Temporal and Spatial Trends in the Abundance of Functional Denitrification Genes and Observed Soil Moisture and Potential Denitrification Rates.

University of Minnesota M.S. thesis. September 2016. Major: Water Resources Science. Advisor: Michael Sadowsky. 1 computer file (PDF); vi, 131 pages.In an attempt to identify a genetic basis for observed denitrification rates, denitrification functional genes nirS, nirK, narG, cnorBB, nosZ1, and nosZ3 were quantified using qPCR of DNA extracted from soils and sediments taken from agricultural runoff ditches in the Seven Mile Creek watershed. Gene copy numbers were analyzed with respect to both spatial and temporal scales, as well as compared to soil moisture levels and potential denitrification as determined by the acetylene inhibition method. Results of this study suggest a link between soil moisture and potential denitrification, although more formal relationships could be determined. Discriminant analyses also show similarities in genetic composition of analyzed samples over both spatial and temporal scales