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

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 ArcGIS 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.①Dissimilar 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 monocentric pattern to eastern and western groups.②Land 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.③Qingdao 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.