Modelling Urban Population Densities in Beijing 1982-90: Suburbanisation and its Causes

The existing empirical research of urban population density is rich on developed countries but much less so on developing countries. On cities in a planned economy such as that of China, very little is reported. Part of the reason is the lack of reliable data sources. This research models the population densities in Beijing 1982-90. Data are from the third and fourth national population censuses in 1982 and 1990 respectively, and are aggregated at the level of sub-district (jie-dao). Spatial boundaries of these sub-districts are obtained from various sources of local governments and numerous field trips. The research shows that the negative exponential function also fits the density distributions in Beijing, the density gradient becomes flatter, and the city-centre intercept drops over time. The results are consistent with the findings on Western cities, implying that even a socialist city cannot escape the universal forces shaping urban structure. In addition, GIS surface modelling is used to analyse the spatial patterns. While central-city sub-districts have experienced significant loss of population, suburban sub-districts have gained growth at various scales. This signals the beginning of suburbanisation in Beijing. However, some of the causes are different from those in Western countries.