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1.
The paper compares ethnic change and diversity across two recent decades using common group and area definitions. Ethnic minority groups are shown to be growing rapidly at 41 per cent between 1981 and 1991 and 39 per cent between 1991 and 2001. Some groups have grown swiftly (Black Africans, Bangladeshis), while others have seen moderate expansion (Indians, Other Asians). The White population has hardly grown and the White British population has probably declined. Black and Ethnic Minority (BEM) populations remain concentrated in metropolitan areas in 2001 as in 1991 and 1981. Whereas between 1981 and 1991, BEM groups were concentrating into metropolitan areas, between 1991 and 2001 deconcentration began for most groups. The London region stands out as highly dominant, housing more than 50 per cent of BEM populations as a whole in 1991 and 2001. However, between 1991 and 2001, BEM groups grew outside their core areas. The consequence of BEM population growth and spread has been a dramatic increase in ethnic diversity in all regions. 相似文献
2.
This research explores the factors that shape the evolving geographic distribution of business headquarters (HQ) activity. We address an understudied influence on HQ geographies: metropolitan HQ changes driven by the process of small, rapidly expanding businesses growing into mature companies. This investigation focuses on the developmental paths followed by fast-growing firms (FGFs) and the geographic distinctions that can be observed in a FGF tracking study of Canada’s metropolitan regions from 1987 to 2005. Our research findings indicate that geography plays an important role in this development, as FGF tracking records throughout Canada’s metropolitan areas diverge sharply. We find that most FGFs that emerged in Vancouver and Toronto continued as ongoing businesses following their rapid growth phase, while a high proportion of FGFs based in Montréal and Calgary did not. These results contribute to a greater understanding of metropolitan economies, business development, and HQ location in Canada 相似文献
3.
The spatial structure of a region is known to affect the degree of face-to-face interaction opportunities for a city’s residents. These interaction opportunities are important building blocks in aspects of economic production. To date, though, there is scant empirical evidence linking interaction opportunities to worker locations. In this article, using a spatial measure of social interaction potential (SIP), we seek to discover whether, and by how much, opportunities for interaction differ at home and work locations for workers within different industry and occupation groups in U.S. metropolitan areas. Based on the time-geographic concept of joint accessibility, SIP is sensitive to population and employment densities, as well as travel times associated with worker commutes in a region. We compare SIP at the census tract level of geography both within and between Metropolitan Statistical Areas (MSAs) nationally and test SIP distributions by occupation and industrial categories using nonparametric Kruskal–Wallis and Dunn tests. The study finds that several categories of higher skill and creative workers live and work in higher SIP areas. These findings provide evidence in support of theories of knowledge creation that rely on spontaneous face-to-face interaction and also indicate the effect of lifestyle preferences in location choices for highly skilled and arts workers. 相似文献
4.
The economic geography of United States’ institutional investments as of December 2010 is presented. With a self-declared value of almost $13 trillion, it is the largest class of equity investors. Included are all investors who file Securities Exchange Commission (SEC) form 13f, meaning they manage at least $100 million. Analysis is undertaken at both the firm and metropolitan levels. The largest firms and targets of investment are determined. Geographic concentrations of both investors and their major stock holdings occur in a small subset (the top 10 largest metropolitan areas). The rates of returns on investments are shown to differ by metropolitan area of investment and by urban rank in the urban hierarchy. Intra-metropolitan investment provides worse rates of returns, countering suggestions of informational advantages for local investment. The network of interurban investments shows a clear hierarchical structure, with New York City being the dominant investment centre. 相似文献
5.
