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Driving forces facilitate or inhibit land‐use / land‐cover change. Human driving forces include political, economic, cultural, and social attributes that often change across time and space. Remotely sensed imagery provides regional land‐change data for the Northern Piedmont, an ecoregion of the United States that continued to urbanize after 1970 through conversion of agricultural and forest land covers to developed uses. Eight major driving forces facilitated most of the land conversion; other drivers inhibited or slowed change. A synergistic web of drivers may be more important in understanding land change than individual drivers by themselves.  相似文献   

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ABSTRACT. The geography of terrorism remains underexplored. By focusing on the spatial patterns of terrorist attacks, the settings and land uses in which attacks occur, and the methods used to perpetrate violence, this analysis helps build a theory of terrorism geography. Between 1 January 1997 and 11 September 2005, 178 terrorist incidents occurred in the United States. Analysis of these incidents suggests three insights. At the national scale, terrorism in the United States clustered in large urban areas, with regional differentiation of terrorist motives and targets. At the scale of individual attack sites, terrorist motivations pinpointed offices, clinics, and public spaces; right‐wing violence, military, government, and infrastructural targets; and religious terrorism, commercial and special land uses. At the scale of individual interactions, terrorists crossed paths with victims in various ways. For example, the 2001 anthrax‐attack letters and lone‐wolf terrorism created alternative intersections of perpetrators with victims.  相似文献   

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Nonemployment income from investments, pensions, welfare benefits, and so forth provides one third of total personal income in the United States. Spatial concentrations of this income occur in places such as Florida, Michigan, Arkansas and the Great Plains. These concentrations result largely from the presence of older persons who are the principal recipients of nonemployment income. In turn, spatial concentrations of older persons result from “aging in place,” which typifies the Great Plains, or from amenity-bound immigration by older persons, which characterizes Florida.  相似文献   

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ABSTRACT. The emerging scholarly literature on contemporary African migration to the United States has primarily focused on populations concentrated in large urban areas. In contrast, this study considers the experiences of African university students living in two distinctly different places, Eugene, Oregon, and Washington, D.C., to examine how the context of the local host community shapes ethnic and national identities. Specific contextual variations under consideration are the extent to which newcomers have contact with coethnics/conationals and access to material and nonmaterial culture. Results based on thirty‐six in‐depth interviews show that, despite easy access to coethnics, some students in the Washington metropolitan area readily identified with conationals. Likewise, in the absence of coethnics in Eugene, many students described strengthening national identities; and, in the absence of conationals, they have constructed panethnic African identities. Additional research into the experiences of newcomers in various host‐community contexts is needed.  相似文献   

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内蒙古耕地重心移动及其驱动因子分析   总被引:33,自引:1,他引:33  
简单回顾了内蒙古垦荒历史,并用内蒙古自治区近50年的统计数据计算出1949年~1996年不同年份的全区耕地重心及人口重心,在此基础上得到了内蒙古耕地重心及人口重心均向东北方向移动的结论,分析了耕地重心移动的驱动因子,提出了土地持续利用的几点建议。  相似文献   

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在分析1996~2004年福州市城市化发展和土地利用动态变化的基础上,探求城市化与土地利用变化之间的内在关系,然后选取代表性指标对建设用地和耕地数量与各自的驱动变量进行相关性分析,最后构建了驱动模型。结果表明:(1)1996-2004年,福州市土地利用结构变化明显,土地利用空间变化较大;(2)地均GDP的提高、GDP总量和全社会固定资产投资额的增长是建设用地拓展的主要驱动力;(3)耕地变化的最主要驱动力则是建设用地占用、粮食播种面积和耕地保护政策强度。  相似文献   

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The use of historical sources in geomorphological analysis has had a long tradition in geography and is now undergoing a resurgence. A substantial body of data is available, and the search for it should extend from the National Archives to state and company records and county and city offices.  相似文献   

