An estimation of enteric methane emissions from cattle in Bangladesh

Abstract

In Bangladesh, cattle are increasing day by day as not only unemployed people but also employed people are doing farming now-a-days. It is a matter of great concern for Bangladesh that effects of greenhouse gases also increasing gradually because some of greenhouse gases e.g., methane, carbon dioxide, nitrous oxide are also component of expiratory gases of cattle respiration. This studyestimatedthe enteric methane emission from cattle in Bangladesh. Inter-governmental Panel on Climate Change (IPCC) guidelines were followed in the whole study. As IPCC guidelines, Tier-1 and Tier-2 methods for the calculation of total methane emission from cattle were used. In calculation, the study has recorded the emission of methane from cattle using Tier-1 method based on emission factors provided by both IPCC-2006 (T1) and IPCC-2019 (T1a). It also showed the emission value by using Tier-2 system based on dry matter intake. Finally, the study compared our different calculated values for different IPCC provided emission factors and for different methods. After calculation, in 2016, 2017, 2018, 2019 and 2020-2021 total emission of methane from cattle using T1 method based on the emission factors provide by IPCC-2006 were 932.43, 938.08, 942.48, 947.15 and 1177.18gigagram respectively and based on emission factors provided by IPCC-2019 (T1a) total emission were 1348.93, 1357.10, 1364.08, 1371.52 and 1577.04gigagram respectively. Using Tier-2 method, total emission of methane in those years were 970.95, 976.51, 981.20, 986.19 and 1203.74gigagram respectively. IPCC 2019 (T1a) based cattle methane emissions appear to overestimate than the T1 and Tier 2 calculations, suggesting that Tier 2 method which is variable enriched than T1 should be adapted to estimate national cattle methane emissions.