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1.
中国特大城市空间形态变化的时空特征   总被引:64,自引:4,他引:60  
基于国家资源环境数据库动态土地利用数据, 借助GIS软件支持, 分别计算了1990年和2000年中国31个特大城市平面轮廓形状的分维、紧凑度和形状指数以及城市的用地扩展类型。结果表明, 从1990年到2000年, 中国31个特大城市空间形态的总体变化趋势是, 城市用地空间扩展类型以填充类型为主, 外延类型相对较少且主要发生在发展限制较小的平原地区。总体上, 分维呈减少趋势且南方城市大于北方城市, 形状指数有减少, 城市空间形状有紧凑化趋势。综观1990年和2000年中国31个城市的分维、紧凑度和形状指数的数据, 可以看出广州、南昌、济南、成都、北京和上海等城市形状变化比较大, 而兰州、太原和唐山等城市形状变化很小。若用地扩展为填充类型, 则分维减少, 紧凑性增加, 形状指数减少;相反, 若用地扩展为外延类型, 分维增加, 紧凑性降低, 形状指数增加。  相似文献   

2.
中国特大城市空间形态演变研究   总被引:1,自引:0,他引:1  
以2008年全国52个百万人口以上的特大城市为样本,分析了1990-2008年中国特大城市空间形态在形状指数、空间紧凑度和空间破碎度方面的演变特征。研究表明:1)中国特大城市空间形态趋向带状特征,形状率和圆形率指数均呈下降趋势,下降幅度最大的是西北部、西部和东部地区的城市;2)空间紧凑度下降,面积-周长紧凑度和面积-轴线紧凑度指数均呈下降趋势,下降幅度最大的是西部地区的城市;3)空间破碎度趋于增强,分形维数呈上升趋势,上升幅度最大的是西南和东南部地区的城市;4)影响中国特大城市空间形态特征变化的因素主要有城市规模的扩大、新型城市空间要素的出现和城市空间结构的多中心化。  相似文献   

3.
特大城市空间形态差异对交通网络效率的影响   总被引:3,自引:1,他引:3  
以交通网络出行迂回作为交通网络效率分析的切入点,选取形状指数、紧凑度作为空间形态分析指标,对特大城市空间形态布局进行类型划分,并挖掘各城市交通网络效率空间分布差异特征,基于多元回归模型剖析中国各特大城市空间形态布局与交通网络效率之间的影响关系。研究表明: 5种类型城市交通效率高低分布差异明显,紧凑圆形城市边缘区交通网络效率较低,而非紧凑带形交通效率低的区域多分布于城市核心区,紧凑方形城市交通网络效率高地区分布较为集中,而非紧凑方形交通效率低的地区分布较为分散,紧凑带形城市面积越小则交通效率越高。就城市空间布局与交通网络效率影响关系而言,随着城市形状指数的增大,城市交通迂回值未进一步增大,说明城市形态布局接近圆形均匀分布时,其城市交通网络效率较高;随着城市紧凑度值的增加,城市交通迂回程度值亦不断增加,说明城市形态布局程度越紧密,反而其交通网络效率越低,当城市形态布局紧密程度适中时,交通网络效率水平较高。  相似文献   

4.
紧凑型城市发展是相对于分散型城市发展较为经济的一种发展模式。为探索东北三省城市紧凑度现状及特征,首先,从土地利用紧凑性、经济紧凑性、人口紧凑性、基础设施紧凑性,环境协调等方面切入,建立紧凑度评价的指标体系,运用熵值法对东北三省地级及以上城市的紧凑度进行了评价,并从空间和数量统计角度,应用SPSS软件,归类分析了城市紧凑度的分布特征;其次,以计算得到的紧凑度指数为基础,借助GIS软件,运用空间全局/局部自相关分析方法对东北三省城市紧凑度分布的相关性进行了分析,并利用地理加权分析方法,对紧凑度与影响紧凑度分布的主要因子的关联性进行分析。研究结果表明,东北三省城市紧凑度呈现出较为突出的极化分布现象,不同主因子对紧凑度分布影响的差异性显著。  相似文献   

