Department of Animal Production and Technology, Chinhoyi University of Technology, Off-Chirundu Road Private Bag, 7724, Chinhoyi, Zimbabwe.
Grasslands Research Institute, Agricultural Research Innovation and Development Directorate, Fifth Street Extension P O, Box CY594, Causeway Harare, Zimbabwe.
Trop Anim Health Prod. 2023 Mar 15;55(2):111. doi: 10.1007/s11250-023-03539-x.
The effectiveness of methane mitigation in ruminant livestock production systems depends on the accuracy of estimating methane emission factors and providing accurate emission inventories. Following the Paris Climate agreement, it is recommended that countries adopt the Tier-2 approach for estimating enteric methane emissions from ruminants instead of the Tier-1 approach currently used by most countries. This study sought to provide base line enteric methane emission estimates for the Tuli and Mashona Sanga cattle breeds in Zimbabwe using the IPCC Tier-2 model. Using animal characterization data collected from 412 cattle from Grasslands Research Institute and 406 cattle from Makoholi Research Institute, net energy requirements were estimated. From this and the estimate for digestibility, gross energy intake and dry matter intake were estimated. Gross energy intakes and the estimated methane conversion factor were used to estimate enteric methane emissions. Mean emission factors for Tuli were 45.1, 56, 28.5, 28.4 and 20.6 kg CH/head/year for cows, bulls, heifers, steers and calves, respectively. For Mashona, they were 47.8, 51.9, 29, 29.1 and 20.7 kgCH/head/year for cows, bulls, heifers, steers and calves, respectively. Generally, estimated Tier-2 emission factors were significantly different from the IPCC Tier-1 default emission factors. This study concluded that enteric methane emission factors estimated using the IPCC Tier-2 model offer insights into the controversial use of the default IPCC Tier-1 emission factors.
反刍家畜生产系统中甲烷减排的有效性取决于甲烷排放因子估算的准确性和提供准确的排放清单。根据《巴黎气候协定》，建议各国采用 Tier-2 方法估算反刍动物的肠道甲烷排放，而不是大多数国家目前使用的 Tier-1 方法。本研究旨在使用 IPCC Tier-2 模型为津巴布韦的图利和马绍纳桑加牛品种提供肠道甲烷排放的基准估计。利用从 Grasslands Research Institute 收集的 412 头牛和 Makoholi Research Institute 收集的 406 头牛的动物特征数据，估算了净能量需求。由此，估计了消化率、总能摄入量和干物质摄入量。利用总能摄入量和估算的甲烷转化率来估算肠道甲烷排放量。图利牛的平均排放因子分别为 45.1、56、28.5、28.4 和 20.6 kg CH/头/年，用于奶牛、公牛、小母牛、阉牛和小牛。对于马绍纳，它们分别为 47.8、51.9、29、29.1 和 20.7 kgCH/头/年，用于奶牛、公牛、小母牛、阉牛和小牛。一般来说，估算的 Tier-2 排放因子与 IPCC Tier-1 默认排放因子有显著差异。本研究得出结论，使用 IPCC Tier-2 模型估算的肠道甲烷排放因子为有争议地使用默认的 IPCC Tier-1 排放因子提供了深入了解。
