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1.
Shrinking New Orleans: Post-Katrina Population Adjustments 总被引：1，自引：0，他引：1
《Urban geography》2013,34(5):675-699
The flooding caused by hurricane Katrina in 2005 acted as a catalyst for an abrupt change of the demographic landscape of the New Orleans metropolitan area. New Orleans city proper has been a shrinking city for the last half century, but its population loss was balanced by expanding suburbs until 2005. Based on a comparison of the newly released 2010 census data with the 2000 data, this paper discusses the major population adjustments that have resulted from the disaster. Hurricane Katrina has caused the entire metropolitan area to shrink much faster than previous declines. Five years after the storm, New Orleans displays some limited signs of resilience, although the storm seems to have accelerated its population decline. Furthermore, a close examination of the available data shows us that Katrina has provoked a major change in the city's ethnic landscape. 相似文献
2.
Urbanization and the ability to manage for a sustainable future present numerous challenges for geographers and planners in metropolitan regions. Remotely sensed data are inherently suited to provide information on urban land cover characteristics, and their change over time, at various spatial and temporal scales. Data models for establishing the range of urban land cover types and their biophysical composition (vegetation, soil, and impervious surfaces) are integrated to provide a hierarchical approach to classifying land cover within urban environments. These data also provide an essential component for current simulation models of urban growth patterns, as both calibration and validation data. The first stages of the approach have been applied to examine urban growth between 1988 and 1995 for a rapidly developing area in southeast Queensland, Australia. Landsat Thematic Mapper image data provided accurate (83% adjusted overall accuracy) classification of broad land cover types and their change over time. The combination of commonly available remotely sensed data, image processing methods, and emerging urban growth models highlights an important application for current and next generation moderate spatial resolution image data in studies of urban environments. 相似文献
3.
《The Professional geographer》2013,65(3):371-386
Urbanization and the ability to manage for a sustainable future present numerous challenges for geographers and planners in metropolitan regions. Remotely sensed data are inherently suited to provide information on urban land cover characteristics, and their change over time, at various spatial and temporal scales. Data models for establishing the range of urban land cover types and their biophysical composition (vegetation, soil, and impervious surfaces) are integrated to provide a hierarchical approach to classifying land cover within urban environments. These data also provide an essential component for current simulation models of urban growth patterns, as both calibration and validation data. The first stages of the approach have been applied to examine urban growth between 1988 and 1995 for a rapidly developing area in southeast Queensland, Australia. Landsat Thematic Mapper image data provided accurate (83% adjusted overall accuracy) classification of broad land cover types and their change over time. The combination of commonly available remotely sensed data, image processing methods, and emerging urban growth models highlights an important application for current and next generation moderate spatial resolution image data in studies of urban environments. 相似文献
4.
大都市区化是全球城市化进程中的普遍现象,研究大都市区域城市扩张进程对理解其未来增长趋势、区域可持续发展具有重要意义。大都市区土地扩张及区域间的对比分析,以及都市区发育过程中城市扩张的一般化空间模式还未被深入理解。论文选取东京、纽约和上海3个大都市区,获取1990—2015年间3期Landsat影像数据,使用梯度和格网分析法,采用城市土地密度函数和城市扩张指数,从建设用地数量变化及其时空分布、城市形态变化等方面,多角度对比分析各城市不同阶段建设用地增长的时空差异。结果表明：① 大都市区边界仍在不断扩展,建设用地在研究期内持续增长;20多年间东京、纽约和上海的建设用地面积分别增长了63%、53%和233%;上海一直处于高强度扩张状态,而纽约的城市扩张在后期几近停滞。② 大都市区建设用地密度从中心向外呈圈层递减式分布,城市核心区和边缘区半径的增长最明显;城市形态均趋向于紧凑。③ 新增建设用地时空异质性明显。东京的远郊新城不断建设,纽约一些尚有发展潜力的区域次中心仍在扩张但速率逐渐放缓,上海的核心区外围增长剧烈并逐渐向远城区推进。④ 大都市区域扩张先后经历高速期—缓慢期—停滞期,扩张进程表现为核心区膨胀—次中心及新城建设—逐步形成稳定的多中心结构。 相似文献
5.
