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1.
中国城市空间拓展研究动态   总被引:3,自引:1,他引:2  
本文在总结了近年来中国城市空间拓展在形态与模式、空间拓展机制、空间拓展动态模拟、空间拓展环境效应等多方面所取得的丰硕成果和研究进展的基础上,提出现阶段中国城市空间拓展研究的主要特点是采用定量化的研究方法,筛选城市空间拓展的驱动因素,应用遥感和地理信息系统获得城市空间拓展准确信息,在此基础上构建模型对不同时空尺度的城市空间拓展过程加以模拟,并对城市空间拓展引起的生态环境效应加以分析,以此开展相关理论研究工作。针对目前研究工作特点和存在的不足,本文认为,今后中国城市空间拓展的主要发展方向应是借助日臻完善的研究手段和方法,深入开展城市空间拓展合理性评价,构建定量化动态模型,协调城市空间用地的增量布局与存量调整,并加强与国外城市空间拓展的比较研究。  相似文献   

2.
系统开展城市扩张研究,是防治城市蔓延、促进城市精明增长的重要基础。利用文献研究法总结国内外城市扩张内涵与度量的研究进展,并对发展趋势进行评述。研究表明:城市扩张度量研究备受关注,成果产出呈逐年增长之势。从代表性论文发表情况来看,“刊源集中”、“稿源集中”特征明显,中、美两国城市扩张研究成果产出量大,国内学者仍需在提升成果影响力上持续发力。城市扩张内涵界定百家争鸣,但国内外学者已形成一定的共识,即城市扩张是对特定城市发展模式下城市形态的“现实性”描述。尽管已形成了“城市用地扩张”和“城市蔓延”两大代表性研究框架,城市扩张概念内涵仍需进一步完善。城市扩张度量研究成果丰硕,但已有指标和模型多从单一的“时间”或“空间”维度表征城市扩张时序演化规律或空间格局,新数据、新理论及新方法应用有望促进城市扩张度量“时空统计模型”研究。城市扩张度量实证涉及全球、国家、流域、城市群、城市、街道等多个尺度,中国成为城市扩张度量研究的热点区域。研究呼吁重视在充分顾及区域制度与社会经济状况及城市管理需求差异前提下的城市扩张内涵界定,强化城市扩张度量时空统计模型研究,积极推进微观尺度城市扩张度量及成果应用。  相似文献   

3.
Urban expansion models are useful tools to understand urbanization process and have been given much attention. However, urban expansion is a complicated socio-economic phenomenon that is affected by complex and volatile factors involving in great uncertainties. Therefore, the accurate simulation of the urban expansion process remains challenging. In this paper, we make an attempt to solve such uncertainty through a reversal process and view urban expansion as a process wherein the urban landscape overcomes resistance from other landscapes. We developed an innovative approach derived from the minimum cumulative resistance (MCR) model that involved the introduction of a relative resistance factor for different source levels and the consideration of rigid constraints on urban expansion caused by ecological barriers. Using this approach, the urban expansion ecological resistance (UEER) model was created to describe ecological resistance surfaces suitable for simulating urban expansion and used to simulate urban expansion in Guangzhou. The study results demonstrate that the ecological resistance surface generated by the UEER model comprehensively reflects ecological resistance to urban expansion and indicates the spatial trends in urban expansion. The simulation results from the UEER-based model were more realistic and more accurately reflected ecological protection requirements than the conventional MCR-based model. These findings can enhance urban expansion simulation methods.  相似文献   

4.
The urban expansion process in China from the 1970 s to 2013 was retrieved based on remote sensing and GIS technology. With the latest zoning method used as reference, annual expansion area per city, urban expansion type, and fractal dimension index were employed to analyze the Chinese urban expansion characteristics and its spatial difference from the aspects of urban expansion process, influence of urban expansion on land use, and urban spatial morphological evolutions. Results indicate that 1) under the powerful guidance of policies, urban expansion in China went through six different stages, and cities in the eastern region entered the rapid expansion period the earliest, followed by cities in the central, northeastern and western regions; 2) cultivated lands and rural settlements and industrial traffic lands were the important land sources for urban expansion in China; the influence of urban expansion on land use in the eastern region was the strongest, followed by the central, northeastern and western regions; 3) urban spatial morphology tended to be complex and was directly related to the adopted spatial expansion mode. Infilling expansion became the main urban expansion mode in the western region first, then in the central and northeastern regions, and finally in the eastern region. This study establishes the foundation for an in-depth recognition of urban expansion in China and optimization of future urban planning.  相似文献   

