全文获取类型
收费全文 | 138篇 |
免费 | 5篇 |
专业分类
安全科学 | 8篇 |
废物处理 | 3篇 |
环保管理 | 39篇 |
综合类 | 10篇 |
基础理论 | 40篇 |
污染及防治 | 30篇 |
评价与监测 | 6篇 |
社会与环境 | 3篇 |
灾害及防治 | 4篇 |
出版年
2021年 | 1篇 |
2020年 | 2篇 |
2019年 | 1篇 |
2018年 | 1篇 |
2017年 | 7篇 |
2016年 | 5篇 |
2015年 | 3篇 |
2014年 | 2篇 |
2013年 | 7篇 |
2012年 | 9篇 |
2011年 | 10篇 |
2010年 | 10篇 |
2009年 | 5篇 |
2008年 | 6篇 |
2007年 | 5篇 |
2006年 | 6篇 |
2005年 | 4篇 |
2004年 | 1篇 |
2003年 | 7篇 |
2002年 | 5篇 |
2001年 | 2篇 |
2000年 | 2篇 |
1999年 | 1篇 |
1998年 | 1篇 |
1997年 | 2篇 |
1996年 | 1篇 |
1995年 | 2篇 |
1994年 | 3篇 |
1993年 | 1篇 |
1992年 | 5篇 |
1990年 | 2篇 |
1989年 | 2篇 |
1988年 | 1篇 |
1987年 | 2篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1983年 | 1篇 |
1982年 | 2篇 |
1981年 | 4篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1977年 | 1篇 |
1975年 | 1篇 |
1974年 | 1篇 |
1971年 | 1篇 |
1968年 | 1篇 |
1965年 | 2篇 |
排序方式: 共有143条查询结果,搜索用时 15 毫秒
41.
42.
We ask whether vole herbivory in experimental grassland plots is sufficient to create an unpalatable community. In a six-year experiment, meadow voles (Microtus pennsylvanicus) reduced plant standing crop between 30% and 72%, well within the range of ungulate effects. Moreover, meadow voles reduced their available forage species by changing the plant community composition: four grass species and a legume upon which they foraged declined sharply in cover and/or number of individuals, five forbs avoided by voles increased, and two forbs neither declined nor increased with either measure. Reductions of diversity occurred when voles first defoliated the plots in 2000 but disappeared as plant species avoided by voles replaced vulnerable plants. Within six years, meadow voles created plant communities dominated by species that they did not eat. 相似文献
43.
44.
The first definitive carcharodontosaurid (Dinosauria: Theropoda) from Asia and the delayed ascent of tyrannosaurids 总被引:2,自引:0,他引:2
Stephen L. Brusatte Roger B. J. Benson Daniel J. Chure Xing Xu Corwin Sullivan David W. E. Hone 《Die Naturwissenschaften》2009,96(9):1051-1058
Little is known about the evolution of large-bodied theropod dinosaurs during the Early to mid Cretaceous in Asia. Prior to
this time, Asia was home to an endemic fauna of basal tetanurans, whereas terminal Cretaceous ecosystems were dominated by
tyrannosaurids, but the intervening 60 million years left a sparse fossil record. Here, we redescribe the enigmatic large-bodied
Chilantaisaurus maortuensis from the Turonian of Inner Mongolia, China. We refer this species to a new genus, Shaochilong, and analyze its systematic affinities. Although Shaochilong has previously been allied with several disparate theropod groups (Megalosauridae, Allosauridae, Tyrannosauroidea, Maniraptora),
we find strong support for a derived carcharodontosaurid placement. As such, Shaochilong is the first unequivocal Asian member of Carcharodontosauridae, which was once thought to be restricted to Gondwana. The
discovery of an Asian carcharodontosaurid indicates that this clade was cosmopolitan in the Early to mid Cretaceous and that
Asian large-bodied theropod faunas were no longer endemic at this time. It may also suggest that the ascent of tyrannosaurids
into the large-bodied dinosaurian predator niche was a late event that occurred towards the end of the Cretaceous, between
the Turonian and the Campanian.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
45.
Shannon Sullivan Elizabeth Mccann Raymond De Young Donna Erickson 《Journal of Agricultural and Environmental Ethics》1996,9(2):123-143
Farmers have been characterized as people whose ties to the land have given them a deep awareness of natural cycles, appreciation for natural beauty and sense of responsibility as stewards. At the same time, their relationship to the land has been characterized as more utilitarian than that of others who are less directly dependent on its bounty. This paper explores this tension by comparing the attitudes and beliefs of a group of conventional farmers to those of a group of organic farmers. It was found that while both groups reject the idea that a farmer’s role is to conquer nature, organic farmers were significantly more supportive of the notion that humans should live in harmony with nature. Organic farmers also reported a greater awareness of and appreciation for nature in their relationship with the land. Both groups view independence as a main benefit of farming and a lack of financial reward as its main drawback. Overall, conventional farmers report more stress in their lives although they also view themselves in a caretaker role for the land more than do the organic farmers. In contrast, organic farmers report more satisfaction with their lives, a greater concern for living ethically, and a stronger perception of community. Finally, both groups are willing to have their rights limited (organic farmers somewhat more so) but they do not trust the government to do so. 相似文献
46.