Kenan Li Nina S. N. Lam 《International journal of geographical information science》2018,32(4):685-710
This study developed a spatial dynamic model to examine the coupled natural–human responses in the form of changes in population and associated developed land area in the Lower Mississippi River Basin region. The goal was to identify key socioeconomic factors (utility) and environmental factors (hazard damages, elevation, and subsidence rate) that affected population changes, as well as to examine how population changes affected the local utility and the local environment reciprocally. We first applied areal interpolation techniques with the volume-preserving property to transform all the data at Year 2000 into a unified 3 km by 3 km cellular space. We then built an Elastic Net model to extract 12 variables from a set of 33 for the spatial dynamic model. Afterward, we calibrated the neighborhood effects with a genetic algorithm and use the spatial dynamic model to simulate population and developed land area in 2010. Furthermore, we took a Monte Carlo approach for analyzing the uncertainty of the model outcome. Our accuracy assessment shows that the model on average slightly overpredicts the number of population and the developed land percentage at 2010, as indicated by the low values of mean absolute deviation (MAD) due to quantity. On the other hand, the MADs due to allocation are larger than the MADs due to quantity, with most outliers found in the New Orleans region where population and urban development declined significantly during 2000–2010 after Hurricane Katrina. The proposed model sheds light on the complex relationships between coastal hazards and human responses and provides useful insights to strategic development for coastal sustainability. 相似文献
6.
Yaqian Zhai Yao Yao Xun Liang Xia Li Yongting Pan 《International journal of geographical information science》2020,34(7):1475-1499
ABSTRACT Vector-based cellular automata (VCA) models have been applied in land use change simulations at fine scales. However, the neighborhood effects of the driving factors are rarely considered in the exploration of the transition suitability of cells, leading to lower simulation accuracy. This study proposes a convolutional neural network (CNN)-VCA model that adopts the CNN to extract the high-level features of the driving factors within a neighborhood of an irregularly shaped cell and discover the relationships between multiple land use changes and driving factors at the neighborhood level. The proposed model was applied to simulate urban land use changes in Shenzhen, China. Compared with several VCA models using other machine learning methods, the proposed CNN-VCA model obtained the highest simulation accuracy (figure-of-merit = 0.361). The results indicated that the CNN-VCA model can effectively uncover the neighborhood effects of multiple driving factors on the developmental potential of land parcels and obtain more details on the morphological characteristics of land parcels. Moreover, the land use patterns of 2020 and 2025 under an ecological control strategy were simulated to provide decision support for urban planning. 相似文献
7.
8.
深圳市近20年城市景观格局演变及其驱动因素 总被引：1，自引：0，他引：1
基于深圳市1996—2015年土地利用数据,利用景观指数、景观转移矩阵和景观扩张指数等方法探究了深圳市近20年景观格局时空变化、主要景观类型转移和建筑用地扩张模式,最后使用Binary Logit模型考察了市级和区级建筑用地景观扩张的主要驱动因素。结果表明：① 1996—2015年,深圳市建筑用地景观优势性逐步增强,面积增加15.81%,以蔓延式（61.9%）和填充式（36.27%）扩张为主;② 1996—2006年为城市化快速扩张期,建筑用地扩张呈集中开发形态,景观多样性和均匀性增加,城市扩张中心略微向北部和东部移动,2006—2015为城市化低速过渡期,景观破碎化加剧,城市扩张重心向北部和西部偏移;③ 在市级尺度上,GDP密度和人口密度对建筑用地景观扩张有显著正影响,生态控制线、高程、坡度和至道路的距离有着显著负影响。每单位生态控制线范围、坡度的增加分别将使建筑用地景观扩张的机会比率将平均减少到原来0.8168倍、0.8841倍。各驱动因素表现出区域和尺度差异性,GDP对宝安区、南山区和坪山区,人口增长对宝安区、龙华区,以及交通可达性对大鹏新区、龙岗区驱动分别最为突出。研究结果可以为中国城市快速扩张过程中的景观格局变化提供科学实践。 相似文献
9.
Land use and land cover change in Greater Dhaka, Bangladesh: Using remote sensing to promote sustainable urbanization 总被引：12，自引：0，他引：12
This study evaluates land use/cover changes and urban expansion in Greater Dhaka, Bangladesh, between 1975 and 2003 using satellite images and socio-economic data. Spatial and temporal dynamics of land use/cover changes were quantified using three Landsat images, a supervised classification algorithm and the post-classification change detection technique in GIS. Accuracy of the Landsat-derived land use/cover maps ranged from 85 to 90%. The analysis revealed that substantial growth of built-up areas in Greater Dhaka over the study period resulted significant decrease in the area of water bodies, cultivated land, vegetation and wetlands. Urban land expansion has been largely driven by elevation, population growth and economic development. Rapid urban expansion through infilling of low-lying areas and clearing of vegetation resulted in a wide range of environmental impacts, including habitat quality. As reliable and current data are lacking for Bangladesh, the land use maps produced in this study will contribute to both the development of sustainable urban land use planning decisions and also for forecasting possible future changes in growth patterns. 相似文献
10.
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
11.
