基于力学视角的中心城市扩张惯性模拟与调控

Along with the inevitable global urban expansion and the aggravating ecological damage, the expansion of central cities in our country highlights the dilemma of three imbalance lines, which is the breakthrough of elastic expansion rational boundary, the approach of urban environment ecological bottom line and the overstep of development up line. How to scientifically simulate the inertia situation of central cities’ urban sprawl and regulate the obivious problems, has become the major proposition and realistic problem of urban sustainable development and social management in our country and cities..In view of these problems, firstly, by improving the traditional hypothesis of “restraining expansion”, this project envisages the urban expansion of central cities on the basis of a new research paradigm of “researved space”. Secondly, based on mechanics theory, an analysis framework of “current boundary identification - inertial boundary deduction - science boundary measurement” to “reserved space definition” is constructed. Thirdly, using the technical methods of space identity in geography, data mining, mechanical analysis of classical mechanics and the equilibrium analysis of economics, four aspects of the research mainly carries out: the identification of central cities’ current expansion boundary and the diagnosis of temporal-spatio evolution characteristics, the reveal of land expansion mechanism and the simulation of inertial space, the equilibrium measure of land expansion inertial space and delimitation of boundaries, and the multi- scenario set of land expansion and the design of regualtion system and policy, to provide a scientific basis for regulating urban expansion dilemma and sustainable development management in our country.

伴随全球城市扩张难以避免、生态损毁困境不断加剧，我国中心城市扩张呈现更加凸显的失衡三线困境（扩张弹性突破“合理界线”、城市环境逼近“生态底线”和发展态势逾越“指标上线”），因此，如何科学模拟中心城市扩张惯性态势、调控凸显困境，成为我国城市可持续发展和社会管理的重大命题和现实难题。.鉴于此，本项目改进“遏制扩张”传统假说，从“预留空间”新的研究范式出发首先正视中心城市扩张，进而基于力学视角构建从“现状边界识别-惯性边界推演-科学边界测度”到“预留空间确定”的分析框架，并融合地理学的空间识别与数据挖掘、经典力学的受力分析、经济学的均衡分析等技术方法，重点开展中心城市扩张现状边界识别及时空演化特征诊断、土地扩张力学机理揭示及惯性空间模拟、土地扩张惯性空间均衡测度及边界划定和土地扩张多情景设置及调控制度与政策设计4方面研究，以便为我国城市扩张困境调控和可持续发展管理提供科学依据。

伴随我国中心城市扩张呈现更加凸显的失衡困境，本项目重点开展中心城市扩张现状边界识别及时空演化特征诊断、土地扩张力学机理揭示及惯性空间模拟，并基于土地价值均衡原理，定量划定城市扩张惯性空间边界，进而设计适合我国国情的调控制度与政策，主要研究发现和结果如下：.第一，时空诊断发现，长江经济带城市规模存在明显的位序-规模分布格局，建成区规模呈现“东高西低”、“轴线高两端低”的特征，建成区密度呈现“一个中心，两个次中心”的特征；城市由点源聚集增长向轴线式扩张转变，国土空间“T”型增长格局逐渐显现。.第二，耦合效应表明，在耦合效应较强阶段，上海和苏州的相互引力较强，杭州对苏州和上海的辐射引力较强；伴随核心城市发展由起步走向成熟，城市GDP总额和产业结构特征不断变化，其相互作用引力先增强后减弱最终趋于稳定，并与建设用地扩张的耦合效应逐渐加强。.第三，边界划定发现，融合MCR与CA模型划定的徐州市2020年、2025年和2030年城市开发边界规模分别为529.69km2、589.36km2和698.98km2；基于适度边界融合“三线”冲突后，徐州市2025年城镇开发边界线内建设用地、永久基本农田保护红线和生态保护红线规模分别为378.54km2、55.21km2和76.63km2。.总之，通过本项目研究在《Sustainable Cities and Society》（SCI）、《农业工程学报》（EI）、《中国人口·资源与环境》（CSSCI）等国内外高水平期刊发表论文30篇，出版专著1部，研究成果达到预期目标，相关研究结论和政策建议得到同行专家和决策者较高关注，并获得省部级以上主要领导审阅批示，对城市扩张困境调控和可持续发展管理具有较高参考价值和指导意义。