Baltimore Ecosystem Study Institute of Ecosystem Studies

2014 BES Annual Meeting Presentation and Poster Abstracts

Changing trajectories in urban forest patches: Ecological restoration in New York City parks
Johnson, Lea R.
Co-Authors: Steven N. Handel

Abstract: Forest remnants in urban parks are disproportionately important to both local biodiversity and human well-being, and municipalities are increasingly turning to ecological restoration of urban forests to provide multiple ecosystem services. In New York City, efforts to restore forests have now been ongoing for 20 years. To test whether restoration treatments resulted in desired long-term changes, we sampled vegetation in 30 sites in 3 large public parks that had been invaded by non-native woody plants and were restored 1988-1993, and 30 sites in 3 large parks that were similarly invaded but had not been restored in 2010. Data show that the restoration treatment achieved its central goals: after 15-20 years, invasive species removal followed by native tree planting resulted in persistent structural and compositional shifts, lower invasive species abundance, a more complex forest structure, and greater native tree recruitment. Together, these findings indicate that successional trajectories of vegetation development have diverged between restored forests and invaded forests that were not restored. However, the data also suggest that future composition of these urban forest patches will be novel assemblages. The trajectories of these new associations will develop in forest patches subject to urban conditions. Models of ecological restoration developed in more pristine environments must therefore be modified for use in cities. Anticipating urban disturbances and ecological succession, realistic, flexible targets can be developed to preserve and enhance urban biodiversity for both short-term benefits and long-term sustainability.