Direction Of Urban Expansion Research Articles

Detecting China’s Urban Expansion Over the Past Three Decades Using Nighttime Light Data

China has experienced a rapid urban expansion over the past three decades because of its accelerated economic growth. In this study, we detected and analyzed the urban expansion of China during this period using multi-temporal Defense Meteorological Satellite Program Operational Linescan System (DMSP-OLS) nighttime light data and multi-source Normalized Difference Vegetation Index (NDVI) data. First, an intercalibration was performed to improve the continuity and comparability of the nighttime light data from 1992 to 2010. The nighttime light and NDVI data were then subjected to a local support vector machine (SVM) based region-growing method to extract the urban areas from 1992 to 2010. The urban areas from 1981 to 1991 were identified using the areas in 1992 and NDVI data, based on the hypothesis that China’s urban expansion continued during this period. Finally, the extracted time-series urban maps were validated with Landsat images. The proposed local SVM-based region-growing method performed better than a local thresholding method and a global SVM-based region-growing method according to visual and quantitative comparisons of the urban boundaries and areas. We also analyzed the expansion rates to understand the dynamics of the urban areas in China and in its seven economic regions. In particular, the urban expansion patterns were investigated in three typical urban agglomerations, i.e., Beijing–Tianjin–Hebei, Yangtze River Delta, and Pearl River Delta. The proposed urban expansion direction, urban expansion intensity, and relative ratio of urban expansion demonstrated the regional variation among the three urban agglomerations.

Quantitative analysis of urban sprawl in Tripoli using Pearson's Chi-Square statistics and urban expansion intensity index

Urban expansion is a spatial phenomenon that reflects the increased level of importance of metropolises. The remotely sensed data and GIS have been widely used to study and analyze the process of urban expansions and their patterns. The capital of Libya (Tripoli) was selected to perform this study and to examine its urban growth patterns. Four satellite imageries of the study area in different dates (1984, 1996, 2002 and 2010) were used to conduct this research. The main goal of this work is identification and analyzes the urban sprawl of Tripoli metropolitan area. Urban expansion intensity index (UEII) and degree of freedom test were used to analyze and assess urban expansions in the area of study. The results show that Tripoli has sprawled urban expansion patterns; high urban expansion intensity index; and its urban development had high degree of freedom according to its urban expansion history during the time period (1984-2010). However, the novel proposed hypothesis used for zones division resulted in very good insight understanding of urban expansion direction and the effect of the distance from central business of district (CBD).

