长江经济带三大城市群经济差异演变及影响因素——基于多源灯光数据的比较研究

Spatial-Temporal Evolution and Influencing Factors of Economic Disparities Among Three Urban Agglomerations in the Yangtze River Economic Belt:A Comparative Study Based on Multisource Nighttime Light Data

基于DMSP-OLS和NPP-VIIRS夜间灯光数据构建夜间灯光总量集成序列,采用Dagum基尼系数、标准差椭圆、重心转移模型及地理探测器等定量方法,系统比较1995-2015年长江经济带三大城市群经济差异时空演变及影响因素。结果表明:①三大城市群经济规模呈东中西梯度递减特征,经济增速呈西中东梯度递减特征。总体差异、群内差异及群间差异均逐年缩小,群间差异为总体差异的主要来源。②三大城市群经济空间结构均存在“路径依赖”现象,在期初的基础上不断强化。经济空间分布均呈西北-东南走向,但呈现出不同的离散趋势。③政府投资、市场水平及对外开放是推动三大城市群之间及各城市群内部经济差异的核心因素,人口规模、医疗水平、文教水平及交通水平等因子的作用随城市群区域及阶段的变化而有所差异。

Based on the DMSP-OLS and NPP-VIIRS nighttime light data, this study develops a time series of total nighttime light (TNL) from 1995 to 2015 and multidimensionally analyzes the spatial-temporal evolution and influencing factors of economic disparities among three urban agglomerations in the Yangtze River Economic Belt applying the method of Dagum Gini coefficient, standard deviational ellipse, gravity-center model and geographical detector model. Results indicate that: 1) TNL of three urban agglomerations appears a gradient descent from east to west, while the growth rate of TNL presents a gradient decline from west to east. Overall disparity among the three urban agglomerations is downgrade year by year, as well as discrepancies between and within urban agglomerations. Differentia between urban agglomerations is mainspring of the overall disparity. 2) Path dependence phenomenon exists in the spatial structure evolution of each urban agglomeration, which is constantly strengthened on the basis of the early stage. 3) Government investment, market situation and openness are the core factors influencing economic differentiation of the three urban agglomerations. The effects of population scale, medical level, educational level and traffic level differ with the changes of regions and development stages of urban agglomerations. Results can provide a scientific basis for the optimization of economic spatial distribution in each urban agglomeration and promoting the coordinated development of the three urban agglomerations.