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1.
青藏高原城镇体系的时空演变   总被引:1,自引:0,他引:1  
城镇体系的形成和发育对区域城镇化进程及社会经济发展起着至关重要的作用,并对生态环境产生重要影响。青藏高原特殊的地理环境与相对落后的社会经济基础,导致城镇体系不甚健全。目前国内外相关研究薄弱,不利于国家生态安全屏障建设及青藏高原可持续发展。为此,本文以建制镇以上的镇区和城市市区为研究对象,结合统计数据与遥感数据,借助GIS空间分析方法对青藏高原1990-2015年城镇体系的空间结构和规模结构进行时空演变格局分析,并采用重心移动模型揭示了青藏高原城镇人口规模和用地规模重心的迁移规律。结果表明:青藏高原城镇空间分布总体呈现出“东南密集、西北稀疏”、“大分散、小集聚”的格局;城镇分布在时间上具有阶段性增长特征且总体趋于集聚,在空间上不均衡程度呈上升趋势但2005年后明显减缓;虽然建制镇数量大幅增长,但96.88%的城镇规模在5万人以下,大中小城市发育不足;城镇人口规模重心呈现“先向西南,再向东北,又向西南”的移动轨迹;城镇用地规模重心呈现“先向东南,再向西北,再向东北”的迁移趋势。本文研究了青藏高原城镇体系的规模结构及其时空演变特征,为青藏高原新型城镇化及城镇空间格局优化提供基础依据;提出了资料缺乏和统计口径不一致的条件下城镇规模的合理估算方法,对我国城镇化相关研究具有一定的参考价值。  相似文献   

2.
伴随新型城镇化进程的不断推进,城市群已经成为地区社会经济发展的重要核心。大数据时代的到来促使新兴时空大数据在城市/城市群建设与管理中发挥着重要作用,并成为当前学术界的研究热点。大数据挖掘技术与融合分析技术将成为未来研究城市群的重要方法。本研究总结归纳了时空大数据在城市群建设与管理中的应用研究进展,对常见城市群时空大数据类型、获取方法和分析技术进行分类整理,并对基于资源调查和多源时空数据分析的城市/城市群研究进展进行分析,特别是对时空大数据及其技术在城市群建设与管理中的主要研究展开归类分析,认为目前时空大数据在城市群建设与管理应用领域主要涉及5大方向:城市群空间界定与发展监测、交通网络监测、关联性分析与功能布局评价、产业协同分析和环境监测与评估。最后,本文分析了现阶段时空大数据在城市群建设与管理应用中的发展瓶颈,提出了相关对策建议,并对未来研究发展趋势提出了展望。  相似文献   

3.
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   

4.
从道路网络的形态特征和拓扑特征两方面,对武汉城市圈公路交通网络结构进行定量研究。根据1990~2012年的动态变化过程分析结果显示,近20年来武汉城市圈的公路交通有了很大发展,道路规模显示"早期重点发展、后期均衡发展"的趋势,在空间上显示"总体稳步集中,局部先集聚后分散"的规律,以后的道路建设应从规模扩张的发展趋势转向结构优化的发展策略。  相似文献   

5.
本文基于Landsat-5TM和Landsat-8OLI遥感影像,利用支持向量机分类方法提取2000、2005、2010、2015、2020年5个时期的哈-长城市群建设用地信息,选取扩张速度、扩张强度、弹性系数等参数探讨哈-长城市群20年来建设用地扩张进程在时间维度上的变化特征.研究结果表明:2000―2020年哈-长城市群建设用地增加了15956.58km2,扩张速度先慢后快,整体扩张强度呈上升趋势;2015―2020年是扩张速度最快且扩张强度最大的时间段,扩张速度达到13.15%,扩张系数达到0.59,属于中速扩张阶段;哈-长城市群建设用地在扩张过程中弹性系数超出了合理值1.12,呈现不合理的态势,土地集约利用化程度不高,人地关系整体不协调.  相似文献   

6.
Local climate zones(LCZs) are an effective nexus linking internal urban structures to the local climate and have been widely used to study urban thermal environment. However, few studies considered how much the temperature changed due to LCZs transformation and their synergy. This paper quantified the change of urban land surface temperature(LST) in LCZs transformation process by combining the land use transfer matrix with zonal statistics method during 2000–2019 in the Xi’an metropolitan. The r...  相似文献   

