Abstract: The spatial distribution of population presents different features as the scale varies. Studies on the effect of natural resources on urban population distribution on the scale of street and township could provide more precise results. This research aims to provide a scientific foundation for reasonable population distribution arrangement and urban planning. Based on the data of the fifth population census and the sixth population census in Beijing on the scale of street and township, this paper analyzed the features of both the permanent residents distribution and the floating population distribution in Beijing by exploration of spatial data analysis with ArcGIS. The geographical detector was used to explore the effect of various zonal natural factors on the population distribution. The natural factors in our analysis which have been proved to influence the population distribution include the altitude, slope, relief degree of land surface, water system density, and suitable construction land. The results showed that: 1) The natural factors have different impacts on permanent residents and floating population distribution. The natural resources having effects on the permanent residents density were the suitable construction land (0.336), the relief degree of land surface (0.236), the slope (0.230), the altitude (0.182), and water system density (0.145) in descending order according to factor dictator of geographical detector. And the natural factors having impacts on the floating population density were the relief degree of land surface (0.260), the suitable construction land (0.246), the slope (0.227), altitude (0.197), and water system density (0.111) in descending order. 2) The natural factors had different impacts on the spatial pattern of population in different regions. For the regions both inside and outside the sixth express way loop, the suitable construction land was the most decisive natural influential factor. Besides the suitable construction land, the slope (0.191) was the second decisive natural influential factor to the population distribution in the regions inside the sixth express way loop, and the water system density (0.148) was the second decisive natural influential factor to the population distribution in the regions outside the sixth express way loop. These two natural factors had greater impact on the population density than other natural influential factors. The altitude had more profound impact on the population density in the regions outside the sixth express way loop (0.093) than they did to the regions inside the sixth express way loop (0.051). The P_DU value of relief degree of land surface on the population density in the regions outside the sixth express way loop was 0.125, larger than that of the regions inside the sixth express way loop which valued 0.009. 3) The result of interaction detector from the geographical detector showed that the overlay impact of two natural factors on population density got intensified, and the intensified effect was often presented as the synergy of two factors or the non-linear increase of two factors. The comprehensive impact of five natural factors on population density valued 1, which disclosed that the natural factors enhanced each other when they influenced the population distribution.

Key words: Beijing, geographical detector, population distribution