Date of Award


Degree Type


Degree Name

Master of Science (MS)




Some species introduced into new regions have the potential to greatly impact native diversity and ecosystem functioning. The invasive hybrid cattail, Typha X glauca, has established in wetlands across the Great Lakes region decreasing native plant diversity and altering soil and microsite characteristics. We utilized 80 years of historical aerial photographs from the Illinois Beach State Park wetland complex to map the spread and determine the age of T. X glauca stands. Floristic, edaphic, and environmental data were collected from plots across an invasion-age gradient to determine the impacts of T. X glauca and time since invasion on environmental variables. We also investigated the effect that T. X glauca has on the overall quantity of denitrification and the quality of the gases produced (N2 vs. N2O). As T. X glauca produces large quantities of biomass in the form of litter, we hypothesized that invasions will cause a decrease in water levels due to several decades of T. X glauca litter deposition and a subsequent reduction in the quantity and quality of denitrification. We found time since invasion to be an important component of T. X glauca invasions as it was strongly correlated with the ecological effects of Typha, including increases in litter mass and soil organic depth and decreases in plant diversity. However, T. X glauca had no significant impacts on total denitrification or denitrification quality.

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Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 License.