Spatial analysis of urban compactness in China

As a sustainable development strategy that advocates higher urban land use efficiency, compact urban development is of great importance to China´s cities which face a great deal of problems at the stage of rapid growth, such as the sprawl of construction land, the short supply of housing residents in urban areas, and incompatible relationship between urban and rural areas. To interpret the spatial-temporal characteristics of China´s cities, the comprehensive evaluation index system is built up based on six dimensions: land-use compactness, economic compactness, population compactness, infrastructure compactness, public service compactness, and eco-environment coordination. Entropy methods were used to calculate the weights of each evaluation index, and then the urban compactness of 280 cities was calculated at the prefecture level and above in 2001, 2005 and 2009 based on those weights. The result showed that urban compactness elevates slightly overall, and the disparities between cities decreases gradually, which the high scores of urban compactness grow small and the low score of that promote slightly. As to the spatial pattern of urban compactness, the eastern part ranks highest, and is followed by the central part and western part of China, which implies the score of urban compactness is relative higher in east and relative lower in west, and that spatial pattern is similar to the spatial pattern of regional economic development. It is obvious to notice the spatial heterogeneity of urban compactness; Moran´s I statistics within entire research periods are completely positive, although it gets stronger, urban compactness´s spatial interaction is weak. H-H type mainly locates in coastal areas, such as Beijing-Tianjin-Hebei area, Yangtze River Delta and Pearl River Delta.