京津冀都市圈大都市阴影区的GIS界定

Delinitation of Metropolitan Shadow Area in Beijing-Tianjin-Hebei Metropolitan Region

大都市阴影区是由于中心城市及其周边区域因集聚、辐射作用的不同组合关系而形成的一种发展落差现象。本文介绍了大都市阴影区的形成和演化机制,并以京津冀都市圈为例,利用Huff模型、K-means聚类和空间自相关等方法划分了都市圈的影响圈层与范围,界定了2012年都市圈的"大都市阴影区",总结出了通过GIS的空间分析手段界定"阴影区"和"半阴影区"的方法。研究发现:利用GIS空间分析手段可以定量、直观地界定大都市阴影区和半阴影区;京津冀都市圈的大都市阴影区主要存在于以北京为中心的西北和西南两翼,京津冀自然本底条件和区位差异决定了人口和经济活动布局的空间不均衡性,国家实施区域不均衡发展战略导致人口和产业快速向京津等沿海地区集聚,政策、交通、经济要素和产业结构是造成京津冀都市圈阴影区形成的主要因素。提出大都市阴影区的消减对策应依据大都市区中心城市、外围区域和阴影区三者关系来制定。

The shadow areas of metropolis is a phenomenon of development gap formed by the different combination of agglomeration and radiation among the central city and its surrounding areas. This article reviewed a number of metropolitan shadow theories regarding formation and evolution mechanisms. By using Huff model, K-means cluster and spatial auto-correlation, this article defines the ranges of metropolitan shadow areas in 2012 in Beijing-Tianjin-Hebei （BTH） metropolitan region, and summarizes the method of defining shadow area and semi shadow area by means of GIS spatial analysis. Results are indicated as follows： by means of GIS spatial analysis, the metropolitan shadow area and penumbra area can be defined quantitatively and intuitively. The metropolitan shadow areas of BTH metropolitan exist in the northwestern and southwestern of Beijing City. The natural background conditions and location differences determine the spatial disequilibrium of population and economic activities, and the unbalanced regional development strategy has led to the rapid agglomeration of population and industry into coastal areas such as Beijing and Tianjin. Regional or local policy bias, transportation condition, economic factors and industrial structure account for the formation of shadow area in BTH metropolitan regions.To reduce the effects of metropolitan shadow, the centre city should optimize its regulation and the shadow areas should adopt positive strategies.