed of a broad diversity of land uses. The high prevalence of vacant properties in shrinking cities like Cleveland, Ohio make understanding the ecology of these spaces critical. This study aims to investigate whether vacant lot plant and soil microbial communities are more homogenized with increasing intensity of urbanization. Plant community abundance and diversity were assessed in vacant lots in Northeast Ohio to examine the effects of urbanization. The intensity of urbanization of sites ranged from urban (Cleveland), suburban (Lake County) and exurban (Holden Arboretum). Plant surveys were conducted in the summers of 2016 and 2019, using randomly placed one-meter quadrats to assess presence and percent cover data of plant species, and the soil microbial community was sampled. Taxonomic and functional diversity analyses were performed comparing plant communities both between and within site types.
Results/Conclusions
The mean plant richness was different between vacant lot sites (ANOVA, F (2,9)=7.4, p=0.013), decreasing with increasing intensity of urbanization. A post hoc Tukey’s test showed that exurban and urban sites differed significantly (p=0.011); the suburban group was not significantly different from the other two groups, generally falling in the intermediate range. These results suggest a relationship between urbanization and homogenization of plant communities in vacant lots. Homogenization of vegetative communities could have cascading effects throughout the rest of the ecosystem. Ongoing work examines the soil microbial homogenization in these systems. Improving our understanding of the ecological impacts of anthropogenic activities can help humans minimize our impacts on ecosystem functioning in the future.