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Table 2. Comparison with other studies
No. Author Sector Parameters System boundary Main conclusion This study
1 Cai et al., 2018 [42] Waste disposal Reaction constants k and Direct emissions from landfills Methane emissions from landfills in China were Methane emissions from waste disposal in
i
methane production ratios included; upstream processes (e.g., 1.48 million tons in 2012. Compared with the China were estimated at 2.43 million tons in
derived from FOD model waste collection/transport) excluded BAU scenario in 2030, two mitigation scenarios 2018 and projected to decline to 0.11 million
parameters; waste were projected to reduce emissions by 0.60 and tons by 2030. By 2030, the BAU, UWR, and
[42]
composition based on 0.97 million tons, respectively ACRS scenarios are expected to reduce
regional averages methane emissions by 0.98~6.19 million
tons
2 Zhao et al., 2019 [46] Sewage treatment Emission factors from IPCC Direct methane emissions from Total methane emissions from municipal Assuming 10% methane collection, methane
Guidelines sewage treatment processes sewage treatment plants in 229 Chinese emissions from sewage treatment in China
(anaerobic/aerobic systems) prefecture-level cities reached 1.17 million tons were estimated at 1.67 million tons in 2018
in 2014, three times higher than the emissions
from similar plants in the United States in
[46]
2016
[47]
3 Zhao et al., 2024 Livestock and Emission factors from IPCC Methane emissions from rice From 2010 to 2019, total methane emissions Total methane emissions from livestock and
poultry manure (2006) Tier 1 & Tier 2 cultivation and five livestock from China’s agricultural sector decreased from poultry manure in China increased from
guidelines; manure categories (cattle, sheep, swine, 24.27 to 22.17 million tons. Methane emissions 2.04 million tons in 2018 to 2.26 million tons
management system poultry) via enteric fermentation and from livestock and poultry manure decreased by in 2022
proportions based on manure management 4.00 million tons between 2010 and 2016 [47]
provincial data
[26]
4 Xu et al., 2024 Livestock manure Emission factors from IPCC Methane emissions from enteric Methane emissions from China's livestock Assuming 10% methane collection, methane
(2006) Tier 1, China’s fermentation and manure industry decreased from 13.85 million tons in emissions from livestock manure in China
Provincial GHG Inventory management 2001 to 11.82 million tons in 2021. Methane were estimated at 2.24 million tons in 2021
Guidelines, and other emissions from manure management increased
literature from 1.76 to 1.92 million tons over the same
period, with an average annual emission of 1.95
[26]
million tons
[50]
5 Wang et al., 2021 Livestock Localized parameters from Methane emissions from rice Regions with high methane emissions from The provinces with the highest methane
management, China’s Provincial GHG cultivation, livestock enteric livestock management are primarily located in emissions from livestock and poultry
straw burning, Inventory Guidelines; straw- fermentation/manure management, western China, while regions with high farming are Henan, Hunan, and Sichuan.
waste disposal to-grain ratios and straw and waste treatment emissions from waste disposal are concentrated Methane emissions from waste disposal are
burning rates from NDRC in large cities such as municipalities and concentrated in populous provinces such as
data provincial capitals [50] Guangdong and Henan
[51]
6 Lu et al., 2024 Waste disposal, Locally measured data in All methane sources in Shandong Total methane emissions in Shandong Province From 2018 to 2022, total methane
sewage treatment, Shandong Province Province, including energy activities, in 2020 were 1.71 million tons [51] emissions from waste in Shandong Province
manure prioritized; supplemented agricultural activities, waste declined from 0.96 to 0.74 million tons
management with literature data treatment, and natural sources
amendment. By contrast, most other studies emphasize methane emissions from rice paddies and the utilization of straw as a soil amendment. Such
discrepancies in scope may introduce potential biases, which should be acknowledged in future research.