核心城市经济增长的极化与扩散效应直接影响城市群增长格局变动,长三角城市群核心城市增长极化效应的演化推动了该城市群由单核心向多中心发展。综合考虑经济规模权重的增长极化指数与经济增长溢出渠道的多元增长极化指数,及增长核心集中度指数等多指标的变化,本文对长三角城市群1995年以来增长格局特征及其演化的定量分析表明各指数基本呈现下降趋势,核心城市极化效应逐渐减弱,而核心城市增长的收敛性特征日益明显;长三角城市群均衡化发展的态势主要源于上海、苏州等地多核心的增长溢出效应带动了城市群内其他城市的快速发展;基于差异化的增长溢出渠道,不同城市发挥着增长核心作用。
The growth polarization and diffusion effect of the core cities directly affects the growth pattern of urban ag-glomeration. During the development of the urban agglomeration in Yangtze River Delta, the growth polarization effect features of the core cities keeps evolving, from a single core mode towards multi-core mode. By measuring the growth po-larization index considering the weight of economy scale and diversity growth polarization index considering the weight of different economic growth spillover channels, and concentration index of growth polarization, the paper quantitatively an-alyzes the characteristics and evolution of growth pattern of the urban agglomeration in Yangtze River Delta since 1995. The results show that the various indexes all decline, the polarization effect of core city weakens, the characteristics of growth convergence between cities become increasingly obvious, and the equalization development trend in the urban ag-glomeration in Yangtze River Delta has appeared, which mainly comes from the spillover effect of Shanghai, Suzhou and other growth poles in urban agglomeration driving the rapid development in the urban system economy;based on the dif-ferentiation growth spillover channels, different cities can play a role of growth core.