《Urban geography》2013,34(5):490-500
New regional growth may perpetuate social and economic inequalities caused by uneven urban development, or may reverse such trends by expanding housing options that make possible the dispersal of lower-income households among suburban areas offering better social, economic, and educational opportunities. Supply-side housing approaches can facilitate a more equitable redistribution of housing options. In this research, we examine the role of the Low-Income Housing Tax Credit (LIHTC) program in expanding the geography of opportunity in one fast-growing region—the Dallas/Fort Worth Metroplex. Findings suggest that although LIHTC developments are penetrating the suburbs, they are not expanding opportunities for these households. Just under half of LIHTC units are found in highly clustered areas characterized by high poverty rates, minority concentrations, poor educational opportunities, and rampant crime. The remaining units are dispersed in areas with moderate conditions. Suggestions are made for altering program guidelines to achieve better dispersal, income-mixing, and regionwide distribution. 相似文献
6.
Jinyao Lin 《International journal of geographical information science》2013,27(10):1721-1736
As a consequence of rapid and immoderate urbanization, simulating urban growth in metropolitan areas effectively becomes a crucial and yet difficult task. Cellular automata (CA) model is an attractive tool for understanding complex geographical phenomena. Although intercity urban flows, the key factors in metropolitan development, have already been taken into consideration in CA models, there is still room for improvement because the influences of urban flows may not necessarily follow the distance decay relationship and may change over time. A feasible solution is to define the weights of intercity urban flows. Therefore, this study presents a novel method based on weighted urban flows (CAWeightedFlow) with the support of web search engine. The relatedness measured by the co-occurrences of the cities’ names (toponyms) on massive web pages can be deemed as the weights of intercity urban flows. After applying the weights, the gravitational field model is integrated with Logistic-CA to fulfill the modeling task. This method is employed to the urban growth simulation in the Pearl River Delta, one of the most urbanized metropolitan areas in China, from 2005 to 2008. The results indicate that our method outperforms traditional methods with respect to two measures of calibration goodness-of-fit. For example, CAWeightedFlow can yield the best value of ‘figure of merit’. Moreover, the proposed method can be further used to explore various development possibilities by simply changing the weights. 相似文献
7.
Burdack J 《Erdkunde》1989,43(4):280-292
"The article analyses the population growth in rural counties of the U.S.A. for 1970-80 and 1980-86. The growth rates are examined on different levels of aggregation (individual counties, subregions and regions) and in relation to several possible determinants of growth. The main objective of the study is to examine whether the growth patterns in the eighties support the hypothesis of a turnaround in the population development of rural areas.... The results reveal a diversity of growth patterns and significant regional differences. Rural counties within the daily urban system of a metropolitan area have significantly higher growth rates than peripheral rural counties. The results do not support the notion of a turnaround of long established trends. The trends in the eighties bear more resemblance to traditional growth patterns of rural areas." (SUMMARY IN ENG) 相似文献
8.
CHANGING SPATIAL CHARACTERISTICS OF WILLAMETTE VALLEY FARMS 总被引：2，自引：0，他引：2
This article reflects on the racial configuration of urban space. Previous research tends to posit racial segregation and diversity as either endpoints on a continuum of racial dominance or mirror images of one another. We argue that segregation and diversity must be jointly understood; they are necessarily related, although not inevitably as binary opposites. Our view is that the neighborhood geographies of U.S. metropolitan areas are simultaneously and increasingly marked by both racial segregation and racial diversity. We offer an approach that classifies neighborhoods based jointly on their compositional diversity and their racial dominance, illustrated by an examination of the neighborhood racial structure of several large metropolitan areas for 1990 and 2000. Compositional diversity increased in all metropolitan areas in ways rendered visible by our approach, including a sharp reduction in the number of highly segregated white neighborhoods, transitioning mostly into moderately diverse yet still white-dominated neighborhoods, and a fourfold increase in the number of highly diverse neighborhoods. Even so, many highly segregated spaces remain, especially for whites and blacks. Latino-dominated spaces show a mix of persistence and emergence. Although compositional diversity is increasing, highly diverse neighborhoods are still rare and are the least persistent of all racial configurations. Our approach clearly demonstrates the “both/and”-ness of segregation and diversity. 相似文献
9.
