以江苏省为例,选取人口数及人口密度为研究指标,以县域为研究单元,通过人口密度、空间自相关、不均衡指数、重心移动及偏移—分享分析,描述20 世纪90 年代以来江苏省人口空间格局及其演变趋势。结果表明:近20 年来,江苏省人口密度有“南高北低”的特征,该现象与经济发展水平相对应;江苏省人口分布存在一定的空间关联性,在长江中下游各县市形成空间人口密度高的集聚区域,在苏北平原形成空间人口密度低的集聚区域,随时间推移人口集聚趋势不断减弱;江苏省人口呈不均衡分布状态且不均衡趋势加强,人口重心逐渐向西北方向迁移;江苏省人口增长速度在变慢,集聚人口能力在3 大区域之间有明显差异,苏中相对不足,苏南不断增强而苏北不断减弱。

The core driving force of urban development is the growth of population, while the spatial-temoral structure of the distribution of urban population is one of the theoretical frontier issues. This paper, taking Jiangsu Province as an example, describes the spatial pattern and evolving trend of the diverse population of Jiangsu with data at county level since the 1990s through the related analysis of spatial autocorrelation analysis, population gravity center model and shift-share analysis, as well as other tools such as population density and unbalanced index. Based on three time discontinuity surfaces, with software platform of ArcGIS and GeoDA, some conclusions are drawn as follows. (1) Population density of Jiangsu Province has“low-south and high-north” features, which are corresponding with its economic development level. (2) There is certain spatial relevance on population distribution in Jiangsu. The similar areas cluster in space. And this trend is receding as time goes by. Because of the higher economic development level, people gathered to the Yangtze River downstream counties, to form a high-low area. Counties between high-high area and low-low area become a low-high area due to less radiation from developed cities. Densely-populated area is distributed along the Yangtze River. The general pattern remains relatively stable, and the counties in the high-high area firstly increase and then decrease while counties in the low-low area continue to decrease. (3) The population distribution in Jiangsu is imbalanced and such situation is enhanced. The population gravity center slowly moves to the northwest of Jiangsu since 1990. (4) The population of Jiangsu is growing at a slow rate in recent 20 years. Population concentration ability is not alike in the three regions of Jiangsu Province. Central Jiangsu is short of clustering people and the population concentration ability of Southern Jiangsu constantly strengthens but that of Northern Jiangsu weakens.