Unequal transfer and its policy implications of carbon emissions and economic benefits embodied among Central Plains urban agglomeration

Tracing the carbon emissions and economic benefits embodied in trade is crucial for the equitable allocation of mitigation responsibilities, particularly among cities in China, where studies on this topic are lacking. Therefore, this study selected the Central Plains Urban Agglomeration (CPUA) as a representative region. It compiled carbon emissions inventories following the 2006 IPCC guidelines and employed the multi-regional input-output model to investigate the trade-attributed embodied carbon emissions and value-added. Additionally, it estimated the unequal transfers of these emissions and value-added by introducing the City Carbon Emissions Inequality index (CCEI). The results indicate that the CPUA received net carbon emissions of 454.99 and 330.95 Mt. from outside regions from 2012 to 2017. Nearly half of the territorial carbon emissions were driven by the consumption of other cities, and Zhengzhou and its surrounding cities transferred the most carbon emissions to the outer-ring cities by consuming the primary products produced in these cities. The construction sector was the largest exporter of both embodied emissions and economic benefits, while the energy and service industries were the largest importers of carbon emissions and economic benefits. Such imbalanced transfers contributed to carbon inequality, with the CCEI mean increasing from 0.31 to 0.38 for the exacerbation of intercity imbalances in development. Significant carbon inequality occurred between Zhengzhou and its upstream cities, e.g., Luoyang and Shangqiu, and among some neighboring cities, e.g., Yuncheng-Jincheng and Luoyang-Jiyuan. Our findings provide evidence of a need for compensation mechanisms and collaborative strategies for carbon mitigation in the urban agglomeration.