Strategies for synergistic reduction of plastic leakage and greenhouse gas emissions in China.

Urban synergistic carbon emissions reduction research: A perspective on spatial complexity and link prediction

Municipal solid waste (MSW) management systems play a crucial role in greenhouse gas (GHG) emissions in China. Although the government has implemented many policies to improve the MSW management system, the impact of these improvements on city-level GHG emission reduction remains largely unexplored. This study conducted a comprehensive analysis of both direct and downstream GHG emissions from the MSW sector, encompassing sanitary landfill, dump, incineration, and biological treatment, across 352 Chinese cities from 2001 to 2021 by adopting inventory methods recommended by the Intergovernmental Panel on Climate Change (IPCC). The results reveal that (1) GHG emissions from the MSW sector in China peaked at 70.6 Tg of CO2 equiv in 2018, followed by a significant decline to 47.6 Tg of CO2 equiv in 2021, (2) cities with the highest GHG emission reduction benefits in the MSW sector were historical emission hotspots over the past 2 decades, and (3) with the potential achievement of zero-landfilling policy by 2030, an additional reduction of 203.7 Tg of CO2 equiv is projected, with the emission reduction focus toward cities in South China (21.9%), Northeast China (17.8%), and Southwest China (17.3%). This study highlights that, even without explicit emission reduction targets for the MSW sector, the improvements of this sector have significantly reduced GHG emissions in China.

In light of the interrelated origins and processes of greenhouse gas (GHG) and atmospheric pollutant emissions, countries around the world are actively seeking synergistic strategies for their reduction. Urban transportation represents a critical sector for GHG and air pollutant emissions; however, the effectiveness of existing collaborative measures has proven inadequate. This ineffectiveness primarily stems from a focus on terminal emission reductions, neglecting potential pollutant emissions that arise during implementation. To address this gap, this paper develops seven scenarios for coordinated emission reductions in urban transportation and employs econometric methods to quantitatively assess the effectiveness of these strategies throughout their entire lifecycle. Furthermore, the evaluation integrates key indicators, such as synergistic emission reduction, a coordinated control system, and cross-elasticity, to provide a comprehensive analysis of the proposed measures. This paper uses Shenyang, China, as a case study, revealing that enhancing fuel quality emerges as the most critical strategy for synergistic emission reduction. Although the comprehensive synergistic emission reductions associated with rail transit and low-carbon travel are not the highest, they demonstrate a significant linkage effect. Although the promotion of new energy vehicles (NEVs) offers substantial terminal emission reductions, their energy generation processes and consumption during charging classify them as non-synergistic measures. This study addresses the prevalent issue of overemphasizing terminal governance, providing valuable insights for policymakers in the urban transportation sector. It facilitates a deeper understanding of the synergistic control characteristics of various measures, enabling the identification of effective strategies and the exploration of their interconnections.

Addressing climate change and improving air quality are prominent tasks facing China’s ecological environment. The synergistic emission reduction in greenhouse gases (GHGs) and air pollutants has become an important task of environmental governance in different provinces. In this study, Hebei Province was taken as the research object. Firstly, the emission factors of GHGs (CO2, CH4, and NO2) and air pollutants (SO2, NOX, and smoke & dust) in Hebei Province from 2011 to 2020 were calculated and analyzed. Seven socio-economic indicators were selected to analyze the trend during the study period. The Spearman rank correlation coefficient method was used to analyze the correlation between GHG and air pollutant emissions. Finally, the synergistic control effect coordinate system and the cross-elasticity coefficient of emission reduction were used to study the synergistic emission reduction effect of GHGs and air pollutants. The results showed that the total amount of GHG emissions fluctuated slightly from 2011 to 2020, and energy activities were the main source of total GHG emissions. The total emissions of air pollutants decreased year by year, and decreased by 71.13% in 2020 compared with 2011. During the study period, the emission synergy between smoke & dust and GHG was better than that between SO2, NOX, and GHG. GHG and SO2, NOX, and smoke & dust achieved synergistic emission reduction in most years, but the overall emission reduction synergy was poor.

