Spatiotemporal variation analysis of driving forces of urban land spatial expansion using logistic regression: A case study of port towns in Taicang City, China

Abstract Understanding the driving mechanisms of urban land spatial expansion (ULSE) is crucial for the guidance of rational urban land expansion. Previous studies have primarily focused on single large cities, with few explorations of the spatiotemporal differences in driving forces of ULSE of different towns in the same administrative region. This study aims to fill this gap. Three port towns of Taicang, located in China's Yangtze River Delta region, were taken as examples to analyze the expansion process of urban land during 1989–2008. Eight factors, including ecological suitability, prime croplands, etc., were selected from four aspects of natural eco-environment, land control policies, accessibility and neighborhood. Binary logistic regression was employed to investigate the effects of various factors on ULSE during various periods in different regions. Results reveal that over the past two decades, urban land expanded rapidly in the three towns, but with different expansion speeds and growth rates. Diversified ULSE factor combinations exist during different periods in different regions, and the factors' relative importance also varies with time and space. The four types of driving factors simultaneously affect ULSE, among which the accessibility is dominant. Based on the findings, we suggest that differentiated policies should be formulated to guide reasonable expansion of urban land. This study can help us better understand the driving mechanism of urban land expansion in small cities and towns, thus has important implications for urban planning and management in China and similar countries.