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1.
快速城市化显著改变了城市下垫面空间特征,对地表产汇流过程产生了重要影响。综述城市下垫面空间特征对地表产汇流过程的影响研究进展,以下垫面空间特征对产汇流过程的影响为主线,聚焦不透水面和微地形两类空间特征,总结城市下垫面空间特征及其表征方法;从不透水率与不透水面空间变化、数值模拟与物理实验等方面,分别梳理不透水面和微地形等空间特征对地表产汇流过程的影响研究成果。展望未来城市下垫面空间特征对地表产汇流过程的影响研究重点和发展方向,主要包括影响机理解析、主控空间特征参数识别与敏感性分析、城市水文效应适应性应对等,以期为快速城市化下城市水文效应解析和城市洪涝灾害防治提供一定参考。  相似文献   

2.
遵义市岩溶地下水环境的空间信息统计组合分析   总被引:1,自引:0,他引:1  
叶永青  王中美 《地下水》2012,(3):143-146,183
应用空间信息统计分析理论与方法来分析遵义市岩溶地下水环境,对遵义市城区岩溶地下水中的硫酸盐(SO42-)、氨氮(NH4+)、亚硝酸盐(NO2-)、硝酸盐(NO3-)等离子作克里格(Kriging)估值等值线图,并根据等值线图对4种离子的空间分布特征及范围、空间变化规律进行分析评价。  相似文献   

3.
There are few inter-African country urban analyses because of the continent’s enormous size and socioeconomic diversity, language barriers, and wide variations in national and regional urban research capacity. Nevertheless, comparative urban studies are critical in understanding contemporary African urbanization. In this comparative spatial and temporal analysis of Ghana and Kenya’s urbanization, we find that both countries are urbanizing rapidly and are faced with many common urban problems. Moreover, Ghana is more urbanized than Kenya and has a larger indigenous urban imprint and a more widely dispersed urban pattern. Besides their physiographic and population conditions, we trace these countries’ convergent and divergent urban trends to their shared but unique experiences of colonialism, nationalism and globalization.  相似文献   

4.
银川平原地城镇区域水资源空间分布与城镇形成   总被引:1,自引:0,他引:1  
胡嘉  段汉明 《地下水》2011,33(2):173-175,178
从银川平原城镇区域水资源的分析入手,采用分形理论结合GIS软件空间分析技术,对银川平原水资源的空间分布进行定量化的分析,得出银川平原城镇区域的水资源呈现出集中分布的特征形态.并以此形态特征为基础对其与银川平原城镇的空间的分布的关系进行分析.认为银川平原城镇区域范围内的水资源空间分布以集中性的特点,影响着城镇的工农业生产...  相似文献   

5.
景观生态学在城市规划和管理中的应用   总被引:53,自引:2,他引:53  
城市是典型的人工景观,空间结构上属于紧密汇聚型,功能上表现为高能流、高容量和文化上的多样性。城市景观生态研究包括城市空间结构与生态过程,城市景观风貌与城市生态建设,城市景观规划是其最直接的应用。首先论述了城市景观质量与价值评价,包括景观美学评价与景观视觉容量。城市空间结构和景观规划原则是该文论述的主题,包括城市空间布局、城市空间扩展的廊道效应以及城市绿地系统的空间结构分析;以上海和广州市的绿地系统为例进行了重点介绍,最后对于城乡交错带的景观变化进行分析,用景观格局及其动态来描述城乡交错带的城市化过程特点,介绍了上海和沈阳的典型研究。  相似文献   

6.