In this article, we use local indicators of spatial association (LISA) and other spatial analysis techniques to analyze the distribution of centers with high employment density within metropolitan areas. We examine the 359 metropolitan areas across the United States at three points in time (1990, 2000, and 2010) to provide a spatio-temporal panoramic of urban spatial structure. Our analysis highlights three key findings. (1) The monocentric structure persists in a majority of metropolitan areas: 56.5% in 1990, 64.1% in 2000, and 57.7% in 2010. (2) The pattern of employment centers remains stable for most metropolitan areas: the number of centers remained the same for 74.9% of metropolitan areas between 1990 and 2000 and for 85.2% between 2000 and 2010. (3) Compared with monocentric metropolitan areas, polycentric metros are larger and more dense, with higher per-capita incomes and lower poverty rates. 相似文献
10.
The suburbanization of poverty? An alternative perspective 总被引：2，自引：1，他引：1
A popular and powerful narrative focuses on a crisis of suburban decline in the United States. However, a consensus regarding the scope and scale of one dimension of suburban decline—poverty—is hindered by the use of contradictory definitions of suburban space. This research presents an alternative approach to measuring suburban poverty that is less computationally intensive yet capable of capturing complex shifts in the spatial distribution of poverty within metropolitan areas. An analysis of the distribution of poverty in the largest 100 metropolitan areas between 1990 and 2007–11 concludes that while poverty is increasing in the low-density suburbs of a handful of large metropolitan areas, the more general trend in most other metropolitan areas is an increase in poverty in moderately dense residential areas. Implicated in these trends are long-term trends in metropolitan area economic growth, a secular decline in inner-ring suburbs, and the impact of gentrification on housing opportunities for at-risk populations in large cities. 相似文献
11.
2010年4月24日民勤出现黑风天气,给当地经济和社会造成严重影响。利用民勤黑风发生前后2010年4月24日08时~25日08时的探空观测资料,对大气不稳定能量、热力参数“V—3θ”和动力参数“相对风暴水平螺旋度”进行了计算分析。结果表明：黑风发生时,民勤近地面存在正不稳定能量,促使黑风在近地面层爆发性发展,使沙尘粒子在正不稳定能量区聚积,形成黑风墙。民勤黑风爆发前和爆发时大气温湿结构呈现出上湿下干的分布特征,低层湿度较小不利于降水产生,为沙尘扬起提供了较好的垂直方向的环境场条件;黑风爆发前大气层结500 hPa以下风场的垂直分布形成顺时针滚流,为对流性不稳定层结,气层有利于黑风生成和发展;黑风过境后,风场的垂直分布顺时针滚流下降至700 hPa以下,说明大气层结的对流不稳定层结变薄、减弱,700～500 hPa存在逆时针滚流,抑制上升运动,预示黑风将减弱。黑风爆发期间在河西走廊中部存在一个相对风暴水平螺旋度负值中心,中心值达到-870 m2 /s2,远小于强沙尘暴发生的临界值-600 m2 /s2,沙尘暴的强度与相对风暴水平螺旋度负值中心存在很好的对应关系。当民勤测站的相对风暴水平螺旋度＜0,其上游存在≤-600 m2 /s2的最小中心时,民勤测站将出现强沙尘暴;当民勤测站的螺旋度＜0,其上游存在正值中心时,下游存在负值中心时,民勤测站的沙尘暴结束,能见度好转。 相似文献
12.
This study analyzes metropolitan dynamics in a small country with an “island state” context of closed boundaries, using commuting data and mobile phone tracking data. We examine whether the Israeli context encourages the formation of a monocentric “metropolitan state,” characterized by increasing links between localities throughout the country and its principal metropolitan node (Tel Aviv)—rather than with secondary metropolitan areas—and by fuzzy, overlapping metropolitan boundaries. Commuting data from the 1995 and 2008 censuses show that metropolitan expansion processes in Israel are gradual. Mobile phone tracking data for 2013 reveal similar patterns, confirming the urban structure’s stability and the reliability of tracking data as a means of assessing metropolitan processes. The “island state” context supports growing monocentricity, but, when it comes to commuting and travel for other purposes, Israel is not yet a metropolitan state; metropolitan boundaries are not as fuzzy and rapidly changing as expected. 相似文献
13.