5.
中国城市群城市用地扩张时空动态特征   总被引:7,自引:1,他引:7  
欧阳晓  朱翔 《地理学报》2020,75(3):571-588
认识城市群城市用地扩张特征、扩张质量及景观生态效应等综合信息将有助于城市群空间高质量发展规划与决策。选取10个不同发育等级的城市群作为研究对象,综合运用城市用地扩张强度指数、城市用地扩张强度差异指数、景观扩张指数、景观格局指数,分析1990—2015年期间城市群城市用地扩张时空特征及景观生态效应,并构建人口、经济与城市用地协同发展指数,据此分析城市用地扩张中“人—地”关系协同程度。结果表明:① 1990—2015年,各个城市群城市用地面积持续增加,建成区的范围不断扩大,扩张强度呈现“上升—下降”的趋势;在2010年之前成熟型城市群的扩张强度最高,2010年之后培育型城市群成为扩张强度最高的类型。② 城市群城市用地扩张总体上呈现不均衡布局的趋势,高速扩张区域主要分布在沿海地区。从全国视角来看,东部高于中、西、东北部,整体城市群快速扩张的中心由东向西移动。③ 城市群城市用地空间扩张模式表现出边缘式和飞地式两种空间扩张模式并存,不同发育等级之间具有明显差异性,成熟型城市群的空间结构较为稳定,其他两种类型的城市群空间结构初具雏形或尚未形成。④ 城市群城市用地扩张“吞没”了郊区和农村地区,破碎化程度、形状的复杂程度较高,景观格局表现出不稳定。⑤ 城市群“人口—土地”协同程度逐步增强,“经济—土地”协同程度整体较高,整体上表现出城市用地扩张质量有所提升。新时期城市群城市用地应严格控制扩张规模,加快中小城市的发展,促进城市群城市用地扩张均衡发展,为城市群国土空间高质量发展提供重要参考。  相似文献   

6.
Influence of urban expansion on the urban heat island effect in Shanghai   总被引:1,自引:0,他引:1  
The urban heat island (UHI) effect resulting from rapid urbanization is attracting increasing attention among the global scientific community. This research analyzed the relationship between urban expansion and the UHI effect utilizing an integrated approach, including urban land interpretation and retrieving land surface temperature based on remote sensing, and spatial overlay analysis for revealing the relationship for different time periods between 1984 and 2014 in Shanghai, China. The results show that (1) the spatiotemporal changes in UHI are consistent with the expansion of urban land, and rapid urban expansion leads to an expansion of the UHI, in particular along roadways. (2) The mode of urban expansion is an important factor influencing the UHI effect. Urban sprawl (urban expansion in the edge-expansion way) is a form of typical expansion that leads to the rapid increase in the UHI. When the urban compactness ratio is less than 0.15, a compact design can effectively control the expansion rate of the UHI and mitigate its range of influence and intensity. However, when the urban compactness ratio is greater than 0.15, the urban design has a marked influence on the UHI ratio index: a more compact form produces a stronger UHI effect. So, finding an equilibrium between urban compactness ratio and urban expansion rate is good for effective urban management and planning.  相似文献   

7.
一种新的城市景观扩张过程测度方法:多阶邻接度指数   总被引:2,自引:2,他引:0  
刘稼丰  焦利民  董婷  许刚  张博恩  杨璐迪 《地理科学》2018,38(11):1741-1749
提出多阶邻接度指数(Multi-order Adjacency Index, MAI),应用多阶缓冲区完善对新旧斑块间空间关系的识别,从而更为详细地揭示城市扩张过程特征。MAI的延伸公式可供自下而上从宏观分析城市整体的扩张程度及空间变化过程。选取武汉市作为研究区,基于4期遥感影像(1995、2000、2005和2010年)划分3个时段应用MAI分析武汉市城市景观格局的演变特征。结果表明,MAI能够详细地反映出新增城市斑块在空间上有更加离散的分布趋势,新增斑块的扩张程度逐渐加深,建成区的边界不断向外延展。比较MAI与LEI(Landscape Expansion Index, LEI)的特征差异,指出MAI能够更加详尽地反映新旧斑块间的空间位置关系。  相似文献   

