高质量发展背景下中国城市群多中心空间结构与地区差距研究

The stage of China's economy has changed from speed growth to quality development currently. This makes promoting coordinated development become a major problem to be solved urgently in the main battlefield of China's economy. At the same time, promoting the polycentrilization of spatial structure within urban agglomerations in order to improve its balanced development is becoming one of the important spatial intervention policies in China. Conceived by planners and policymakers, polycentricity is regarded as a useful policy tool to level out differences between regions and generate more balanced territorial development. However, whether this polycentric spatial structure can effectively promote balanced development within the region still lacks effective empirical support. This proposed study aims to fill this empirical deficit by providing reliable evidence on the question of whether a polycentric urban structure of urban agglomerations can reduce regional disparities. It takes urban agglomeration as the research unit, constructs the measurement system of spatial structure covering three dimensions (Morphology-Function-Politician), and focus on solving the reverse causality problem which has long been criticized in empirical analysis. In addition, this research also intends to explore the mechanism from four aspects: agglomeration (dis)economies, agglomeration shadow/borrowing size, network externalities and administrative intervention, and refine the feasibility suggestions for optimizing and guiding the spatial structure of urban agglomerations. As far as the theoretical and practical meaning is concerned, this project can not only deepen the theory of spatial structure and regional sustainable development, but also promote the application of basic research results, and guide the formation of urban agglomerations' rational spatial structure in China.

目前我国经济已由高速增长阶段转向高质量发展阶段，推进区域的协调发展成为我国经济主战场亟待解决的重大问题。以城市群为主体空间形态，通过推动城市群空间结构的多中心化来促进城市群内部均衡发展，正成为我国重要的空间干预政策之一。然而，多中心空间发展战略是否能真正有效地促进区域内均衡发展还缺少有效的实证支撑。本项目拟以城市群为研究主体，构建涵盖形态—功能—行政三个维度的空间结构测度体系，并着重解决实证分析中备受诟病的反向因果问题，将多中心空间结构与城市群内部差距间的分析建立在严谨的因果推断上。此外，还拟从集聚经济/不经济、集聚阴影/规模互借、网络外部性和行政干预四个方面探索多中心影响城市群内部差距的机理和作用路径，提炼城市群空间结构优化和引导的可操作性建议。项目不仅能丰富和深化空间结构和区域可持续发展的相关理论，还有助于促使基础研究成果走向应用，指导我国城市群形成合理的空间结构。

推进区域的协调发展是我国经济主战场亟待解决的重大问题，而通过推动空间结构的多中心化来促进区域均衡发展，则是我国重要的空间干预政策。项目主要进行了三大块研究：识别城市并测度多中心空间结构，分析多中心空间结构的绩效表现以及探索空间结构影响因素及作用机制。研究发现包括：1）城市个数随着时间的推移稳定增加，实体城市主要分布在城镇化水平相对较高的胡焕庸线以东地区，实体城市的空间范围随着年份的增加也不断扩大；多中心在时间上空间结构的演变十分稳定，不同年份之间的空间结构的改变十分有限。2）互联网能显著促进城市内部的就业集聚，但随互联网渗透率的提高，其促进作用呈现边际递减趋势；创业者在区位选择上的确存在家乡偏好，且这种偏好在生存型和机会型的创业者中均普遍存在。创业者偏好在家乡创业是为了借助熟悉的社会网络拓展营销渠道并照顾子女和父母。3）相对于多中心而言，具有单中心人口分布的地级市更有可能缩小区域差距；多中心空间结构的经济影响效应趋于较小，且没有明显的方向倾向；中国地级市市域的多中心空间结构程度越低，整体绩效（经济效率、空间公平性和环境可持续性）越好。本项目回应高质量发展的背景下推进区域协调发展的重大需求，为未来区域发展战略和城市规划发展提供科学的理论依据，还有助于确定空间结构优化的方向推动区域形成合理的空间格局。