京津冀城市群空间扩张及其经济溢出效应

随着我国城市化的快速发展,区域城市之间的联系逐渐加强,不同的扩张模式对城市间经济增长溢出效应会产生不同的影响。基于Capello模型,计算了京津冀城市群地区13个城市扩张带来的经济增长溢出效应,通过比较扇状扩张城市和轴向扩张城市得到和给出的城市增长溢出效应,研究了不同扩张类型城市溢出效应的差异,以及京津冀地区经济增长溢出效应的空间分布特征。结果表明,京津冀城市群地区城市间经济增长溢出效应明显,北京和天津给出的溢出效应远高于其他城市,扇状扩张城市比轴向扩张城市更有利于城市之间的增长效益溢出。京津冀地区已经形成了以北京、天津、廊坊和唐山为中心的核心区,石家庄、保定为核心的次级核心区,位于城市群边缘的城市与核心城市联系较弱,在未来的城市群发展中,可通过政策和规划优化城市形态,使城市空间形态更有利于城市经济发展。

Urban expansion and its spillover effects on economic growth in the Beijing-Tianjin-Hebei urban agglomeration

There are different types of expansion during urban development, and the relationship between regional and urban economies has gradually strengthened with rapid urbanization in China. Different spatial patterns of urban expansion have different effects on growth spillovers of the urban economy; however, there is limited information on the relationships between urban expansion and growth spillovers. In this study, we evaluated the growth spillover effects of the urban economy at an urban scale using the Capello model in the Beijing-Tianjin-Hebei urban agglomeration from 1984 to 2015. There are three types of spatial pattern of urban expansion: ring-, belt-, and fan-shaped, to analyze urban growth spillovers. The results revealed that the spillover effects of economic growth are obvious among 13 cities in the Beijing-Tianjin-Hebei urban agglomeration and displayed the differences of urban growth spillovers between belt- and fan-shaped cities in this area. From 1984 to 2015, there were remarkable economic growth spillover effects in the Beijing-Tianjin-Hebei urban agglomeration; however, the effects of growth spillovers were much greater in Beijing and Tianjin than in other cities, and were unbalanced in other areas; the effects of growth spillovers were higher for fan- than for belt-shaped cities. Based on the results, Beijing, Tianjin, Tangshan, and Langfang were the core areas in the Beijing-Tianjin-Hebei urban agglomeration, followed by Shijiazhuang and Baoding as sub-core areas, and cities on the edge of urban agglomerations showed weak relationships with the core cities. In the future, in the Beijing-Tianjin-Hebei urban agglomeration, the urban spatial form could be optimized through urban policies and planning, so it would be more conductive to urban economic development.