基于增强回归树和Logistic回归的城市扩展驱动力分析

PDF HTML阅读 XML下载 导出引用 引用提醒 基于增强回归树和Logistic回归的城市扩展驱动力分析 DOI: 10.5846/stxb201212121790 作者: 作者单位: 中科院沈阳应用生态研究所，森林与土壤生态国家重点实验室,中科院沈阳应用生态研究所，森林与土壤生态国家重点实验室,中科院沈阳应用生态研究所,中科院沈阳应用生态研究所，森林与土壤生态国家重点实验室,中科院沈阳应用生态研究所，森林与土壤生态国家重点实验室 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金资助项目（41171155）；国家科技支撑计划课题资助项目（2012BAJ15B06） Driving forces analysis of urban expansion based on boosted regression trees and Logistic regression Author: Affiliation: State Key Laboratory of Forest and Soil Ecology, Institute of Applied Ecology, Chinese Academy of Sciences,State Key Laboratory of Forest and Soil Ecology, Institute of Applied Ecology, Chinese Academy of Sciences,Chinese Academy of Sciences, Shenyang Liaoning,,, Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:研究城市扩展驱动力对于准确判断城市发展规律，剖析演化过程和预测城市未来扩展趋势具有重要意义，同时也能为制定合理的调控政策提供指导。以沈阳市1997-2010年城市建成区变化作为因变量，选取三大类10种驱动因子，利用增强回归树（BRT）和Logistic回归两种方法分析影响城市扩展的主要驱动力。结果表明：（1）BRT分析得到影响沈阳城市扩展的驱动因子从大到小依次是：距1997年城区距离、距河流距离、数字高程模型DEM、距高速公路和铁路距离、土地利用类型、开发区规划、GDP、人口密度、坡向和坡度；（2）Logistic回归分析得到影响沈阳城市扩展的前8位驱动因子依次是：开发区、距1997年城区距离、DEM、距高速公路和铁路距离、人口密度、距河流距离、农村居民点和坡度；（3）距1997年城区距离、DEM、距高速公路和铁路距离是影响沈阳城市扩展的主要驱动力，均位于主要因子的前四位；（4）总体来说，沈阳城市扩展受邻域因子影响最大，而自然因子的影响相对较小，社会经济因子则只有开发区和农村居民点对城市扩展影响较大。 Abstract:The rapid relentless urban area expansion has led to a series of problems in China. Many researches focused on this issue in recent years. Driving forces are the core topic in urban expansion,as well as the basic component of modeling and predicting. It is very useful and meaningful to analyze the driving force of urban expansion, which may provide us with a scientific basis to rationally utilize land resources, determining the law of urban development, researching the evolution process, predicting the urban expansion trends, and also providing guidance for the development of rational control policies.The Shenyang city was chosen as study area. Eight categories of land use types were extracted from remote sensing images (1997 and 2010) with ArcGIS software. Ten driving forces were chosen, including three natural factors, three distance factors, four social and economic factors. which were calculated based on the land use maps, DEM, topographic maps, zoning maps and the statistical yearbooks. The dependent variable was the change of built-up area of Shenyang from 1997 to 2010. Boosted regression trees (BRT) is an ensemble method and is a combination of techniques between statistical and machine learning traditions that has shown to be effective to identify relationships between results and influencing factors. Logistic regression is a method to discover the empirical relationships between a binary dependent and several independent categorical and continuous variables. Boosted Regression Trees and Logistic regression were used to analyze the main driving force of urban expansion synthetically.The result illustrated the relative influence of driving factors was followed by distance from urban area of 1997, distance from river, DEM, distance from highway and railway, land use types, development plan, GDP, population density, aspect, and slope based on BRT analysis. According to Logistic regression analysis, the relative influence of important factors was followed by development zone, distance from urban land of 1997, DEM, distance from highway and railway, population density, distance from river, rural residential areas and slope. The most important driving forces affecting the expansion of Shenyang are distance from urban area of 1997, DEM, distance from highway and railway. Meanwhile, they were all located in the top four of the main factors. The results revealed that the distance factors were the most important factors, and the total contribution rate of relative influence was up to 61.4%. It is demonstrated distance factors are the main driving forces of urban expansion. Natural factorswere less important, but the relative influence of DEM was important, and the contribution rate was 12.5%. Development zones and rural settlements are the only two factors have much influence in the socio-economic factors.On the whole, location factors, which refer to the distance from urban land in this study, were the leading factors of urban expansion. Natural factors, such as DEM, rivers and so on, are the basis of urban development, determining the overall urban spatial form. The construction of infrastructures, such as roads and railways, are the frame of the city. The social and economic factors decided the speed of urban expansion. Urban planning and development zone construction provided the direction of urban expansion. 参考文献 相似文献 引证文献

Suzhou Urban Expansion and its Fractal Characteristic Analysis

The Suzhou urban expansion as the research object, used the 1987,2000,2005 and2009 Landsat TM / ETM+ multi-objective remote sensing images to acquire the Suzhou urban landscape map, from the urban expansion speed, urban expansion strength, urban expansion elasticity coefficient, and the urban expansion direction to analyze the urban expansion dynamic changes, and then used the fractal model to calculate the Suzhou construction land fractal dimension and stability indexes in 1987-2009, and explored the relationship between the urban construction complexity and stability and the fractal dimension. The results show that, with the urbanization process accelerated, the construction land area in Suzhou City continued to increase, the urban expansion strength further enhanced, the urban expansion speed further accelerated, the city development direction mainly toward the north and south, southeast and northwest. The 1987-2009 urban construction land fractal dimension showed increasing -- reducing -- increasing trend, the urban construction land shape become more and more irregular, the urban construction land complexity increased, the urban construction land plaque stability decreased gradually.