8.
The urban expansion process in China from the 1970s to 2013 was retrieved based on remote sensing and GIS technology. With the latest zoning method used as reference, annual expansion area per city, urban expansion type, and fractal dimension index were employed to analyze the Chinese urban expansion characteristics and its spatial difference from the aspects of urban expansion process, influence of urban expansion on land use, and urban spatial morphological evolutions. Results indicate that 1) under the powerful guidance of policies, urban expansion in China went through six different stages, and cities in the eastern region entered the rapid expansion period the earliest, followed by cities in the central, northeastern and western regions; 2) cultivated lands and rural settlements and industrial traffic lands were the important land sources for urban expansion in China; the influence of urban expansion on land use in the eastern region was the strongest, followed by the central, northeastern and western regions; 3) urban spatial morphology tended to be complex and was directly related to the adopted spatial expansion mode. Infilling expansion became the main urban expansion mode in the western region first, then in the central and northeastern regions, and finally in the eastern region. This study establishes the foundation for an in-depth recognition of urban expansion in China and optimization of future urban planning.  相似文献   

9.
冯浩城  杨青山 《地理科学》2017,37(8):1178-1185
在RS和GIS的支持下集成多源数据,重建了建三江垦区下辖农场1990年、2000年、2010年和2015年4个时期的城镇用地格局。应用动态度模型等探讨了建三江垦区城镇用地扩张的时空特征及区域差异,分析了其驱动因素。结果表明:1990~2015年,建三江垦区城镇用地面积增加了3 237.5 hm2,平均扩张速率为130 hm2/a,扩张速率最显著的阶段是2000~2010年。 垦区下辖农场城镇用地扩张时空差异明显,建三江管局所在城镇扩张面积最大;浓江农场扩张相对比例最大;动态度模型分析发现二道河农场扩张速度最快,勤得利农场的城镇用地扩张速率最慢,扩张面积最小。 建三江垦区以农场为城镇单元的建设用地扩张模式主要为线性轴状扩张。城镇人口数量、经济水平的不断提升、产业结构的优化与区域政策极大地促进了垦区城镇用地的扩张,交通条件是城镇扩张速率和模式的重要影响因素。  相似文献   

10.
Spatial patterns of urban expansion mainly include infilling, edge expansion, and outlying growth patterns. The cellular automata (CA) model, is an important spatio-temporal dynamic model and effectively simulates infilling and edge-expansion urban expansion. but is evidently lacking in outlying scenarios. In addition, CA cannot explain the causes and processes of urban land expansion. Given these limitations, we proposed a novel urban expansion model called simulation model of different urban growth pattern (SMDUGP), which can work well in both adjacent (i.e., infilling and edge expansion) and outlying growth patterns. SMDUGP has two main components. First, we divided the non-urban region into two categories, namely, candidate region for adjacent pattern urban growth (CRFAP) and candidate region for outlying pattern urban growth (CRFOP). Second, different methods were utilized to simulate urban expansion in the different categories. In CRFAP, a CA model based on the potential of urban growth was proposed to simulate urban growth in relatively randomly selected urban growth regions based on the discrete selection model and Monte Carlo method as the expansion area was implemented in CRFOP. Huangpi, a suburban area in Wuhan, is utilized as the case study area to simulate the spatial and temporal dynamics of urban growth from 2004 to 2024. SMDUGP can effectively simulate outlying urban growth with a highly improved simulation precision compared with the traditional CA model and can explain the causes and processes of urban land expansion.  相似文献   

11.
快速城市化阶段济南城市空间扩展及驱动力研究   总被引:2,自引:0,他引:2  
王成新  窦旺胜  程钰  刘凯 《地理科学》2020,40(9):1513-1521
基于济南市1992年、2000年、2010年、2018年Landsat遥感影像数据,借助ArcGIS、ENVI等图像分析工具,提取济南城市建成区,从扩展速度、强度、分形维数、紧凑度、重心转移等方面探究济南城市空间扩展的时空变化过程、特征,运用地理加权逻辑回归方法对济南城市空间扩展驱动力进行分析。结果表明:① 济南城市空间扩展经历“中强低速”“高强中速”“低强高速”3个阶段,城市形态趋于稳定,城市形状呈现东西向条带状分布格局,紧凑度较差;② 1992—2018年济南城市空间向E、NEE、NE方向扩展最为显著,扩展方式以外延扩张与内部填充为主,城市空间分布重心东移态势明显;③ 济南城市空间扩展受多重驱动因子影响,主驱动因子为距城市建成区距离、距主要公路距离、地区生产总值、城镇化率、人口密度等。  相似文献   

