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1.
Land use and land cover change (LULCC) dynamics have been particularly strong in the Mediterranean region, due to its historical development and to agro-pedoclimatic conditions favorable to human settlement. This area has undergone in the 1950s and the 1980s intense urbanization processes that has followed different trajectories. Urban expansion commonly occurs at the expense of agricultural land, leading to the fragmentation of natural areas and conflicts over access to land resources. These dynamics mainly concern the fringe between urban and agricultural land, e.g. the peri-urban areas usually included within functional urban regions. Here, to identify common features of LULCC in Western Mediterranean urban regions, we investigated two main features: direct changes due to urbanization and indirect changes affecting non-artificial land uses. We compared LULCC dynamics in 6 case studies from the north and south of the Western Mediterranean region: the urban regions of Montpellier and Avignon (France), Pisa (Italy), Madrid (Spain), Meknes (Morocco), and Constantine (Algeria), using a 30-year multitemporal spatial analysis (1980–2010). Two series of Landsat TM images were acquired for each case study and land cover data were analyzed both for dynamics and for land patterns, using landscape and class metrics. We found no significant north-south differences in LULCC dynamics between the investigated Western Mediterranean urban regions. Differences are more pronounced between small–medium cities and large metropolitan areas in type of urban diffusion, which is more sprawled in small–medium cities and more compact in large metropolitan areas. Rather, differences occur in LULCC not directly affected by urbanization, since in Northern Mediterranean urban regions afforestation and abandonment of agricultural areas are prevalent and closer to the urban areas, whereas transformation of natural areas into agricultural ones occurs mainly in Southern Mediterranean urban regions at a similar distance from urban areas than it happens for afforested or abandoned areas. In attempting for the first time to assess LULCC in these Mediterranean urban regions, we provide a preliminary comprehensive analysis that can contribute to the active LULCC research in the Mediterranean basin and that can be easily applied to other Mediterranean urban regions.  相似文献   

2.
廖继武  孙武  尹秋菊  李森 《热带地理》2004,24(3):260-264
海南西部因其独特的位置而具有与海南其他地方显著不同的脆弱的自然环境.城镇的形成和扩张引起周围地区土地利用的巨大变化,尤其是风沙化土地和耕地在城镇发展的不同时期表现出不同的变化特征.城镇建设、人口增加、水利和防护林建设是土地利用变化的主要驱动力.  相似文献   

3.
经济核心区是国家和地区经济增长、城市化发展的主要空间,也是城市蔓延最为严峻的区域。长(春)吉(林)一体化地区是中国图们江区域合作开发开放的先导区和东北地区的粮食主产区,肩负着“经济增长”、“人口城镇化”和“粮食安全”等多重责任。基于2000、2005、2009年的遥感图像和相关年份的统计年鉴,结合GIS和SPSS统计工具,对长、吉城市蔓延的程度、方式、效应与驱动力因子进行了比较分析。结果表明:用地扩展水平上长春市明显强于吉林市,且吉林市还表现出明显的阶段性特征;蔓延程度上,两市都表现出集约度低下、蔓延程度大的特性;蔓延方式上,长春市以“近域推进”式蔓延为主,吉林市以“轴带扩展”式蔓延为主;蔓延效应上,都带来了一系列负面效应,但长春市程度要重;在蔓延驱动力上,工业化和投资拉动是两者共同的主导影响因子,带有明显的政府导向性特征。文中提倡城市内部土地节约集约利用、区际培育城市群以形成合理的城市规模。  相似文献   

4.
Rapid peri-urbanization has become a new challenge for sustainable urban-rural development worldwide. To clarify how unprecedented urban sprawl at the metropolitan fringe impacts urban-rural landscape, this study took the Beijing-Tianjin corridor of Beijing-Tianjin-Hebei metropolitan area, one of the largest urban clusters in China, as a typical example. By using Landsat-based landscape metrics and a practical methodology, we investigated the landscape changes and discussed the potential reasons in the context of rapid peri-urbanization of China. Specifically, multi-temporal land use maps derived from Landsat images were used to calculate landscape metrics and analyze their characteristics along the urban-rural gradients. The practical methodology was used to monitor spatio-temporal characteristics of landscape change in large metropolitan areas. The results showed that landscape patterns in the area had changed greatly from 2000 to 2015 with characteristics of construction land sprawl and arable land shrinkage. The intensity and scale of landscape changes varied along the urban-rural gradients. Sampled plots in urbanized areas and rural areas demonstrated distinguishable landscape patterns and significant differences. Urban areas had more heterogeneous and fragmented landscapes than rural areas. Peri-urban areas in general experienced higher levels of land diversification than rural areas. Rural residential land appeared to be more aggregated near Beijing and Tianjin cities. Besides, our findings also indicated that urban expansion was largely responsible for landscape patterns.The findings of this study potentially provide strategical insights into landscape planning around mega cities and sustainable coordinated urban-rural development.  相似文献   

