Comparing nitrous oxide producing and consuming communities in the rhizospheres of Maine native and invasive wetland plants
Document Type
Oral Presentation
Department
Biological Sciences
Abstract
Phragmites australis is an invasive plant to Maine wetlands that affects the ecosystem services wetlands can provide. While its efficiency at nutrient uptake makes P. australis an attractive candidate for bioremediation of nitrogen polluted waters, it is not clear how P. australis alters the soil microbial communities that perform nitrogen cycling processes. Specifically, soil microbes control transformations in the denitrification pathway, including the production or consumption of nitrous oxide, a potent greenhouse gas. Since different plants harbor unique root microbiomes, the rhizosphere communities on P. australis and the native plant Spartina alterniflora were compared in molecular assays of the extracted DNA and RNA from root samples collected at the Wells National Estuarine Research Reserve. The ratios of nitrous oxide producing (nirK and nirS) to consuming (nosZI and nosZII) genes were quantified by using quantitative PCR to determine gene abundance. The diversity and relative abundance of nosZII orthologs were determined using next generation sequencing to understand community structure. These results set a baseline for understanding how the spread of P. australis may alter biogeochemical cycling capacities of soil microbial communities as well as inform wetland plant management practices.
Comparing nitrous oxide producing and consuming communities in the rhizospheres of Maine native and invasive wetland plants
Phragmites australis is an invasive plant to Maine wetlands that affects the ecosystem services wetlands can provide. While its efficiency at nutrient uptake makes P. australis an attractive candidate for bioremediation of nitrogen polluted waters, it is not clear how P. australis alters the soil microbial communities that perform nitrogen cycling processes. Specifically, soil microbes control transformations in the denitrification pathway, including the production or consumption of nitrous oxide, a potent greenhouse gas. Since different plants harbor unique root microbiomes, the rhizosphere communities on P. australis and the native plant Spartina alterniflora were compared in molecular assays of the extracted DNA and RNA from root samples collected at the Wells National Estuarine Research Reserve. The ratios of nitrous oxide producing (nirK and nirS) to consuming (nosZI and nosZII) genes were quantified by using quantitative PCR to determine gene abundance. The diversity and relative abundance of nosZII orthologs were determined using next generation sequencing to understand community structure. These results set a baseline for understanding how the spread of P. australis may alter biogeochemical cycling capacities of soil microbial communities as well as inform wetland plant management practices.
