Redai dili (May 2023)
Spatial and Temporal Analyses of the Expansion of Built-Up Areas in Nanjing Metropolitan Area Based on Industrial Big Data
Abstract
With the integrated development of the Yangtze River Delta as a national strategy, urban development in the Nanjing metropolitan area has entered a new stage. However, facing the large differences between the newly joined districts and counties are the key issues of ensuring the driving role of Nanjing as a central city and guiding future high-quality development of the metropolitan area by planning the industrial layout. In this study, enterprise big data and impervious surface data were used as the sources to employ fractal theory, GIS spatial analysis, and other techniques to study the historical evolution characteristics of the built-up areas in the Nanjing metropolitan area. The spatial pattern changes of their expansion intensity have gone through three periods: 1990-2000, 2000-2010, and 2010-2017. The following stages were observed:1) In the first stage, the expansion intensity varied widely across the area with the overall pattern being unclear to date. 2) In the second stage, a circular structure emerged gradually with high-value cores located in the main downtown area of Nanjing and the intensity of expansion decreasing from the core to periphery. 3) In the third stage, the number of cores within the circle gradually increased to include Chuzhou Langya District, Huaian Qingjiangpu District, and the border area between Zhenjiang and Changzhou. Based on these stages, the spatial correlation between industrial agglomeration and spatial evolution of built-up areas in the Nanjing metropolitan circle were further analyzed using quantitative indicators such as the Moran index and locational entropy. The following results were obtained. 1) A global positive correlation was observed between the agglomeration degree of manufacturing industries in the metropolitan circle and the spatial evolution intensity of built-up areas during 1990-2015; however, this global-level correlation has decreased in recent years owing to the slower development of manufacturing industries in some regions than the expansion of built-up areas. 2) The structural differences between the manufacturing industries in each region directly influenced the intensity and speed of built-up area expansion. Additionally, different types of manufacturing transfers caused differences in the speed and intensity of expansion of built-up areas in the hinterland of metropolitan circles, affected by the general trend of industrial division of labor in metropolitan circles. 3) The mineral processing industry showed the widest spread among all labor-intensive and low value-added industries. It also possessed the widest diffusion range and played a driving role in the development of built-up areas in each district and county in the long term, whereas for the remaining industries, the initially strong development of built-up areas weakened thereafter. Therefore, it could be argued that the Nanjing metropolitan circle is in a critical period of coordinated regional development, and the initiatives to transfer low-end manufacturing industries to other regions in the circle must be taken in Nanjing while continuously improving its own supremacy by means of collaborative development and innovation. Simultaneously, the sloppy land resource investments in other regions must be altered to improve efficiency.
Keywords
