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1.
Globalization and informatization have accelerated city networking process over the world, which makes research on city network a hot topic in the fields of urban geography and economic geography. With Chinese economic structure adjustment and city economic growth, producer services have begun to play an increasingly important role in city-region networking. This paper employs the methodology of world city network to analyze and explain the spatial development characteristics of China’s urban network system based on the data of nationwide producer services enterprise network. The research result indicated that the distribution of producer services network has a positive effect on the development of Chinese city networks. City network connectivity is closely related to the significance of city in producer services development, and the former will gradually decline with the drop of the latter. Accordingly, the 64 cities can be divided into the national central cities, regional central cities, sub-regional central cities and local central cities in accordance with their position and role in the nationwide producer services network. It is concluded that high-grade cities with quality producer services dominate the pattern of Chinese city networks and there emerges three spatial agglomerations of producer services enterprises in Changjiang (Yangtze) River Delta, Zhujiang (Pearl) River Delta and Beijing-Tianjin-Tangshan Economical Region. Moreover, the distribution of different producer services industry varies from city to city, which also affects the characteristics of network development.  相似文献   

2.
深入研究高铁对珠江三角洲(简称珠三角)城市群区域经济空间格局的影响,对挖掘高铁与区域经济耦合关系具有一定的科学价值。本文基于2010、2014、2018年珠三角地区城市面板数据,从区域经济联系、区域优势潜力及区域经济空间平稳性3个维度,运用引力模型、区位优势潜力模型、Theil系数等技术模型和方法,综合测度高铁对珠三角城市群区域经济空间格局的影响。研究结果表明:① 珠三角城市间经济联系强度随年份的递增而呈现上升的趋势,南北向联系强于东西向联系,并逐渐出现1个经济联系核心区、3个经济联系副关联区和1个经济增长辐射区;② 珠三角市际间区位优势潜力差距逐渐拉大,其中东莞、中山等经济实力较强、城市地域规模、人口规模较小且地理位置优越的二三线城市在高铁运营过程中获得更大的利益;③ 从珠三角区域经济整体差异性来看,区域经济空间格局异质性呈先扩大后缩小趋势;从区内群体差异性来看,一二线城市之间经济发展水平差异呈先大幅上升后小幅下降趋势;二三线城市之间经济发展水平差异呈下降趋势。该研究将对未来交通规划提供参考。  相似文献   

3.
企业间的联系是城市联系的重要组成部分,加强对基于企业间联系的城市功能网络分析对丰富城市网络理论研究具有重要意义。采用2010—2020年上市公司与其前五大客户间的贸易关系数据构建了中国城市网络,基于企业间的贸易联系视角分析城市网络时空演变特征。研究表明:(1) 2010—2020年间城市网络规模呈现先升后降的特征,整体网络密度较低,位于0.014~0.018之间;网络重心呈现“S”形空间轨迹变化和整体向南移动的趋势,网络总体空间结构由沿海向“T”形结构转变;(2)网络流量集中于少数节点城市,资金进出量前20城市总额占资金总流量的71.9%,北京、上海是网络的绝对核心,杭州、武汉、深圳、广州等省会或副省级城市承担着区域中心的功能,佛山、齐齐哈尔、南通等制造业发达城市是重要节点;(3)五大城市群中珠江三角洲网络密度最高,位于0.324~0.334之间,长江三角洲贸易总流量最高,为783.5亿元,长江中游城市群和成渝城市群网络发育相对滞后;(4)新冠疫情对整体网络的贸易流量和网络结构产生了明显影响,网络社团进一步分化重组,广州—深圳社团明显增强,上海社团明显减弱。研究结果对推动国内大循环和统...  相似文献   

