Methane emissions from paddy cultivation and livestock farming in Sarawak, Malaysia

In this study, implementation of Tier 1 methodology of 2006 IPCC (Intergovernmental Panel on Climate Change) Guidelines in paddy cultivation and livestock farming has been applied to estimate methane emissions in Sarawak, Malaysia within the years from 1998 to 2009. Methane emission inventory has been developed in this study, based on volume 4, 2006 IPCC Guidelines. Based on cultivation area and livestock population data as input to Tier 1 methodology, variations in paddy cultivation area and amount of livestock has been identified as the main contributor to emissions of methane. Methane emissions increased from 1.61 to 1.72 Gg CH4/year during 1998 to 1999. Based on results obtained, the outcomes show that there would be a significant drop of methane emission from buffalo and sheep. Although there are gain and loss in emissions from enteric fermentation, drastic reduction is observed from 0.65 Gg CH4/year in 1998 to 0.44 Gg CH4/year in 2009 as well as 0.05 Gg CH4/year to 0.02 Gg CH4/year for buffalo and sheep respectively. Simultaneously, methane emissions from manure management of buffalo has decreased from 0.024 Gg CH4/year in 1998 to 0.016 Gg CH4/year in 2009 while for sheep, its emission from manure management dropped from 0.002 Gg CH4/year in 1998 to 0.0007 Gg CH4/year in 2009. Overall emission from paddy cultivation can be considered in upward trend due to gain from 1998 at 1.61 Gg CH4/year to 1.67 Gg CH4/year in 2009. As an addition, significant rise in methane emission by 0.24 Gg CH4/year from 2000 to 2006 as well as 0.1 Gg CH4/year from 2007 to 2009 show momentum gaining in enteric fermentation of cattle. It also indicates future increment in methane emission from cattle which coherently affects the state’s emission level. As for emissions from manure management, emissions from cattle, goat and deer are gaining momentum in Sarawak