5.
低碳视角下城市空间形态紧凑度研究   总被引:7,自引:1,他引:6  
吕斌  孙婷 《地理研究》2013,32(6):1057-1067
全球气候变化背景下,构建功能紧凑的低碳城市空间形态已成为世界各地城市实现低碳化可持续发展的主要途径之一。但目前的城市形态研究主要集中在城市外部空间,缺乏对城市内部功能空间紧凑度的量化。从实现低碳城市的视角,提出了城市内部功能空间形态紧凑度的量化指标,用以探讨实现低碳城市的城市空间形态特征;以商业、医疗、教育和文化娱乐等4种重要服务设施布局为基础,构建了城市功能空间紧凑度指数,对不同规模、不同地理条件类型的8个案例城市进行定量研究,实证了城市内部“功能空间紧凑度”指标较城市外部“形态紧凑度”指标能够更好的反映城市形态的紧凑性内涵,适用于评价各类城市空间形态的低碳发展模式。  相似文献   

6.
以工业园区形式为主的工业用地扩展对城市空间演变产生着深刻影响。利用长沙市1949—2013年的城市用地资料,通过计算城市与工业的用地扩展强度指数、等距扩散缓冲强度峰值、重心轨迹、形状紧凑度与空间效率等城市空间衡量指标,分析工业用地扩展的时间特征,揭示工业用地扩展引导城市空间发展由内向填充走向外向扩展、空间模式由单中心走向多中心、空间结构由圈层走向轴向、空间联系由松散走向紧凑等规律,并从总体规划层面提出相应的城市空间优化策略,引导工业用地的合理规划。  相似文献   

7.
基于空间紧凑发展内涵,构建综合指数模型,分析2005—2020年上海空间紧凑度的演变特征并与国内外城市进行比较,进一步利用时空地理加权回归模型分析城市形态结构对空间紧凑度的影响效应。研究发现:(1)空间紧凑度呈现中心高外围低的圈层式分布特征,中心城区普遍趋于稳定,外围城区增长较快,且与其他同类城市比较处于高紧凑发展水平;但受政策及规划影响,紧凑度分指标在空间格局上存在显著差异。(2)城市密度与空间紧凑度呈倒“U”型关系,功能混合度和用地形态与空间紧凑度呈近线性关系,且城市密度与之关联性最强。(3)整体上城市密度和功能混合度均对空间紧凑发展产生促进效应,而用地形态表现出抑制效应;分区尺度上形态、功能和密度要素对空间紧凑度的影响效应存在显著差异。(4)通过中心城区与外围城区的差异性空间结构调整,控制国土空间规划形态结构指标来提升城市紧凑发展水平。  相似文献   

8.
中国城市群紧凑度的综合测度分析   总被引:27,自引:3,他引:24  
方创琳  祁巍锋  宋吉涛 《地理学报》2008,63(10):1011-1021
城市群紧凑度是指在城市群形成与发育过程中; 所体现出的城市(城镇)、产业、资源、 资金、交通、技术、人才等物质实体按照一定的经济技术联系在空间上的集中程度; 包括城 市群产业紧凑度、城市群空间紧凑度和城市群交通紧凑度等类型。适度的紧凑度是城市群综 合效益最大化的集中体现; 城市群紧凑度过高、过低都不利于城市群的健康发展。从产业、 空间和交通三大视角入手; 通过构建城市群紧凑度的综合测度模型; 对选取的23 个城市群紧 凑程度进行分析后认为; 中国城市群紧凑度总体不高; 且空间差异性大; 根据这种差异; 采用聚类分析法可将中国城市群综合紧凑度划分为高度紧凑、紧凑、中度紧凑、低度紧凑和不紧凑(分散) 5 个等级。城市群综合紧凑度呈现出由东向西、由南向北逐渐降低的分异态势。 城市群综合紧凑度与城市群发育程度呈现出高度的正相关性。如何科学调控城市群紧凑程度; 紧凑程度达到一种什么样的标准才是最佳选择; 这是本文研究中试图回答的问题。该研究为 我国城市群的形成与发育; 为建设资源节约型城市群、环境友好型城市群、生态型城市群和 高效型城市群提供定量的决策依据; 为推动我国城市群的适度集聚和健康发展奠定科学基础。  相似文献   

9.
GIS空间分析技术为空间形态的精准判别提供了新的路径和研究视角。本文通过高分辨率Google Earth影像提取2013年珠江三角洲城市群的工业生产空间分布信息,运用分形模型、形态紧凑度、空间离散度、密度指数定量分析珠三角工业生产空间的形态特征,采用GIS空间分析并结合社会经济统计分析进一步探讨了影响其分布的主要因素。结果表明:①2013年珠江三角洲城市群的工业生产空间共有2604.71 km2,其空间分布呈现典型的“核心—边缘”结构,并且形成了交错式、零散式和集中式3种分布模式。②珠江三角洲城市群的工业生产空间具有很强的分形特征,核心区的分形维数整体小于外围地区,而空间结构的稳定性高于外围地区;珠三角各市中,工业生产空间形态紧凑度最高的为珠海、最低的为广州,而空间离散度最高的为惠州、最低的为中山;珠三角各市工业生产空间的规模差异显著,与经济规模、人口规模、工业企业数等呈较强的正相关关系,而东莞、深圳、中山、佛山的密度指数过高,需加强工业生产空间的集约高效利用。③自然因素与交通条件、城镇化与开发区的发展、政策的引导和调控以及经济全球化是珠江三角洲城市群工业生产空间分布的主要影响因素。  相似文献   