Over-exploitation of groundwater in many evolving urban settings causes ground subsidence and permanent loss of aquifer storage capacity. DInSAR (differential interferometric synthetic aperture radar) time series data from 2016 to 2019 were used to monitor and model the surface deformation around Nairobi, Kenya, where the water demand has exceeded the supply without capacity augmentation for over two decades. The aquifer system constitutes hard rock to semiconfined ash beds in volcanic terrain. The Small Baseline DInSAR technique identified the spatial pattern of subsidence and magnitude (line-of-sight (LOS) velocity), which exceeds 41 mm/year in the semiconfined aquifer towards the western-central part of Nairobi. The spatial distribution of subsidence is consistent with the groundwater level drop and probable compaction modeled using aquifer characteristics for 1950–2015. The Global Navigation Satellite System (GNSS) data at a station from 2007 to 2018 indicate a cumulative 4-cm subsidence which is comparable to ~2.5-cm LOS subsidence from the present study for 2016–2019. The correlation with other hydrological data suggests the aquifer is experiencing inelastic subsidence due to unsustainable groundwater extraction, putting a massive strain on Nairobi’s aquifer system. The present DInSAR based study establishes its effectiveness in the monitoring of groundwater over-exploitation-based subsidence and associated hazard to the aquifer in emerging urban centers.

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7.
The purpose of the study reported here is to assess whether it may in some circumstances be useful and appropriate to use a parent material (PM) soil chemistry mapping method developed for national soil chemistry data to portray spatial variation in urban soil chemistry data in Great Britain. Analysis of variance (ANOVA) of the urban soil data suggests that spatial interpolation of soil ambient background concentrations (ABCs) using PM classified soil data may be justified for those elements with strong geogenic control. The PM soil chemistry mapping method for urban soil data is demonstrated using data from the Northampton urban area, in the English Midlands. Geometric mean (GM) and inverse distance weighting (IDW) interpolations based on the nearest four topsoil samples were evaluated. Independent validation indicated that for As, Cr, Fe and to a lesser extent K, which all exhibit relatively strong geogenic control in the Northampton urban area: (i) the PM soil chemistry mapping method is more accurate and effective than the conventional IDW grid mapping and (ii) PM soil chemistry mapping based on the average of the nearest four Lne element concentrations is more accurate than mapping based on IDW values calculated from the nearest four Lne element concentrations. The variation in effectiveness of the methods can be explained by the fact that PM exerts a significant control on As, Cr, Fe and K in the Northampton area whereas anthropogenic inputs appear to be the dominant control on the spatial variation of Pb, especially at high concentrations. The PM mapping method would be expected to work efficiently in other urban areas and for those elements where a significant proportion of the variation can be explained by PM.  相似文献   

8.
基于饱和渗透系数空间变异结构的斜坡渗流及失稳特征   总被引:1,自引:0,他引:1  
以往研究一般采用单随机变量方法(SRV)或基于水平或垂直方向波动范围生成的空间变异随机场来模拟岩土参数的空间变异性,对具有倾斜定向特征的空间变异随机场未有涉及.基于条件模拟相关理论和非侵入式随机有限元的理论框架,提出了利用序贯高斯模拟方法进行斜坡参数条件随机场模拟并运用有限元方法进行斜坡渗流和稳定性分析的方法.针对理想边坡,对各向同性和几何各向异性的共7种空间变异结构的饱和渗透系数(Ks)各进行了200次条件随机场模拟,基于条件随机场模拟结果进行了有限元渗流和稳定性计算,对每种空间变异结构多次计算结果进行了统计分析.结果表明:本文所提出的方法不仅再现了研究区域参数的空间二阶统计特性,通过设定变异函数参数进行不同空间变异类型、变异程度、变异定向性的随机场模拟,同时利用现场观测数据对随机场模拟结果进行条件限制,从而提高了随机场的赋值精度;Ks的空间变异结构对孔隙水压力的分布规律、地下水位线变化范围、稳定性系数和最危险滑动面分布特征均有一定程度的影响.本研究为库岸斜坡稳定性评价提供方法支撑.   相似文献   

9.
10.
徐画  陈建平 《江苏地质》2020,44(4):415-421
为揭示大连城市用地扩张的空间分布特征,基于DSMP/OLS夜间灯光数据提取1998—2013年大连地域边界,并得到各地区的灯光阈值及地域边界分区统计面积。通过计算不同时期不同区域的城市用地增长景观格局指数,研究该市16年来的城市用地扩张方向、强度和空间景观格局变化,以揭示大连20年来城市用地扩张的空间分布特征。结果表明,城市用地扩张主要集中在沙河口区、中山区和西岗区,并以其为中心向甘井子区、旅顺口区、金州区等区域扩张。城市用地空间格局总体基本稳定,受地理条件、空间距离、经济发展和政策指引等因素的影响,城市用地扩张在不同方向上差异化显著。研究成果可作为大连城市规划的依据。  相似文献   

