Prefecture-level city shrinkage on the regional dimension in China: Spatiotemporal change and internal relations

City shrinkage characterized by population loss is a difficult issue challenging urban planning and regional development policy. China has been experiencing rapid urbanization over the past several decades. Although numerous studies have identified the characteristics and factors of urban expansion in China, city shrinkage has been widely ignored. This paper measured prefecture-level city shrinkage from the regional dimension based on the fourth (1990), fifth (2000) and sixth (2010) national census data in China. The spatiotemporal characteristics of shrinking cities were analyzed in different economic regions, and the relevant factors contributing to city shrinkage were explored based on the Pearson correlation coefficient. The results showed that the number of shrinking cities and the shrinking degree continuously increased from 1990 to 2010 in China. City shrinkage showed a significant positive correlation in space and was highly related to the regional economic level and population structure. Specifically, the aging population was a key factor responsible for city shrinkage, and a negative correlation was observed between the economic level and city shrinkage. These findings contribute to our understanding of the relationship between city shrinkage and economic development and provide important information for governments and planners formulating scientifically-based city development policies.