Patterns of exotic plants in relation to anthropogenic edges within urban forest remnants
Article first published online: 3 APR 2012
© 2012 International Association for Vegetation Science
Applied Vegetation Science
Volume 15, Issue 4, pages 525–535, October 2012
How to Cite
LaPaix, R., Harper, K., Freedman, B. (2012), Patterns of exotic plants in relation to anthropogenic edges within urban forest remnants. Applied Vegetation Science, 15: 525–535. doi: 10.1111/j.1654-109X.2012.01195.x
- Issue published online: 4 SEP 2012
- Article first published online: 3 APR 2012
- Manuscript Accepted: 14 FEB 2012
- Manuscript Received: 6 DEC 2011
- Natural Sciences and Engineering Research Council of Canada (NSERC) and Dalhousie University
- Dr. Patrick Lett Fund
- discovery research NSERC
- Edge influence;
- Edge interaction;
- Exotic species;
- Forest boundaries;
- Urban parks
How is the abundance of exotic plants within urban forest remnants influenced by distance to the edges of forest boundaries and recreational trails?
Halifax, Nova Scotia, Canada.
Gradients in the cover of exotic plants, as well as the richness of exotic and native vascular species, were examined as a function of distance from anthropogenic forest boundaries and recreational trails. Plants were sampled in 2 m × 10 m and 10 m × 10 m plots distributed among 11 urban forest remnants. Randomization tests were used to quantify the distance of edge influence from both forest boundaries and trails, and to determine if there was an interaction between them.
The cover and richness of exotic plants and richness of native species decreased with increasing distance from forest boundaries and trails. Edge influences extended to distances of ca. 50 and 3 m for forest boundaries and trails, respectively, and were stronger for measures of understorey than of overstorey vegetation. Vegetation was simultaneously influenced by both edge types such that exotic cover and richness were higher when in close proximity to two edges than when subject to either edge alone (i.e. a positive interaction).
It is important to consider the influence of edges in the design and management of forest remnants to improve the ability to conserve native biodiversity within cities. Results from this study may be used to guide the design of such systems, particularly by suggesting appropriately sized patches and trail densities.