Greenhouse gas emissions from beef cattle pen surfaces in North Dakota

Abstract

There is a global interest to quantify and mitigate greenhouse gas (GHG) (e.g. methane-CH₄, nitrous oxide-N₂O and carbon dioxide-CO₂) emissions in animal feeding operations. The goal of this study was to quantify GHG emissions from the feedlot pen surface under North Dakota climatic conditions. In this study gaseous flux from the pen surfaces was generated using a custom-made wind tunnel at different times of the year (summer, fall, winter and spring). Gaseous fluxes (air samples) were drawn in the Tedlar bags using a vacuum chamber and gas concentrations were measured using a gas chromatograph within 24 h of sampling. The CH₄ concentrations and flux rates (FRs) or flux among the months were not significantly different. Overall CH₄, CO₂ and N₂O concentrations over a 7-month period were 2.66, 452 and 0.67 ppm, respectively. Estimated overall CH₄, CO and N₂O FRs were 1.32, 602 and 0.90 g m⁻² d⁻¹, respectively. Estimated emission rates using the wind tunnel were 38 g hd⁻¹ d⁻¹, 17 kg hd⁻¹ d⁻¹ and 26 g hd⁻¹ d⁻¹ for CH₄, CO₂ and N₂O, respectively. The emission factors for GHG estimated in the research for North Dakota climate were the first of its kind, and these emission estimates can be used as a basis for planning and implementing management practices to minimize GHG emissions.

Keywords:

• feedlot
• greenhouse gas
• wind tunnel
• flux rates
• emission rates

Acknowledgements

This project was supported by the State Board of Agricultural Research and Education (SBARE), North Dakota.