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1.
孙盼盼  余青 《热带地理》2020,40(6):1136-1149
政策是保障和推动风景道建设与发展的重要措施、手段、依据和基本准则。文章围绕美国风景道政策演进这一主线,从演进背景、政策类型、政策主体、政策主题、政策手段等5个方面,深入剖析其百年演进历程,并在此基础上刻画和识别其演进特征。结果表明:1)美国风景道政策演进历经“萌芽酝酿”“起步探索”“成长发展”“转型变革”4个时期,是一个动态演变的历史过程,标志性政策的出台促进与推动政策变迁迈入新的进程;2)美国风景道政策演进受社会文明与思潮、经济与生态环境发展、交通建设和旅游需求、风景道自身发展等内、外各种因素的共同影响;3)法案、技术指南和研究报告“三位一体”,共同促进美国风景道政策演进;4)历经百年变迁,美国已形成由交通部门主导、多部门跨部门联合、注重公众参与的政策制定主体格局;5)美国已形成一套相对完整的风景道政策体系,涉及“建管养运”各方面。最后,基于美国经验,结合中国风景道政策现状和问题,提出未来中国应遵循风景道政策演进规律,考虑内、外影响因素,进一步丰富政策类型、设立风景道主管或牵头部门、关注“建管养运”全过程等。  相似文献   

2.
Religious pluralism is an important and contested topic within the literature on religion. This article explores the spatiality of religious diversity in the United States. It opens with a summary of major conceptual perspectives on the causes and consequences of religious diversity. Second, to unpack the geography of U.S. religious diversity, the article uses Glenmary and Polis data for 2000 to construct four indexes of diversity and presents these results with both choropleth maps and Dorling cartograms. It explores the relation between the distribution of denominations and county population size. The analysis reveals that the most diverse regions include the Pacific Northwest, a broad belt stretching from Denver to Pittsburgh, and central Florida, and the least diverse parts are dominated by Mormons, Baptists, and Catholics. Indexes more sophisticated than the simple number of denominations per county are sensitive to the internal configuration of adherents and reflect a more complex relationship in which population size is not assured of generating greater degrees of religious diversity.  相似文献   

3.
文章基于金融危机后美国实施再工业化战略的背景,根据美国从2005年到2011年的经济数据,运用空间分析法、技术密度法和投入产出法综合剖析了再工业化战略实施后美国制造业的发展变化及影响。文章认为,再工业化战略实施后美国制造业的发展水平开始提升;制造业发展的变化增强了产业间的互动,促使了都会区职能的演变,改变了美国经济的发展路径。  相似文献   

4.
欧美景观地理学的新进展及其启示   总被引:4,自引:0,他引:4  
文章从文化景观、景观概念、景观解释、景观与文化、景观政治学等方面阐述了欧美景观地理学的新进展。目前,欧美文化地理学正在重新整合,文化景观研究是其核心。针对景观的不同用法(艺术上的,社会科学上的),提出了4种专业化的景观解释模型。景观政治学是新文化地理学的关键建设领域,甚至有人把它当作景观解释的中心。地理学者对文学的兴趣日益增加,并将不同的文学形式看作是研究景观意义的途径。  相似文献   

5.
Climate change across the contiguous United States is investigated using a modified version of Thornthwaite's climate classification scheme. This approach allows both moisture and thermal conditions to be examined simultaneously for a better assessment of multivariate climate change. Changes in area of different climate types over time is determined using the climate year approach and the spatial nature of climate change is examined by computing climate types based on averages from three thirty-year periods over the twentieth century. Over the study period from 1895 to 2005, statistically significant changes in areal coverage of different climate types have occurred. In the eastern half of the country, climate divisions have become wetter and changed to moister climate categories. The most prominent change has occurred in the Deep South, where the climate has changed to both a lower thermal category and a wetter moisture category. Much of the country has experienced positive temperature trends, but only climate divisions in the Southwest and Upper Midwest show changes to higher thermal categories.  相似文献   

6.
Hazardous waste is generated in the production of almost all consumer goods, especially those that contain plastic. The United States is the world leader in generating hazardous waste with 214 million tons produced in 1995. The majority of this waste was wastewater generated by the fifty largest generating facilities, disproportionately concentrated along the western Gulf Coast. The largest facilities also treat most of their waste on site, particularly wastewater. Most smaller generators send waste an average of 200 miles for treatment or disposal. Among both citizens and state governments there is resistance to local siting of waste facilties. Local resistance has convinced businesses or government agencies to look elsewhere to site a proposed facility. State efforts to directly control the flow of hazardous waste have not been successful due to court challenges from industry and subsequent decisions that state restrictions violate the Commerce Clause of the U.S. Constitution. Taxes on both in‐state and out‐of‐state waste have proven effective at reducing in‐state waste disposal.  相似文献   

