摘要
成渝地区双城经济圈是我国城市群发展的第四极,对其城市扩张时空演变特征的分析能为区域规划和决策提供参考。文章选取了成渝地区45个城市为研究对象,通过GEE提取了1990—2019年的城市用地,采用圈层梯度分析法和城市用地密度函数,对比分析不同规模城市的扩张特征。结果表明:(1)研究区城市扩张具有明显的空间差异,成都、重庆双核的扩张速度较快,带动了沿线及周边城市的发展,但总体上中小城市发展相对滞后,城镇体系结构及区域协同性有待加强。(2)从城市紧凑度(K_(p))、扩张速度(D)来看,城市半径随时间而扩大,多数大中城市的紧凑度下降,而小城市趋于紧凑。(3)根据城市形成演变特征,可划分为高速发展型、集聚增长型、分散发展型、发展滞后型4类,其中特大城市和大城市为高速发展型,区域性中心城市为集聚增长型,成渝连接区域的中等城市为分散发展型,小城市为发展滞后型。
Chengdu-Chongqing Twin-City Economic Circle is the fourth-largest urban agglomeration in China,whose spatial and temporal urban expansion characteristics offer references for regional planning and decision making.We extract the urban expansion dynamics(1990-2019)of 45 administrative divisions from the Chengdu-Chongqing area using Google Earth Engine(GEE),compare and analyze the expansion characteristics of these cities based on circular-gradient analysis and inversed S-function.The results show that:(1)The urban expansions pose significant spatial differences:Chengdu and Chongqing,the two core urban areas,have the fastest urbanization process and drive the urban development of nearby cities,the small and medium-sized cities have a relatively slow expansion process,and their urban system structure and regional synergy need to be strengthened.(2)The urban compactness(K_(p))and expansion speed(D)reveal that all urban radiuses expanded over time,the compactness decreased in most large and medium-sized cities but increased in some small cities.(3)The urban formation and evolution of the cities can be divided into four types:megacities and large cities are of the high-speed development type,regional central cities are of the agglomeration growth type,medium-sized cities in the Chengdu-Chongqing connection region are of the decentralized development type,and small cities are of the development lag type..
作者
李春
王金柱
刘勇
刘秀华
LI Chun;WANG Jinzhu;LIU Yong;LIU Xiuhua
出处
《现代城市研究》
北大核心
2023年第11期34-41,50,共9页
Modern Urban Research
基金
西部平原城市与山地城市多中心开发的环境绩效比较研究(41771534)
土地财政转型视角下城市蔓延响应特征及治理策略研究(71974022)。