Michael J. Manfredo Tara L. Teel Andrew W. Don Carlos Leeann Sullivan Alan D. Bright Alia M. Dietsch Jeremy Bruskotter David Fulton 《Conservation biology》2020,34(6):1549-1559
We introduced a multilevel model of value shift to describe the changing social context of wildlife conservation. Our model depicts how cultural-level processes driven by modernization (e.g., increased wealth, education, and urbanization) affect changes in individual-level cognition that prompt a shift from domination to mutualism wildlife values. Domination values promote beliefs that wildlife should be used primarily to benefit humans, whereas mutualism values adopt a view that wildlife are part of one's social network and worthy of care and compassion. Such shifts create emergent effects (e.g., new interest groups) and challenges to wildlife management organizations (e.g., increased conflict) and dramatically alter the sociopolitical context of conservation decisions. Although this model is likely applicable to many modernized countries, we tested it with data from a 2017–2018 nationwide survey (mail and email panel) of 43,949 residents in the United States. We conducted hierarchical linear modeling and correlational analysis to examine relationships. Modernization variables had strong state-level effects on domination and mutualism. Higher levels of education, income, and urbanization were associated with higher percentages of mutualists and lower percentages of traditionalists, who have strong domination values. Values affected attitudes toward wildlife management challenges; for example, states with higher proportions of mutualists were less supportive of lethal control of wolves (Canis lupus) and had lower percentages of active hunters, who represent the traditional clientele of state wildlife agencies in the United States. We contend that agencies will need to embrace new strategies to engage and represent a growing segment of the public with mutualism values. Our model merits testing for application in other countries. 相似文献
47.
What’s a Stream Without Water? Disproportionality in Headwater Regions Impacting Water Quality 总被引:1,自引:1,他引:0
Andrea Armstrong Richard C. Stedman Joseph A. Bishop Patrick J. Sullivan 《Environmental management》2012,50(5):849-860
Headwater streams are critical components of the stream network, yet landowner perceptions, attitudes, and property management behaviors surrounding these intermittent and ephemeral streams are not well understood. Our research uses the concept of watershed disproportionality, where coupled social-biophysical conditions bear a disproportionate responsibility for harmful water quality outcomes, to analyze the potential influence of riparian landowner perceptions and attitudes on water quality in headwater regions. We combine social science survey data, aerial imagery, and an analysis of spatial point processes to assess the relationship between riparian landowner perceptions and attitudes in relation to stream flow regularity. Stream flow regularity directly and positively shapes landowners’ water quality concerns, and also positively influences landowners’ attitudes of stream importance—a key determinant of water quality concern as identified in a path analysis. Similarly, riparian landowners who do not notice or perceive a stream on their property are likely located in headwater regions. Our findings indicate that landowners of headwater streams, which are critical areas for watershed-scale water quality, are less likely to manage for water quality than landowners with perennial streams in an obvious, natural channel. We discuss the relationships between streamflow and how landowners develop understandings of their stream, and relate this to the broader water quality implications of headwater stream mismanagement. 相似文献
48.
McNulty SG Cohen EC Moore Myers JA Sullivan TJ Li H 《Environmental pollution (Barking, Essex : 1987)》2007,149(3):281-292
Concern regarding the impacts of continued nitrogen and sulfur deposition on ecosystem health has prompted the development of critical acid load assessments for forest soils. A critical acid load is a quantitative estimate of exposure to one or more pollutants at or above which harmful acidification-related effects on sensitive elements of the environment occur. A pollutant load in excess of a critical acid load is termed exceedance. This study combined a simple mass balance equation with national-scale databases to estimate critical acid load and exceedance for forest soils at a 1-km(2) spatial resolution across the conterminous US. This study estimated that about 15% of US forest soils are in exceedance of their critical acid load by more than 250eqha(-1)yr(-1), including much of New England and West Virginia. Very few areas of exceedance were predicted in the western US. 相似文献
49.
J. L. Sullivan F. L. Kafka L. M. Ferrari 《Journal of the Air & Waste Management Association (1995)》2013,63(12):583-586
Though the aroma of roasting coffee can be pleasant in small amounts, large scale plants tend to cause public complaints. As a means of control thermal afterburners operating at 1200°F and higher have been commonly employed. Australian coffee consumption in the past has been relatively small but in recent years it has been increasing markedly. As a result, odor complaints have been increasing and one plant, large by Australian standards, caused a public outcry of no small order. High cost of fuel rendered thermal afterburning unattractive and, consequently, the firm in question decided upon catalytic combustion as an alternative. Subsequently, the unit was installed and before and after tests were made for various components. At an operating temperature of about 700°F the results showed comparable fume reductions to thermal afterburning and the findings were confirmed by the cessation of complaints by the public. 相似文献
50.
J. L. Sullivan R. J. Roberts 《Journal of the Air & Waste Management Association (1995)》2013,63(4):353-361
Environmental legislation is developing rapidly. In addition, considerable attention is being given to the environmental impact of new technological developments. Governments as well as citizens, often through organized groups are placing unprecedented pressures on many industries and even on other parts of the government. Popular feeling has been extremely strong on such matters and resistance so far has not been strong. This is likely to change substantially and the future may see a rapid increase in the number of environmental suits especially if the continued existence of certain industries is threatened. Expert evidence will be needed to support government legislation and to support actions to preserve the environment. Such measures will have inevitable economic implications and will evoke predictable responses. Reconciling these viewpoints will provide a challenge for the community which will probably depend to a larger extent on interpretation in courts of -law. The ability of various experts to give advice through the legal process will be essential if the most effective compromises are to be found. It is the purpose of this paper to discuss the gathering and use of such scientific evidence in environmental lawsuits. 相似文献