Madhuri Sharma 《Applied geography (Sevenoaks, England)》2012,32(2):310-323
Racial/ethnic diversity in the United States has increased significantly in recent decades, with minority groups now accounting for almost one-third of the total population. At the same time, growing diversity has spread into rural and non-metropolitan areas. Research suggests that changing diversity in the ‘New South’ has seen growth of non-Black communities. The question, however, is the degree to which increasing diversity equates with increasing intermixing or, alternatively, whether racial/ethnic clusters retain their prominence. This paper examines the geographic manifestations of growing racial/ethnic diversity within intra-urban context, using census-tracts as scale of analysis in the metropolitan statistical area (MSA) of Knoxville in Tennessee. The statistics used for analyzing intra-urban variations include Diversity Score, Theil Entropy Index, and Location Quotient. Tract and Block-group data for White, Black, American Indian, Asian, All Others and Hispanic are used for computing these indices. This paper concludes that diversity has increased during 1990-2000, and has dispersed into suburban counties. However, segregation and clustering for certain minority groups has also increased, in particular African-Americans still remain the most segregated and most clustered community confined to specific geographic locations. This research holds significance as local economic development patterns are very much guided by the geographic variability of human and social capital. Applied research can suggest avenues for growth and can help rebuild local communities. This paper will also contribute to literature focusing on methodological challenges in measuring diversity and its geographic manifestations. 相似文献
14.
15.
Rowland RH 《Soviet geography》1986,27(9):638-658
"This paper investigates the post-census growth of metropolitan areas and large cities in the USSR from 1979 to 1985. The Soviet population continues to be increasingly concentrated in large metropolitan areas and large cities, and although suburbanization occurs within metropolitan areas, a striking feature is that all central cities continue to grow and typically contain the vast majority of the metropolitan population. This reflects the fact that individual large cities continue to loom large, despite policies to limit their growth. Although the growth rates of large cities have slowed, so have those of smaller towns, and a merging of growth rates by size class is occurring." 相似文献
16.
Jill S.M. Coleman 《The Professional geographer》2013,65(2):190-206
Although much research has been done linking meteorological variables individually with various aspects of human health, few studies have considered the collective impact of weather. This study examines the relationship among ten synoptic-scale weather patterns and daily cause-specific human mortality rates for metropolitan areas in the central United States during the 1978 to 1998 autumn and spring seasons. The results show that distinctive changes in mortality rates are often associated with one or two of the more moderate synoptic types, displaying notable spatial and temporal variability. The occurrence of the Eastern Zonal (EZ) pattern during spring and the East Coast Trough (ECT) pattern during autumn seems to invoke the most significant increased mortality response across all causes of death and metropolitan statistical areas. For the EZ and ECT types, the largest adverse response occurs for locations influenced by cold, anticyclonic situations and atmospheric stability. 相似文献
17.
We focus on the association between the institutional factor of union contract coverage rates among workers and the variation in income inequality across a set of sixty-four metropolitan areas of the United States for the years 1990, 2000, and 2010. We use market variables of relative skills and relative education and demographic variables of race and gender as controls in our regression models. We also specify a set of models that substitute right-to-work status for union contract coverage rates. Our primary finding is that union contract coverage rates are temporally consistent and significant negative covariates of income inequality, as measured by Gini coefficients, across the metropolitan areas. Further, metropolitan areas in right-to-work states have consistently and significantly higher levels of inequality than expected given the control variable effects. Our interpretation of the primary finding is that issues of labor power and class play a clearly important role in contributing to income inequality in the set of metropolitan areas used in the analysis. 相似文献
18.
