Spatio-temporal evolution of migration in China from 1995 to 2015

Abstract

Based on the data of usual residence from 2000 and 2010 censuses and 1995 and 2015 micro-censuses and using the method proposed by Abel G. J., this paper estimates the O-D migration flows among prefectural-level administrative units in China for the period 1995-2015. By using the indicators of migration flows and migration rates, and the methods of GIS spatial analysis and community detection in social network analysis, it further reveals the characteristics of spatio-temporal evolution of migration in China since 1995. The results can be summarized as follows. (1) The scale and intensity of migration in China have been increasing, while their differences among regions have been gradually decreasing. This suggests that migration has experienced a gradual transformation from a "low-activity era" including a limited number of regions to a "high-activity era" involving the majority of regions. (2) Six regional types of migration among prefectural-level administrative units, namely, large-scale active net in-migration, small-scale net in-migration, large-scale active net out-migration, small-scale active net out-migration, active balanced migration and inactive migration, are identified. The spatio-temporal evolution characteristics of the regional types of migration in China indicate that each active migration regional type has been undergoing a change of continuous diffusion, while the inactive migration regional type has seen a significant reduction over time. (3) The spatial patterns of migration are quite different between regions on both sides of "Hu Line", manifested in the fact that the scale and intensity of migration flows on the southeastern side of the line is higher than that on the northwestern side, which means that the "Hu Line" is quite stable and robust in the last 20 years. (4) Patterns of migration flows indicate that while intra-provincial migration has continuously strengthened, inter-provincial migration has exhibited more complicated spatial patterns, mainly reflected in different changing trends of attractiveness to migrants among the three coastal city clusters, and the increasing migration flows within southwest China. As a result of combined effects of inter- and intra-provincial migration flows, the structure of migration flows in China's eastern, central and western regions has been undergoing changes, resulting in the internal differentiation of urban agglomerations and the declining spatial scope under their influence in the coastal areas, Hubei as the single independent "city community" in central China, as well as the relative stability in northwest China and continuous change in southwest China.