Location: Livestock Nutrient Management ResearchTitle: Diurnal variation in greenhouse fluxes from a feedyard pen surface
Submitted to: ASA-CSSA-SSSA Annual Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 4/1/2017
Publication Date: N/A
Technical Abstract: Accurate estimation of greenhouse gas (GHG) emissions, including nitrous oxide (N2O) and methane (CH4) from open-lot beef cattle feedlots is an increasing concern given the current and potential future reporting requirements for GHG emissions. Research concerning N2O and CH4 emission fluxes from the manure management system at feedlots, however, has been very limited. This study was conducted to quantify the diel variation in N2O and CH4 flux rates from pen surfaces at a commercial beef cattle feedlot in Texas during 2017. Fluxes from pen surfaces were measured hourly using Licor Long-Term Chambers on 5 sampling days during summer, in a 5-d measurement campaign. Six chambers were arranged in two rows of three, strategically covering representative areas of the pen, including areas near feedbunks and water troughs. A custom built multiplexer sequenced air from each chamber to a Los Gatos Research Enhanced Performance Model N2O/CO analyzer and a Los Gatos Research Enhanced Performance Model CH4/CO2/H2O/NH3 analyzer. From the N2O and CH4 concentrations, flux densities were calculated using linear regression. Further ongoing work is investigating flux rates in other seasons and identifying contributing factors.