中国大都市多中心空间演化过程的非均衡动态模拟 总被引：1，自引：0，他引：1
构建了一个基于垄断竞争、规模经济、空间成本、消费者多样化偏好以及商品和服务差异化的大都市多中心空间结构模型,并整合基于agent的建模,借助非均衡(out-of-equilibrium)动态模拟,探讨了人口规模和消费需求、区域间和区域内商业产品及服务的替代弹性、固定成本投入、区位和交通条件等因素的"持续"变化对的大都市空间结构演化的影响过程。模拟表明:以商业为代表的经济活动往往集聚在具有区位优势、规模经济和消费能力的大都市传统中心,而交通条件的持续改善、新兴郊区次中心与传统城市中心之间以及城区内部商业产品和服务的不断差异化对大都市的多中心空间结构有重要影响,但影响的程度不同。更重要的是,大都市的人口规模和消费能力对新兴郊区次中心的形成作用显著。 相似文献
19.
Cities were once thought to be crucibles of secularisation, where the retreat from religion and its expression would be most pronounced. This decline in faith was linked to the heightened levels of heterogeneity and cosmopolitanism within cities. However, there is recent evidence of both the continuation and of the recession of the secularisation process in contemporary Western societies, with the mix and pace of these trends being quite unique to different countries. Significantly, this combination of processes has been argued to be part of a ‘post-secularist’ paradigm. Drawing on census data, this paper examines the spatial patterns of religious affiliation and non-belief in the Australian city of Sydney. Sydney has divergent geographies of faith and non-faith indicating the spatial multiplicities of religious belief. The decrease in Christianity in some areas of the city has been matched by an increase in non-Christian faiths, while in other areas there has been little change. Some parts of the city—especially those areas with a strong mix of affluence, diversity and cosmopolitanism—betray the strongest levels of secularisation and the retreat of faith. At least five geographies of faith and non-belief are recognisable within Sydney. While post-secularisation has been recognised as internationally uneven, this research demonstrates that it is also uneven across a world city like Sydney. The Sydney variations in (de)secularisation reflect city-based effects, including the historic and contemporary patterns of immigrant settlement, established and emerging religious communities, the segmented geographies of class and affluence, and the development of zones of cosmopolitanism. The findings point to the need for further research on the micro-geographies of religious belief and non-belief and community relations, and the on links between religious communities and civil society. 相似文献
20.
《Urban geography》2013,34(6):552-566
Responding to previous analyses that assume that places are passive recipients of the various macro-level social phenomena associated with concentrated urban poverty, I hypothesize that concentrated urban poverty takes on different forms in different places as a result of how macro-level social phenomena are mediated by locally specific structures. To investigate how concentrated urban poverty takes on different forms in different places, I first decompose the poverty rates of all high-poverty urban neighborhoods in the United States into their race-specific rate and composition effects, and classify high-poverty neighborhoods based on these decomposition values. The results of the analysis demonstrate that poverty in a majority of the high-poverty neighborhoods in the United States is undoubtedly affected by geographically specific processes. For example, within one set of high-poverty neighborhoods, poverty is associated with both the lack of economic opportunity and high rates of class-based residential segregation within mixed-race immigrant ethnic/immigrant enclaves in large gateway cities. A second set of high-poverty neighborhoods, located in the metropolitan areas of the southern United States, has high rates of poverty because of the residential segregation and geographic concentration of poverty-prone African Americans. And lastly, among a third set of tracts, poverty experiences in African American ghettos are linked to declining economic and social opportunities and class-based residential segregation within large manufacturing cities. A set of recommendations for additional research includes addressing how one-size-fits-all anti-poverty public policies should be modified for the specific needs of each type of high-poverty neighborhood. [Key words: context, poverty, segregation, employment, race, ethnicity.] 相似文献