According to this article, invasive plant species pose a threat to many ecosystems, including wetlands. Invasive plant species have been known to outcompete and take over native plant communities, reduce the amount of different native plants in an area, and alter nitrogen and carbon cycles within the environment by altering the microorganism community (microbiome). This paper focuses on the chemical and physical compositions as well as the soil microbial communities of the Cheboygan March, a freshwater wetland, in Michigan. The marsh was infested by an invasive hybrid species of plant called TyphaÃ—glauca about 30-40 years ago. Because the study area was divided into 3 stages (native plants, transitional, and only TyphaÃ—glauca), the researchers were able to establish a gradient of infestation, chemical composition, and microbial community differences. They ran chemical composition tests to determine whether this invasive plant species was altering the sediment nutrient content. To determine whether or not the microbial community composition was being altered, they ran sediment samples through DNA sequencing and Polymerase Chain Reaction (PCR: used to amplify certain sections of DNA). They also ran functional gene analysis on the samples to see if microbes were using genes associated with nitrogen uptake and cycling, an important nutrient in the environment. Overall, they found that the microbial community composition was significantly different between the native plant area and the TyphaÃ—glauca area. There were more species of bacteria in the TyphaÃ—glauca area than the native plant section. Chemically, they found a significant increase in soluble nutrients within the TyphaÃ—glauca section. They also found that the abundance of one important gene used for nitrogen cycling by microbes was higher in the TyphaÃ—glauca section than in the native area. This study proved that invasive plant species have a significant impact on sediment chemical and microbial characteristics. Invasive plants may hinder the ability for natural wetlands to rid the environment of excess nutrients, thus altering the nutrient cycles for surrounding ecosystems, but more research must be compiled to support this statement.
Citation: Angeloni, N. L., Jankowski, K. J., Tuchman, N. C., & Kelly, J. J. (2006). Effects of an invasive cattail species (TyphaÃ— glauca) on sediment nitrogen and microbial community composition in a freshwater wetland. FEMS microbiology letters, 263(1), 86-92.