Abstract
Reducing pollution and carbon is essential to achieve China's goal of "carbon peaking and carbon neutrality"; however, the collaborative paths of pollution and carbon reduction remain vague and worth exploring. This paper analyses panel data from 30 provinces in China from 2002 to 2017 to determine the impact of environmental decentralization on the synergy of pollution and carbon reduction in pig farming. The result shows that environmental decentralization has a significant 'carbon reduction effect' and 'pollution reduction effect' on pig farming; it is also conducive to promoting the synergistic effect of reducing pollution and carbon emissions through supporting environmental facilities and industrial organisations. Various types of environmental decentralization have significant differences in the synergy of pollution and carbon reduction. The scale of pig breeding plays a positive regulatory role in the impact of environmental decentralization on the synergy of pollution and carbon reduction while showing regional heterogeneity. This research is crucial for advancing the green transformation of pig breeding.