4.
以广东省各地级市辖区和县域中心点为公路网络节点,通过对各节点城市的中心职能强度指数分析及其相互之间在公路网络的连通关系为基础,综合应用日通达性模型、通达性度量模型和潜力模型,对广东区域通达性进行分析,并以不同指标和度量模型的广东区域通达性的空间格局和分异特征进行GIS分析。结果表明,广东省的城市通达性空间格局,总体上呈现出一种圈层空间分布结构,以广州市核心区域和佛山市中心区域(禅城区和顺德区)为中心向外辐射。其影响通达性区域差异的主要因素包括城市经济水平、交通条件和地理区位等,其中,在交通条件影响下的通达性区域差异,在空间上表现出高等级公路网络指向性。研究结果反映出广东省省域公路网络通达性的空间分异规律,诠释了城市的经济发展水平、交通条件和地理区位对通达性的综合作用,从而为广东省城镇网络体系发育、区域经济协调及珠三角产业转移规划优化提供科学支撑。  相似文献   

5.
Based on the National Land Use/Cover Database of China(NLUD-C) in the end of the 1980s(the 1980s,hereafter), 1995, 2000, 2005, and 2010, 665 cities were selected to study the size distribution and its changes of urban lands in China. In this study, the spatiotemporal evolutions of urban land size distribution as well as the influence of administrative-level on these cities were explored by combining urban spatial positions and administrative-levels. Results indicate that: 1) City size distribution using urban lands was more practical and reasonable than using non-agricultural population. 2) In the 1980s, cities with ascending urban land rank were centralized in Eastern China, specially the Changjiang(Yangtze) River Delta, the Zhujiang(Pearl) River Delta, and Beijing-Tianjin-Hebei region. Cities in Central, Western, and Northeast China mainly indicated descending urban land rank. 3) The transfer of national development focus resulted in cities with ascending urban land rank becoming evenly distributed nationwide; however, this trend was slightly centralized around Chengdu, Chongqing, and Wuhan in different periods. 4) During the 1980s to 2010, the proportion of cities with ascending urban land rank in provincial capitals, municipalities, and special administrative regions(high-level cities, hereafter) was consistently higher than those in prefecture- and county-level cities except for 2005–2010. The ranks of the majority of the prefecture- and county-level cities were mainly descending, supported by ascending; the proportion of cities with unchanged rank is small. This study breaks through the bottleneck of traditional research in the area of city size distribution by examining urban land replacing the non-agricultural population. The current study also provides scientific explanation for the healthy and reasonable development of urban land as well as the coordinated development of population urbanization and land urbanization.  相似文献   

6.
通过拟合最优幂函数模型,将NPP-VIIRS影像模拟为DMSP-OLS影像,构建了京津冀、长江三角洲(简称长三角)和珠江三角洲(简称珠三角)三大城市群1992—2017年长时间序列夜间灯光影像集。参考城市建成区统计数据确定夜间灯光最佳阈值提取城市范围,有效剥离统计数据中包含的经济活力不足的城市空间,识别出不属于统计范围的低等级、高活力城镇区,创新了数据应用视角。研究表明:① 县级城镇和市级以上城市对三大城市群城市范围的贡献度不同。京津冀腹地广阔,县级城镇是区域经济活力的重要组成部分,整体上贡献度最大;1990s初期长三角部分县级城镇经济活力较强,大量撤县设市后县级城镇数量减少,逐渐在2005年后低于京津冀;珠三角受到社会经济发展条件和行政单元划分的影响,县级城镇对城市范围的贡献在3个城市群中始终最小。② 三大城市群城市扩展非均衡性特征存在差异。京津冀城市扩展为京、津主导下的“双核”模式,非均衡性显著,尚未形成完善的城市规模体系;长三角和珠三角城市集聚特征明显,均衡性更强。重心迁移的路径、方向和距离反映各城市群不同的扩展强度和作用模式。③ 城市空间扩展格局整体均呈现热点区不断扩大、冷点区不断缩小的特征。其中京津冀热点和冷点区相对稳定,热点区向心集聚作用较强;长三角和珠三角空间格局变化较大,区域核心城市带动作用较强。  相似文献   

