PARENT SESSION
Poster Session # 7: Restoration, Resource Management, and Conservation.
Monday, August 4 Presentation from 5:00 PM to 6:30 PM. SITCC Exhibit Hall B.
Can we design urban forest corridors to resist invasion by exotic plant species?
Vidra, Rebecca1, Hess, George1, Shear, Theodore1, 1 North Carolina State University, Raleigh, NC
ABSTRACT- Management and restoration of native ecological communities would be greatly enhanced with knowledge of characteristics that make them resistant to exotic species invasion. This is particularly important in urban areas, where remnant habitats provide important ecological functions but are often degraded by invasive species. While many studies have addressed the influences of disturbance, resource availability, and species richness on invasibility, certain structural features of habitat patches are also thought to control patterns of exotic species invasion. For example, larger patches of intact habitat are thought to be less susceptible to invasion than small isolated fragments with high edge to area ratios. The character of the surrounding landscape may also affect invasion dynamics. We studied the influence of landscape structure and context on the invasion of forested riparian corridors. Specifically, we examined the relationship between the distribution of exotic plants in forested greenways and the nature of the surrounding landscape, including width and surrounding development density. We used a modified belt transect approach to record presence, frequency, and percent cover for 16 invasive exotic plant species in each corridor. The frequency of occurrence and mean percent cover of four common species, Microstegium vimineum, Ligustrum sinense, and Lonicera japonica, were significantly negatively correlated with corridor width. Several species were positively correlated with development density, but an interaction between width and context warrants further exploration. Here we present these results, with special attention to the distribution of M. vimineum, a pervasive exotic annual grass in these riparian corridors. We also examine the within-site variability in exotic species presence and abundance to account for local-scale characteristics that may promote invasion. The results of this study can guide forest corridor protection and restoration in urbanizing areas, where there are many sources of invasive propagules and few opportunities for preservation.
Key words: landscape structure, Microstegium vimineum, exotic species, riparian corridors