11.
This paper discusses how GIS (Geographic Information System) can contribute to the research field of urban analysis. The purpose of urban analysis is to explain the processes of spatial distributions in urban areas. For this purpose, urban analysts often need to manipulate large amounts of spatial data. This is the reason why urban analysis cannot advance without GIS. Analysts can visualize urban affairs using GIS and find the processes of spatial distributions. For example, in this paper, land use distributions in Nagoya City, Japan are visually analyzed with ArcView GIS. This analysis demonstrates that GIS can contribute to urban analysis. After this analysis, future work is discussed based on the reviews of recent studies on urban analysis using GIS. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

12.
Variations of the Effective Temperature Index (ET) in Kenya   总被引:2,自引:0,他引:2  
Using the Effective Temperature Index (ET) as a measure of climatic comfort conditions in Kenya, this study analyses its spatial, seasonal and diurnal variations. This index is computed using data collected from 57 weather stations spread throughout the country. Isarithmic mapping technique and the conditioning square method are used in this analysis. The results indicate that there exists in Kenya marked spatial, seasonal and diurnal variations of climatic comfort conditions. A classification of the country using this index and the Terjung (1968) system of climatic classification yields six climatic comfort zones. This type of physio-climatic studies has significant implications for Kenya in aspects such as building, clothing, recreation and sporting. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

13.
中国地级及以上城市紧凑度的综合测度及其空间关联分析   总被引:2,自引:0,他引:2  
潘竟虎  文岩 《冰川冻土》2013,35(1):233-239
从经济紧凑度、 土地利用紧凑度、 人口紧凑度和基础设施紧凑度等方面, 构建城市紧凑度的综合测度模型. 运用主成分分析法, 对2009年中国287个地级及以上城市紧凑度及其空间溢出效应进行综合测度. 结果表明: 紧凑度大致以"塔河-凭祥"一线为界, 以东区域的城市紧凑度水平较高, 以西的地区城市紧凑度水平低. 紧凑度Moran's I高值区连片集中在珠三角和长三角两个区域, 中心城市紧凑度的带动性和辐射性较强. 紧凑度呈现明显的热点-次热点-次冷点-冷点自东向西带状分布的格局. 经济发展、 土地利用结构和人口密度是目前中国地级以上城市紧凑度的重要决定因素, 城市土地利用因子表现相对较均衡, 而经济发展和人口密度两个主因子则表现出较强的不均衡性.  相似文献   

14.
河西地区城镇体系特征及未来发展构想   总被引:8,自引:0,他引:8  
张志斌  张小平 《冰川冻土》2002,24(4):463-469
河西地区城镇体系在空间地域结构上,表现出绿洲城镇的特点;在职能类型结构上,以综合性城镇为主;在规模等级结构上,具有经济不发达地区城镇体系的共性. 未来城镇体系建设,必须从区域整体发展的宏观思路出发,统一构建与绿洲环境相协调的城镇体系格局,使水资源能够支持重点城镇的发展,围绕酒泉市、张掖市、武威市和敦煌市4个区域中心城市,有意识地利用"点-轴"结构,积极培育次级中心,形成空间分布合理、职能类型多样、规模等级协调的城镇体系网络,促进河西地区社会经济的持续发展.  相似文献   

15.
Olga I. Vendina 《GeoJournal》1997,42(4):349-363
Major trends of social restructuring of Moscow population and processes of intra-urban segregation are discussed. The article comprises two main parts. The first part deals with differences between the population of Moscow and that of Russia based on the main socio-economic indicators. In the second part, emphasis is placed on the urban processes of social stratification of the population on the basis of analysis of the demographic and employment patterns of the population and peculiarities of the functioning housing market. The merging of top government officials and new business elites is stressed. A conclusion is drawn about the variation of the character of urban population differentiation and its transition to a stage of property-based spatial segregation.  相似文献   

