广东区域公路网络的城市通达性度量及空间特征分析

以广东省各地级市辖区和县域中心点为公路网络节点,通过对各节点城市的中心职能强度指数分析及其相互之间在公路网络的连通关系为基础,综合应用日通达性模型、通达性度量模型和潜力模型,对广东区域通达性进行分析,并以不同指标和度量模型的广东区域通达性的空间格局和分异特征进行GIS分析。结果表明,广东省的城市通达性空间格局,总体上呈现出一种圈层空间分布结构,以广州市核心区域和佛山市中心区域(禅城区和顺德区)为中心向外辐射。其影响通达性区域差异的主要因素包括城市经济水平、交通条件和地理区位等,其中,在交通条件影响下的通达性区域差异,在空间上表现出高等级公路网络指向性。研究结果反映出广东省省域公路网络通达性的空间分异规律,诠释了城市的经济发展水平、交通条件和地理区位对通达性的综合作用,从而为广东省城镇网络体系发育、区域经济协调及珠三角产业转移规划优化提供科学支撑。

Regional Accessibility Measurement and Spatial Characteristics Analysis Based on Road Networks in Guangdong Province

The adjustment of industrial structure and layout optimization in Guangdong Province is significant, as China is at a critical stage with an impressive acceleration of economic globalization and regional integration process. In order to support the regional economic coordination and the industrial transfer planning, as well as lay out optimization in Guangdong Province, this paper studied and qualified the regional accessibility based on the road networks, and characterized the spatial patterns of regional accessibility with different measurement models. Firstly, cities in Guangdong Province are represented by the nodes in road networks. Secondly, the urban function indices of all cities are introduced to represent their size and economic level, respectively. Then, accessi-bility measurement models, including daily accessibility model, accessibility measurement model based on ma-trix analysis, and potential model, are applied to evaluate and qualify the regional accessibility and their spatial patterns. Finally, GIS is used to characterize the spatial patterns and differences of the accessibility derived from difference models. The results show that the spatial patterns of the regional accessibility in Guangdong Province are represented by concentric sphere structures with the center located at the core of Guangzhou and within the Chancheng and Shunde districts in the city of Foshan. The spatial representations of the regional accessibility dif-ferences show clear directivity derived from highway networks, and reflect the composite effects of urban geo-graphic locations, transportation conditions and economic levels. Particularly, the cities in the Pearl River Delta at the center of Guangdong Province have the best accessibility and economic ties intensity. But the cities in the north, east and west wings of Guangdong, who are distant from the economic center, i.e. the Pearl River Delta, have the worst accessibility. This reveals the weak associations in the spatial and economic interactions between these cities