12.
印度是人口仅次于中国的发展中国家,也是“一带一路”倡议的重要节点。印度正处于城市化快速发展阶段,分析印度城市化特征具有重要意义,而中国国内关于印度城市化和城市扩张的研究和报道相对较少。论文选取10个人口超过100万的印度城市,获取1990、2000和2014年基于Landsat影像的土地利用数据和人口数据,采用圈层分析法将城市划分为等间距的同心圆圈层后统计各圈层内建设用地密度,选取增长率、密度、强度以及景观指数指标对印度城市扩张进行多维度对比分析。研究发现:①城市土地扩张快于人口增长,1990—2000、2000—2014年土地年均增长率分别是人口年均增长率的3.27和2.43倍。②建设用地密度随着与城市中心距离增加而衰减,且在一定距离内快速下降;同圈层内建设用地密度随时间逐渐增加;城市以分散的方式向外扩张,城市形态变得更加松散,特别是在第二阶段(2000—2014年)。③建设用地斑块破碎化程度与城市扩张强度的空间变化相吻合。城市扩张最活跃区域与景观破碎度最严重区域都随时间不断向外推进,城市扩张对景观格局产生显著影响。在全球城市扩张背景下,研究结果将为理解城市扩张时空特征而提供印度样本,也将为研究其他地区城市扩张提供分析方法和思路。  相似文献   

13.
基于凸壳原理的杭州城市扩展形态演化分析   总被引:6,自引:1,他引:5  
在城市化快速推进的背景下,探索凸壳原理在城市扩展形态识别中的应用价值,并借此分析杭州市主城区1985~2010年间城市扩展形态演化规律及其机理,以期为控制城市扩展形态,指导未来城市土地开发活动提供借鉴。研究发现,凸壳原理在城市扩展形态识别上简单而明确,通过确定已有城市建设用地的凸壳,将城市所有可开发用地明确区分为凸壳内用地和凸壳外用地2类,为采取差别化的空间管理政策提供依据。构建了基于凸壳原理的城市扩展形态计算机识别方法,有利于在城市扩展模拟中实现城市扩展形态影响因素的定量化表达。1996年之前,杭州市建设用地和凸壳面积增长缓慢,城市形态相对紧凑;1996年之后,建设用地快速增长,城市不均衡扩展加剧,凸壳面积陡增,城市形态紧凑程度下降。总体来看杭州市城市扩展类型属于外延型,随着凸壳面积的增加,城市填充潜力随之增强,为促进杭州市城市紧凑化发展,应该严格控制凸壳外的城市土地开发。沿主干道的城市开发是城市形态外延式发展的主要因素,已有建设用地周边以及城市内部次要道路沿线的城市开发,以及城市中心的集聚作用和规划对城市开发的控制是城市形态填充式发展的主要因素,而郊区化发展和“东扩西进”等城市空间发展政策促使特定时期城市外延式发展。  相似文献   

