Evaluating the Use of Enhanced Efficiency Nitrogen Fertilizer Products to Reduce Nitrous Oxide Emissions Under Irrigated and Non-Irrigated Conditions.

Title: Evaluating the Use of Enhanced Efficiency Nitrogen Fertilizer Products to Reduce Nitrous Oxide Emissions under Irrigated and Non-Irrigated Conditions

Authors: Cheyne Ogilvie¹, Reynald Lemke², Fran Walley¹, and Richard Farrell¹

Affiliations for each author:  ¹University of Saskatchewan, Department of Soil Science, Saskatoon, SK
²Agriculture & Agri-Food Canada, Saskatoon Research Centre, Saskatoon, SK

ABSTRACT

Nitrogen fertilizers added to agricultural field crops are a significant source of nitrous oxide (N₂O) emissions from Canadian soils. The development and implementation of new technologies and management practices is critical to improving environmental stewardship, climate change initiatives and agronomic efficiency. Enhanced Efficiency Fertilizers (EEFs) reduce environmental losses that contribute to greenhouse gas (GHG) emissions and allow the release of nutrients to occur in tandem with in-season crop uptake. This study includes two sites, an irrigated and a non-irrigated site, located in the Brown Soil Zone near Broderick, Saskatchewan, Canada. Over the first of two seasons of this research project, N₂O emissions were quantified in plots containing an unfertilized check, urea, anhydrous ammonia, a polymer-coated urea (ESN), two nitrification inhibitors (eNtrench & N-Serve), a urease inhibitor (Limus) and a dual (nitrification + urease) inhibitor (SuperU). N₂O emissions were measured using non-steady state vented chambers that were placed in the on-band and off-band (between fertilizer band) positions. Samples were returned to the GHG Analysis Laboratory at the University of Saskatchewan and analyzed using standard gas chromatography techniques. PRS™ Probes were placed on the spring applied fertilizer bands for 3 day intervals for 30 days after fertilization to assess nutrient release rate. Preliminary results suggest that N₂O emissions are higher on the irrigated site and that there are greater differences between treatments on the non-irrigated site. GHG emission and fertilizer efficiency results will be presented and discussed.