10.
长沙市土地利用格局变化的空间粒度效应   总被引:7,自引:1,他引:6  
基于2003年、2006年、2009年及2013年的遥感图像对长沙市土地利用进行分类,在ArcGIS 10.0、ENVI 4.8、Fragstats 4.0和Excel 2007软件的支持下,通过上推尺度像元的比例占优法改变空间粒度,从类型水平和景观水平上分析了土地利用格局变化的粒度效应。得出以下结论:类型水平上,随着粒度的增大,各土地类型的指数呈现出3种变化趋势:增大、减小及无明显规律;随着时间的变化,空间粒度越小,对斑块密度及斑块形状指数变化的影响越明显。空间粒度越大,对斑块结合度和斑块集聚度变化的影响越明显。景观水平上,随着粒度的增大,蔓延度指数先减小后基本不变;香农多样性指数和香农均匀度指数缓慢减小;随着时间的变化,蔓延度指数呈减小的趋势,香农多样性指数和均匀度指数呈增大的趋势。90 m是本研究中分析空间粒度的最佳值。  相似文献   

11.
Shape characterisation is important in many fields dealing with spatial data. For this purpose, numerous shape analysis and recognition methods with different degrees of complexity have so far been developed. Among them, relatively simple indices are widely used in spatial applications, but their performance has not been investigated sufficiently, particularly for building footprints (BFs). Therefore, this article focuses on BF shape characterisation with shape indices and classification schemes in a GIS environment. This study consists of four phases. In the first phase, the criteria for BF shape complexity were identified, and accordingly, benchmark data was constructed by human experts in three shape complexity categories. In the second phase, 18 shape indices were selected from the literature and automatically computed in GIS. The performance of these indices was then statistically assessed with histograms, correlation matrix and boxplots, and consequently four indices were found to be appropriate for further investigation. In the third phase, two new indices (Equivalent Rectangular index and Roughness index) were proposed with the objective to measure some BF shape characteristics more efficiently. The proposed indices also were found to be appropriate with the same statistical assessment procedures. In the final phase, BF shape complexity categories were created with the pairs of six appropriate indices and four choropleth mapping classification schemes (equal intervals, natural break, standard deviation, and custom) in GIS. The performance of the index–scheme pairs was assessed against the benchmark data. The findings demonstrated that both new indices and two of the selected indices (Convexity and Rectangularity) delivered higher performance. The custom classification scheme was found more ideal to reveal absolute shape complexity with the index value ranges derived from the boxplots while the other classification schemes were more appropriate to reveal relative shape complexity.  相似文献   

12.
20世纪40年代初以来中国大陆沿海主要海湾形态变化   总被引:11,自引:1,他引:10  
侯西勇  侯婉  毋亭 《地理学报》2016,71(1):118-129
受气候变化和人类活动的影响,中国海岸带正在经历各种剧烈的变化,海湾形态变化是其中的一个重要方面.基于地形图资料与遥感影像提取20世纪40年代初至2014年7个时相的中国大陆沿海主要海湾的空间信息,进而分析海湾岸线类型结构,开发利用程度和空间位置的变化特征,以及海湾面积,形状和重心分布的变化特征.结果表明,20世纪40年代初以来,中国大陆沿海主要海湾的形态变化显著且复杂,主要体现为:海湾岸线的结构变化显著,自然岸线的长度和比例急剧减少;海湾岸线的开发利用程度持续增强;海湾岸线普遍背陆向海运动;海湾面积普遍大幅萎缩;海湾形状总体趋向复杂但个体间的差异在缩小;海湾重心分布位置普遍背陆向海迁移;海湾变化具有显著的时空差异性等.总的来说,以围填海为主的人类活动是导致海湾发生上述变化特征的主要原因.通过研究,指出应该对中国的海湾进行功能定位划分和分类管理,通过强化以海湾为基本单元的管理,促进中国海岸带综合管理能力的提高和管理目标的实现.  相似文献   