7.
It is crucial to investigate the urban agglomerations spatio-temporal evolution patterns and driving factors for analyzing the urban spatial structure-functional division and promoting the coordinated development of urban agglomerations. In this study, a novel vegetation-building-nighttime light-adjusted index(VBNAI) was established for rapid and effective mapping of urban construction land(UCL) in Central Plains Urban Agglomeration(CPUA), China during 2000–2020 based on Google Earth Engine(GEE)...  相似文献   

8.
探究城镇空间扩张的方向性及其时间变化特征,能够反映都市圈发展过程中核心城市与边缘地区空间关联的动态过程,为制定都市圈发展的相关政策提供科学依据。本文从都市圈的核心城市与边缘地区相互关联的视角,借鉴物理学中力的分解原理,构建了同时兼顾扩张强度和方向性的向心扩张指数CEI,并以郑州都市圈为对象,采用2000—2018年30 m分辨率的全球人造不透水面数据产品GAIA,分析了建设用地扩张的总体数量和占比变化、动态度及强度变化、以及空间方向性变化等特征,进一步应用多元逻辑回归模型,揭示了影响城镇空间扩张向心性的关键因素。结果表明:(1)向心扩张指数CEI为揭示都市圈核心城市对边缘地区的辐射带动作用提供方法支撑,能够定量刻画边缘地区朝向核心城市的发展趋势;(2)在郑州都市圈近20年的快速扩张过程中,尽管各区县市的DEI指数和CEI指数随时间而增减波动,但郑州都市圈总体呈现“核心—边缘”发展模式,除个别地级市中心城区及其下辖县以外,多数区县市的向心性显著且随时间增强,郑州市中心城区对于边缘地区具有显著的辐射带动作用;(3)核心城市与边缘地区的人均GDP差异及城镇化率差异是影响边缘地区向心扩张的重要...  相似文献   

9.
成都市热岛效应与城市空间发展关系分析   总被引:2,自引:0,他引:2  
利用Landsat卫星影像反演成都市中心城区1992、2001和2009年的地表温度,建筑用地和植被等信息,计算其城市热岛比例指数(URI),对成都市中心城区热岛效应与城市空间发展关系进行了分析。结果表明,在1992-2009年期间成都市主城区范围从91.24km2扩展到403.8km2。成都市建成区的大面积扩展导致了城市热岛空间分布发生迁移,从单中心聚集分布转变为多中心环状分布。回归分析说明,建筑用地和植被都是影响地表温度的重要因素,其中建筑用地与地表温度呈指数型正相关关系,而植被与地表温度呈负相关关系。总的看来,成都市中心城区在这17年间的热岛效应有了明显的缓解,城市热岛比例指数从0.72下降到0.33。城市植被覆盖率的增加和合理的规划对缓解城市热岛效应起到了积极的作用。  相似文献   

10.
Urbanization,especially urban land expansion,has a profound influence on the urban thermal environment.Cities in Northeast China face remarkably uneven development and environmental issues,and thus it is necessary to strengthen the diagnosis of thermal environmental pressure brought by urbanization.In this study,multi remote sensing imageries and statistical approaches,involving piecewise linear regression(PLR),were used to explore urban expansion and its effects on the thermal environment of Changchun City in Jilin Province,China.Results show that Changchun experienced rapid urban expansion from 2000 to 2020,with urban built-up areas increasing from 171.77 to 525.14 km2.The area of the city’s urban heat island(UHI)increased dramatically,during both day and night.Using PLR,a positive linear correlation of built-up density with land surface temperature(LST)was detected,with critical breakpoints of 70%-80%during the daytime and 40%-50%at nighttime.Above the thresholds,the magnitude of LST in response to built-up density significantly increased with intensifying urbanization,especially for nighttime LST.An analysis of the relative frequency distributions(RFDs)of LST reveals that rapid urbanization resulted in a significant increase of mean LST in newly urbanized areas,but had weak effects on daytime LST change in existing urban area.Urban expansion also contributed to a constant decrease of spatial heterogeneity of LST in existing urban area,especially at daytime.However,in newly urbanized areas,the spatial heterogeneity of LST was decreased during the daytime but increased at nighttime due to urbanization.  相似文献   