Spatial Diffusion Model Analysis and Trend of Shizuishan City

The urban expansion direction and mode of Shizuishan City is addressed based on GIS and improved spatial diffusion model-replacing the spatial straight distance with cost weighted distance. This paper divides its spatial expansion into four cases: zero resistance, resistance, incomplete barrier and isolation. The diffusion model of urban space in terms of the new understanding of the resistance barrier in the spatial diffusion process is discussed. Then, this paper puts forward new trends of spatial development. The results reveal that Dawukou city area and Pingluo city, and Wuhai city and Huinong district form the coordination development tendency.

Monitoring urban expansion and land use/land cover changes of Shanghai metropolitan area during the transitional economy (1979–2009) in China

This study explored the spatio-temporal dynamics and evolution of land use/cover changes and urban expansion in Shanghai metropolitan area, China, during the transitional economy period (1979-2009) using multi-temporal satellite images and geographic information systems (GIS). A maximum likelihood supervised classification algorithm was employed to extract information from four landsat images, with the post-classification change detection technique and GIS-based spatial analysis methods used to detect land-use and land-cover (LULC) changes. The overall Kappa indices of land use/cover change maps ranged from 0.79 to 0.89. Results indicated that urbanization has accelerated at an unprecedented scale and rate during the study period, leading to a considerable reduction in the area of farmland and green land. Findings further revealed that water bodies and bare land increased, obviously due to large-scale coastal development after 2000. The direction of urban expansion was along a north-south axis from 1979 to 2000, but after 2000 this growth changed to spread from both the existing urban area and along transport routes in all directions. Urban expansion and subsequent LULC changes in Shanghai have largely been driven by policy reform, population growth, and economic development. Rapid urban expansion through clearing of vegetation has led to a wide range of eco-environmental degradation.

Expansion of Ürümqi urban area and its spatial differentiation

The expanded area and structure of urban lands and landscape features in Urumqi City are analyzed using RS and GIS means based on the MSS image in 1975 and the TM images in 1990, 1999 and 2002, as well as other related maps. On which the scale, intensity and spatial differentiation of the expansion of the Urumqi urban area during different periods are lucubrated. The results reveal that urban expansion was rapid during the periods of 1949–1965 and 1975–1990, and that it was stable after the 1990s. The urban expansion pattern was significantly different during different time periods: the urban area was expanded outwards based on old districts in a spanned development pattern during the period of 1949–1965; development was stagnant during the period of 1965–1975; urban expansion developed mainly in old districts in a grouped way during the period of 1975–1990. The trend of urban expansion along the traffic lines was obvious, and the direction of urban expansion was dominated by the south-north zonal expansion and supplemented by east-west axial expansion; urban expansion reached the development stage of “multiple centers and multiple districts” after the 1990s, and urban networks were developed more precisely after this time. The sources for urban expansion were mainly cultivated lands, grasslands and unused lands; during urban expansion, the land area devoted to traffic lines, residential areas, dispersive industrial and mineral areas, and garden plots was rapidly enlarged.

Municipal Markets in New Orleans

Municipal markets in American cities were created to centralize the sale of meat and produce for the purpose of protecting the consumer from high prices and food of poor quality. Large cities generally operated several markets, with New Orleans having the most extensive market system. In New Orleans the pattern of market locations followed the direction of urban expansion and their location, in turn, influenced the origin and growth of neighborhood shopping districts. The decline of municipal markets began in the 1920s. Increased competition by chain stores, the improved mobility of urban dwellers and municipal market mismanagement were the principal forces influencing their decline. The revival of old marketplaces in some cities is injecting new vitality into inner city neighborhoods. In New Orleans and many other cities, however, municipal market structures represent cultural relics woven discretely into the urban fabric; today they stand as historical monuments to urban-cultural geography.