以不同时段的Landsat TM/ETM卫星遥感图像为数据源,利用G IS技对东莞市城镇用地的时空特征:扩张面积、扩张速度、扩张强度指数和土地利用转移矩阵进行了分析;另外,结合社会经济统计数据对东莞市城镇用地扩张驱动力作了分析。研究结果表明:近15年来,东莞市城镇用地面积扩张了近7倍,尤其是1988-1995年,扩张趋势最为明显;在不同象限和时段上扩张强度和规模差异较大,且空间分异明显,扩张以东北和西南方向为主。东莞市城镇用地扩张主要侵占的是耕地和开发用地,1995年后侵占主体由耕地转变为开发用地,表明扩张方式发生了改变。经济发展是东莞市城镇用地扩张的决定因素,同时,相关政策指引着经济发展的方向,贯穿于东莞市城镇用地扩张的全过程。
This paper takes Dongguan City which is in the Area of Pearl River Estuary as an example.Under the strong trend of urbanization and industrialization,affected by both natural and artificial factors,the urban land expansion and the changes of landscape pattern continued year by year.Applying satellite images of Landsat-TM and integrating techniques of remote sensing imagery processing and GIS,the present study analyzed temporal and spatial process and driving factors of urban land expansion in Dongguan City from 1988 to 2002.The characteristics of urban land expansion are identified by several methods in analyzing the spatial-temporal features of Dongguan City from 1988 to 2002,which include expansion area,expansion speed,expansion intensity index and transformation matrix index.The main results are as follows:(1) during the last 15 years,area of construction land has been almost sevenfold which is more obvious during the 1988-2002 period.(2)The urban land expansion in different districts was obviously diversified and the main directions of urban land expansion are northeast and southwest.(3) The main types occupied by urban land expansion are arable land and developing land,the changes in the main occupation before and after 1995 as the result of the differences of the factors such as policies and economy,but in general the occupation of arable land is still the largest number in all landscape types.(4) The driving force of urban land expansion and its comprehensive evaluation are given in this paper using social economical data and correlation analysis.The economic growth is the decisive factor influencing the urban land expansion,and the correlative policies direction the economic growth run through the urban growth from beginning to end.