13.
长沙城市土地扩张特征及影响因素   总被引:3,自引:2,他引:1  
This research systematically analyses land-use map of Changsha city in different periods of time. The spatial form and structural evolution was analysed by studying indices such as city land-use structure proportion, expansion intensity, economic flexibility, population flexibility, changing compactness index and so on. The dynamic mechanism of urban land expansion has been discussed by integrating the regional social economy development situation and many aspects such as the physiographical surrounding, population and economic development, traffic infrastructure, planning and regional development tactic and system innovation. The research indicates that the urban land expansion speed and intensity have steadily increased in Changsha from 1949 to 2004. The expansion form has been from a single external expansion to a combination form of external and internal expansion, from a circular or linear continuous form to a blocky or agglomeration shape. Overall, the urban land expansion of Changsha city is a phasic, diversified and complex process. And no matter what the stage is, it is an organic system containing multiple speed, pattern and shape, which are driven by multiple impetuses. The dominant feature at different stages was highlighted be- cause of the balance and fluctuation between different forces, and the existing urban land border and shape have resulted from the joint efforts of these phasic forces.  相似文献   

14.
This research systematically analyses land-use map of Changsha city in different periods of time. The spatial form and structural evolution was analysed by studying indices such as city land-use structure proportion, expansion intensity, economic flexibility, population flexibility, changing compactness index and so on. The dynamic mechanism of urban land expansion has been discussed by integrating the regional social economy development situation and many aspects such as the physiographical surrounding, population and eco-nomic development, traffic infrastructure, planning and regional development tactic and system innovation. The research indicates that the urban land expansion speed and intensity have steadily increased in Changsha from 1949 to 2004. The expansion form has been from a single external expansion to a combination form of external and internal expansion, from a circular or linear continuous form to a blocky or agglomeration shape. Overall, the urban land expansion of Changsha city is a phasic, diversified and complex process. And no matter what the stage is, it is an organic system containing multiple speed, pattern and shape, which are driven by multiple impetuses. The dominant feature at different stages was highlighted be-cause of the balance and fluctuation between different forces, and the existing urban land border and shape have resulted from the joint efforts of these phasic forces.  相似文献   

15.
The formation of an anisotropic landscape is influenced by natural and/or human processes, which can then be inferred on the basis of geometric indices. In this study, two minimal bounding rectangles in consideration of the principles of mechanics (i.e. minimal width bounding (MWB) box and moment bounding (MB) box) were introduced. Based on these boxes, four novel shape indices, namely MBLW (the length-to-width ratio of MB box), PAMBA (area ratio between patch and MB box), PPMBP (perimeter ratio between patch and MB box) and ODI (orientation difference index between MB and MWB boxes), were introduced to capture multiple aspects of landscape features including patch elongation, patch compactness, patch roughness and patch symmetry. Landscape pattern was, thus, quantified by considering both patch directionality and patch shape simultaneously, which is especially suitable for anisotropic landscape analysis. The effectiveness of the new indices were tested with real landscape data consisting of three kinds of saline soil patches (i.e. the elongated shaped slightly saline soil class, the circular or half-moon shaped moderately saline soil, and the large and complex severely saline soil patches). The resulting classification was found to be more accurate and robust than that based on traditional shape complexity indices.  相似文献   

16.
A measure of shape compactness is a numerical quantity representing the degree to which a shape is compact. Ways to provide an accurate measure have been given great attention due to its application in a broad range of GIS problems, such as detecting clustering patterns from remote-sensing images, understanding urban sprawl, and redrawing electoral districts to avoid gerrymandering. In this article, we propose an effective and efficient approach to computing shape compactness based on the moment of inertia (MI), a well-known concept in physics. The mathematical framework and the computer implementation for both raster and vector models are discussed in detail. In addition to computing compactness for a single shape, we propose a computational method that is capable of calculating the variations in compactness as a shape grows or shrinks, which is a typical application found in regionalization problems. We conducted a number of experiments that demonstrate the superiority of the MI over the popular isoperimetric quotient approach in terms of (1) computational efficiency; (2) tolerance of positional uncertainty and irregular boundaries; (3) ability to handle shapes with holes and multiple parts; and (4) applicability and efficacy in districting/zonation/regionalization problems.  相似文献   

17.
Strong correlations have been observed between potential indices and the densities of spatial variables. The conventional null hypothesis of bivariate regression is inappropriate for testing their significance. A randomization test is proposed and is applied to 1975 US population data by state. The resulting relationship has a significant correlation, but its slope could occur frequently under the null hypothesis. The correlation is shown to be related to the spatial autocorrelation of densities by constructing arrangements with prescribed values of the modified Moran index.  相似文献   

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