Quantifying spatiotemporal patterns of urban expansion in three capital cities in Northeast China over the past three decades using satellite data sets

Urban expansion is probably the most drastic form of land conversion and its impacts far transcend city’s physical boundaries. Many studies have documented China’s rapid urban expansion while the urban expansion in the traditional industrial base in Northeast China was understudied. Based on multi-temporal remote sensing images and landscape metrics, this study characterized the spatiotemporal patterns of urban land use changes in the metropolitan regions of three capital cities (i.e., Shenyang, Changchun and Harbin) in the Northeast China’s traditional industrial base over the past three decades. The urban land in Shenyang, Changchun and Harbin expanded from 209.8, 202.0, and 239.6 km²in the late 1970s to 836.3, 682.4 and 567.9 km²in 2010, with an annual growth rate of 4.6, 4.0 and 2.6 %, respectively. The newly developed urban lands were largely distributed around the edge of urban districts. For all cities, the edge expansion was the dominant urban growth type (>50 %), followed by infilling growth, and the proportion of outlying growth type was relatively low (