青藏高原高寒牧区冷季补饲藏系绵羊温室气体排放特征

Greenhouse Gas Emissions from Tibetan Sheep with Supplementary Feeding in Alpine Pasture in Qinghai-Tibet Plateau During Cold Seasons

为了揭示藏系绵羊温室气体排放特征,在青藏高原高寒牧区采用密封式呼吸箱-气相色谱结合的方法,于2013年冷季对3只身体健康、均重(50.13±1.28)kg的藏系绵羊温室气体(CH4、CO2、N2O)日排放特征进行了研究。试验期间,动物日粮的精料为蒸煮饲料,粗粮为青干草饼。结果表明,藏系绵羊的CH4排放日动态具有明显规律性,排放峰值在8:00和17:00(P<0.01),排放峰值的出现时间与饲喂时间基本吻合,最小值出现在次日7:00;CO2的日排放曲线相对平稳;N2O的日变化没有明显规律且排放量极低。在冷季补饲模式下,藏系绵羊的CH4、CO2和N2O日排放量分别为(16.17±1.27)、(549.18±20.63)g·head-1和(0.73±0.32)mg·head-1。

Greenhouse gas emissions from raising ruminants contribute to the global greenhouse gas production. This study presented results on greenhouse gas（including CH4, CO2, and N2O）emissions from Tibetan sheep with supplementary feeding in Qinghai-Tibet Plateau. A combination of respiration chamber and GC methods was used to examine the diurnal patterns of greenhouses gas emissions in 3 Tibetan sheep [Average body weight （BW）=（50.13±1.28）kg] during cold season in 2013. The animals were fed with steamed concentrate diets and dry grass biscuits. The chamber was applied right prior to the measurements. Methane emission curve was characterized with apparent diurnal pattern, with emission peaks occurred at 8：00 am and 17：00 pm and the lowest emission rate appeared at 7：00 am. The rates of CO2 emissions remained relatively stable through a day. However, N2O emissions were quite low. The daily emissions of CH4, CO2 and N2O from Tibetan sheep were（16.17±1.27）,（549.18±20.63）g·head-1 and（0.73±0.32）mg·head-1, respectively.