张掖市1985—2020年城区建设用地扩展时空演变研究

Study on Temporal and Spatial Evolution of Urban Construction Land Expansion in Zhangye City from 1985 to 2020

基于1985—2020年张掖市甘州区Landsat影像数据,对张掖市城区建设用地扩展时空演变进行定量化分析,并对其扩展合理性进行评价。结果表明,(1)1985—2020年,张掖市城区建设用地规模扩展迅速,可将其扩展划分为以下几个阶段:1985—1995年慢速扩展;1995—2000年中速扩展;2000—2005年快速扩展;2005年之后高速扩展。(2)城区建设用地扩展指向性强,扩展的主要方向以2010年为节点先集中在东北方向后转移到城市西部。(3)城区建设用地空间形态从较为不规则、不稳定的“条带状”转变为简单、稳定的“团块形”。(4)张掖市城区建设用地扩展与人口增长及经济发展之间协调性较差,城区建设用地扩展明显过快。

Based on the Landsat Image data of Ganzhou District,Zhangye City from 1985 to 2020,the temporal and spatial evolution of urban construction land expansion in Zhangye City is quantitatively analyzed and evaluated.The results show that,(1)from 1985 to 2020,the scale of construction land in Zhangye City expanded rapidly,which can be divided into the following stages:slow expansion from 1985 to 1995;medium speed expansion from1995 to 2000;rapid expansion from 2000 to 2005;after 2005,it expanded rapidly.(2)The expansion of urban construction land has strong directionality.The main direction of expansion takes 2010 as the node,first concentrated in the northeast and then transferred to the west of the city.(3)The spatial form of urban construction land has changed from irregular and unstable“strip”to simple and stable“block”.(4)The coordination between the expansion of urban construction land and population growth and economic development in Zhangye City is poor,and the expansion of urban construction land is obviously too fast.