贵州省城镇建设用地扩展的时空演变特征

选择贵州省的85个城镇为研究区,运用1973年1∶5万地形图,1986、1995、2000和2007年4期高分辨率遥感影像,选取城镇扩展动态度指数、城镇扩展贡献率指数和城镇扩展强度指数3个指标,构建城镇综合扩展程度指数模型,定量分析了1973—2007年4个时期贵州省城镇建设用地扩展的总体特征和时空分异特征。结果表明:从1973—2007年,贵州省城镇建设用地呈持续增长态势,城镇建设用地面积共增加17550.8915hm2,其中2000—2007年贵州省城镇建设用地扩展面积最大,动态度、贡献率和强度指数均最大;研究区建设用地扩展具有明显的空间分异特征,1973—1986年,城镇建设用地扩展主要集中在省会城市贵阳市,1986—1995年,地级城市所在城镇扩展面积和强度快速提高,1995—2000年,交通沿线城镇扩展速度加快,2000—2007年,贵州省城镇扩展强度和综合扩展程度不仅在贵阳市和地级城市较快,而且在区位和自然条件良好的县级城镇也迅速提高。

Spatiotemporal evolution of urban and town' s construction land expansion in Guizhou Province of Southwest China

Selecting 85 cities and towns in Guizhou Province as study areas and using the topographic map (1∶50000) in 1973 and the Landsat TM satellite images in 1986, 1995, 2000 and 2007, an urban and town’s integrated expansion degree index model was established by the use of the indices (expansion dynamic degree, expansion contribution rate, and expansion intensity), and the overall spatiotemporal characteristics of the urban and town’ construction land expansion in the Province from 1973 to 2007 were quantitatively analyzed. In the Province in 1973-2007, the area of urban and town’ s construction land increased continuously, with a total increase of 17550.8915 hm2, and the expanded area, expansion dynamic degree, expansion contribution rate, and expansion intensity reached the maximum in 2000-2007. Furthermore, the construction land expansion in the Province had an obvious spatial differentiation. In 1973-1986, the construction land expansion was mainly in the provincial capital Guiyang City; in 1986-1995, the expanded area and the expansion intensity of the construction land increased rapidly in prefecture-level cities; in 1995-2000, the expansion of the cities and towns along transport lines was speeded up; and in 2000-2007, the expansion intensity and integrated expansion degree increased not only in Guiyang and prefecture-level cities, but also in the county-level cities and towns with good geographical locations and natural conditions.