As of 2023, China’s transportation energy carbon emissions account for over 10%, which has a significant impact on achieving “dual carbon” goals. China has successively issued various policies to address pollution emissions in the transportation industry. This study mainly analyzes the synergistic effects of pollution reduction and carbon reduction measures implemented in this industry. We selected 2023 as the base year, focused on promoting new energy vehicles (NEVs), advocating bus transit (ABT), and advancing rail transit (ART) as the three major emission reduction policies, and analyzed their synergistic effects on air pollutant control and greenhouse gas emission reduction. Based on national scale data on driving conditions, energy consumption, and emission factors, the synergistic emission reductions in greenhouse gases and air pollutants brought about by the three policies were first calculated. Then, using the coordinate system of synergistic control effects, cross elasticity analysis of pollutants, and normalization evaluation methods, the multi pollutant synergistic control capabilities of each policy were quantified. Quantitative results revealed that the NEV substitution policy achieved a CO2 reduction of 100.966 million tons in 2023, alongside reductions of 1.0196 million tons (CO), 59,506 tons (NOx), 103,500 tons (NMHC), 6266 tons (PM10), and 3071 tons (SO2). Based on the APeq ranking, its comprehensive benefits (APeq = 166,734.52) significantly outperform ART (APeq = 97,414.89) and ABT (APeq = 19,796.80). The main research conclusion shows that replacing private gasoline cars with new energy vehicles can have a synergistic emission reduction effect on all five types of air pollutants and greenhouse gases involved in this study, with a positive synergistic effect. Moreover, the policy development priority is relatively better based on the synergistic emission reduction equivalent. Both buses and rail transit have not brought about SO2 emission reduction, nor have they had a positive synergistic effect on SO2 and CO2 emission reduction. On this basis, buses also contribute to NOx emissions. For other air pollutants, both rail transit and buses can have a synergistic effect of reducing pollution and carbon emissions.

Evaluation of PM2.5 and CO2 synergistic emission reduction and its driving factors in China

Developing collaborative and effective strategies for reducing reactive nitrogen (Nr) and greenhouse gas (GHG) emissions is key to maintaining human activities within planetary boundaries. Nitrogen (N) management not only promotes Nr emission and pollution control but also influences GHG emission sources. Therefore, we constructed a nitrogen-carbon (N-C) coupled model to link N metabolism with GHG emission inventory at the national scale, revealing the contributions of N management for synergistic GHG emission reduction. China was selected as the case study. The results showed that from 2015 to 2020, the N-metabolism system was associated with 1510 Mt carbon dioxide (CO2)eq yr-1 of GHG emissions, including CO2, methane, nitrous oxide, and C sequestration, accounting for 13.5% of the national level. Adopting N-C coupled strategies could synergistically reduce N-associated GHG emissions by 42.1% (607.8 Mt CO2 eq), suggesting that the Nr-GHG comitigation effects have been considerably underestimated. Specifically, the most effective synergistic strategies were balanced N fertilizer use, manure management, food loss, and waste reduction, and garbage sorting, which may become a priority for future N-C synergistic emission reduction.

Evaluation of CO2 and SO2 synergistic emission reduction: The case of China

This report summarizes the findings and recommendations of a three-year study on greenhouse gas (GHG) emissions in China and options for abatement over the coming decades. Macroeconomic modeling results show that the continuation of rapid economic growth in China could result in a threefold increase in GHG emissions between 1990 and the year 2020. Specific measures for limiting GHG emissions are examined in detail, including improvements in energy efficiency, more rapid introduction of non-fossil energy technologies, afforestation for carbon sequestration, and modifications to various GHG-producing agricultural practices. In the short- to medium-term (before 2010), energy efficiency holds the greatest potential for low-cost GHG emission reduction. Over the longer term, however, the only option for China and the world is to switch to non-carbon energy sources. The study concludes that a two-pronged strategy for reducing GHG emissions in China should be adopted, whereby (i) economic reform and policy initiatives are continued for the purpose of improving resource allocation and encouraging energy conservation, and (ii) a set of priority investment and technical assistance programs are undertaken which promote the acceleration of more efficient and low-carbon technologies and which improve the institutional and human resource capacities to implement and sustain these programs.

