Relationship between the degree and spatial pattern of urban shrinkage based on nighttime light data: a case study of the old industrial area in Northeast China

Urban shrinkage is a common phenomenon worldwide, but the relationship between the degree and spatial pattern of urban shrinkage is unclear. This paper takes the old northeastern industrial base, a region with a concentration of shrinking cities in China, as the study area. With the help of multi-source remote sensing images, this study first identified the degree and spatial pattern of urban shrinkage, and then investigated their relationship using the chi-square test. A total of 63 physical urban areas were identified as shrinking cities during the period 2013–2018. Among them, the proportion of cities with moderate and severe shrinking was relatively high. The spatial patterns of urban shrinkage are classified as central shrinkage, peripheral shrinkage, perforation shrinkage and global shrinkage. The results of the chi-square test proved that the spatial pattern and degree of urban shrinkage are correlated. Mild shrinkage was usually peripheral shrinkage; moderate shrinkage was usually central and perforation shrinkage; and severe shrinkage was usually global shrinkage. Identifying the degree and spatial pattern of urban shrinkage and investigating their relationship help deepen the understanding of the urban shrinkage phenomenon at a theoretical level and help urban planners and policy makers propose multidimensional strategies to alleviate the development dilemma of shrinking cities on a practical level.