The influences of physiology, allocation, and natural enemies on the success and failure of exotic woody vines in Northeastern forests.

摘要

Woody vines are known to play a vital role in forest ecosystems and yet they remain one of the most understudied groups of vascular plants. In this dissertation, I investigate the influence of growth, biomass allocation, physiology, and response to natural enemies in determining the success of invasive species and in particular, temperate invasive vines on Long Island, NY. In order to identify characteristics that may be essential for success, I use a novel approach of experimentally comparing related native and exotic invasive vines with their exotic relatives that are present on Long Island but have failed to invade. Using greenhouse and field experiments, I test whether invasive vines possess physiological and ecological traits that favor efficient use of light and nutrients. I also explore how tolerance and resistance to herbivory may influence invasion success.; A review of the literature suggests that most invasive species have fast growth rates relative to natives. Certain conditions, such as high nutrient availability and high light, favor the growth of invasive species. In experimental work, similar patterns emerged for woody vines. There was a large variation among vines in response to light in a greenhouse experiment, but I find invasive vines generally have higher growth rates and higher photosynthetic rates than exotic non-invasive vines. In a field experiment, I find that the response to light and growth rates were site and species dependent. However, overall invasive species grew faster than natives in the sun and growth was similar in the shade. All vines responded similarly to a transplant experiment, suggesting that faster response to gap formation cannot explain the success of invasives.; Vines were susceptible to mammal and insect herbivores and mammals greatly reduced the growth and survival of all vines and there was no clear difference in resistance among vines. I find, however, that tolerance did vary among invasive, exotic, and native vines with native vines having lower tolerance than introduced vines. Ultimately, this research will add to our understanding of the ecology of temperate vines as well as the ecology of biological invasions.