7.
Freshwater resources are particularly limited in the Southeastern United States. In recent years, severe summer droughts have placed substantial strain on municipal and industrial water resources, emphasizing the need for further research on the causes of long-term moisture deficits. Previous research has identified a Southeast drought region and specific low-frequency ocean-atmosphere influences on drought. In this article, we identify three distinct subregions of low-frequency summer drought variability in the Southeastern United States using principal components analysis. Multidecadal drought variability is most pronounced in the Southeastern Atlantic Coastal States (SEACS) subregion. The SEACS drought variability is significantly associated with ocean-atmosphere variability in the Atlantic and Pacific basins. The significance of ocean-atmosphere influences on drought in the Southeast is spatially confined within only the SEACS subregion. The Eastern Gulf States (EGS) subregion exhibits a long-term increase in summer moisture that is significantly associated with Northern Hemisphere surface temperature increases during the last century. The peninsular Florida subregion is characterized by high-frequency drought variability that is not associated with any of the climate indexes included in this study.  相似文献   

8.
美国外商直接投资区域分异特征研究   总被引:1,自引:1,他引:0  
八十年代以来,大量外商直接投资流入美国,逐步使美国成为国际直接投资的净流入国,文章分别以美国大区和洲为研究地域单元,多角度地分析了美国外商直接投资区域分异特征,主要研究结论如下;在大区层面上,各大区的投资比例具有不平衡性,高投资比例的大区与低投资比例的大区之间的不平衡性具有稳定性,且低投资比例的大区比高投资比例的大区的稳定性强,在洲际层面上,外商直接投资分布有沿海性倾向,呈“U”型分布状态;投资密度以密西西兹河为界,东西对比格局强烈;制造业带所在地区整体位次上升快,显示了制造业带的较强的聚集效应,一般而言,人口少,面积大的洲,人均投资额高。  相似文献   

9.
Maxwell T Boykoff 《Area》2007,39(4):470-481
The journalistic norm of 'balanced' reporting (giving roughly equal coverage to both sides in any significant dispute) is recognised as both useful and problematic in communicating emerging scientific consensus on human attribution for global climate change. Analysis of the practice of this norm in United States (US) and United Kingdom (UK) newspaper coverage of climate science between 2003 and 2006 shows a significant divergence from scientific consensus in the US in 2003–4, followed by a decline in 2005–6, but no major divergence in UK reporting. These findings inform ongoing considerations about the spatially-differentiated media terms and conditions through which current and future climate policy is negotiated and implemented.  相似文献   

10.
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12.
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   

13.
《自然地理学》2013,34(2):105-129
Many remote locations in the Northern Hemisphere have a spring peak, rather than a summer peak, in ground-level ozone concentrations, and the principal cause is presumed to be stratosphere-troposphere exchange (i.e., stratospheric intrusions). Grand Canyon National Park (GCNP) in northern Arizona also has a spring peak, and the purpose of this study is to explore the impact of stratospheric intrusions and another process synoptic-scale pollutant transport on ground-level ozone levels at GCNP from 1996 to 2000. The primary methods involve the stratification of days to identify stratospheric-intrusion days and the compositing of days to assess the impact of pollutant transport on ground-level ozone concentrations. Results indicate that stratospheric intrusions contributed little to the ozone budget at GCNP. In fact, atmospheric pollution originating in southern California was the likely cause of the May peak in ozone. The transported pollution also appeared to be responsible for high ozone days during all spring months. Tracer-based research (i.e., beryllium-7 and methylchloroform) at multiple locales in the southwestern United States is needed to fully confirm the weak impact of stratospheric intrusions and the strong contribution of ozone and its precursors originating in southern California.  相似文献   

14.
We investigate spatial patterns of residential and nonresidential land use for 257 United States metropolitan areas in 1990 and 2000, measured with 14 empirical indices. We find that metropolitan areas became denser during the 1990s but developed in more sprawl-like patterns across all other dimensions, on average. By far, the largest changes in our land use metrics occurred in the realm of employment, which became more prevalent per unit of geographic area, but less spatially concentrated and farther from the historical urban core, on average. Our exploratory factor analyses reveal that four factors summarize land use patterns in both years, and remained relatively stable across the two years: intensity, compactness, mixing, and core-dominance. Mean factor scores vary by metropolitan population, water proximity, type, and Census region. Improved measurement of metropolitan land use patterns can facilitate policy and planning decisions intended to minimize the most egregious aspects of urban sprawl.  相似文献   

