研究以非参数模型计量为基础,从集聚-分散维度和单中心-多中心维度刻画了上海都市区就业、人口空间演化特征,并与北京都市区的研究结果进行了横向比较。研究表明,上海都市区的就业和人口不断向外扩散,同时近、远郊均出现了稳定的再集中,就业和人口的空间多中心性都在增强。而北京只存在人口的分散化和多中心化,就业却呈现集中化和单中心化的态势。因而,上海都市区的就业-人口空间匹配程度高于北京。产业结构差异是造成北京、上海两地就业空间演化特征分异的原因之一,上海制造业比重高于北京,郊区的制造业集聚强化了近、远郊吸纳就业能力,促进了多中心空间结构的形成。北京和上海中心城区的就业、人口规模仍在扩张,导致近邻地区被包络在内,原有的次中心逐渐消失,因而,科学确定中心城区的增长边界,有效防止邻近蔓延,应当成为特大城市未来发展的关注重点。
The paper aims to generalize the characteristics and evolution of spatial structure in Shanghai Metropolitan Area, and also to compare the basic results with those of Beijing Metropolitan Area. To demonstrate the spatial evolution of both employment and population distribution in Shanghai, we have applied nonparametric methods to the analysis, which contains two perspectives of 'agglomeration-dispersion' and 'monocentricity-polycentricity'. Our study has concluded that there is a continuous and evident dispersion in both population and employment distribution since the 1990s, and our study has identified the significant concentrated sub-centers in peripheral areas, which strengthened the polycentricity of the metropolitan area. As for Beijing, the overall trend of population evolution tends to be dispersed and polycentric, but the spatial distribution of employment is generally concentrated in central areas, which is contrary to the decentralization of population. According to our comparative analysis, the employment and population spatial distributions match better in Shanghai. We have also discussed about the reasons for different phenomena in Shanghai and Beijing. Differences of industrial structure between Beijing and Shanghai may be one of the most important causes for the employment distribution disparity, owing to the fact that Shanghai's manufacturing share is higher than Beijing's and the industrial dispersion helps promote the ability of absorbing employment in suburban areas and form the polycentric urban spatial structure. As for Beijing, service industry plays a significant role in recent years. Service industry often requires face-to-face communication, as a result, enterprises tend to form an agglomeration and reinforce the centralization, leading to a much more monocentric urban spatial structure. Meanwhile, in both Beijing and Shanghai, the population and employment sizes in central districts still matter a lot, which has already made some employment sub-centers not significant. There