Low-carbon competitiveness of cities in solid waste disposal systems: Spatial and temporal variations in greenhouse gas emissions in the Yangtze River Delta

As one of the major sources of greenhouse gas (GHG) emissions, the municipal solid waste (MSW) management system was regarded as a key contributor to the construction of a low-carbon society. Understanding the evolution of waste treatment facilities and the corresponding GHG emissions was essential for assessing the low-carbon competitiveness of local communities. In this study, facility-level data were used to estimate GHG emissions from the waste management system in the Yangtze River Delta (YRD) and analyze their temporal and spatial variations. The mitigation potential for GHG emissions in 2025 and 2030 was evaluated based on source separation and technical measures. The results showed that net emissions from the system had decreased after peaking at 16.34 Mt CO₂-eq in 2021 due to the large number of incineration plants commissioned with lower emission intensity. Emission intensities not only reflected the shift in treatment technology but also served as an indicator of local government management capabilities. Provincial capitals usually exhibited lower emission intensities, with an average of 0.19 t CO₂-eq/t MSW due to advanced and large-scale disposal systems. Mitigation efforts should focus more on the accumulated MSW in landfills currently, and approximately 62.98 % of the mitigated GHGs from landfills could be achieved through low-cost measures such as cover layer oxidation, resulting in a reduction of 2.57 Mt CO₂-eq. This study provided a methodological framework for estimating GHG emissions and mitigation potential in waste management system, offering valuable insights for other regions and countries with necessary local adjustments.