Urban Spatial Structure of Karst City:A Case Study of Guizhou Province

Guizhou is a province,where karst accounts for 73﹪of its total area,the largest proportion in the provinces of China.Cities and towns are distributed in the basin which make up only 3﹪ of the total land area.They have special urban spatial configuration as a result of unique physiognomy condition.On the one hand,the cities and towns have beautiful landscapes with unique mountain-water characteristics;on the other,the urban space is limited by the landform,so the urban scale is small correspondingly,their function are mixed and the duality structure between city and country is obvious.According to the urban spatial formation,dominant functions,driving power and outspread direction,the urban spatial structures and formation are studied,and 12 karst mountainous cities in Guizhou are classified into 5 types: group mode,circle with Greenland heart mode,belt-shape city mode,agglomerate mode and string radiation mode.Some aspects on the spatial structure of karst cities are consider worthy of study.