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181.
The landscape of the conterminous United States has changed dramatically over the last 200 years, with agricultural land use, urban expansion, forestry, and other anthropogenic activities altering land cover across vast swaths of the country. While land use and land cover (LULC) models have been developed to model potential future LULC change, few efforts have focused on recreating historical landscapes. Researchers at the US Geological Survey have used a wide range of historical data sources and a spatially explicit modeling framework to model spatially explicit historical LULC change in the conterminous United States from 1992 back to 1938. Annual LULC maps were produced at 250-m resolution, with 14 LULC classes. Assessment of model results showed good agreement with trends and spatial patterns in historical data sources such as the Census of Agriculture and historical housing density data, although comparison with historical data is complicated by definitional and methodological differences. The completion of this dataset allows researchers to assess historical LULC impacts on a range of ecological processes.  相似文献   
182.
SUMMARY

Since the discovery of oil, the United Arab Emirates has undergone a process of rapid development, increasingly affecting the ecosystems of the country. Limited scientific literature dealing with these ecosystems is available, although a process of comprehensive ecological research has been initiated over the last few years. Further information on the soils, vegetation, fauna and climate are required in order to initiate a process of sustainable use of natural resources.

Abu Dhabi Emirate was surveyed for anthropogenic factors in its habitats using an off-road vehicle, a global positioning system (GPS) and satellite imagery. The emirate was divided into six geomorphological units. Livestock was found to be the most common anthropogenic factor and is believed to have caused degradation of the natural vegetation. Agriculture, silviculture and urbanization were common and caused habitat loss and fragmentation. Rubbish dumping, earth moving and car tracks were also widespread, whereas air pollution and fences were limited. Four of Abu Dhabi's geomorphological units were classified as low-impact zones, two as low- to medium-impact zones and one as a medium- to major-impact zone. Environmental Impact Assessments (EIA) and detailed ecological research were suggested as future mechanisms to implement sustainable development, and livestock control was suggested as a tool for habitat restoration.  相似文献   
183.
A disaster referred to by the press as the ‘UK flooding crisis’ occurred between December 2015 and January 2016. This study employed three different levels of analysis to identify a multidimensional perspective adopted in the disaster reporting of the British Broadcasting Corporation (BBC). These levels revealed details about the social actors and their interactions. The set of news exposed diverse viewpoints on the crisis, from loss and damage to distinct affected subgroups to the various social engagement actions of aid and the multiplicity of technical response measures. The conclusions highlight considerable social amplitude in the BBC's coverage; however, owing to the reductionist approach of this media communicator, the field of action involving different social actors was not very clear in the content of the news, particularly with regard to cohesion, conflict/obstruction, and concernthe concept of crisis in its essence. In addition, the paper suggests new questions for future reports. 1  相似文献   
184.
This paper provides an overall evaluation of the outcomes of the World Summit on Sustainable Development (WSSD), which took place in Johannesburg from 26 August to 4 September 2002, in a historical perspective, against the background of earlier major United Nations conferences and General Assembly resolutions on environment and development. It focuses on the political and institutional context of the WSSD and its preparatory process and explores its policy implications for future international cooperation on sustainable development in a globalizing world. Both the results of the formal intergovernmental negotiations and the new phenomenon of partnerships for sustainable development between governments, international organizations, the private sector and other major groups are analysed. The Johannesburg Declaration and the WSSD Plan of Implementation are shown to contain little in the way of political vision, credible new commitments and innovative approaches, likely to reinvigorate the implementation of the objectives of sustainable development as formulated in Rio. Though ostensibly designed to give a new political impetus to multilateralism, the WSSD rather revealed the inadequacy of intergovernmental political governance structures to address the social and environmental consequences of economic globalization.  相似文献   
185.