5.
基于GIS的石家庄市城市土地利用扩展分析   总被引:32,自引:11,他引:21  
根据石家庄市多年的图文资料、城市土地利用数据等大量信息,运用GIS技术,分析1934年至2001年的发展过程中,城市土地利用的时空演变特征与规律,并简要分析城市扩展的主要原因及所导致的环境影响。得出以下结论:石家庄市城市用地在时间上具有快慢交替的4个成长阶段和空间上的3种扩展模式。其发展具有圈层式向外扩展、扩展高速区域沿京广铁路线东西摆动的特点;人口、政策及交通条件等是影响城市用地扩展的主要原因。  相似文献   

6.
试论城市建设中研究埋藏地貌的意义——以南京市为例   总被引:2,自引:2,他引:0  
潘凤英 《地理研究》1988,7(1):65-72
从今后城市化发展的趋势出发,山城市建设地基条件、城区找水、抗震等入手论述了研究埋藏地貌的意义和作用。  相似文献   

7.
Lack of agreement on how to define and measure sprawl has hampered development of policy related to its causes and consequences. We question previous work for two reasons: the use of study areas that overbound or underbound sprawl landscapes, and the failure to account for land unavailable for development. We formulate “extended urban areas,” based on housing density and commuting patterns and argue that they represent a preferable geographic basis for measuring sprawl. We operationalize with satellite imagery a way for measuring land unavailable for development in these areas. We then compute five measures of urban development using the National Land Cover Data Base and decennial census data to assess the extent of sprawl in the extended urban areas of Atlanta, Baltimore, Boston, Los Angeles, and Washington. Our sensitivity analyses reveal that the measurement of sprawl critically depends on which land area forms the basis of the analysis, and, to a lesser degree, how one accounts for land unavailable for development.  相似文献   

8.
Sprawling urban development is a major driving force of landscape fragmentation and loss of agricultural land. Despite this understanding, science has yet to realize a coherent suite of methods to analyze all circumstances of sprawl. Consequently, this paper contributes to this realization by combining three methods to address sprawl in a small US metropolitan area – Centre County, Pennsylvania: cross-tabulation to identify systematic non-random land use transitions; logistic regression to determine explanatory variables of urban land use location resulting from these transitions; and the CLUE-S regional modeling framework to project future urban land use patterns in the county. The results demonstrate the versatility of the methodology because of its ability to detect land use change despite the large proportion of the landscape that remained uncharged during the two periods under consideration, and because of its ability to distinguish systematic non-random land use transitions from random ones. The strength of the methodology is further demonstrated by its capability to allocate land use change according to change in land use location as well as to net change in land use quantity. The methodology identified soil and topography as the primary explanatory drivers of urban land use location in Centre County. Although the model is able to simulate urban land use location at the county level, it is less able to simulate these locations at the sub-county level, thereby suggesting that the explanatory variables for urban land location are not fully captured at this scale. Overall, the methodology for sprawl analyses presented in the study is robust and adds to the tools available to decision makers for assessing sprawl dynamics.  相似文献   

9.
长江三角洲地区城镇时空动态格局及其环境效应   总被引:28,自引:10,他引:18  
何剑锋  庄大方 《地理研究》2006,25(3):388-396
利用多期遥感影像对长江三角洲地区城镇近15年来的时空变化特征进行了分析,揭示了地区城镇化的空间格局与其生态环境的相互关系。结果表明:80年代中后期至2000年之间以农业景观为主的农田、林地显著减少,城镇迅速扩张,呈集中化趋势。前后五年的土地利用动态变化的构成比例不同,后期城市扩展的速度明显减慢。土地利用的动态变化引起了环境的一系列变化,其扩展方式直接影响到局地气候及区域空气质量。  相似文献   

10.
在经济高质量发展和区域协调发展的背景下,考虑非期望性产出(环境污染),本文利用SBM-undesirable模型测算了中国275个地级市2003–2016年的城市土地利用效率,并通过核密度估计、空间自相关分析探索了城市土地利用效率的时空演变规律。结果表明:(1)2003–2016年间,中国城市土地利用效率整体呈波动上升趋势,但仍处于较低水平,城市土地利用效率均值呈现东、西、中逐渐降低的分布格局;(2)在全国和东中西三大区域,区域差异均不断增大,全国尺度上和东部地区效率值出现了极化趋势;(3)城市土地利用效率呈现较弱的空间正相关,但空间集聚程度不断增强。高-高集聚型区域多分布在东南沿海地区,且不断向中部地区延伸;高-低极化型区域多为中西部地区的省会城市,低-高凹陷型区域零星分布于高值聚集区周边,部分在研究期内转为高值聚集区域;低-低均质型区域主要分布在中西部及东北地区。研究结果认为应加强对城市存量土地的内涵挖潜,强化区域合作机制,因地制宜制定提升土地利用效率的政策是促进城市土地集约节约利用和区域协调发展的有效路径。  相似文献   

