Unveiling the Regional Differences and Convergence of Urban Sprawl in China, 2006-2019

There is an obvious imbalanced regional development among eastern, central, and western China. This is also a fundamental problem that policy makers and planners need to address. Specific to urban development, we wondered whether there were regional differences in urban sprawl and whether this trend was under control. By using the urban sprawl index (USI), this paper investigated the spatiotemporal pattern of urban sprawl from 2006 to 2019, and its regional difference and convergence among eastern, central, and western China. It finds that the cities with high, medium, and low sprawl in the east and west regions are distributed with a clear geographical pattern, while the distribution in the central region has no intuitive geographical features. Also, the proportion of cities with high sprawl in the eastern region is more than that in the other regions, with low sprawl in central China and medium sprawl in the western region. Moreover, urban sprawl in all three regions showed a downward trend, but this process was fluctuating and had obvious phase characteristics. It can be concluded that there is a convergence trend in urban sprawl in China over the research period, and the club convergence effect exists in the eastern, central, and western regions.