Date Approved


Degree Type

Open Access Senior Honors Thesis

Department or School


First Advisor

Dr. Kristin Judd

Second Advisor

Dr. Daniel Clemans

Third Advisor

Dr. Gary Hannan


Microbial populations have very important roles in wetlands because they are highly involved in nutrient cycling processes essential to health of the ecosystem. This study examines the changes that occur in bacterial and methanogen abundance in the soil in wetlands that have been taken over by the invasive reed Phragmites australis compared to soils that are inhabited by cattail species (Typha). To measure microbial abundance, soil samples were collected from a freshwater marsh, DNA was extracted from the soil, and bacterial DNA was amplified using primers specific to the Eubacterial l6s rRNA and methanogen mcrA genes, and subsequently analyzed using qPC R. The results indicate that there is no difference between the abundance of bacteria or methanogens in Phragmites and Typha soils (P < 0.05). Although P. australis does not appear to alter the overall abundance of bacteria or methanogens, future studies focusing on microbial community composition, gene expression, and microbial activity in wetland soils invaded by Phragmites would help determine whether the invasion of wetlands by Phragmites has led to changes in wetland soil microbial communities and their function in the environment.