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Urban spatial expansion of Xiangtan City, China

With the accelerating process of urbanization, Chinese government and relevant planning authorities pay much attention to the urban expansion. In this paper, Xiangtan City, in China, is chosen to be the typical city, and its central built-up area information, during 1973–2008, is extracted by using remote sensing and GIS techniques. Urban expansion characteristics of Xiangtan City are systemically analyzed by using many indices, such as urban expansion speed, spatial expansion fractal characteristic, urban expansion's impact on local land use, and so on. According to temporal and spatial characteristics, and corresponding driving factors of Xiangtan City in the past 25 years, BP-CA model is constructed by considering advantages of back propagation neural network and cellular automata model in urban expansion simulation and prediction. Spatial expansion of the urban land in Xiangtan City during 2010–2020 is simulated, evaluated and predicted. This study provides scientific master plan for land use and city.