Nitrous Oxide Emissions in Response to ESN and Urea Application in a No-Till Barley Cropping System

ABSTRACT

We investigated the effect of environmentally smart nitrogen (ESN) fertilizer on nitrous oxide (N₂O) emissions under no-till barley (Hordeum vulgare L.) production over 3 years at three sites in Alberta, Canada. Treatments included two barley cultivars, with ESN and urea applied at 1× and 1.5× the recommended rate, and herbicide at 50% and 100% of registered in-crop rates. Cumulative N₂O emissions over the growing season were low (0.11 to 1.32 kg nitrogen (N) per hectare or 0.05–0.22 g N kg⁻¹ grain yield), and not affected by barley cultivars or herbicide rates in all nine site-years, nor by fertilizer type or rate in seven out of nine site-years. However, average N₂O emissions from ESN were 15% lower (P = 0.05) than urea across all site-years. Our results suggest ESN could play a role in reducing N₂O emissions, but the reduction will depend on rainfall events and crop N utilization.

KEYWORDS:

• Cereal
• environmentally smart nitrogen
• nitrous oxide emissions
• polymer-coated urea
• semi-arid climate
• semi-humid climate
• urea

Acknowledgment

The authors thank Greg Travis, Brett Hill, Pam Caffyn, Jamie Walker, Chad Herbert, Patty Reid, Greg Semach, Irene Murray, and Amy Rolfson for their technical support in field sampling and laboratory analysis.

Funding

Funding for this research was provided by Agriculture and Agri-Food Canada. This is LRC contribution number 38712014.

Additional information

Funding

Funding for this research was provided by Agriculture and Agri-Food Canada. This is LRC contribution number 38712014.