16.
根据研究区内地质环境特征,选取地貌类型、地面坡度、地下水位埋深、地下水腐蚀性、地基承载力、土体压缩模量和地质灾害易发性7个评价指标,利用层次分析法(AHP)和GIS空间分析对主城区建设用地适宜性进行了评价分析.结果表明,牡丹江市主城区建设用地适宜性良好,适宜区和较适宜区占主城区总面积的58.2%,并以主城区南部区域地质...  相似文献   

17.
This paper deals with slope reliability analysis incorporating two-dimensional spatial variation. Two methods, namely the method of autocorrelated slices and the method of interpolated autocorrelations, are proposed for this purpose. Investigations are carried out based on the limit equilibrium method of slices. First-order-reliability-method (FORM) is coupled with deterministic slope stability analysis using the constrained optimization approach. Systematic search for the probabilistic critical slip surface has been carried out in this study. It is shown that both methods work well in modeling 2-D spatial variation. The results of slope reliability analysis are validated by Monte Carlo simulations. Failure probabilities obtained by FORM agree well with simulation results. It is found that 2-D spatial variation significantly influences the reliability analysis, and that the reliability index is more sensitive to vertical autocorrelation distance than to horizontal autocorrelation distance. Based on this study, failure probability is found significantly overestimated when spatial variation is ignored. Finally, the possible use of the method of interpolated autocorrelations in a probabilistic finite element analysis is suggested.  相似文献   

18.
 A thorough understanding of the characteristics of transmissivity makes groundwater deterministic models more accurate. These transmissivity data characteristics occasionally possess a complicated spatial variation over an investigated site. This study presents both geostatistical estimation and conditional simulation methods to generate spatial transmissivity maps. The measured transmissivity data from the Dulliu area in Yun-Lin county, Taiwan, is used as the case study. The spatial transmissivity maps are simulated by using sequential Gaussian simulation (SGS), and estimated by using natural log ordinary kriging and ordinary kriging. Estimation and simulation results indicate that SGS can reproduce the spatial structure of the investigated data. Furthermore, displaying a low spatial variability does not allow the ordinary kriging and natural log kriging estimates to fit the spatial structure and small-scale variation for the investigated data. The maps of kriging estimates are smoother than those of other simulations. A SGS with multiple realizations has significant advantages over ordinary kriging and even natural log kriging techniques at a site with a high variation in investigated data. These results are displayed in geographic information systems (GIS) as basic information for further groundwater study. Received: 27 August 1999 · Accepted: 22 February 2000  相似文献   

19.
基于普适性单通道算法,利用2005年5月6日的TM数据反演北京市区的实际地表温度。在此基础上,分析了北京市区的热环境特征、热岛分布的位置。运用GIS空间分析工具,分析了地表温度与地形特征和地表覆盖类型之间的关系。结果表明,北京市热岛分布具有环状和带状分布特征,高程较低处和坡度较小处更容易形成热岛中心,不同地表覆盖类型的热特征具有显著的差异。  相似文献   

20.
城市地表径流-灰尘-污染物输移研究进展   总被引:1,自引:0,他引:1       下载免费PDF全文
城市地表"径流-灰尘-污染物"作为一个三相介质系统,相互作用机理十分复杂。分别从城市地表灰尘颗粒对不同种类污染物的吸附效应及时空分布规律、地表(坡面)降雨径流特性及过程模拟、地表径流-灰尘-污染物协同输移与削减等方面,总结与分析了现有的研究进展。从本质上来看,城市地表灰尘可视为由不同粒径泥沙颗粒组成的综合体,有必要基于泥沙运动力学理论加强对地表径流中灰尘颗粒运动规律的研究,并以灰尘颗粒对不同污染物的吸附、沉淀作用为纽带,探讨"径流-灰尘-污染物"的协同输移与削减机制。其中,如何有效扩展城市调查样本容量,比较研究不同下垫面径流动力特性,并从径流能量或功率角度出发,研究不同粒径灰尘颗粒的分组起动与输移规律,并建立在径流输送过程中的挟沙力方程,将是今后需要深入研究的问题。  相似文献   

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