Abstract:

The urban fringe does exist impersonally, but it is difficult to identify it precisely. Current methods have some difficulty in combining spatial precision with linkage of spatial units and attribute data. There are two problems in current methods such as the single-factor-method and the multiple-factor-method for identifying the rural-urban fringe spatially. One is the spatial precision, and the other is the poor linkage of spatial units and attributes data. As viewed from industrial activities, this article believes that rural-urban fringe is a result of dual effects of urbanization and sub-urbanization. Based on industrial structure character and industrial distribution, this article has proposed a new single-factor-method for indentifying the urban fringe spatially by dint of some analysis instruments such as non-linear regression, spatial auto correlation and GIS. In addition, this article has made a case study of Beijing City by using the data of 1996 and 2001 National Basic Unit Surveys. The method proposed in this article can be further divided into four steps. First, the method estimates spatial distribution functions of manufacturing and service industry in the study area. Secondly, it draws the datum line of the urban fringe as the keynote and reference line of the fringe area based on industrial structure character. Thirdly, it draws the inside and outside boundaries of the urban fringe by defining the directional spatial auto correlation coefficient to identify the mutational site of industrial distribution. Finally, the method confirms the area of the urban fringe by combining the absolute value of employed population density of manufacture and service industry. The case study of Beijing City shows that the urban fringe of Beijing City is a discontinuity belt of different widths surrounding the Beijing central city. Its average width was 11 km in 1996 and widened to 13 km in 2001. Its area is about 2.5 times larger than that of the central city. The urban fringe of Beijing City moved 2.5 km away from the central area since 1996 to 2001 and every direction reached more and more equilibrium with each other. But the process of ringed expansion would tend to the limit. The sectorial expansion towards south and east will be the main trend of the spatial development of Beijing central city in the future.

Key words: urban fringe, spatial identification, industrial activities, Beijing