首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1496篇
  免费   47篇
  国内免费   23篇
安全科学   61篇
废物处理   65篇
环保管理   322篇
综合类   125篇
基础理论   473篇
环境理论   4篇
污染及防治   297篇
评价与监测   106篇
社会与环境   83篇
灾害及防治   30篇
  2023年   11篇
  2022年   25篇
  2021年   33篇
  2020年   26篇
  2019年   30篇
  2018年   38篇
  2017年   51篇
  2016年   54篇
  2015年   51篇
  2014年   53篇
  2013年   128篇
  2012年   71篇
  2011年   120篇
  2010年   71篇
  2009年   87篇
  2008年   104篇
  2007年   95篇
  2006年   77篇
  2005年   56篇
  2004年   55篇
  2003年   51篇
  2002年   33篇
  2001年   17篇
  2000年   14篇
  1999年   19篇
  1998年   17篇
  1997年   17篇
  1996年   18篇
  1995年   14篇
  1994年   18篇
  1993年   14篇
  1992年   17篇
  1991年   8篇
  1990年   5篇
  1989年   8篇
  1988年   6篇
  1987年   3篇
  1986年   5篇
  1985年   2篇
  1984年   3篇
  1983年   6篇
  1982年   6篇
  1981年   6篇
  1980年   7篇
  1978年   4篇
  1976年   2篇
  1975年   3篇
  1973年   2篇
  1959年   1篇
  1957年   1篇
排序方式: 共有1566条查询结果,搜索用时 171 毫秒
371.
Joanna Macrae 《Disasters》1998,22(4):309-317
Over recent years, the humanitarian community has been under increasing scrutiny and attracted harsh criticism. This mounting critique of humanitarianism has shifted from being concerned primarily with the poor functioning of the humanitarian system to one targeted on basic humanitarian values. This paper is concerned to understand the factors driving the attack on humanitarian values. It identifies four apparently disparate groups who are interested in attacking these values: the anti-imperialists, the realpolitikers, the developmentalists and the neo-peaceniks. It concludes that unless humanitarian actors are aware of these diverse threats to their values and operations, they risk being co-opted or marginalised.  相似文献   
372.
This is a report of a social environmental audit of urban renewal schemes based on an investigation of environmental hazard risk perceptions of people in their homes, workplaces and other places of urban activity, in the vicinity of five major renewal sites in Sandwell, West Midlands, UK. The selection of the renewal schemes was designed to incorporate a range of the types of contemporary urban development in the UK. People were asked to give a scaled score response reflecting the perceived magnitude of risk of each of a series of hazards. Each person was asked to give two responses to each hazard, one response referring to the actual present situation post-renewal and the second response referring to an imagined present situation as if renewal had not occurred. The statistical analysis of the responses suggested that urban renewal had brought about an increase in certain perceived environmental risks and not necessarily a more desirable perceived environmental state than the alternative of dereliction.  相似文献   
373.
Summary The June 1992 United Nations Conference on Environment and Development (UNCED) was the largest and most well attended United Nations conference of all time. The litmus test for the long-term will be whether the promises and pledges made at Rio can be taken forward by way of a process that gradually moves human society towards a more equitable and environmentally sustainable form of development. This paper focuses on two organisations that look set to play an important role in that process: the World Bank's experimental Global Environment Facility and the nascent United Nations Commission on Sustainable Development. It is argued that both these bodies must find a way to respond to the conflicting demands of developed and developing nations if their efforts are not to be stymied by the same kind of international disagreements which characterised the negotiations preceding the Summit.The author is a research associate at the Centre for Social and Economic Research on the Global Environment (CSERGE), a UK Economic and Social Research Council funded centre located jointly at the University of East Anglia and University College London. He is currently engaged in a long term research project which seeks to elucidate how governmental, business and other agencies perceive the uncertain threat of global environmental change, and how they are adapting to it.  相似文献   
374.
The paper examines the application of a spatial‐perceptual approach to the wilderness management issue of preserving natural ecological processes while also permitting appropriate wilderness use in protected areas. An approach to delimit the spatial extent of multiple perceptions of wilderness held by backcountry users is used—the wilderness perception mapping (WPM) methodology. The results obtained from employing the WPM.methodology are considered for the North West Nelson region of New Zealand. The map product provides new and useful information that has applicability to protected areas management. The role of WPM is discussed with reference to wilderness management in North West Nelson and New Zealand, and to protected areas management in general. The study demonstrates how a technology can be combined with a critical and sensible analysis of needs and procedures to give useful results, and highlights the value of applied interdisciplinary research.  相似文献   
375.
376.
