Sustainable urbanization requires reconciling rapid land development with ecological security, a challenge particularly acute in mountainous megacities. While land-use/cover change (LUCC) substantially reshapes regional carbon storage, conventional whole-region assessments often mask critical spatiotemporal dynamics and subregional heterogeneity. Taking Chongqing, China, as a representative case, this study integrates the Future Land-Use Simulation (FLUS) and Integrated Valuation of Ecosystem Services and Trade-offs (InVEST) models to decode historical carbon-storage dynamics (2000–2020) and simulate future spatial trajectories (2035) under four multi-scenario land-use pathways: Integrated Development Priority Scenario (IDPS), Ecological Conservation Priority Scenario (ECPS), Farmland Conservation Priority Scenario (FCPS), and Economic Priority Scenario (EPS). Results show a net decline of 8.49 × 106 t in total carbon storage during 2000–2020, primarily driven by the often-overlooked degradation of high-carbon-density grasslands alongside construction-land expansion. Scenario simulations reveal that the ECPS is the only pathway achieving a net carbon-storage increase (+4.26 × 106 t), although the resulting land-use pattern was jointly shaped by ecological protection constraints, land suitability, and scenario-specific land-demand allocation. Crucially, subregional analysis highlights distinct spatial roles: the Northeastern Urban Agglomeration (NUA) emerges as the core for ecological restoration, the Main Urban Area (MUA) remains highly sensitive to development-driven carbon loss, and the Southeastern Urban Agglomeration (SUA) acts as a buffer requiring a delicate development balance. By linking coupled spatial modeling with subregional constraints, this framework advocates for a shift from “one-size-fits-all” land management to precise spatial governance, providing a scalable scientific reference for carbon-oriented sustainable planning in mountainous megacities worldwide.
Jin et al. (Mon,) studied this question.