14.
China has experienced and is experiencing expeditious urban expansion in the recent decades, especially in the coastal areas and big cities. Rapid urban expansion and dramatic changes of landscape have caused great economic, environmental and social impacts consequently. It is crucial to understand urban temporal, spatial expansion patterns and their related effects. In this paper, urban expansion of Guangzhou, a rapid growing city in south‐east China, from 1979 to 2003 is studied temporally and spatially. Four time ranges including 1979–1990, 1990–1995, 1995–2000 and 2000–2003 are designed and the urban expansion area, expansion rate and the spatial expansion pattern are discussed by using remote sensing data and Geographical Information System (GIS) tool. Two transects are designed along two axes of Guangzhou expansion and the structural of urban expansion patches at different orientations are compared in order to quantitively understand the urban expansion of Guangzhou during the past 24 years. The gradient analysis integrating multi‐temporal data is performed in order to analyze and compare the spatial and temporal dynamics of urban expansion. Two indices of compactness and fractal dimensional index are used to describe the urban developing pattern in the study time durations. And the influence of different types of traffic roads to urban expansion is evaluated using the buffer analysis of GIS. The results show that: (1) temporally, urban area of Guangzhou increase 296.54 km2 from 141.15 km2 in 1979 to 437.70 km2 in 2003 and the increasing rate is up to 210.08%; (2) spatially, Guangzhou has different urban expanding directions in different stages and the general expanding directions are towards northeast, north, southeast and north in four studied time ranges; (3) transportation lines play a very important role in urban expansion of Guangzhou, but different types of road have different impacts. National roads and highways exhibit stronger control to urban expansion than provincial roads; and (4) expansion of Guangzhou has gradually changed from a compact pattern to leapfrogging and disordering patterns.  相似文献   

15.
基于服务空间视角的长春市城市功能空间扩展研究   总被引:4,自引:3,他引:1  
中国快速城镇化背景下城市功能空间迅速扩展引起了广泛关注。以长春市用地现状图和统计资料为数据源,借助ArcGIS和SPSS软件平台,引用多种模型基于服务空间视角研究了1995年以来长春市城市功能空间扩展的特征、效应与驱动机制。研究发现:1995~2013年长春市城市空间扩展迅速,扩展模式整体上以圈层式近域扩张为主,城市与服务空间整体的偏离问题始终存在,城市开发建设过程中服务空间明显滞后于城市空间的扩张。城市空间快速扩展产生了城市蔓延、功能空间失衡和城市功能空间的优化升级等效应。行政因素和社会经济因素是城市空间扩展的主要驱动因素,回归模型结果表明人口城市化和人居环境水平的提高是城市功能空间本质内涵扩展的社会经济核心因素。  相似文献   

16.
扩张强度指数(Expand Intensity Index, EII)是目前城市扩展数量特征研究的常用指标,用以表征城市扩张程度和速度,但该指标是从城市扩张的结果,即从城市用地面积变化角度对物质空间变化的简单描述与分析,忽略了人在空间中的感受,未能从城市扩张的动因角度揭示城市扩张特征,缺乏对城市外部空间形态演变模式的深入研究,不能反映人在城市扩展空间上的活动。本文从交通网络对城市扩张的驱动作用入手,基于空间句法,提出一种新的扩张强度指数——基于空间句法的扩张强度指数(Space Syntax Expand Intensity Index, SS-EII),SS-EII包涵可反映空间集聚和离散程度的句法变量,可用于分析空间可达性的变化等情况。与传统扩张强度指数相比,SS-EII是基于空间句法从城市扩张的驱动力方面计算扩张强度,不仅关注城市扩张的结果,同时关注交通对城市扩张模式、方向的导向作用和人主观感知下城市空间的变化。将SS-EII应用于广东省棉湖镇2002-2014年期间的城镇扩展特征分析中,研究结果表明,SS-EII可用于分析比较建成区不同方向的扩张速率与建设状况,其计算结果与棉湖镇建成区实际扩张情况相符,与EII相关度R2达0.95以上。  相似文献   

17.
国内外城市空间扩展研究评析   总被引:10,自引:2,他引:8  
闫梅  黄金川 《地理科学进展》2013,32(7):1039-1050
城市空间扩展是城市化过程的重要标志, 而城市土地利用变化又是城市空间扩展最为直接的表现形式。随着全球城市化的推进, 城市空间扩展已成为国内外城市发展研究中的热点领域。国外城市空间扩展研究发端于20 世纪60 年代的计量地理革命, 中国城市空间扩展的研究自80 年代中期开始;2000 年以来, 伴随中国城市化的快速发展, 城市空间扩展问题日益突出, 城市空间扩展研究逐渐成为热点, 有关研究成果更是大量涌现。本文根据国内外城市空间扩展研究内容的变化, 运用文献资料法和对比分析法, 从扩展形态、扩展模式、动力机制、模拟预测、效应与调控5 个方面对城市空间扩展研究进行了系统总结与梳理。在国外与国内比较研究与综合分类基础上, 重点评析现阶段国内相关研究的特点和不足, 并对中国未来城市空间扩展的研究趋势进行了展望。  相似文献   

