Investigating sprawl along China’s urban fringe from a spatio-temporal perspective

Compared to the urban sprawl in western countries, China’s version varies, although it retains a dispersed development pattern, which is an important feature. A new framework is provided in this paper to allow for a deeper understanding of China’s spatio-temporal sprawl patterns along its urban fringes. In this framework, Shannon’s entropy analysis and discontinuity index have been employed to quantify the spatial patterns of urban sprawl. Furthermore, a new approach, Spatial Change Frequency Analysis (SCFA), has been proposed in this paper to analyze the temporal patterns of urban sprawl related to individual pixel based on multi-temporal Landsat TM images. With two indicators, namely Spatial Change Frequency (SCF) and Spatial Change Intensity (SCI), this approach appears to effectively reveal the abnormal land use changes in the urban fringes. Jiangning District of Nanjing City, Jiangsu Province, a fast growing urban area, was selected as the study area due to its unique characteristics of urban fringes. The results indicate that the effectiveness of urban land-use planning and implementation of land-use planning policies play important roles in mitigating the negative effects of urban sprawl. Finally, some suggestions are proffered to support sustainable development at the urban fringes of Nanjing City.