11.
Urban areas and its evolution are important anthropogenic indicators and human ecological footprints, and play decisive roles in environmental change analysis, global geo-conditional monitoring, and sustainable development. China has the highest rate of urban expansion and has emerged as an urban expansion hotspot worldwide. In this paper, the progress of studies on Chinese urban expansion based on remote sensing technology are summarized and analyzed from the aspects of urban area definition, remotely sensed imagery applied in urban expansion, monitoring methods of urban expansion, and urban expansion applications. Existing issues and future directions of Chinese urban expansion are discussed and proposed. Results indicate that: 1) The fusion of multi-source remotely sensed imagery is imperative to meet the needs of urban expansion with various monitoring terms and frequencies on different scales and dimensions. 2) To guarantee the classification accuracy and efficiency and describe urban expansion and its influences on local land use simultaneously, the combination of visual interpretation and automatic classification is the tendency of future monitoring methods of urban areas. 3) Urban expansion data have become the prerequisite for recognizing the urban development process, excavating its driving forces, simulating and predicting the future development directions, and also is conducive to revealing and explaining urban ecological and environmental issues. 4) In the past decades, Chinese scholars have promoted the application of remote sensing technology in the urban expansion field, with data construction, methods and models developing from the quotation stage to improvement and innovation stage; however, an independent and consistent urban expansion data on the national scale with long-term and high-frequency (such as annual monitoring) monitoring is still lacking.  相似文献   

12.
In this paper, we use factor analysis to evaluate the urban comprehensive quality of each city in the Lanzhou-Xining(Lan-Xi) urban agglomeration. The time distance was obtained by using GIS spatial analysis, and the structure and pattern of the spatial network were analyzed by using the gravity model and social network analysis method. The results show that: 1) The scale effect of the Lan-Xi urban agglomeration is gradually emerging, and it is gradually forming the urban agglomeration with Lanzhou and Xining as the core, the Lan-Xi high-speed railway as the axis, and a high-dense connection. 2) Lanzhou and Xining are at the core of the Lan-Xi urban agglomeration, which has a strong attraction and spreads to neighboring cities. 3) In the network structure of the Lan-Xi urban agglomeration, Lanzhou, Baiyin, Gaolan, Yuzhong, Yongdeng, Dingxi, Lintao, Xining, Ledu, Huangzhong, Ping'an, Minhe and Datong are located in the network core position, which have the superiority position and lead to the entire regional communication enhancement and the regional integration development. 4) This urban agglomeration has significant subgroups, eight tertiary subgroups and four secondary subgroup; the tertiary subgroups which compose secondary subgroup have a close connection and mutually influence each other. 5) The Lanzhou Metropolitan Area and the Xining Metropolitan Area have an important impact on the surrounding cities, and the peripheral cities are basically controlled by the central city. The Dingxi subgroup, Lintao-Linxia subgroup, Gonghe subgroup have more structural holes than the subgroups within the Lanzhou Metropolitan Area and the Xining Metropolitan Area, so the peripheral cities of these subgroups have relatively less connection with surrounding cities.  相似文献   

13.
基于人文地理视角下的城市创意产业图像可视化分析对城市深层次空间综合和区域创新发展具有重大意义。但Swarm群智能动态时空建模难以满足创意产业空间集聚的可视化发展。本文研究目标是,从城市区域创意产业空间聚类影响因素指标出发,创新性地提出区域空间动态集聚轨迹算法(Density-Based Interest Spatial Clustering of Path,DBICP),并与计算机浏览器共建聚类可视化图像,为城市管理提供决策依据。首先,根据影响因素指标体系,利用2014—2018年空间卡口流量数据和产业指标数据进行预处理,构建空间标准聚类算法DBSCAN。然后,对其进行聚类密度分级优化形成全新DBICP算法并得出初步轨迹图像。最后,通过源码转译实现了浏览器界面下空间动态集聚轨迹图像的输出。结果表明:以上海市为例,普陀区、浦东新区、徐汇地区的创意产业空间分布形成了3种不同的聚类模式,并相应提出了分摊、均布、虹吸的管控策略。此方法克服了传统图像的聚类分级和轨迹测量的缺失,可以有效地从指标数据中发现图像轨迹聚类信息,体现了地理信息科学和人文社会学科的交叉融合。也为大数据动态图像的集聚方法提供了全新视角和借鉴价值。  相似文献   

14.
采用可达性水平评价、经济联系分析、块模型等方法,研究了2009、2018年长江中游城市群的铁路可达性和经济联系空间格局,结果显示:从2009到2018年,长江中游城市群的铁路可达性改善明显,城市通达度提升,中心城市日常可达性范围扩大,尤其是1 h经济圈扩张明显,各城市的加权平均旅行时间显著降低,呈现"核心-边缘"格局,但差异增大;长江中游城市群形成以武汉、长沙、南昌为核心的放射状经济联系空间格局,且武汉、长沙的中心作用较南昌更明显,主要高铁沿线形成较高水平的经济联系带,剩余绝大多数城市间经济联系水平较低;长江中游城市群可划分为4个凝聚子群,其中环长株潭子群、武汉城市圈子群内部经济联系较强,4个子群内部联系显著高于相互联系,区域网络化格局尚未形成.  相似文献   

