Dynamic Methane Emissions from China's Fossil-Fuel and Food Systems: Socioeconomic Drivers and Policy Optimization Strategies.

In response to the 2023 "Action Plan for Methane Emission Control" in China, which mandates precise methane (CH) emission accounting, we developed a dynamic model to estimate CH emissions from fossil-fuel and food systems in China for the period 1990-2020. We also analyzed their socioeconomic drivers through the Logarithmic Mean Divisia Index (LMDI) model. Our analysis revealed an accelerated emission increase (850.4 Gg/year) during 2005-2015, compared to 570.4 Gg/year in the preceding period (1990-2005), with a downward trend (-1216.6 Gg/year) detected after 2015. The fossil-fuel system was the primary contributor to these changes, with emissions positively correlated with per capita GDP and negatively influenced by energy intensity at the production stage and wastewater discharge intensity at the disposal stage. In the food system, CH emission intensity and waste treatment practices were the most significant negative drivers at production and disposal stages, respectively. Urbanization also played a notable role, contributing to 19.3% and 18.1% in livestock and rice cultivation emission reductions, respectively. Despite the observed changes, coal mining, livestock, and rice remain the dominant sources of CH emissions. Our findings suggest that effective CH emission mitigation can be achieved through strategies such as reducing energy intensity, improving agricultural production efficiency, and advancing urbanization efforts.