11.
This article explores the use of nighttime satellite imagery for mapping urban and peri-urban areas of Australia. A population-weighted measure of urban sprawl is used to characterize relative levels of sprawl for Australia's urban areas. In addition, the expansive areas of low light surrounding most major metropolitan areas are used to map the urban–bush interface of exurban land use. Our findings suggest that 82 percent of the Australian population lives in urban areas, 15 percent live in peri-urban or exurban areas, and 3 percent live in rural areas. This represents a significantly more concentrated human settlement pattern than presently exists in the United States.  相似文献   

12.
王磊  段学军 《地理科学》2010,30(5):702-709
城市化是建设用地扩展的主要驱动因素,分析建设用地时空演化格局已成为学者研究城市化过程的重要视角。采用空间自相关等方法,测度了1985年以来长江三角洲地区城市空间扩展的集聚特征并分析其演变过程;并结合格网建设用地密度频率的变化特点,将空间划分为不同的景观梯度地带,以此研究城市空间在不同地带中的扩展特点。研究结果表明,长三角城市空间扩展聚集程度先降后升,城市化区域融合趋势明显,并在城市空间扩展中表现出以上海、南京和苏州等为代表的3种模式,反应了长三角内部不同的经济发展特点。此外,在不同景观梯度下,长三角城市空间扩展表现出典型的阶段性特征。2000年以前在各个景观梯度下城市空间扩展差异较小,表现为较强的拓展性扩展;2000年以后,在城市核心区扩展强度加强,表现为填充式扩展加快。同时,城乡过渡区面积增加迅速,表明随着城市空间扩展的加速,长江三角洲地区城市土地不集约利用现象已较为突出。  相似文献   

13.
城市土地可持续利用中的环境工程地质研究   总被引:2,自引:0,他引:2  
土地资源是人类赖以生态的不可再生的资源,是人类社会可持续发展的基础,但目前城市土地开发中不仅造成日益严重的环境问题,也对土地资源造成很大的浪费。为了合理利用城市每寸土地,文章分析了城市化进程中土地利用的基本问题,研究城市土地开发中引起的主要环境工程地质问题,并从环境工程地质学的角度,探讨了城市土地可持续利用的途径与措施。  相似文献   

14.
北京城市蔓延的测度与分析   总被引:12,自引:0,他引:12  
蒋芳  刘盛和  袁弘 《地理学报》2007,62(6):649-658
针对现阶段我国城市用地快速扩张和无序蔓延的现实问题, 以北京市在1996~2004 年期间的城市扩展作为研究案例, 提出可以从城市扩展形态、扩展效率和外部影响等三个方面来判识城市蔓延现象, 并提出基于地理空间指标体系的城市蔓延测度方法, 主要由涉及人口、经济、土地利用、农业、环境和城市生活等方面的13 项指标所组成。实证分析结果表明, 该方法可以有效地测度和量化研究区城市蔓延的特征: ① 建设用地斑块具有明显的破碎化和不规则化趋势, 缺乏良好的规划控制, 不连续开发、条带式开发和跳跃式开发特征明显, 扩展形态不尽合理; ② 新增建设用地的建设密度和容积率较低, 并且新增用地的人口密度和经济产出水平均低于原有用地绩效, 扩展效率不高; ③ 城市蔓延占用大量的耕地和开敞空间、加重了交通负担, 对农业、环境和城市生活存在显著的负面影响。  相似文献   

15.
Urban sprawl has become a global phenomenon as an outcome of growing population and rapid urbanization. Previous studies have addressed the rising incidence of uncontrollable urban development, particularly in peri-urban areas of cities, leading to chronic urban sprawl. The city of Guwahati, a million city in north east India, has expanded significantly in recent years. In this article, the links between population and growth of built-up areas were examined using geo-spatial techniques and remotely sensed datasets. The results indicate that the sprawl has accentuated in recent years. The intensity of land use remained uneven due to marked variations in the distribution of built-up areas, plausibly an outcome of unplanned urban growth. If current trends are anything to go by, future urban sprawl could pose serious threats to the vulnerable eco-sensitive and peri-urban areas of Guwahati. Secondary cities have unfortunately received scant attention in urban policy research, and Guwahati, epitomizes urban woes in a developing country.  相似文献   

