Mapping Regional Flows: Supply Chain Pathways of Black Carbon Emissions in China

As the world’s largest anthropogenic emitter of black carbon (BC), China exhibits substantial regional disparities in emissions. This study integrates provincial data into an endogenized multi-regional input–output (MRIO) framework and applies structural path analysis (SPA) to trace embodied BC emissions across 30 Chinese regions throughout the full economic cycle. The results indicate that Southern China is the region with the highest emissions (191.85 Kt), while the northwest region, despite having the lowest absolute emissions, exhibits the highest emission intensity (9.59 kg per 105 CNY). Only 8.94% and 15.66% of the BC emissions linked to Shanghai and Beijing were produced locally, compared to 79.23% for Shandong and 79.21% for Hebei. Most BC emissions in the supply chain originate from direct emissions by the residential sector, followed by indirect emissions from carbon-intensive industries such as construction. This pattern reflects a mechanism whereby final demand in developed provinces stimulates economic output in less developed provinces, thereby driving BC emissions there. These findings highlight the need for differentiated regional mitigation strategies—such as residential clean energy transitions in underdeveloped regions and sustainable supply chain management in developed ones—to advance national sustainability goals.