15.
Migration is primarily motivated by economic reasons, but people also move for a variety of other purposes, including a desire for political and economic freedom. Although freedoms are often thought of as dominant reasons for international migration in political states with federal systems of governments, migration across internal political borders also takes place to take advantage of local differences in political and economic regulations, taxes, and public goods. Using the combined Internal Revenue Service/Census Bureau state-to-state migration data for 1995 to 2010, we examine the relationship between economic freedom and migration and its impact on state-level income change. We find that economic freedom is positively associated with income change due to net migration but not associated with gains or losses from income differences between in- and outmigrants. In general, states with higher or lower levels of economic freedom gained or lost income due to migration.  相似文献   

16.
ABSTRACT

Changes in growing season length (GSL) are of concern for agricultural, phenological, economic, epidemiological, and bioclimatological reasons. This research identifies spatial and temporal changes over the last several decades in GSL, along with the day-of-year of the last spring freeze and first autumn freeze, for the northeastern United States – a region particularly susceptible to such changes due to the large population and intense economic activities. Results suggest that growing season has significantly increased in length since 1980 as compared to prior to 1980, and both spatial and temporal variation in GSL has decreased for the region over time. Changes to GSL for this region are driven more by a shift in the first autumn freeze date than the last spring freeze date. The areas of greatest increase in GSL in the pre- vs. post-1980 period tend to be in the high elevations, near large water bodies, and near the largest cities. Results will assist environmental planners as they prepare mitigation and adaptation strategies amid a changing environment.  相似文献   

17.
Postmaterialist theory suggests that under conditions of continuously expanding economic and personal security, younger generations will be less oriented to acquiring material goods and more committed than their older peers to attaining postmaterial social goals such as increased free self-expression and a healthy natural environment. Using the latest World Values Survey sample for the United States, ordinary least squares (OLS) and logit regressions are employed to test whether youth is a predictor of postmaterialism as theory suggests, and whether postmaterialism positively predicts environmental concern and individual actions in support of the environment. Age is found to be a negative and statistically significant factor in explaining variation in the postmaterialism index, and this index is in turn found to be a statistically significant positive factor in explaining individual environmental concern and activism. A combination of increased economic security and entrance of younger generations into adulthood could well matter for our environmental future.  相似文献   

18.
美国汽车工业经历了发展、兴旺、波折三个阶段,使国内的汽车工业的格局发生集中──分散──再集中的演变,但仍保持美国汽车国内市场的绝对优势。  相似文献   

19.
ABSTRACT

Rain-on-snow (ROS) has the potential to produce devastating floods by enhancing runoff from snowmelt. Although a common phenomenon across the eastern United States, little research has focused on ROS in this region. This study used a gridded observational snow dataset from 1960–2009 to establish a comprehensive seasonal climatology of ROS for this region. Additionally, different rain and snow thresholds were compared while considering temporal trends in ROS occurrence at four grid cells representing individual locations. Results show most ROS events occur in MAM (March-April-May). ROS events identified with rainfall >1 cm are more frequent near the east coast and events identified with >1 cm snow loss are more common in higher latitudes and/or elevations. Decreasing trends in DJF (December-January-February) ROS events were identified near the coastal areas, with increasing trends in the northern portion of the domain. Significant decreasing trends in MAM ROS are likewise present on a regional scale. Factors playing a role in snowpack depth and rainfall, such as movement of storm tracks in this region, should be considered with future work to discern mechanisms causing the changes in ROS frequency.  相似文献   

20.
This research examines changes to seasonal start dates (1948–2015) across urban locations in the eastern United States. For 25 cities, percentile-specific thresholds of temperature (Ta) and apparent temperature (AT) were used to define seasonal start dates. Seasonal changes were evaluated across four time periods: 0300, 0900, 1500, and 2100 UTC. Incorporating spatial and temporal variability into seasonal delineation, this research critiques the ways in which seasons are defined and builds on existing research regarding seasonal climate change. Both Ta and AT results generally indicate earlier starts to the summer and spring seasons, while the starts to winter and autumn seasons have been delayed. On average, a forward shift of 11 days was found for summer. Larger changes were found for AT thresholds when compared to air temperature alone. Temporally, the largest and most significant changes were found for the 0300 and 2100 observations. The observed changes to seasons have significant impact on a range of processes, including phenology and human health, and may be appropriate to consider further in future climatology studies.  相似文献   

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