15.
以南京市为研究区域,基于Landsat系列影像,采用单窗算法反演南京市2000—2017年的地表温度.通过地表温度均值标准差法划分城市热岛等级,分析南京市城市热岛时空演变特征,并基于归一化植被指数(NDVI)和归一化建筑指数(NDBI),分析南京市城市热岛和植被覆盖及不透水面的关系.研究结果表明,南京市2000—2017年城市热岛现象明显且有逐渐增长趋势;南京市城市热岛与植被覆盖、城市不透水面表现出较强的空间一致性;南京市城市热岛与植被覆盖和不透水面分别呈现负相关和正相关关系.研究为南京市城市环境管理与城市合理规划提供了一定的理论依据与参考.  相似文献   

16.
以山东省淄博市1981-2005年城市建设用地统计数据为研究基础,运用主成分分析法和定性分析法,研究该地区城市建设用地扩展的特征和影响机制。1980年以来淄博市城市建设用地分为平稳扩展、加速扩展和快速扩展3个时期。淄博市城市建设用地扩展的主要影响因素是制度改革、经济发展和人口增长。国家财税、土地等制度改革影响了经济的发展,而经济发展是城市建设用地扩展的根本驱动力。  相似文献   

17.
In this study, we developed an evaluation index system for green total-factor water-use efficiency(GTFWUE) which reflected both economic and green efficiencies of water resource utilization. Then we measured the GTFWUE of 30 provinces/municipalities/autonomous regions(hereafter provinces) in China(not including Tibet, Hong Kong, Macao, Taiwan as no data) from 2000 to 2018 using a minimum distance to the strong frontier model that contained an undesirable output. We further analyzed the regional ...  相似文献   

18.
随着快速的城镇化进程,PM2.5带来的污染越来越严重,在一定程度上影响了城市的发展.所以本文从探讨城市扩展模式与PM2.5关系这一视角出发,利用景观扩展指数识别2005—2015年中国城市建设用地的扩展类型,并通过裁剪PM2.5数据,在国家、地区和省级3个尺度内探究PM2.5的分布情况.最后采用OLS模型和GWR模型进...  相似文献   

19.
Rapid urbanization leads to dramatic changes in land use patterns, and the land use/cover change(LUCC) can reflect the spatial impact of urbanization on the ecological environment. Simulating the process of LUCC and predicting the ecological risk future changes can provide supports for urban ecological management. Taking the Yangtze River Delta Urban Agglomeration(YRDUA),China as the study area, four developmental scenarios were set on the basis of the land use data from 2005 to 2015. The tempor...  相似文献   

20.
Characteristics of air pollution in Northeast China(NEC) received less research attention in the past comparing to other heavily polluted regions in China.Spatiotemporal variations of six criteria air pollutants(PM_(10), PM_(2.5), SO_2, NO_2, O_3 and CO) in Central Liaoning Urban Agglomeration(CLUA) and Harbin-Changchun Urban Agglomeration(HCUA) in NEC Plain were analyzed in this study based on three-year hourly observations of air pollutants and meteorological variables from 2015 to 2017.The results indicated that the annual mean concentrations of air pollutants are generally higher in the middle and southern regions in NEC Plain and lower in the northern region.Megacities such as Shenyang, Harbin and Changchun experience severe air pollution, with a three-year averaged air quality index(AQI) larger than 80, far exceeding the daily AQI standard at the first-level of 50 in China.The annual mean PM and SO_2 concentrations decrease most significantly in NEC urban agglomerations from 2015 to 2017, followed by CO and NO_2, while O_3 shows a slight increasing trend.All the six pollutants exhibit obvious seasonal and diurnal variations, and these variations are dictated by local emission and meteorological conditions.PM_(2.5) and O_3 concentrations in NEC urban agglomerations strongly depend on wind conditions.High O_3 concentrations at different cities usually occur in presence of strong winds but are independent on wind direction(WD), while high PM_(2.5) is usually accompanied by weak winds and poor dispersion condition, and sometimes also occur when the northerly or southerly winds are strong.Regional transport of air pollutants between NEC urban agglomerations is common.A severe haze event on November 1–4, 2017 is examined to demonstrate the role of regional transport on pollution.  相似文献   

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