Baltimore Ecosystem Study Cary Institute of Ecosystem Studies

2012 BES Annual Meeting Presentation and Poster Abstracts

Legacies of human management drive patterns of plant species diversity across scales
Johnson, Anna
Co-Authors: Erica Tauzer, Christopher M. Swan

Abstract: While we have a robust understanding of patterns of species diversity in urban systems, we know relatively little about the processes that drive these patterns. Herbaceous plant surveys were conducted in Baltimore, MD, during the summer of 2009 in habitat patches in vacant lots that were hypothesized to have varying levels of human management. These lots were resurveyed during the summer of 2012, and additional environmental variables were collected. Using a metacommunity framework, we hypothesize that humans influence both the local and regional processes that drive plant community assembly, and that this results in patterns of species diversity and composition that are not well explained by models that do not take human impacts into account. We ask 1) does the spatial partitioning of species diversity vary between management groups? And 2) do communities in different management groups also show divergent patterns of phylogenetic diversity? We found significant differences in the spatial partitioning of diversity between the building footprints of vacant lots, representing low selective management, and remnant garden sections of vacant lots, representing a legacy of high selective management. Remnant gardens showed similar local diversity to the building footprint sections but significantly higher turnover between the remnant garden patches. We also found greater phylogenetic diversity in remnant gardens than in building footprint sections, which indicates that even in habitats with relatively depauperate species pools, phylogenetic analyses may give valuable insight into the relative importance of competition, environmental filtering and dispersal in driving patterns of species coexistence.