中国城市企业数量空间分布及规模分布演变

The evolution of spatial and size distribution in the quantity of Chinese urban enterprises

针对城市规模研究忽视企业数量且企业分布研究集中在空间分布的问题,将企业数量纳入城市规模指标,提出从空间分布及规模分布研究企业分布及演变的方法.结果表明:1)中国企业空间分布极不均衡,胡焕庸线东南半壁企业数约占95%且比例仍在增大;企业数增长率整体符合东南高、西北低的规律,但黑龙江、新疆等地城市与规律相悖.2)城市首位度远低于理想值,首位城市优势不明显;企业数整体服从Zipf分布,集中于中间位序城市且在趋近理想分布;使用分层研究划分为3个无标度区,无标度区之间断层明显,第一无标度区内城市约占90%,企业集中于中间位序城市,第二、三无标度区城市企业集中于高位序城市.该方法有助于立体描述企业分布的现状及趋势,为合理布局生产力、科学确定城市规模提供参考.

Previous researches have analyzed urban scales in terms of population,area and gross domestic product,but few studies have addressed the scale of enterprise agglomeration in these areas.In this paper,the gap was filled by investigating the spatial distribution and size distribution of enterprises for more rational development plans in rapidly growing municipalities.（1）The results of spatial distribution indicate that Chinese enterprises are distributed unevenly and that most enterprises are located in southeast and inland cities.The southeast part of China,as delineated by the Hu Line,contains about 95 percent of enterprises while taking up only 43 percent of territory.Annual growth rates of enterprise quantity in southeast cities are greater than those in northwest ones,however,cities in Heilongjiang and Xinjiang don＇t comply with the law.（2）The results of size distribution demonstrate that three urban primacy indexes are far less than the ideal values.The frequency distributions of urban enterprises follow Zipf＇s law on the whole,but three Zipf dimensions are consistently less than the ideal value.Nevertheless,these values come closer to the ideal value.Thus it is able to be inferred that enterprises are concentrated in middle-rank cities and are approaching the ideal distribution state.Based on the fractal theory,cities are divided into three scale-free intervals.The first scale-free interval contains around 90 percent of cities,with enterprises concentrated in middle-rank cities.In contrast,enterprises are centralized in high-rank cities in the second and third scale-free intervals.From the perspective of spatial distribution and size distribution of enterprises,our research contributes to better understanding on the present situation and tendency of enterprise distribution in China to support the optimization of productivity layouts and determination of reasonable urban scales.