BACKGROUND: Seventeen states enacted graduated driver licensing (GDL) programs that were implemented from 1996 through 1999 and for which evaluations are of interest. METHODS: We received evaluation results reported for six states for which data were available. Summarizing results is difficult in other than the most global terms because of differences in pre-GDL programs, differences in GDL programs, and differences in evaluation methodology. RESULTS: All states identified some crash reduction among teen drivers following GDL implementation. This positive effect was observed across different geographic regions, and with different GDL programs. Simple counts are down-fewer teens are experiencing crashes and becoming injured. After calculating crash rates to adjust for changes over time in populations or licensed drivers, reductions generally were still found. Population-adjusted risks of injury/fatal crash involvement of 16-year-old drivers in Florida and Michigan were reduced by 11% and 24%, respectively. Population-adjusted risks of any crash involvement of 16-year-old drivers in Michigan and North Carolina were reduced by 25% and 27%, respectively. Reductions in night (restricted hours) crash risk were impressive in Florida, Michigan, and North Carolina. A comparison state design was only possible in the Florida evaluation, and results showed greater crash reductions under GDL. Change-point analyses of Michigan's crash data trends over time provided additional support of GDL's effectiveness in reducing crashes. DISCUSSION: Taken as a whole, and including the preliminary findings from California, Ohio, and Pennsylvania, these reports demonstrate the early effectiveness of GDL in reducing the crash risk of teen drivers. The impact of these studies and others to come will guide future research, practice, and policy.  相似文献   
186.
ABSTRACT The runoff from a series of watersheds in the United States is examined to determine if there are distinct trends present. The data are examined for the period 1931-1960 and the results compared with those obtained for the period from the beginning of record to 1960. A larger sample of streams with records of various lengths is also utilized. The data used are annual, seasonal, and monthly values. The streams are grouped geographically to determine if regional patterns exist. The runoff increased on the majority of streams for the period 1931-1960, but for the period from the beginning of record to 1960 most streams exhibited a negative trend. When geographical distribution is considered, the streams located in the interior of the continent show greater similarity of trend than do those on the continental margins.  相似文献   
187.
自上世纪70年代开始,美国相继出台了一系列环境法律法规,建立了完善的环境执法机构和有效的环境法执行机制,取得了很好效果。本文从立法、机构设置、职能分配和运行机制等方面对中美环境管理体制进行了研究,旨在借鉴美国先进经验和有益做法,提出完善中国环境管理体制的对策。  相似文献   
188.
A telephone survey was conducted in four countries in November 1998 to compare drivers in the United States with those in Australia, Canada, and the United Kingdom regarding their attitudes toward seat belts and belt use laws. More than 90 percent of the 2251 respondents said they thought seat belts are effective, but self-reported belt use was significantly lower in the United States than in the other countries. Respondents in Australia and the United Kingdom had similar views about what they thought were important reasons for using seat belts and had the highest self-reported use. Reasons given for using belts by Canadian and US respondents were quite similar to one another, yet US respondents had significantly lower self-reported use rates, a difference thought to be due to vigorous enforcement of the law in Canada. US drivers were less likely than Australian and UK drivers to say they used belts out of habit, to avoid a ticket, or because it is required by law and more likely to say they used belts for situational reasons. US drivers were least likely to be in favor of belt use laws. Canadian drivers reported the most experience being checked by police for belt use and were most likely to think that nonusers would be caught. US drivers in primary enforcement jurisdictions were more likely than those in secondary jurisdictions to think that drivers not using belts would be caught and more likely to say they always used belts. Results of this survey indicate that seat belt use in the United States could be increased by adoption of primary enforcement laws and highly visible enforcement programs of the type used in Canada, and that seat belt use could be increased in all countries by increasing the penalties for nonuse.  相似文献   
189.
Studies dealing with media coverage of climate change have increased steadily over the last decade or so, alongside the media coverage of climate change itself. This article aims to contribute to this growing literature on two levels: to deepen understanding of distinctive patterns of language use across nations speaking a common language and to demonstrate the usefulness of a new approach for finding such patterns. Articles in The (London) Times and the New York Times, published between 2000 and 2009, were analyzed using methods related to computational linguistics. Results show that the US seemingly still constructs climate change as a problem, whereas the UK focuses on finding solutions for the (established) problem of climate change. This linguistic and conceptual gap may hamper mutual understanding and the crafting of global climate change mitigation policies.  相似文献   
190.
This paper describes a recent study in the UK aimed at identifying how policy makers might more effectively encourage pro-environmental behaviours amongst their target audiences. The study included analysis and synthesis of theories and models of behaviour change, a range of current policy programmes and instruments and ‘real world’ practices of individuals, households, groups and organisations.The paper highlights some important considerations for future policy within the UK and, more widely, for other countries aiming to introduce comprehensive and multi-level policy programmes to encourage pro-environmental behaviours. To this end, it emphasises the complex and non-linear nature of environmental behaviours and, thus, the importance of adopting multi-levelled and multi-instrument integrated policies across whole systems of delivery.  相似文献   
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