Reactive soil nitrogen has an impact on ecosystem health and on the exchange of nitrogen between the surface and atmosphere. Although the turnover time of ammonium and nitrate in soils has been shown to be on the order of a day, there is a lack of short time scale measurements of these compounds in the environment. This project aims to address this lack by examining temporal trends of nitrate, ammonium, and soil acidity over daily to weekly timescales. Simultaneous measurements of gas and particle phase concentrations of nitrogen species as well as environmental! variables such as rain and temperature will improve our understanding of the processes involved and their impacts on air quality and ecosystem health.
Additional Scientific Information
Soil samples will be taken every 6 hours over a period of two weeks on an unfertilized short-grass field site. Samples will be extracted on-site and analyzed at Lash Miller Chemical Laboratories by Ion Chromatography. Continuous measurements of air and soil moisture and temperature will be made throughout the study, as well as simultaneous hourly averaged measurements of inorganic species in the gas and particle phases by Ambient Ion Monitor-Ion Chromatography. This study will provide insight into the role of reactive soil nitrogen pools on surface-atmosphere exchange of nitrogen species as well as informing our understanding of the variability in soil nitrogen, and the factors that drive it.
Principal Investigator: Jennifer Murphy
Researcher(s): Greg Wentworth, Alex Tevlin