title: Methane emissions from a dairy feedlot during the fall and winter seasons in Northern China.
abstract: Accurately determining methane emission factors of dairy herd in China is imperative because of China's large population of dairy cattle. An inverse dispersion technique in conjunction with open-path lasers was used to quantify methane emissions from a dairy feedlot during the fall and winter seasons in 2009-2010. The methane emissions had a significant diurnal pattern during both periods with three emission peaks corresponding to the feeding schedule. A 10% greater emission rate in the fall season was obtained most likely by the higher methane emission from manure during that period. An annual methane emission rate of 109±6.7 kg CH4 yr(-1) characterized with a methane emission intensity of 32.3±1.59 L CH4 L(-1) of milk and a methane conversion factor (Ym) of 7.3±0.38% for mature cattle was obtained, indicating the high methane emission intensity and low milk productivity in Northern China.
authors.affiliation: College of Resources and Environmental Sciences, Agricultural University of Hebei, Baoding 071000, China. zhilinggao@hebau.edu.cn
authors.forename: Zhiling
authors.initials: Z
authors.lastname: Gao
authors.forename: Huijun
authors.initials: H
authors.lastname: Yuan
authors.forename: Wenqi
authors.initials: W
authors.lastname: Ma
authors.forename: Xuejun
authors.initials: X
authors.lastname: Liu
authors.forename: R L
authors.initials: RL
authors.lastname: Desjardins
mesh_terms: D000818:Animals; D002417:Cattle / Q000378:metabolism*; D002681:China; D002940:Circadian Rhythm; D003612:Dairying; D008697:Methane / Q000378:metabolism*; D012621:Seasons
chemical_list: D008697:Methane