Domestic regional synergistic emission reduction is important in achieving national climate goals. This study constructed a game theory-based model for regional synergistic emission reduction, modified the Basic Climate Game using the exact-hat algebra method, and expanded the game model using a general spatial equilibrium model to incorporate cross-regional economic impacts generated by emission reduction actions through factors and product flows. The formation of regional comparative advantages in emission reductions and their impact on synergistic emission reductions were revealed through regional characteristics such as emission elasticity, sectoral structure, regional trade shares, and green total factor productivity. A form of synergy was then proposed that utilizes the comparative advantages of different regions, allowing for synergistic emission reductions across different income regions and engagement with regions that are still at the carbon-peaking stage in cooperation. Moreover, the model was created to be as close to the economic reality as possible to provide a trade, industry, and economic growth policy that complements emission-reduction policies.

Trajectory, driving forces, and mitigation potential of energy-related greenhouse gas (GHG) emissions in China's primary aluminum industry

Under the “dual carbon” goals, heavily polluting enterprises face dual pressures to reduce both pollution and carbon emissions, necessitating the urgent exploration of effective pathways for coordinated emission reductions. This study investigates the potential of digital transformation in enterprises to achieve synergistic emission reductions. First, the entropy method is employed to measure enterprise digitalization and pollutant levels, and the spatial–temporal evolution characteristics of regional coordinated emission reductions are analyzed. Subsequently, using panel data from heavily polluting enterprises in the Yangtze River Economic Belt, the study examines the impact of digital transformation on pollution and carbon reduction, its underlying mechanisms, and the moderating effects of environmental policies on these relationships. Robustness tests confirm the synergy between carbon and pollution emissions. The findings reveal that digital transformation contributes to the synergistic reduction of carbon and pollutant emissions in enterprises, primarily through two pathways: the coordinated integration of internal innovation resources and the collaborative engagement in external innovation networks. Furthermore, air pollution control policies and low-carbon city initiatives significantly enhance the synergistic emission reduction effects of digitalization. Interestingly, heavily polluting enterprises located in the downstream regions of the Yangtze River, those with smaller operational scales, or those facing strong financing constraints, demonstrate more pronounced synergistic emission reduction effects through digital transformation. Based on these conclusions, we recommend that governments focus on strengthening either “pollution reduction” or “carbon reduction” policies, as either alone can yield dual emission reduction benefits. Additionally, tailoring regional emission reduction policies to local conditions can maximize economic and environmental benefits.

Can carbon emission trading policy enhance the synergistic emission reduction of carbon dioxide and air pollutants? A comparative study considering different pollutants

Achieving synergistic governance of air pollution treatment and greenhouse gas emission reduction is the way for the Chinese government to achieve green transformational development. Against this background, this paper takes the implementation of the carbon emissions trading system (ETS) as the breakthrough point, using the time-varying difference-in-differences (DID) model to explore the synergistic emission reduction effect of ETS on air pollution and carbon emissions and its mechanism. The results indicate that the implementation of ETS not only significantly reduces CO2 emissions but also synergistically achieves the reduction of air pollutants, and the synergistic emission reduction effect is mainly achieved through the synergistic reduction of SO2. Moreover, the emission reduction effect of ETS has economic and regional heterogeneity. On the one hand, the ETS has a more prominent carbon reduction effect in less developed provinces and cities and has a significant synergistic emission reduction effect on SO2 and PM2.5; on the other hand, the carbon emission reduction effect of ETS is more potent in Beijing, Hubei, and Shanghai, followed by Tianjin and Chongqing, and the weakest in Guangdong. In addition, through the analysis of the mediating effect, this paper finds that reducing energy consumption, optimizing the energy structure, and improving energy efficiency are effective ways for ETS to achieve synergistic emission reduction. This study provides valuable policy enlightenment for promoting the synergistic governance of pollution and carbon reduction.

Low-carbon development path research on China’s power industry based on synergistic emission reduction between CO2 and air pollutants