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ABSTRACT. Levels of alcohol consumption are a major public health issue. This study aims to gain a better understanding of how geographical patterns of religious affiliation in the United States relate to geographical patterns of alcohol consumption. We explored state‐level correlations between alcohol consumption and religious adherence. Although we found no statistically significant correlation between overall religious adherence rates and current or binge drinking rates, states with higher adherence rates were significantly more likely to have high proportions of binge drinking among current drinkers. Yet, regionally, we found a strong inverse correlation in the Southeast and a strong positive correlation in the Midwest and Northeast between adherence rates and current and binge drinking rates. These geographical differences were largely explained after stratifying by major religious denominational groupings. States with high Catholic adherence rates tended to have higher drinking rates, whereas states with high Evangelical Protestant adherence rates tended to have lower drinking rates. These findings suggest that the relationship between religion and alcohol may be denomination‐specific and challenge the lay perception that religious adherence per se is associated with less alcohol consumption and less excessive drinking among those who drink.  相似文献   

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The US Hispanic population has grown rapidly over the last two decades and remains geographically concentrated in nine states. Redistribution away from core states through internal migration has been largely offset by heavy immigration to traditional areas of Hispanic concentration. Geographical patterns of Hispanic miration show broad similarities to overall patterns of population redistribution in the United States. New York and California serve as key spatial redistributors or pivots in the Hispanic migration system.  相似文献   

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Scholarly literature on newly incorporated municipalities (nims ) often focuses on why nims form. Instead of asking why nims formed, however, we ask why nims stopped forming. We first establish a temporal context for nims from 1950 to 2010, revealing an 86.2 percent decline in nim formation. The decline, triggered by stricter laws, smaller annexations, declining suburbanization, and boundary ossification, has profound implications for metropolitan fragmentation and public choice. We then establish a state‐level spatial context, revealing distinct high‐nim , low‐nim , and flux states due to boundary ossification, growth, and state/regional policy stimuli such as consolidation efforts, grants, and growth management provisions.  相似文献   

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AVOIDING THE DEMISE OF GEOGRAPHY IN THE UNITED STATES   总被引:1,自引:0,他引:1  
This is the second of two articles about challenges that confront geography departments in a changing academic environment. College enrollment trends and tightening budgets are placing geography programs in jeopardy because the discipline is not considered by society to be indispensable. Departmental survival in a period of retrenchment may depend upon successfully demonstrating utility and quality, identifying unfilled niches in individual institutions, developing new interdisciplinary organizational arrangements, or finding ways to strengthen geography's position in governmental definitions of useful academic training.  相似文献   

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《Urban geography》2013,34(4):334-354
In metropolitan areas, firms trade-off land and information costs. Firms that gain the most from access to the knowledge and know-how of other firms in the same sector are willing and able to pay for expensive central city land. We found that legal services, advertising, and accounting and auditing services are the most centralized services in the 74 largest metropolitan areas of the United States. Maps of seven fast-growing business and professional services in Phoenix, Arizona, show that central city services are mainly located in the CBD. Using a logarithmic function, we found that service jobs are more decentralized in the larger metropolitan areas and in metropolitan areas outside the Northeast. Analysis of disaggregate service sectors shows significant intersectoral variation in this relationship.  相似文献   

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This paper focuses on the large‐scale land use and land cover changes that have taken place in Sarawak state, East Malaysia over the three decades of 1972‐2002. Results are presented from a detailed land use and cover change (LUCC) study in the Niah River catchment using satellite imagery, questionnaire surveys and interviews. Successive waves of land cover changes have taken place. Large forest areas have been logged and gradually replaced by oil palm plantations, which now occupy more than 40 per cent of the total land area in the catchment. Concurrently, small‐scale farming systems have also changed. Formerly dominant Iban shifting cultivation practices are increasingly being replaced by cash crop production on permanent fields and impacted by off‐farm activities involving many ethnic groups. It is argued that land cover changes are continuous and complex processes involving a large number of variables which can be analysed for different time periods at various scales.  相似文献   

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