Embodied carbon flows in resource-based cities based on multiregional input–output model: a case study of Hohhot-Baotou-Ordos-Yulin urban agglomeration in China

Managing embodied carbon flows in the supply chains of resource-based cities is crucial to China’s carbon neutrality. However, the embodied carbon flows in these regions are still unclear. Taking the Hohhot-Baotou-Ordos-Yulin (HBOY) urban agglomeration as a case, this study reveals the process and critical pathways of embodied carbon flows in resource-based cities by using environmentally extended multiregional input–output model and structural path analysis. The results indicated that embodied carbon flows from high-to-low emission intensity along the supply chain in HBOY. Spatially, Ordos located upstream in the supply chain, exhibited a net carbon outflow of 11.24 Mt to midstream and downstream areas, while Hohhot situated downstream, demonstrated a net carbon inflow of 6.87 Mt from upstream and midstream areas. Sectorally, a significant flow of embodied carbon from the electricity and heat supply industry to the construction industry and other service industry was observed, with 11.55 Mt and 10.08 Mt, respectively. The embodied carbon flows in HBOY were mainly driven by fixed capital formation, with 44.40% of the emissions in the top 20 critical paths attributed to it. To ensure the achievement of extensive carbon emission reduction targets in resource-based cities, it is essential to complement emission reduction measures on the production side with differentiated regional and sectoral policies that leverage the characteristics of embodied carbon flows.