18.
城市扩展模拟可为城市可持续发展与国土空间规划提供参考。智能体模型(ABM)与元胞自动机(CA)结合可兼顾城市空间增长的自组织性和不同决策主体的决策过程,人工神经网络(ANN)可描述智能体与城市扩展之间复杂的非线性关系。该文基于ANN-ABM-CA耦合模型,在构建CA转换规则时基于ABM刻画人类决策行为的影响,并采用ANN挖掘不同类型的智能体在城市扩展过程中的偏好差异,同时考虑宏观和微观层面的智能体决策行为,结合城市扩展的10个驱动因素,模拟武汉市主城区2005-2015年的扩展情况,结果表明:1)相比传统的ANN-CA模型,ANN-ABM-CA模型模拟性能更优,从宏观与微观相结合的角度更好地解释了城市扩展的驱动机制,OA值为97.46%,Kappa系数为0.9176,FoM值为0.4375,结果可靠且合理;2)不同收入层级的居民智能体对城市扩展的决策偏好不同;3)武汉主城区城市扩展模式主要为边缘型扩展,洪山区西南部有少部分填充型扩展、东南部出现飞地型扩展,与实际扩展情况相符。  相似文献   

19.
苗毅  苏晓波  宋金平  花晓波 《地理研究》2021,40(6):1716-1731
围绕边境城市瑞丽的两处口岸,结合1989—2019年Landsat和夜间灯光数据,以空间分析与多元空间Logistic回归,探讨边境口岸区城市扩张的过程与特征。研究发现:① 瑞丽、畹町口岸区城市均有扩张但差异显著,空间上分别具有指向口岸、沿边境线迁移的重心轨迹,以及岸城融合相向发育、飞地扩张的热点演变特征;② 回归分析发现,瑞丽口岸贸易在2004—2009年对邻近该口岸地区的城市扩张具有显著的促进作用,此后伴随姐告边贸区部分功能外移,又促成城市扩张在空间上呈逐渐远离口岸点的特征,对瑞丽口岸区城市扩张影响显著,而畹町口岸贸易并未有效促成畹町口岸区城市扩张,且后者还易受到其他口岸、通道包括自然因素的影响;③ 多因素及空间竞合关系下,瑞丽、畹町口岸区城市扩张以1999年和2009年为界呈差异化的三阶段特征,两口岸区城市用地也均围绕边境、口岸发育延展,具有明确方向性和空间特殊性。最后,研究区未来发展仍面临不确定因素,不同口岸发展要注重实际及边境促进或限制城市扩张的双重属性,结合口岸贸易结构等的更丰富的案例有待探讨,以更全面地解释边境城市扩张机制。  相似文献   

20.
Delimitation of an urban growth boundary (UGB) can effectively curb disorderly urban expansion, optimize urban development space and protect the ecological environment. Eco-environmental sensitivity was evaluated and areas prohibiting construction expansion were extracted by establishing an index system. Point of interest (POI) and microblog data were utilized to analyze the expansion of residential activity space. Urban space expansion potential was calculated using a comprehensive evaluation model, and an urban growth boundary for Jinan in 2020 was delimited combining the predicted urban expansion scale. The results showed that: (1) An evaluation of eco-environmental sensitivity can effectively protect ecological land and provide an ecological basis for urban expansion. Regions with high eco-environmental sensitivities in Jinan are located along the banks of the Yellow River and Xiaoqing River and in southeast mountainous areas, but eco-environmental sensitivities in the central, north and southeast areas are relatively low; (2) The model to evaluate urban residential activity expansion can quantify the spatial distribution of urban residents' activities. Regions with high potential for residential activity space expansion in Jinan are mainly concentrated in the middle of Jinan and most are part of existing built-up areas and surrounding areas; (3) The method that delimits urban growth boundaries based on the coordination of ecology and residential activity space is reasonable. Spatial expansion in Jinan mainly extends towards the east and west wings, and the boundary conforms to the spatial strategy guiding Jinan’s development and is consistent with the overall layout in related plans. Considering both ecological protection and the internal forces driving urban expansion, the method of urban growth boundary delimitation used in this study can provide a reference and practical help for studies and management of urban development in the new era.  相似文献   

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