Optimizing Green-Space Allocation in Plateau Cities: An Adaptive Reconfiguration Framework for the Late Urbanization Stage: A Case Study of Kunming

At present, most plateau-constrained cities worldwide—plateau cities whose spatial form is strictly constrained by topography—have entered the late stage of urbanization. The relationship between urban form and the surrounding geographic spatial pattern has consequently exhibited distinctive new characteristics. However, planning and policy often continue to adopt green-space allocation schemes developed in the mid-stage of urbanization and based on the experience of plain cities, resulting in difficulties in plan implementation, intensified human–land conflicts, and imbalances in both the supply–demand relationship and equity of green public services with severe challenges to urban sustainable development, calling for urgent correction and reconstruction. Through a literature review and comparative case analysis, this study clarifies global trends in the paradigm shift in plateau-city planning and develops an evaluation system comprising “adaptability analysis of originally planned spaces within the built-up area + assessment of the potential for converting ecological value in green spaces outside the built-up area + integrated spatial optimization.” Building on Analytic Hierarchy Process (AHP) weighting and spatial analysis, the study establishes a comprehensive assessment framework and applies it empirically to Kunming as a typical case, with the aim of proposing a correction-and-reconstruction paradigm for green-space allocation tailored to plateau-constrained cities to achieve sustainable development goals. The results indicate a widespread paradigm shift in many cities from “pattern optimization during incremental expansion” and “passive adaptation to ecological patterns” toward “enhancing governance effectiveness during stock-based renewal” and “proactive innovation in governance instruments.” The Kunming case shows that, during the mid-stage of urbanization, numerous parks and green spaces were planned within the built-up area (flat land), yet many of these proposals proved infeasible due to excessive costs and trade-offs. Meanwhile, the adjacent mountainous ecological spaces with substantial scenic and recreational potential were long excluded from the urban public service system. In response, this study proposes a three-dimensional allocation model that combines “optimized adaptation” within the built-up area and “potential conversion” in adjacent peri-urban areas together with differentiated policy instruments and an implementation/transfer assurance mechanism. This approach not only offers practical planning guidance for Kunming but also provides a broadly applicable set of theoretical and practical tools for improving land-use efficiency and promoting green equity in similar cities worldwide.