WANG Cong, CAO Youhui, CHEN Guowei
In the process of globalization, urban network has become research frontier of domestic and foreign scholars. By using research tools of western academics, this article analyses urban network development characteristics of the Yangtze River Delta region based on producer services from three aspects, which are hierarchy structure, network mode and functional characteristics. Studies have shown that urban network of the Yangtze River Delta region based on producer services has a significant hierarchy structure, but not entirely in conformity with the existing urban hierarchy characteristics, in which cities like Kunshan and Yiwu play the role of important network center. Meanwhile, the network connection between cities also shows significant sequence relationship by importance, and the network of producer services between three core node cities(Shanghai, Nanjing and Hangzhou) forms the most important network links of the Yangtze River Delta region. From the influence sphere of the three core nodes, Shanghai network has the most remarkable directivity and is most widely covered, while that of Nanjing and Hangzhou is no longer merely confined to within their own province area. The development trend of flat structure is increasingly significant. The core area with a "Z"-shaped one by traditional Shanghai, Nanjing, Hangzhou and Ningbo has turned to spread to the northern region of Nantong, Yangzhou and southern part of Shaoxing and other regions. According to the different network characteristics formed by different types of producer services, 11 departments could be classified into three types:perfect type, flat type, and professional type. The network formed by banking and finance,insurance and IT functions reveals prominent hierarchy phenomenon, and develops a relatively complete network, so it is called the perfect type. Cities covered by real estate,securities, logistics functions has more functions, but its hierarchy phenomenon is not obvious, and the distribution of the functional center is more scattered, thus it is known as the flat type. The distribution of network function center formed by accounting, law, advertising,management consulting, design and service functions is more concentrated, at the same time,in addition to the function center, the service value of other node cities is very small,therefore it is called a professional network.