Mayer, BernhardLam, Carmen2013-09-202013-11-122013-09-202013Lam, C. (2013). Tracing Nitrogen in the Pedosphere and Hydrosphere of Agricultural Plots near Lethbridge, Alberta using Isotopic Techniques (Master's thesis, University of Calgary, Calgary, Canada). Retrieved from https://prism.ucalgary.ca. doi:10.11575/PRISM/28494http://hdl.handle.net/11023/990The source(s) and fate of nitrogen in soils and in shallow groundwater beneath agricultural plots with different fertilizer amendments were determined using isotopic techniques for an experimental field located near Lethbridge, Alberta. Isotopic compositions of nitrogen and of oxygen were determined for soil total nitrogen, soil nitrate, and groundwater nitrate. Treatment differences and temporal trends in groundwater nitrate concentrations indicated that synthetic fertilizer and fixed nitrogen had an impact on groundwater nitrate. Isotopic analyses identified mineralization of soil organic matter as the main source of soil and groundwater nitrogen, whereas fertilizer, fixed nitrogen, and manure did not appear to have had a large direct contribution. This may have been due to alteration of the original isotopic source signals of fertilizer, fixed nitrogen, and manure by nitrogen transformation processes (nitrification and denitrification) during nitrogen cycling in the soil and groundwater. Denitrification occurred in the groundwater within the three-year study period.engUniversity of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission.GeochemistryAgriculturestable isotopesGroundwater nitrateNitrificationDenitrificationmaster thesis10.11575/PRISM/28494