7.
铁路客流是城市群内经济社会联系的重要反映,也是区域流空间的关键体现。本文依据流空间理论,采用复杂网络方法和2018年中国铁路班次OD数据,从全国尺度分析城市群社区结构特征,并从城市群尺度比较分析了5个主要城市群的空间结构、规模结构和网络节点结构。结果显示,从铁路客运班次联系来看,城市组团片区与国家规划方案中的城市群在范围上存在一定的空间错位。5个主要城市群具有不同的局部特征:① 长江三角洲城市群呈网络状的空间形态和相对集聚的规模分布,主要问题为局部节点的枢纽作用与规模的匹配性有待提高;② 珠江三角洲城市群呈放射状的空间形态和相对集聚的规模分布,主要问题为与全国其他城市群的联系相对薄弱;③ 京津冀城市群呈放射状的空间形态和相对集聚的规模分布,主要问题为存在边缘化的节点;④ 长江中游城市群呈组团状的空间形态和相对分散的规模分布,主要问题为内部结构较为松散;⑤ 成渝城市群呈哑铃状的空间形态和相对集聚的规模分布,主要问题为与全国其他城市群的联系薄弱。随着区域一体化进程,需要根据不同城市群网络结构发展阶段的差异,补足城市群内和城市群间的联系短板,促进规模位序结构与网络结构的耦合协调,推动建设层次分明、枢纽协作、网络化发展的客运服务网络,支撑城市群一体化发展。  相似文献   

8.
From the ecological viewpoint this paper discusses the urban spatial-temporal relationship.We take regional towns and cities as a complex man-land system of urban eco-community,This complex man-land system comprises two elements of “man“ and “land“,Here,“man“ means organization with self-determined consciousness,and “land“ means the physical environment (niche ) that “man “depends on .The complex man-land system has three basic components,They are individual,population and community,Therefore there are six types of spatial relationship for the complex man-land system.They are individual,population,community,man-man,land-land and man-land spatial realtionships,Taking the Pearl(Zhujiang) River Delta as a case study,the authors found some evidence of the urban spatial relationship from the remote sensing data,Firstly,the concentration and diffusion of the cities spatial relationship was found in the remote sensing imagery,Most of the cities concentrate in the core area of the Pearl River Delta ,but the diffusion situation is also significant ,Secondly,the growth behavior and succession behavior of the urban spatial relationship was found in the remote sensing images comparison with different temporal data ,Thirdly,the inheritance,break ,or meeting emergency behavior was observed from the remoted sensing data.Fourthly,the authors found many cases of symbiosis and competi-tion in the remote sensing data of the Pearl River Delta ,Fifthly,The autoeciousness,stranglehold and invasion behavior of the urban spatial relationship was discovered from the remote sensing data.  相似文献   

9.
城市化进程的加快对区域热环境具有重要影响,热环境的改变会引发一系列生态环境问题,科学地评价城市群热环境安全对于城市发展的规划布局和建设舒适的人居环境具有重要意义。本文利用多期MODIS地表温度数据产品,在构建热环境安全等级分级标准的基础上,对长江三角洲城市群热环境安全格局时空变化特征和土地利用变化的影响进行了探讨。结果表明:① 2015年长江三角洲城市群热环境不安全区域多分布于城市建成区及建成区周围,以南京、上海、杭州和宁波等城市形成的“Z”型区域最明显,临界安全区域多分布于郊区,较安全区域集中分布于长江以北平原区域,安全区域则主要分布于杭州及杭州以南山地、丘陵区,太湖大部分区域以及长江三角洲城市群北部区域;② 2005-2015年长江三角洲城市群热环境不安全区域、临界安全区域、较安全区域和安全区域分别呈现扩张、小幅增长、缩减和先缩减后扩张趋势;③ 土地利用结构中建设用地比例过高和林地比例过低是导致热环境安全等级下降的主要原因,其次,建设用地侵占大量耕地也是导致热环境不安全区域扩张的主要原因。  相似文献   

