不同采气方法对六氟化硫示踪法测定肉牛甲烷排放量的影响

Effect of Different Gas Extraction Methods on Determination of Methane Emission Results by Six Sulfur Fluoride Tracer Method

为研究不同采气方法对六氟化硫示踪法测定牛甲烷(CH4)排放的影响,试验选取18头6月龄夏洛来杂交牛作为研究对象,随机分成A、B、C三组,每组6头(实际采样时每组随机选用牛头数为5头),饲喂相同日粮,采用六氟化硫(SF6)示踪技术测定牛CH4排放量。A组为对照组,使用牛扼法采气;B组和C组采用定时定点法采气,B组每2h采集1次,采集24h;C组每1h采集1次,采集12h(每天10∶00~22∶00),连续采样5d。试验期30d。结果表明:三组测得的CH4排放量差异不显著(P>0.05)。采样期内三种采气方法所测得CH4排放量变化趋势基本一致。因此,可根据试验需要采用定时定点采气法测定牛CH4排放量。

To Study the effect of different gas extraction methods on the determination of CH4 emission by sulfur hexafluoride tracer method,eighteen 6-month-old Charolais crossbred cattle were selected as the research object,and randomly divided into A,B,C three groups,6 pigs in each group,fed with the same diet.Sulfur hexafluoride(SF6)tracer method was adopted to determinate the CH4 emission amount of bovine.Group A was used as control group,and traditional sampling was adopted to collect gas.Group B and group C were collected by fixed point method,group B was collected 1 time per 2 h,lasting for 24 h;group C was collected for 1 time per 1 Hfor 12 h(10∶00~22∶00 every day),continuously for 5 d.Test period was 30 d.The results showed that there was no significant difference in the CH4 emissions between the three groups(P>0.05).The change trend of the CH4 emission measured by three gas extraction methods during the sampling period was basically the same.Therefore,the gas extraction method by fixed time and place can be used to determine the CH4 emission of cattle according to the test.