Date of Completion


Embargo Period



Robin L. Chazdon, Daniel L. Civco

Field of Study

Ecology and Evolutionary Biology


Master of Science

Open Access

Open Access


Humans are the most important drivers of invasive species introduction and natural habitat transformation globally. Ecological differences between areas of dense human habitation and minimally managed natural habitats were explored across an urban-to-rural gradient of land use in southern New England. These differences were examined through presence/absence and leaf functional traits for a set of invasive species; and urban and rural environmental conditions. Some species were more restricted to particular sites than others along the urbanization gradient, based on introduction history and habitat preference. A priori urban-classified species showed trait values associated with drought tolerance, including higher LWR, greater leaf thickness, higher LDMC and lower SLA. Finally, urban habitats were found to be significantly different from rural habitats. Urban soils were more alkaline, and had higher lead concentrations and sand content than rural soils. Urban habitats had more open canopies, impervious surface, patch forests, and induced edge habitats than rural habitats. Our findings suggest that urban environmental conditions contribute to an “urban drought island” syndrome and will favor species capable of tolerating drought.

Major Advisor

John A. Silander