PARENT SESSION
Session #21: Current status of knowledge on invasive species: Theory and practice. Organized by: R. C. Anderson and W. R. Perry.
Thursday, August 9, 2001. Madison Ballroom B
What species and community information can be used to predict the outcome of invasion on communities?
Kaufman, Sylvan1, Bazzaz, Fakhri1, 1
ABSTRACT- Invasive plant species are unique in their ability to take over existing plant communities and modify their function. To do so, they must compete with existing species for resources or use resources which are not being used by the resident community. Studies of succession and crop-weed interactions have demonstrated that physiological traits, such as resource use efficiency, many life-history traits including phenology, growth characteristics, and reproduction, and relative rates of herbivory are important in competition. Studies comparing invasive and native species have generally shown that invasives leaf out earlier or hold their leaves longer than natives, that invasive plant architecture leads to greater light or nutrient capture, that invasive species have high fecundity, and that native plants suffer higher herbivory. The few studies comparing native and invasive species physiological traits have mixed results with some showing higher resource use efficiency in invasive species, and others showing no difference in efficiency. Communities are composed of native species with varying life histories. In some, a single species is dominant, and in others there are more equal abundances of several species. Using information on resource availability, herbivory, and the life history characteristics of native and invasive species in a community, it may be possible to find a few traits that are predictive of the outcome of competition between species and of community composition.
KEY WORDS: biological invasions, Alliaria petiolata, physiology, life history