南京大都市区建设用地扩张特征与机理 总被引：6，自引：2，他引：4
作为全球城市化最快的地区之一,中国建设用地的扩张引起了广泛的关注。以长三角北翼中心城市南京为例,利用遥感、土地利用调查等数据研究大都市区建设用地扩张的过程、格局与机理。研究表明,1985-2007年南京市在工业化、城市化和国际化的推动下经济快速增长,引致了建设用地的扩张,年均增长率为3.14%。2001年后随着城市发展模式由单中心向多中心转换,建设用地呈加速扩展趋势。南京市建设用地扩展具有明显的沿长江和南北交通走廊轴向发展的特征。开发区和新城建设是南京市建设用地扩张的主要方式。区、县尺度的回归分析表明,人口增加、全球化是城镇工矿用地扩张的重要推手;经济的服务业化有利于土地集约利用,减少对用地的需求,这种影响在城区更大;在分权化竞争中,都市区政府具有更强的控制力。 相似文献
12.
1987-2006年北方13省土地利用/覆盖变化驱动力分析 总被引：7，自引：1，他引：6
以北方13省为研究区,利用主成分分析与逐步多元回归分析方法,分析了研究区土地利用/覆盖变化的驱动机制.结果表明:(1)由于地域差异的原因,各个子区域中土地利用/覆盖类型变化的驱动因子有所不同;(2)社会经济要素是研究区土地利用/覆盖变化的主导驱动因子,尤其是人口因素发挥着重要作用;(3)气温、降水等自然因子对区域土地利用/覆盖变化也具有一定的制约作用,主要表现在东北和西北等受自然要素限制较为突出的地区.政策驱动因子在研究中没有得到反映,但不难判定国家生态环境政策无疑也对区域土地利用/覆盖的变化起到了非常重要的作用. 相似文献
13.
New Orleans has suffered from a significant population decline during 2000–2010, mainly due to Hurricane Katrina in 2005. Regression models are used here to explain the spatial variability of population change in New Orleans by variables such as proximity (distance or travel time) to the central business district (CBD), a natural environment variable “elevation”, and two composite socio‐demographic indices derived from variables in the census. The research reveals a U‐shaped population‐change profile with distance or travel time from the CBD, population loss bottomed at 4–5 kilometers (10–15 minutes) from the CBD and recovered towards both the CBD and suburbs. This suggests possible converging forces of suburbanization (that is, a nationwide trend that began long before the hurricane) and the CBD's anchoring role in the post‐Katrina recovery. Greater population loss was also observed in the socioeconomically disadvantaged and lower‐elevated areas, but neighborhoods of Hispanic concentration experienced less population loss. 相似文献
14.
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
15.
Spatiotemporal patterns of urban growth can help identify impacts of urbanization, assess conceptual models of that growth, help predict future change, and inform associated urban management policies. Using multi-temporal spatial data (1938-2014), we categorized the newly urbanized area in Treasure Valley, Idaho into four urban growth forms and six urban land use classes. A time series analysis of new development revealed the existence of decadal-scale variability of urbanization at various levels of urban land use. Alternating dominance of dispersion and compaction processes were observed at the urban patch level. A similar periodicity was observed between edge-expansion and infill in terms of growth forms, and between residential and commercial development at the land use level. Our observations also indicate that recent urban densification is occurring in the Treasure Valley, similar to some other metropolitan regions in the United States. 相似文献
16.
Xun Liang Guangliang Chen Jiye Leng Youyue Wen Guangzhao Chen 《International journal of geographical information science》2020,34(10):1930-1952
ABSTRACT Modeling urban growth in Economic development zones (EDZs) can help planners determine appropriate land policies for these regions. However, sometimes EDZs are established in remote areas outside of central cities that have no historical urban areas. Existing models are unable to simulate the emergence of urban areas without historical urban land in EDZs. In this study, a cellular automaton (CA) model based on fuzzy clustering is developed to address this issue. This model is implemented by coupling an unsupervised classification method and a modified CA model with an urban emergence mechanism based on local maxima. Through an analysis of the planning policies and existing infrastructure, the proposed model can detect the potential start zones and simulate the trajectory of urban growth independent of the historical urban land use. The method is validated in the urban emergence simulation of the Taiping Bay development zone in Dalian, China from 2013 to 2019. The proposed model is applied to future simulation in 2019–2030. The results demonstrate that the proposed model can be used to predict urban emergence and generate the possible future urban form, which will assist planners in determining the urban layout and controlling urban growth in EDZs. 相似文献
17.
Michael Leitner Michelle Barnett Joshua Kent Tom Barnett 《The Professional geographer》2013,65(2):244-261
This research assesses the impact that one natural disaster—Hurricane Katrina—and subsequent population movements have had on crime in the state of Louisiana. Using Index Crimes from the Louisiana Commission on Law Enforcement and population estimates from the U.S. Census Bureau, time series of violent and nonviolent crime rates were first analyzed using autoregressive, integrated, and moving average (ARIMA) models. Cumulative percentile maps were created next to analyze spatial trends of crime hot and cold spots in the study area. Overall, results from this research support theories that suggest that crime rates remain stable or actually decline in regions receiving evacuees from areas hardest hit by the hurricane. In the case of Orleans Parish, results are inconclusive due to unreliable crime rates for the period following Hurricane Katrina until the beginning of 2006. It is suggested that crime rates in Orleans Parish fell drastically after the storm. However, some crime types, including robbery, burglary, and larceny, returned to pre-Katrina levels and murder and aggravated assault even exceeded prestorm averages by the end of December 2007. 相似文献
18.
