近25 a甘肃省人口分布的时空格局及影响因素

人口分布是在一定时间、一定地域范围人口在空间上的表现，它会受社会、经济、自然和政策等多种因素影响，甘肃省人口分布处于不平衡状态。以甘肃省86个县域及嘉峪关市共87个研究单元为对象，常住人口数据为基础，对研究区1990—2015年之间人口的分布特征、密度变化、分布结构指数、基尼系数、重心迁移等时空格局变化进行了分析。以县域为研究单元，选取12个自然和社会经济因素，利用偏最小二乘法（PLS）对影响甘肃省人口分布空间格局的因素进行分析。研究发现：（1） 近25 a来甘肃省人口空间分布差异显著，形成“东南密集西北稀疏”格局；（2） 从人口密度变化来看，相较于1990年，2015年甘肃省87个研究单元中，有67个县域属于增加类型，20个县域属于降低类型；（3） 全省人口分布的均衡性发展态势在增强；（4） 人口分布的重心逐渐向西北方向迁移；（5） 甘肃省人口分布格局的形成受自然因素与社会经济因素的同时影响，但社会经济因素影响最大。

Spatiotemporal patterns of population distributions and influencing factors over 25 years near Gansu Province

Population distribution is affected by natural,social,economic,and political factors,which are manifestations of the spatial distribution of a population over a certain period of time.Based on 87 research units in 86 counties and Jiayuguan in Gansu Province,China,the distribution characteristics,density change,distribution structure index,Gini coefficient,and gravity transfer of the study area from 1990 to 2015 were analyzed.Considering the county area as the research unit,12 natural and socioeconomic factors were selected and the factors affecting the spatial patterns of the population distribution in Gansu Province were analyzed using the partial least squares (PLS) method.The study found as follows:(1) Over the past 25 years,there have been significant differences in the spatial distribution of the population in Gansu Province,which have formed a pattern of “sparse in the southeast and northwest”.(2) From the perspective of population density changes,when compared to 1990,among the 87 research units in Gansu Province,67 counties in 2015 belong to the rapid increase and slow increase types and 20 counties belong to the rapid reduction and slowdown types.(3) The development trend of a balanced population distribution for the entire province has increased.(4) The center of gravity of the population distribution has gradually moved in the northwest direction.(5) The formation of population distribution in Gansu Province is affected by natural and socioeconomic factors; however,the level of social and economic development is the main factor affecting the population distribution patterns.