The population dynamics in China: understanding the role of spread and backwash effect

Considering the declining population growth and increasing intra-provincial migration in China, the population issue becomes crucial for the sustainable development of the Chinese economy. We utilize data of 2010 and 2020 China Census to study the impact of the “spread-backwash” effects of large cities on county-level population dynamics over the past decade and investigate the potential mechanisms. We find that the spillover effects generated by cities have significantly increased the population of neighboring counties. Regarding the mechanism, the “spread-backwash” effects of large cities facilitate the integration of county-level secondary industries into urban industrial chains, leading to new enterprise investments and job creation. In counties where spillover effects are significant, the number of new enterprises in the tertiary industry is higher, positively impacting local population growth.