Li Yingcheng, Zhong Xiaohan, Qi Junheng, Hu Mingxing

Keywords： Building Density; Spatial Growth; Negative Exponential Function; Urban Sprawl; Sustainability

Abstract：

Building density is one of the important indicators to measure urban spatial density, and its intracity distribution pattern could to some extent reflect a city’s spatial growth features at the horizontal scale. Therefore, it is of great significance to explore the distribution law of intra-city building density to reveal the basic characteristics of urban spatial growth and formulate planning strategies to promote sustainable urban growth. In this paper, 287 cities at the prefecture level and above in China are taken as research samples, and the building density data in 2000, 2010 and 2020 at the 100-meter grid scale are used to construct the urban peripheral growth index based on the gradient analysis of building density in concentric rings from the urban center. The index is utilized to study the spatial growth features of the sample cities and the main conclusions are as follows: (1) The distribution of urban building density gradually decreases from the center to the periphery, which can be better fitted by negative exponential function; (2) Most of the cities in 2000-2010 and 2010-2020 show the features of increasing peripheral growth. The increasing peripheral growth index from high to low is in the order of big cities, medium-sized cities, super- and mega- cities, small cities, while that of the small cities is not statistically significant; (3) Natural geographical conditions, population and economic
scale, macro-policy and planning guidance are important factors affecting urban spatial growth features and the discrepancy of cities of different scales.

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