Research On Spatial-temporal Evolvement Of Urban Compactness And Urban Efficiency In China Based On The Model Of ESDA And DEA

It is such a fast growing process that the urbanization in china evokes manyproblems, like land use expansion and insufficient urban efficiency, and it makes thesustainable development for urban area much harder. As a sustainable developmentstrategy, compact city favors a city with high efficiency, intensive structure andoptimized function, which should orients lots of policies and advices to those fastgrowing cities in china. This paper takes two hundred eighty cities in china which areat least prefecture-level cities as research units at the year of2001,2005and2009.Urban compactness evaluation index system was formed, then spatial-temporalevolvement of urban compactness was analyzed from the perspective ofregion-oriented division and scale-size oriented division, and spatial-temporalevolvement of urban efficiency was analyzed too, then the relationship between urbancompactness and urban efficiency was analyzed by quadrant plots.The urban compactness evaluation index system was structured upon sixdimensions which are land use compactness, economic compactness, populationcompactness, infrastructure compactness, public service compactness andeco-environment coordination. Weights of those dimensions were calculated bymaximum entropy method and those of economic compactness(EOC) and ecologyenvironment coordination(EEC) are relative high, which implies that cities in chinaare at economic transition periods that is trying to switch from traditional extensivedevelopment form pattern to intensive and eco-friendly sustainable developmentpattern.Some characteristics are drawn from the analysis of spatial-temporal evolvementof urban compactness, which includes that the overall disparity gets smaller andsmaller, and the spatial aggregation of urban compactness increase in fluctuation withdifferent dimension compactness varying in evolvement of spatial aggregation. H-Hand L-L type is the major type of spatial interaction types with spatial interactiongrowing a little stronger. As to the different compactness levels of cities, themiddle-level cities take a majority part and the high-level and low-level citiesdecrease. The high-level compact city mainly locates in coastline area and the areawhich the Beijing-Guangzhou railway covers. As to the region oriented division, thecompactness level of eastern plate is much higher while the middle plate, westernplate and northeastern plate are relative low, and the compactness level of middle and western plate increases. Different dimension compactness display different impact ineach region and the disparities among the regions is the main reason of disparity ofregion oriented division. As to the scale-size oriented division, it shows that when thelevel of scale-size is high, the urban compactness is high.The urban compactness ofcities which are above the level of medium-scale decrease, while those of below thatlevel increase. Different dimension compactness do not display similar influence ineach scale-size and the inner disparities and amongst of the scale-size decrease.Urban efficiency are calculated by ultra efficiency DEA method and its resultsshow that the urban efficiency of china is low overall and the distribution of urbanefficiency shows a polar feature which majority cities has a low value of urbanefficiency. As to the region division of urban efficiency, it shows the spatialdistribution of urban efficiency is consistent with the development pattern of regioneconomics which the eastern plate is high and the other plates are relatively low. Withrespect to the evolvement of urban efficiency, most regions decrease between2005and2009. As to scale-size oriented division, it shows a U curve pattern that the urbanefficiency of giant cities, megacities and small cities is high and that of big cities andmedium cities is relatively low.The relationship of urban compactness and urban efficiency are divided into fourcategories by quadrant plots, hence two hundred eighty cities fall into each categories,in that way it shows the overall type of china cities is low coordination category,which is low-low condition that implies both of the urban compactness and urbanefficiency are low. While, the cities of eastern plate display a significant highcoordination category which is high-high condition and the other three plates ismainly in low-low condition. When the level of cities of scale-size is high, thehigh-high condition is more obvious, and the cities in china have come through theprocess of low coordination period, under-compact period, over-compact period andhigh coordination in general.