传统单中心与组团城市的空间重构模式对比与特征差异

Pattern Comparison and Characteristic Disparity of Urban Restructuring Between Traditional Mono-centric City and Group City

选取山东省双核心城市——传统单中心城市济南和组团城市青岛,对其城市空间重构模式和特征作对比研究。借助ArcGIS9.0空间分析和空间统计功能,对研究时期内城市空间形态演变、用地扩展、人口和生产力空间分布变动等各种空间特征指标进行测量和比较,构建用地与人口异速增长模型、人口空间分布模型和基于空间基尼系数的生产力分布模型。研究表明:①济南和青岛正在经历完全相异的空间演进过程,即济南由单中心向东西组团式分散扩展、青岛组团式发展空间被不断填充连片而趋向紧凑;②两个城市用地扩张、人口分布以及投资、就业分布边缘化的趋向表明,单中心城市扩张的集约度更高,但未来用地供给也易受到城市形态制约,可持续度较低,城市未来发展可能会在一定程度上经历投资和就业空间失配带来的效率损失;③在空间重构模式的选择方面,青岛应当选择重点区域集中开发的发展模式,而济南选用城市用地结构调整的策略要优于城市用地规模扩张。

Jinan and Qingdao were selected for empirical comparison as the two representative cities showing perceived diversity of urban restructuring patterns and characteristics, in the way of polycentric groups pattern of Qingdao compared to monocentric pattern of Jinan. Based on AreGIS 9.0 spatial analysis and spatial statistic model, land-population model complying with allometric law, spatial distribution model of population density and productivity distribution model indicated by spatial Gini coefficient, were constructed to describe and measure differences of various spatial index, for instance, urban form evolution, land expansion, and variation of population and productivity spatial distribution. Based on above analysis, we could come to some conclusions. （1）Dissimilar tendency of spatial evolution is occurring in Jinan and Qingdao; Compared with compact pattern of Qingdao from polycentric groups to internal infilling, Jinan is experiencing dispersed pattern from monoeentric pattern to eastern and western groups. （2）Land expansion, population migration and marginalization trends of investment and employment distribution in the two cities show that mono-centric city has more intensive urban expansion than polycentric city. However, land supply in this type of cities is usually restricted by urban form, which is characterized by lower sustainable degree and would experience efficiency loss in a certain degree originating from mismatch between investment space and employment space. （3） Qingdao should choose centralized and continuous developing pattern in key areas, while policy of land structure regulation rather than land expansion should be taken into consideration in Jinan.