10.
城市空间格局变化监测能够反映城市建设空间的发展规律和特点,为城镇体系发展规划、优化以及城市空间开发集约利用等提供重要基础。该文选取山东省作为研究区域,以全省17个地级以上城市城区为研究对象和统计分析单元,以2000—2017年7个时期高分辨率正射影像提取其城区边界和部分时期内部结构数据,采用城市扩展面积、城市扩展速度、城市扩展强度及紧凑度等指标,对山东省17个地级市城市空间格局发展变化进行综合分析,对城市扩展、城市用地等进行评价。研究结果表明:山东省地级以上城市空间格局演变整体呈现出以济南青岛为中心的东西两极发展格局,整体发展较为均衡,但东西部差距依然较大。城市紧凑度较低,以粗放型土地增长模式扩展,面积扩张过快,占用耕地比例较高,土地集约利用程度不够。研究成果可为优化城市空间结构,促进城镇高效、集约、节约、绿色发展等提供了合理的建议以及技术支撑。  相似文献   

11.
创新驱动战略的深入推进促使创业型经济繁荣发展,科技型初创企业日益成为促进中国科技进步和经济高质量发展的决定性力量。本文基于2015—2020年中国科技型初创企业数据,运用泰尔指数、核密度估计等方法解析了科技型初创企业的时空格局,并利用OLS模型与SARAR模型定量识别了科技型初创企业分布的影响因素。研究发现:(1)从时间序列来看,2015—2020年中国科技型初创企业的数量快速增长,但是在城市体系的分布呈现持续的层级结构特征;(2)从空间格局看,中国科技型初创企业呈现出以长江三角洲、珠江三角洲为主要核心,京津冀为次要核心的多核心分布模式,创业热点从三大核心扩张到更多地区,东中西三大地带的不平衡性日益增强;(3)风险投资、知识厚度、人力资本、市场规模、孵化环境和政策环境对城市科技型初创企业的发展具有积极影响,创业生态系统的影响也表现出空间依赖性和空间异质性特征,而且不同影响因素的作用强度和相对重要性在不同发展阶段存在差异。未来应重视高质量科技创业生态系统建设,因地制宜地选择适合本地科技型初创企业发展的驱动路径。  相似文献   

12.
随着信息技术的发展,电子商务的盛行推动着快递行业的迅猛发展,快递自提点成为人们日常生活的重要场所,从而成为城市地理与物流地理的重要研究对象。本文基于2018年4月深圳市菜鸟驿站和中国邮政速递物流站点的POI数据,综合运用文本分析、数理统计、空间分析方法,解析深圳市快递自提点的空间分布特征和影响因素。研究发现:① 快递自提点依托类型多样:由市场主导的菜鸟驿站主要依托专业的快递公司、便利店等;由政府主导的邮政站点一般设于中国邮政的分支服务网点;② 快递自提点服务对象种类繁多,二者都主要以服务社区为主,企业、工业园、酒店等为辅;③ 快递自提点的区位选择一般靠近服务对象的出入口,80%的快递自提点分布在距其最近出入口200 m范围内,邮政站点更接近服务对象;④ 快递自提点的空间分布不均衡,呈现“中西部多,东部少”的特点,沿“东-西”走向集聚分布,为多核集聚模式;⑤ 快递自提点的空间格局是区域经济发展水平、人口分布、交通便捷程度、土地利用类型等多因素综合作用的结果,最后探索了快递自提点选址与分布的综合影响机制。  相似文献   