16.
Difficulties in identifying actual uses of land space from remote sensing-based land cover products often result in lost opportunities to enhance the capacity of applied research on human settlements. In an attempt to address these difficulties, this study investigates how land cover and land use are interrelated with each other and what determines the relationship patterns by analyzing detailed land use and land cover data for two large US metropolitan areas – the five-county Los Angeles and six-county Chicago regions – where a broad spectrum of human settlements, ranging from urban cores to less-urbanized edges, coexist. The analysis shows that the land cover-land use relationship substantially varies not only across regions but across neighborhoods within each region. Through multivariate regression, it is also found that the intraregional variation is highly associated with the neighborhood's stage of urbanization, median housing age, and other development characteristics, suggesting that the relationship pattern can largely be shaped by the history and evolution of urban design/development.  相似文献   

17.
北京城市蔓延的测度与分析   总被引:5,自引:2,他引:3  
Concerning about the rapid urban growth in recent China, this study takes Beijing as a case and puts forward that urban sprawl can be measured from spatial configuration, urban growth efficiency and external impacts, and then develops a geo-spatial indices system for measuring sprawl, a total of 13 indicators. In order to calculate these indices, different sources data are selected, including land use maps, former land use planning, land price and floor-area-ratio samples, digitized map of the highways and city centers, population and GDP statistical data, etc. Various GIS spatial analysis methods are used to spatialize these indices into 100m×100m cells. Besides, an integrated urban sprawl index is calculated by weight sum of these 13 indices. The application result indicates that geo-spatial indices system can capture most of the typical features and interior differentia of urban sprawl. Construction land in Beijing has kept fast growing with large amount, low efficiency and disordered spatial configuration, indicating a typical sprawling tendency. The following specific sprawl features are identified by each indicator: (1) typical spatial configuration of sprawling: obvious fragmentation and irregularity of landscape due to unsuccessful enforcement of land use planning, unadvisable pattern of typical discontinuous development, strip development and leapfrog development; (2) low efficiency of sprawl: low development density, low population density and economic output in newly developed area; and (3) negative impacts on agriculture, environment and city life. According to the integrated sprawl index, the sprawling amount in the northern part is larger than that in the southern, but the sprawling extent is in converse case; most sprawling area include the marginal area of the near suburbs and the area between highways, etc. Four sprawling patterns are identified: randomly expansion at urban fringe, strip development along or between highways, scattered development of industrial land, leapfrog development of urban residence and industrial area.  相似文献   

18.
设计城市地貌图应注重城市地貌在建城区、边缘区和城市经济辐射区范围内的区域分异规律。编制城市地貌图应遵循:环境功能,应用性,突出重点和图面协调三个原则。据此编制了成都市1:6500建城区,1:5万边缘区和1:20万城市经济辐射区三种城市地貌图。  相似文献   

19.
Land use change and its eco-environmental responses are foci in geographical research. As a region with uneven economic development, land use change and eco-environmental responses across Jiangsu Province are relevant to China’s overall development pattern. The external function of regional land use changes during different stages of economic development. In this study, we proposed a novel classification system based on the dominant function of land use according to “production-ecology-life”, and then analyzed land use change and regional eco-environmental responses from a functional perspective of regional development. The results showed that from 1985 to 2008, land use change features in Jiangsu were that productive land area decreased and ecological and living land areas increased. Land use changes in southern Jiangsu were the most dramatic. In southern and central parts of Jiangsu the agricultural production function weakened and urban life service function strengthened; in northern Jiangsu, the mining production function’s comparative advantage highlighted that the rural life service function was weakening. Ecological environmental quality decreased slightly in Jiangsu and its three regions. The maximum contribution rate to ecological environmental change occurred in southern Jiangsu and the minimum rate was located in the north. Eco-environmental quality deteriorated in southern and central Jiangsu, related to expanding construction land in urban and rural areas. Ecological environmental quality deterioration in northern Jiangsu is probably due to land development and consolidation. The main reason for improvements in regional ecological environments is that agricultural production land was converted to water ecological land across Jiangsu.  相似文献   

20.
张潇  谷人旭 《地理研究》2022,41(5):1311-1326
科学刻画与模拟土地利用冲突的时空演化格局是精准认知区域土地利用结构进而寻求人地关系协调的基础。采用景观格局指数构建土地利用冲突模型,借助GIS等手段分析长江三角洲城市群1980—2020年间土地利用冲突的时空演化特征,并结合斑块生成土地利用变化模拟模型和多目标规划法多情景模拟2035年的土地利用冲突格局。结果表明:①长江三角洲城市群土地利用冲突受地形等因素影响呈现“北高南低”的分布格局,且在高速城镇化和城市无序蔓延等因素作用下,人地关系趋于不协调发展,土地利用冲突程度逐年加剧。②受人口迁徙和城镇化发展阶段的影响,土地利用冲突的热点区域由乡村空间转移至了城市空间。③在土地利用过程中,耕地是各利益主体争夺的核心区域,也是权衡土地利用冲突的“关键地带”。④可持续发展情景兼顾了经济发展与生态保护两方面的用地需求,是缓和土地利用冲突的一种合理选择。  相似文献   

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