Synergy of carbon - pollution - ecology ——The future of synergetic reduction of pollution and carbon emissions

Against the backdrop of intensifying global climate change and environmental pollution, the synergetic reduction of pollution and carbon emissions (SRPCE) has become a pivotal focus in environmental governance and policy-making. The integration of ecosystem services into this framework offers a promising approach to simultaneously enhance ecosystem quality, improve human well-being, and achieve dual objectives of environmental quality improvement and climate change mitigation. Nevertheless, current research and practical applications have largely neglected the collaborative dimension of ecosystem services in SRPCE strategies. This study, focusing on the Yellow River Basin and Haihe River Basin, investigates the spatial synergies among regional pollutants, carbon emissions, and ecosystem services through the development of a novel Carbon-Pollution-Ecology Synergy Index (CPESI). Our findings demonstrate substantial spatial heterogeneity in achieving the intertwined goals of pollution reduction, carbon mitigation, and ecosystem service maintenance, primarily driven by land use changes. Based on the analysis of CPESI results, only 4.1 % of areas achieve triple synergistic enhancement in ecosystem services, pollution carbon emission control. The area proportions of Double synergistic increased, Double synergistic descended, and Triple synergistic descended are 89.6 %, 5.9 %, and 0.4 %. Meanwhile,19.82 % of regions demonstrate a “dual synergy” pattern where pollution reduction coexists with carbon emission, highlighting systemic neglect of ecological service valuation in current governance. Through systematic quantification of the synergistic benefits between emission reduction (both pollutants and carbon) and ecosystem service enhancement, this research develops a comprehensive assessment methodology that effectively integrates environmental and ecological objectives, which serves as a valuable decision-support tool for optimization of cross-regional ecological and environmental governance policies.