Climate-Related Emissions from Feedyards Monitored
Thedairysite.com, October 30th
US - An accurate estimation of nitrous oxide and methane emissions from beef cattle feedlots is an increasing concern given the current and potential future reporting requirements for greenhouse gas emissions
Dr Ken Casey, Texas A&M AgriLife Research air quality engineer in Amarillo, is working on an ongoing study to quantify the nitrous oxide and methane emission rates from pen surfaces at two commercial beef cattle feedlots in Texas.
This research was supported in part by Agriculture and Food Research Initiative Competitive Grant from the US Department of Agriculture National Institute of Food and Agriculture, AgriLife Research and Texas Cattle Feeders Association.
To put these in perspective, nitrous oxide and methane have global warming potentials of 310 times and 21 times that of carbon dioxide, respectively, Dr Casey said. This means these gases trap more heat within the atmosphere than carbon dioxide per unit weight.
His AgriLife Research study was set up to determine the range of nitrous oxide and methane emission rates from feedlot pen surfaces; to obtain an understanding of seasonal, temporal and spatial variability of emission rates within pens; and to gain insight into the factors that influence and control emission rates, such as moisture content, days since rainfall and nitrogen content. In his study, the emissions from the pen surfaces were measured on 20 sampling days from June to October 2011, Casey said. The air samples were collected from the chambers’ headspace at 0, 10, 20 and 30 minutes using syringes, transferred to evacuated vials and analyzed with a gas chromatograph.