Spatial Patterns of Built- up Ar eas around Beijing
北京周围建设用地空间分布格局及解释

The urban effect on land use pattern is always one of the key fields of geographical science. The ratio of built-up areas is very high around a large city, so it is important to analyze and explain the patterns of built-up areas around the city, which may be helpful for understanding the effect. Through building five buffers from inner to outer parts around Beijing, this paper discusses the pattern of built-up areas of Beijing, and explains the pattern from the natural, historical, and economic aspects. The main conclusions include: 1) there are four belts with higher density of built-up area, which is in accord with "horse road" of the Qin Dynasty in BC 200; 2) the continuity of spatial distribution of built-up areas is not interrupted by the division of administration; 3) buffer between 30 and 40 km may be the borderline of urban effect on the plane surface, although the effect can touch some farther regions through transportation lines; and 4) there are two peaks of urban land shares in the buffers between 10 and 20 km, and between 30 and 40 km.