Estimation and geographical mapping of enteric methane emission from large ruminants under different production systems in Pakistan.

Methane (CH₄) emission estimation from large ruminants reared in different production systems in Pakistan shows that milk producing animals majorly receive forage-based diet that is high in cellulose fiber along with concentrates to meet the nutritional requirement. The variability in diet is linked with different production systems in which animals are reared. The objective of this study was to estimate enteric methane emission (EME) of large ruminants reared in different production systems in Pakistan using IPCC Tier 2 guidelines and statistical models separately for cattle and buffalo. For 90.8 million population of large ruminants, cumulative CH₄ emission was 126.49 CO₂-Eq. (13.86 Gg per day and 5058.9 Gg in 365 days). Cattle shared a percentage of 48.4% with 40.66 CO₂-eq from Punjab and 20.73 CO₂-eq form Sindh province while buffalo shared a percentage of 51.6% with 45.41 CO₂-eq from Punjab and19.69 CO₂-eq from Sindh province. The percent difference in CH₄ production is assumed to be due to a greater number of animals being shifted from rural production system to commercial production system (population) and type of feeding strategies being implemented on these production systems (nutrition). To give mitigation strategies for EME in Pakistan, an accurate large dataset of EME estimates from whole country specifically from smallholder subsistence is required.