绿洲型城市空间扩展的模拟及多情景预测——以酒泉、嘉峪关市为例

The Simulation and Multi-scenario Forecast of Urban Spatial Expansion in Oasis Cities——Take Jiuquan and Jiayuguan Cities as Examples

论文基于1987、1995、2000、2006和2011年多时相TM、ETM卫星遥感影像数据,以典型绿洲城市酒泉市和嘉峪关市为研究对象,运用目前较为成熟的集成元胞自动机模型(CA)和人工神经网络模型(ANN)的土地转换模型(LTM),依据干旱绿洲区城镇发展特点及趋势,设置自然增长、酒嘉一体化、集约增长和生态保护情景,对城镇空间扩展进行模拟预测。结果表明:运用LTM模型对研究区1987年以来的城市扩展进行模拟,具有较好的模拟精度和可靠性,可以用于未来研究区城市空间扩展的预测;酒泉市中心城市未来扩展的重点在南部和西部,嘉峪关市中心城市未来扩展的重点在南部和东部,两市相向发展进程进一步加快,城市一体化趋势明显;受区域一体化及生态保护战略的影响,论文设定的酒嘉一体化、生态保护及集约增长情景模式能较好地反映研究区未来城市空间扩展的主要趋势;在自然背景和开发现状的基础上,以政府战略决策驱动为主的方式是绿洲型城市空间扩展的内在机理。

With the rapid progress of urbanization in China,the urban space expanded rapidly.The establishment of urban spatial process dynamic simulation system is a popular research theme in the field of geography space which can simulate the typical regional urban development and explore the development and expansion trend of cities under different conditions.Based on the multi-temporal Landsat TM and ETM satellite remote sensing data of 1987,1995,2000,2006 and 2011,we studied the cases in two typical oasis cities： Jiuquan and Jiayuguan.Using the integrated cellular automata model（CA）,artificial neural network model（ANN） and Land Transformation Model（LTM）,the trends and characteristics of urban development were studied in different scenarios of intensive growth,integrated growth of Jiuquan and Jiayuguan,and ecological protection.The results show that： 1） The LTM model has good accuracy and reliability in simulating urban expansion that the Kappa coefficient and PCM index for Jiuquan City were 0.581 and 59.57%,and Jiayuguan City were 0.593 and60.20%,respectively.It can be used for forecast of future urban space expansion in the study area.2） Three scenarios were comprehensively analyzed,combined with the master plans of Jiuquan City and Jiayuguan City.The future expansion of Jiuquan City will be in the south and the west.The future urban expansion of Jiayuguan will be in the south and east.The two cities expand towards each other speedily and there is an obvious trend of urban integration.3） Under the influence of the regional integration and ecological protection strategy,the scenarios of Jiuquan-Jiayuguan urban area integration,ecological conservation and intensive growth can better reflect the future urban expansion in the study area.The Kappa coefficient and PCM index of Jiayuguan City were as high as 0.721 and 73.07%,respectively,and the Kappa coefficient and PCM index of Jiuquan City were 0.666 and 68.40%,respectively.Compared with the natural growth scenario,the expanded urban area of Jiuquan City under intensive growth and ecological protection scenarios decreased 9.39% and 9.38% in 2020 and 2030,and that of Jiayuguan City decreased 9.47% and 10.89%,respectively.4） The government＇s strategic decision-making is the main driving force of the urban space expansion,which determines the main direction of the expansion of oasis-type cities in the future.Therefore,on the basis of natural background and current situation of development,government-driven decision-making is the internal mechanism of oasis-type urban expansion.