Dr. Claudia Wagner-Riddle from the University of Guelph will be presenting a talk as part of the Ecohydrology Seminar Series on May 29th.
Agricultural soils are a significant anthropogenic source of nitrous oxide (N2O), a trace gas that contributes to the enhanced greenhouse effect and stratospheric ozone destruction. The complex interplay of microbiological processes and soil conditions regulates N2O dynamics in the soil profile, and when N2O is released from the soil surface. Management practices (e.g. inorganic nitrogen addition) and weather (e.g. severity of winter freezing) are external factors driving this interaction, ultimately determining the magnitude of N2O production and large temporal variability in emission. We have conducted several studies deploying a micrometeorological technique to characterize this temporal variability with the objective of improving our understanding of what drives N2O fluxes and design management practices for mitigation. Surface N2O fluxes have been linked to soil processes through molecular techniques and use of stable isotopes. An overview of past research findings and on-going work will be given, including recent research using large field-scale soil lysimeters instrumented for greenhouse gas emissions studies.