13.
城市的快速扩张不断改变着土地资源的转化,带来了诸多生态环境问题。分析和模拟城市扩张的机制,并对城市未来土地利用变化的风险进行预警,利于合理调控城市的发展。本文提出了一种基于地理分区和未来用地模拟(Future Land Use Simulation,FLUS)模型的城市扩张模拟模型,用于模拟和预测复杂的土地利用变化。该模型利用多指标数据进行空间聚类,耦合地理分区结果进行城市扩张模拟。珠江三角洲2005-2015年的城市扩张模拟结果显示,分区下的模拟精度(FoM=0.2329,提高了9%)明显高于未分区,说明不同分区在土地利用转化上存在空间差异,该模型能更有效地模拟城市土地利用变化。另外,本文构建了一种城市扩张预警指标评价体系,用于评估城市扩张的警情。根据在2005-2015基础上预测的2025-2045年土地利用变化结果,对珠江三角洲城市扩张进行多尺度预警分析。综合预警结果显示该区域大部分城市至2045年城市扩张警情将达到中警和重警,其中东莞警情一直维持在重警。由此,未来需要加强对珠三角城市扩张的宏观调控,以此来缓解未来城市扩张的警情。  相似文献   

14.
1 INTRODUCTION Urban agglomeration researches originated from the concern about the city cluster in the developed areas of western countries. The modern researches have been extended to the specific areas. HALL (2001) summa- rized the generality and difference of urban metropoli- tans in Europe, and analyzed the spatial structure of dif- ferent areas. NAUDE and KRUGELL (2003) analyzed the spatial development of urban agglomeration in South Africa, and thought that the size of the p…  相似文献   

15.
As an important step enhancing regional innovation, researches on collaborative innovation have attracted much more attention recently. One significant reason is that cities can get excessive benefits while they take collaborative innovation activities. Based on the theories of innovation geography, this paper takes the collaborative innovation of the Yangtze River Delta(YRD) Urban Agglomeration as a case study and measures the collaborative innovation capacity from innovation actors and innovation cities by adopting the catastrophe progression model. Then on this basis, the study depicts the spatial pattern and the benefit allocation of collaborative innovation by using the coupling collaborative degree model and benefit allocation model of collaborative innovation. The results show that:1) The collaborative innovation capacity of cities in the Yangtze River Delta has strengthened largely, while the capacity still is not high enough. Cities with high collaborative innovation capacity are concentrated in Shanghai, the southern part of Jiangsu, and Hangzhou Bay, yet the cooperation of the universities-industries-research institutes need to improve. 2) The spatial pattern of collaborative innovation of the Yangtze River Delta presents several innovation circles, which are in Suzhou-Wuxi-Changzhou Metropolitan Circle, Nanjing Metropolitan Circle, Hangzhou Metropolitan Circle, Ningbo Metropolitan Circle, and Hefei Metropolitan Circle. Shanghai plays the role of the central city of collaborative innovation, while Suzhou, Nanjing, Hangzhou, Ningbo, and Hefei act as sub-central cities. 3) The benefit each city allocated from collaborative innovation activities has increased. However, the allocations of the benefit show that cities with higher innovation capacity have significant advantages in most cases, which lead to serious disparities in space.  相似文献   

16.
长江三角洲城市化地区植被初级生产力的时空变化研究   总被引:1,自引:0,他引:1  
城市化过程对植被初级生产具有重要影响。以往研究主要集中于城市用地扩张对植被初级生产力的直接影响分析,而较少关注其间接效果。本文以长江三角洲地区为例,分别从地区尺度和城市尺度分别分析了2000-2013年植被初级生产力的时空变化,探讨了其与气温、降水量及城市建成区绿化覆盖率的关系。研究表明:地区尺度上,2000-2013年长江三角洲植被初级生产力呈现不断增加,其中城市建成区植被初级生产力呈现显著增加的趋势(P<0.05);城市尺度上,城市建成区内植被初级生产力主要呈现增加的趋势,而其外围缓冲区内则与此相反。在当前气候变化背景下,这可能与城市建成区绿化覆盖率不断增加,及快速的城市扩张有关。  相似文献   

