Grant: Research Tools and Instruments - Category 1 (<$150,000)

Nitrous oxide (N2O) is a potent greenhouse gas, having a global warming potential of approximately 300 times that of CO2.  N2O is steadily increasing in the atmosphere, however the sources are not well known. Rivers are supersaturated with N2O but emissions from Canadian rivers have not been measured. Agricultural soils amended with fertilizers or manure emit N2O.  Our research uses ratios of stable isotopes (18O/16O and 15N/14N) to separate the two main processes producing N2O, nitrification and denitrification, in both forested and agricultural catchments.  Isotopic analysis of N2O can also be used to distinguish N2O from different anthropogenic sources, such as agriculture and sewage treatment plants.   CH4, another important greenhouse gas, is an important product of carbon cycling in landfills, wetlands and groundwater. Isotope analysis on low level CH4 opens new possibilities for understanding the sources and processes affecting CH4 concentrations in environments impacted by landfills, coal deposits and organic contaminants. A continuous flow isotope ratio mass spectrometer coupled with a gas concentrator will permit the analysis of N2O (18O/16O and 15N/14N) at trace to atmospheric levels.  The equipment will be immediately and heavily used by graduate and undergraduate students in scientific research on N2O and CH4.  The magnitude of N2O and CH4 fluxes and a better understanding of the factors that affect these greenhouse gas emissions are key components in watershed management and are needed to help Canada meet its reporting commitments under the United Nations Framework for Climate Change Convention and the Kyoto Protocol.