The Relief Degree of Land Surface and its Correlation with Population Distribution in Urban Agglomerations of China

Based on the macro-scale digital elevation model data, by using ARC/INFO software, the relief degree of land surface (RDLS) of 10 kmtimes10 km grid size is extracted and mapped in urban agglomerations of China. Then this paper systemically depicts the distribution rules of RDLS in urban agglomeration and its correlation with population distribution by analyzing the ratio structure and spatial distribution. The conclusions are drawn as follows: the RDLS in more than 72% of the area is less than one (1) (relative altitude is less than 500 m), reflecting the fact that most of RDLS in urban agglomeration of China is low. In general, the RDLS in the west is larger than that in the east and so is the south than that of the north in urban agglomeration of China. Analysis of the correlation between RDLS and population distribution in urban agglomeration and its regional difference shows that the R2 value between RDLS and population density is 0.81 and RDLS is an important factor influencing the spatial distribution of population in urban agglomeration. More than 88% of the people in urban agglomeration live in areas where the RDLS is less than one (1), while the population in areas with RDLS greater than 3 accounts only for 0.5% of the total.