Comparison of models for estimating methane emission factor for enteric fermentation of growing-finishing Hanwoo steers

Abstract

The methodology provided by the Intergovernmental Panel on Climate Change (IPCC) guidelines is widely used for estimating enteric methane (CH 4 ) production by cattle. No attempt other than the default values in the IPCC Tier 1 has been made for estimating CH 4 emission from Hanwoo, a dominant beef species in Korea raised in a unique feeding system. The objective of this study was to compare models for estimating the CH 4 emission factor (MEF; kg CH 4 /head/year) for enteric fermentation in Hanwoo steers. The MEF was estimated based on Korea-and Hanwoo-specific data obtained from the literature using several models. The models include the IPCC Tier 1 (T1), the IPCC Tier 2 method (T2), the IPCC Tier 2 methodology with actual dry matter intake (T2DMI), and the Japanese Tier 3 method (JT3). The JT3 was included due to the similarity in the beef cattle production system between the two countries. Estimated MEF using T2 were 43.4, 33.9, and 36.2 kg CH 4 /head/year for the growing, finishing, and overall period, respectively. The overall MEF estimated using T2 was 23 % lower than the estimate by T1 (47.0 kg CH 4 /head/year). There were significant differences in the estimated MEF for enteric fermentation of Hanwoo steers among the methods (P < 0.05). The overall MEF estimated by JT3 was 69.1 kg CH 4 /head/year, which was significantly higher than the estimates by T2 (36.2 kg) and T2DMI (33.5 kg). The JT3 estimated the highest values in all periods possibly due to overestimation of the conversion ratio of feed energy to CH 4 . No significant difference was found in the overall MEF of Hanwoo steers between T2 and T2DMI. However, T2DMI estimated 8 % higher and 14 % lower MEF than T2 for the growing and finishing period, respectively, mainly because the T2 significantly over-predicts the gross energy intake of Hanwoo steers at the high level of intake. The IPCC default methods have limitations in their use for a feeding systems in non-western countries, and thus development of a country-specific methodology and parameter estimates for enteric CH 4 production is required for Hanwoo and other cattle production systems.

Effects of different feeding systems on ruminal fermentation, digestibility, methane emissions, and microbiota of Hanwoo steers

“…In this study, the MEF was 57.59 in the SF group and 61.18 in the TMR, comparable to the Korean inherent emission factor. Jo et al [ 56 ] analyzed several MEF prediction methods; Hanwoo steers MEF at the finishing stage was predicted as 33.9 when the IPCC Tier 2 method was used. However, Bharanidharan et al [ 7 ] reported that Hanwoo steers MEF measured through respiration chambers was 35.1 in SF and 49.4 in TMR, higher than those predicted by Jo et al [ 56 ] and lower than the measured values in this study.…”

Estimation of Greenhouse Gas Emission from Hanwoo (Korean Native Cattle) Manure Management Systems

“…In this study, annual emissions of CH 4 and N 2 O emission from the Hanwoo cattle manure management systems were almost 5.4 and 2.1 times, respectively higher than the values provided by IPCC. Jo et al reported that such variation might be attributed to the differences in feeding systems and cattle breeds as the values mentioned by IPCC values were estimated based on the studies conducted mainly in western countries [21]. Country-specific emission factors are, therefore, needed rather than using the values of the 2006 IPCC GL to develop effective and efficient GHG emission reduction strategies for the livestock industries.…”

“…According to the Hanwoo traceability system, the number of cattle amounted to 3.07 million in 2019, representing more than 86% of the total cattle population in Korea [20]. Hanwoo cattle has been identified as the major contributor of the GHG emissions from the cattle production sector in Korea as well as showed higher enteric GHG emissions than other breeds [21,22]. However, none of the studies have estimated GHG emissions from Hanwoo cattle manure management systems, which acts as the main hindrance to developing national GHG emissions statistics for livestock sector in Korea.…”

Mitigasi Gas Rumah Kaca Subsektor Peternakan di Kabupaten Subang, Jawa Barat

“…Jika dilihat dari persen penurunannya, maka hasil estimasi dengan Tier 2 lebih rendah sekitar 21,82% sampai 27,86% dibandingkan dengan jika diestimasi menggunakan Tier 1. Seperti yang dilaporkan oleh Jo et al (2016), bahwa penghitungan dengan menggunakan Tier 2 di Korea dengan menggunakan faktor emisi local, memberikan nilai emisi yang lebih rendah 8 -14% dibandingkan dengan jika digunakan penghitungan dengan metode Tier 1.…”