地球科学と気候変動ジャーナル

抽象的な

Assessment of Methane and Nitrous Oxide Emissions from Livestock in India

Arvind K. Jha, Khem Singh, C. Sharma, S. K. Singh and Prabhat K. Gupta

Methane emission contribution from Indian livestock is the highest (>70%) as compared to various other subsectors from agriculture sector viz. rice cultivation and open burning of crop residue. Methane emission factor (MEF) for ruminant livestock has been developed and is based on the country specific activity data. Methane emission from Indian livestock is estimated as 9.92 ± 2.37 Tg for the year 1994. Major emissions are from enteric fermentation (~90%) and are estimated to be around 8.97 ± 2.22 Tg, while from manure management is only around 0.95 ± 0.15 Tg. Nitrous oxide emissions from livestock is small and is estimated to be around 0.99 Gg in 1994. Methane emission was highest from cattle followed by buffalo and other species in livestock. Among the Indian states, Uttar Pradesh (UP) is the highest methane producer followed by Madhya Pradesh (MP), Bihar and Rajasthan due to their larger and denser livestock population. However the highest methane emission density per square kilometer is estimated for Punjab followed by West Bengal and Bihar. Methane emission from livestock had increased in last decades viz. from 9.0 Tg in 1981 to 9.9 Tg in 1992 mainly due to increase in animal population. It had stabilized thereafter mainly due to stabilization in animal population. India is deficient in livestock’s feed resources. Low milk productivity and high methane generation per kg milk in Indian livestock is due to animal’s feed having low quality roughage based diets with nutrient deficiency.