北京城市人口空间分布特征的GIS分析

Analyzing Urban Population Spatial Distribution in Beijing Proper

城市人口空间分布特征分析是城市化影响下的局地尺度人类-环境（Human-Environment）相互作用研究的一个重要内容。本研究以第五次人口普查数据,采用GIS网格计算方法,模拟北京市2000年人口空间分布,并从宏观、微观、中观3个不同层次分析其空间分布与变异特征。研究表明,从宏观角度分析,各环路间人口密度具有较大的差异,自内向外整体上呈现先增加后减少的态势;从微观角度分析,人口分布具有高度的集聚性和空间自相关性,小尺度变异在全局变异中所占的比重较小,表现出良好的整体结构特征;从中观角度分析,人口密度从城市中心向外围呈现阶段波动性递减特征,在0~8.5、8.5~13.5、13.5~33.0km范围内分别符合抛物线模型,各段内人口密度在小距离增加后表现出长距离的减少趋势。城市空间结构分布所呈现的＂单中心波浪散射＂布局模式,显著区别于国外经典的城市人口空间结构。

Analysis of urban population distribution due to urbanization at local scale is important contents in studying human-environment interaction.Based on the urban geographical information framework,in this research we used the fifth population census data of 2000 and urban building spatial data extracted from aerial photos,to simulate population spatial distribution with 300m-gird using GIS grid technology.Then we analyzed population spatial distribution and variability at different scales.The results indicated that,from the macro-view analysis,the ring-roads system had a significant influence on population distribution,that is,considerably different densities among the ring roads with integral decreasing gradients from inner- to out-ring roads.From the micro-view analysis,population distribution had spatial agglomeration and autocorrelation.The micro-scale variation accounted for less proportion in the whole variation.From the middle-view analysis,population distribution appeared strong step-down fluctuations from the city center to the periphery.Within the ranges of 0-8.5,8.5-13.5 and 13.5-33.0 km,population density showed parabolas with downhill hatch.Meanwhile,population density showed a reduction trend for a long distance but an increase for a short distance.So we concluded that population spatial distribution in Beijing had ＂single-center and Scattering wave＂ characteristics,a distinct difference comparing to other urban population distribution.