CONTINUOUS AMMONIA EMISSION MEASUREMENTS FROM A COMMERCIAL BEEF FEEDYARD IN TEXAS Academic Article uri icon

abstract

  • Ammonia emissions from cattle feedlots pose the potential to react with other compounds such as oxides of nitrogen and sulfur, which lead to detrimental environmental effects. Ambient ammonia (NH 3) concentrations were measured continuously at a beef cattle feedyard for 12 months beginning in March 2007. Concentrations were measured every 5 min, 24 hours per day, at a sample intake height of 3.3 m using a chemiluminescence analyzer. On-site weather data were collected concurrently. Modeled emissions of NH 3 were compared with the mass balance of N for the feedyard. Mean annual NH 3 concentrations were 0.57 ppm, with a monthly average low of 0.37 ppm in December 2007 and a monthly average high of 0.77 ppm in August 2007. Flux densities were calculated using a backward Lagrangian stochastic model (WindTrax 2.0.7.8). Mean annual flux density was 70.7 g m -2 s -1 (2.2 kg m -2 year -1). Mean monthly flux density ranged from 42.7 to 123.1 g m -2 s -1 (0.11 to 0.32 kg m -2 month -1) in November and April 2007, respectively. Both concentration and flux density had a diel distribution with minima during the nighttime hours and maxima during the early afternoon. On an annual basis, 48.8% of fed N was volatilized as NH 3. The inverse modeled daily ammonia production per head was 85.3 g NH 3-N (head fed) -1 d -1. 2008 American Society of Agricultural and Biological Engineers.

published proceedings

  • TRANSACTIONS OF THE ASABE

author list (cited authors)

  • Rhoades, M. B., Parker, D. B., Cole, N. A., Todd, R. W., Caraway, E. A., Auvermann, B. W., Topliff, D. R., & Schuster, G. L.

complete list of authors

  • Rhoades, MB||Parker, DB||Cole, NA||Todd, RW||Caraway, EA||Auvermann, BW||Topliff, DR||Schuster, GL

publication date

  • December 2010