The urban development of Banda Aceh, Indonesia was very rapid after the tsunami in 2004, posing critical challenges in planning for its future sustainable development. Scientifically-derived information about its land change patterns and the driving factors of its rapid urbanization might provide vital information. However, the spatio–temporal patterns of its urban land use/cover (LUC) changes have not been examined. Hence, this study aims to: (1) detect and analyze the spatio–temporal changes in the urban LUC of Banda Aceh between 2005 and 2009; and (2) examine the driving factors that influence urban growth. The 2005 and 2009 LUC maps were derived from remote sensing satellite images using a supervised classification method (maximum likelihood). Both LUC maps contained four categories, namely built-up area, vegetation, water body, and wet land. The 2005 LUC map had an overall accuracy of 77.8%, while the 2009 LUC map had 89.4%. The two LUC maps were re-classed into two categories (i.e. built-up area and non built-up area) to facilitate logistic regression analysis. A total of seven variables or potential driving factors of urban growth were identified and examined, including two socio-economic factors (population density and distance to central business district) and five biophysical factors (distances to green open space, historical area, river, highway, and coastal area). The results showed that the LUC of Banda Aceh has changed drastically between 2005 and 2009, particularly its built-up area, which increased by 90.8% (1016.0 ha) at the expense of the other LUC categories. The socio-economic factors showed positive influence to the growth of the city, whereas the biophysical factors showed negative effect, except the distance to coastal areas. The importance of the findings for future landscape and urban planning for Banda Aceh is discussed. 相似文献
19.
近5年青海省植被覆盖变化的遥感监测 总被引：3，自引：2，他引：1
This paper used five years （2001-2006） time series of MODIS NDVI images with a 1-km spatial resolution to produce a land cover map of Qinghai Province in China. A classification approach for different land cover types with special emphasis on vegetation, especially on sparse vegetation, was developed which synthesized Decision Tree Classification, Supervised Classification and Unsupervised Classification. The spatial distribution and dynamic change of vegetation cover in Qinghai from 2001 to 2006 were analyzed based on the land cover classification map and five grade elevation belts derived from Qinghai DEM. The result shows that vegetation cover in Qinghai in recent five years has been some improved and the area of vegetation was increased from 370,047 km^2 in 2001 to 374,576 km^2 in 2006. Meanwhile, vegetation cover ratio was increased by 0.63%. Vegetation cover ratio in high mountain belt is the largest （67.92%） among the five grade elevation belts in Qinghai Province. The second largest vegetation cover ratio is in middle mountain belt （61.80%）. Next, in the order of the decreasing vegetation cover ratio, the remaining grades are extreme high mountain belt （38.98%）, low mountain belt （25.55%） and flat region belt （15.46%）. The area of middle density grassland in high mountain belt is the biggest （94,003 km^2）, and vegetation cover ratio of dense grassland in middle mountain belt is the highest （32.62%）, and the increased area of dense grassland in high mountain belt is the greatest （1280 km^2）. In recent five years the conversion from sparse grass to middle density grass in high mountain belt has been the largest vegetation cover variation and the converted area is 15931 km^2. 相似文献
20.
Chandra Kant Pawe 《Geografisk tidskrift / udgivet af Bestyrelsen for Det Kongelige danske geografiske selskab》2018,118(1):88-100
Unplanned urban growth, particularly in developing countries has led to changes in land use/land cover (LULC). Numerous Indian cities face problems of unplanned LULC change due to nominal or non-existent planning efforts compounded by rapid urban population growth. The Guwahati Metropolitan Area (GMA) is one such urban centre. The present study assesses the trajectories of LULC change using Landsat imageries acquired in 1976, 1989, 2002 and 2015. Natural and semi natural vegetated area and artificial and natural water bodies decreased while built-up areas, cultivated and managed areas, and natural and semi natural non-vegetated areas increased. The built-up area increased from 23.9 in 1976 to 115.1 km2 in 2015 becoming the dominant land cover class accounting for 41.8% of the total geographical area. During this period, natural and semi natural vegetated land were reduced by 88.9 km2 at an annual rate of 2.2 km2. Over the years there was an increasing trend of built-up land and cultivated and managed areas in the peripheral areas of the city while natural and semi natural vegetated land diminished. Consequently, as in many other developing countries, there is an urgent need for the governmental authorities and other stakeholders to implement effective urban planning policies. 相似文献