Aims: (1) to examine areas of controversy which arise in the occupational health course curriculum, and (2) to identify best practices in addressing and resolving those controversies.Methods: A literature review reveals that occupational health practice and policy contain many controversies. The BSc and MSc occupational health course curricula at the Nottingham Trent University contain toxicology, epidemiology, occupational hygiene, and occupational health policy. These subjects raise questions which may be controversial and have been so identified by students —through the collection, interpretation, dissemination and presentation of data; different methodologies; funding of particular types of occupational health research; use of data in setting standards, and making policy. Case studies on coal mining, coal gas industry and formaldehyde are used on the courses to examine the controversial topics raised by students.Results: Evaluations reveal that controversy should be openly acknowledged in the teaching of occupational health. Those providing courses need to be aware of the tensions and problems which may arise when controversy emerges on courses. Methods are available for raising the subject and dealing with it as a positive pedagogic tool. This entails the use of case studies which examine several different perspectives and approaches to the controversy linked to comparative and historical studies.Conclusions: The teaching of occupational health to clinical and non-clinical students, from a range of backgrounds, is not a value-free activity. Controversial questions central to key topics in occupational health relating to science and technology as well as policy will always emerge. These should be openly recognised and discussed on courses through, for instance, case study material which identifies and analyses a range of approaches to the subject.  相似文献   
377.
ABSTRACT: A water supply network optimization model called MODSIM3 is presented as a decision-support tool for aiding city staff in determining how best to utilize and exchange existing and potential water supplies with other users in a river basin. The model is applied to the City of Fort Collins, Colorado, water supply system as a means of determining optimum ways the City can utilize direct flow rights, storage rights, and exchangeable waters from various sources. Results clearly confirm both the benefits of the use of exchanges and the value of MODSIM3 as a water supply planning and management tool.  相似文献   
378.
ABSTRACT: Country level electoral data were used to analyze the voting patterns of eight water related constitutional amendment elections. Both water quality enhancement amendments (1971, 1976), and three of six water development amendments (1957, 1962, 1966) have been ratified, thus establishing a statewide policy of reservoir development, a funding mechanism to implement such a policy, and the creation of a water management agency. Begining with the 1969 election, a West Texas-East Texas regionalized voting pattern has emerged, resulting in the defeat of three amendments (1969, 1976, 1981) intended to provide additional funding for water development. This regionalization reflects different climatic, physiographic, economic, and locational factors, and represents a potential obstacle to coordinated water management in Texas.  相似文献   
379.
Marine sediment toxicity tests are widely applied in monitoring programs, yet relatively little is known about the comparability of data from different laboratories. The need for comparability information is increased in cooperative monitoring programs, where multiple laboratories (often with variable skill levels) perform toxicity tests. An interlaboratory comparison exercise was conducted among seven laboratories in order to document the comparability of sediment toxicity measurements during the Bight'98 regional sediment survey in southern California. Sediments from four stations in Los Angeles and Long Beach Harbors were tested using a 10-day survival test of the amphipod Eohaustorius estuarius. All laboratories successfully performed the sediment test and associated reference toxicant test. Statistically significant differences were found in mean amphipod survival rates among some laboratories for the field-collected sediments, but there was little evidence of a consistent bias among laboratories. Although the reference toxicant test indicated a five-fold variation in test sensitivity among laboratories, these results were not accurate predictors of interlaboratory performance for the sediment tests. The laboratories demonstrated excellent concordance (Kendall's W = 0.91) in ranking the field-collected sediments by toxicity. Agreement on classifying the sediments into categories (nontoxic, moderately toxic, and highly toxic) based upon the percent of survival was best for highly toxic sediments. An analysis of test precision based upon the variance among replicates within a test indicated that the measured survival rate for a sample may vary by up to 12 percentage points from the actual response.  相似文献   
380.
The decline of red spruce (Picea rubens Sarg.) in montane forests of the northeastern United States has been previously reported. The objective of this study was to assess spatial patterns, if any, in standing dead red spruce stems in the Adirondacks of New York and northern Appalachians of Vermont, New Hampshire, and Maine. A stratified random sample of 19 mountains along a west to east transect in the Adirondacks and the northern Appalachians showed that the live basal area of all species was highest in the White Mountains (34.6 m2 ha–1) and lowest in the Adirondack Mountains (23.7 m2 ha–1) in the Green Mountains was significantly lower than in any other region. Intact standing dead red spruce in the Adirondack and Green Mountains (30%) was significantly higher than that in the three eastern clusters (14%). The amount of intact standing dead red spruce trees increased with elevation in only the western part of the region. With the exception of the Adirondacks, there was a greater average percent dead red spruce on the west side than on the east side of each mountain. The sum of standing dead for other tree species (average 13%) showed no statistically significant patterns with region, elevation or aspect, and was significantly lower than the amount of total dead red spruce (average 42%). The standing dead red spruce patterns we observed cannot be associated with any specific causal factors at this time.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号