End of rope or phoenix nirvana? Exploring the evolutionary paths of coal resource-based cities in China

Coal resource-based cities (CRBCs) face a complex transformation of the urban system due to the adjustment of the global energy structure and the need for sustainable development worldwide. Considering the urban system as the combination of urban carriers and urban loads, this study proposed a framework to illustrate the evolution of CRBCs using resources and environmental carrying capacity (RECC). Taking 30 CRBCs in China as research objects, the EWM-TOPSIS method and the Geographically and Temporally Weighted Regression (GTWR) model were introduced to assess the comprehensive performance and identify the influencing factors from 2011 to 2020. With most CRBCs becoming more sustainable in the past decade, the results showed two evolutionary paths: urban carrier expansion and urban load reduction. Furthermore, urban conditions and evolutions were spatially agglomerated, and the natural resources sustainability in urban carriers and the environmental pollution in urban loads were the main factors affecting the two paths mentioned above, while the declining population was the major challenge for the shrinking CRBCs. These findings offered valuable insights to guide the sustainable transformation of CRBCs in different situations.