都市区空间结构与经济发展的互动关系研究

The Interaction Between Urban Spatial Structure and Economic Development

文章采用结构方程模型实证检验空间结构与经济发展的互动关系。研究发现,中国都市区已经进入多中心分散阶段,空间结构与经济发展存在因果关系,即经济发展水平的提高会扩大人口规模,规模增加则导致集聚不经济上升,并促进空间结构多中心化。多中心化后的空间结构由于降低了集聚不经济而进一步提高生产率。因而,传统地理学中关于两者互动发展的描述得到实证支持;同时明确了多中心化的直接动力是人口规模的增加,而不是经济发展水平的提高。这些发现对于优化当前中国的城市与区域空间战略具有重要的启示。

Urban spatial structure is believed to be born out of socio-economic development, so it is subject to the stage of economic development, and also influences the economic activities. The interactive relationship between spatial structure and economic development has always been the core issue of economic geography. Exploring this relationship helps to optimize the urban spatial structure and benefit economic performance. Previous related studies are abundant with theoretical descriptions, but lack of empirical supports, and some mechanisms are not elaborated clearly enough. This article examines the interaction between spatial structure and economic development with econometric models. Traditional linear regression models with single equation can only test one-way relationship, this study uses structural equation models to estimate the relationship between several dependent variables such as urban labor productivity, population and polycentricity from an overall perspective. The results show that： 1） Most Chinese cities have entered the stage of morphologically polycentric spatial structure; 2）There exists an interactive causal relationship between spatial structure and economic development; 3） The polycentricity is driven by urban population size, rather than economic growth. The concrete circular causality between spatial structure and economic development is as follows, the population expands with the economic development, then promotes the formation of polycentric spatial structure probably driven by the rise of agglomeration diseconomy; the increasing polycentricity improves the urban labor productivity likely due to the weakened agglomeration diseconomy. In addition, the polycentric spatial structure is also closely related to high second industry ratio and proportion of small firms; and urban population is depended on the historical population and industrial structure, higher ratio of second industry and more population in 1953 lead to bigger size of urban population. These findings have important policy implications for optimizing urban spatial strategies in China. Overall, polycentricity should be encouraged by urban spatial policies in China. Moreover, considering that the population size rather than economic growth boosts the polycentricity, for megacities like Beijing and Shanghai or cities in developed coastal areas, the polycentric strategy can be used to reduce agglomeration diseconomy and improve economic performance; for small and medium-sized cities or cities in less developed middle and west China, policy should also be conducted to decrease the external diseconomies of agglomeration, the mono-centric spatial structure can still benefit the economic performance there.