17.
黄河三角洲土地生产潜力的GIS评价   总被引:8,自引:0,他引:8  
黄河三角洲可持续发展信息系统数据库的支持下,以黄河三角洲为实验区,考虑影响土地生产力水平的多种因素,确定合理的数学模型,进行土地景观单元的土地生产潜力定量化评价计算。同时,分析了黄河三角洲土地生产潜力的数值分布和空间分布特征以及分级统计和制图,并提出了提高黄河三角洲土地生产潜力的相应建议。  相似文献   

18.
基于CLUE-S模型,以辽河流域为研究区,利用2000年和2010年两期土地利用数据,采用Logistic逐步回归方程ROC曲线,选择高程、距离、土壤等8种驱动因子,对2010年景观格局进行模拟,并依据2010景观格局、相应的辽河流域土地利用规划,设置3种不同情景,进行2010-2020年景观格局模拟。研究表明:(1)模拟的2010年景观格局,kappa精度达到90%以上,表明CLUE-S模型在辽河流域具有良好的景观格局模拟能力。(2)辽河流域在不同情境下,建设用地均出现不同程度的增加,耕地出现不同程度减少。其中,情景2中,森林有所减少,耕地转化幅度较大,建设用地围绕辽河流域城镇带建设逐步扩展,集中在沈阳、抚顺、鞍山等工业发达城市;情景3中,森林、湿地逐步扩大,表现在东部退耕还林,南部紧靠辽海入口湿地增加。研究结论可为未来辽河流域的生态保护建设及景观格局合理规划提供参考依据。  相似文献   

19.
Non-point source (NPS) pollution has become a major source of water pollution. A combination of models would provide the necessary direction and approaches designed to control NPS pollution through land use planning. In this study, NPS pollution load was simulated in urban planning, historic trends and ecological protection land use scenarios based on the Conversion of Land Use and its Effect at Small regional extent (CLUE-S) and Soil and Water Assessment Tool (SWAT) models applied to Hunhe-Taizi River Watershed, Liaoning Province, China. Total nitrogen (TN) and total phosphorus (TP) were chosen as NPS pollution indices. The results of models validation showed that CLUE-S and SWAT models were suitable in the study area. NPS pollution mainly came from dry farmland, paddy, rural and urban areas. The spatial distribution of TN and TP exhibited the same trend in 57 sub-catchments. The TN and TP had the highest NPS pollution load in the western and central plains, which concentrated the urban area and farm land. The NPS pollution load would increase in the urban planning and historic trends scenarios, and would be even higher in the urban planning scenario. How- ever, the NPS pollution load decreased in the ecological protection scenario. The differences observed in the three scenarios indicated that land use had a degree of impact on NPS pollution, which showed that scientific and ecologically sound construction could effec- tively reduce the NPS pollution load in a watershed. This study provides a scientific method for conducting NPS pollution research at the watershed scale, a scientific basis for non-point source pollution control, and a reference for related policy making.  相似文献   

20.
During the past two decades, the exhibition industry in China has been developing rapidly and has become an important part of the modern service industry, particularly the agglomeration characteristics of exhibition enterprises highlighted on the regional scale. Although the development of theoretical research on the western exhibition industry has taken place over time, the spatial perspective has not been at the centre of attention so far. This paper aims to fill this gap and report on the agglomeration characteristics of exhibition enterprises and their influential factors. Based on data about exhibition enterprises in the Pearl River Delta(PRD) during 1991–2013, using the Ripley K function analysis and kernel density estimation, this research identifies that: 1) the exhibition enterprise on the regional scale is significantly characterized by spatial agglomeration, and the agglomeration density and scale are continuously increasing; 2) the spatial pattern of agglomeration has developed from a single-center to multi-center form. Meanwhile, this paper profiles the factors influencing the spatial agglomeration of exhibition enterprises by selecting the panel data of nine cities in the PRD in 1999, 2002, 2006 and 2013. The results show that market capacity, urban informatization level and exhibition venues significantly influence the location choice of exhibition enterprises. Among them, the market capacity is a variable that exerts a far greater impact than other factors do.  相似文献   

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