全文获取类型
收费全文 | 1560篇 |
免费 | 196篇 |
国内免费 | 13篇 |
专业分类
安全科学 | 137篇 |
废物处理 | 96篇 |
环保管理 | 452篇 |
综合类 | 97篇 |
基础理论 | 582篇 |
环境理论 | 1篇 |
污染及防治 | 248篇 |
评价与监测 | 55篇 |
社会与环境 | 34篇 |
灾害及防治 | 67篇 |
出版年
2023年 | 7篇 |
2022年 | 11篇 |
2021年 | 14篇 |
2020年 | 24篇 |
2019年 | 49篇 |
2018年 | 77篇 |
2017年 | 44篇 |
2016年 | 78篇 |
2015年 | 69篇 |
2014年 | 83篇 |
2013年 | 278篇 |
2012年 | 62篇 |
2011年 | 86篇 |
2010年 | 86篇 |
2009年 | 60篇 |
2008年 | 71篇 |
2007年 | 70篇 |
2006年 | 65篇 |
2005年 | 40篇 |
2004年 | 48篇 |
2003年 | 50篇 |
2002年 | 50篇 |
2001年 | 58篇 |
2000年 | 36篇 |
1999年 | 33篇 |
1998年 | 14篇 |
1997年 | 10篇 |
1996年 | 16篇 |
1995年 | 9篇 |
1994年 | 13篇 |
1993年 | 12篇 |
1992年 | 11篇 |
1991年 | 15篇 |
1990年 | 9篇 |
1989年 | 7篇 |
1988年 | 5篇 |
1987年 | 5篇 |
1986年 | 8篇 |
1985年 | 8篇 |
1984年 | 5篇 |
1983年 | 8篇 |
1982年 | 7篇 |
1981年 | 8篇 |
1980年 | 9篇 |
1979年 | 10篇 |
1978年 | 6篇 |
1977年 | 5篇 |
1975年 | 4篇 |
1974年 | 3篇 |
1973年 | 5篇 |
排序方式: 共有1769条查询结果,搜索用时 31 毫秒
981.
982.
Jeffrey M. Levengood David J. Soucek Christopher A. Taylor David A. Gay 《Environmental monitoring and assessment》2013,185(8):6485-6494
Documenting long-term trends in mercury deposition and/or accumulation is important in setting regulatory benchmarks, modeling contaminant transfer and flux, measuring success of environmental controls, and even assigning responsibility for pollution. We conducted a study to compare mercury concentrations in small fishes from “high-mercury” and “low-mercury” regions of Illinois, as well as to examine historic patterns of mercury availability using preserved fishes. Mercury concentrations were greater in four species of small fishes collected from a stream in a “high-mercury” region than in those same taxa collected from a stream in a “low-mercury” area in Illinois. Mercury concentrations in blackstripe topminnows (Fundulus notatus) declined dramatically between 1900 and 1961/2006 in the “high-mercury” stream, presumably due reductions in mercury releases from local and regional sources. Preserved fish had an apparent increase in mercury concentrations for up to 12 months, which is consistent with changes in mass and loss of proteins observed in other studies, and we recommend that recent samples be preserved for at least 12 months before comparison with older fluid-preserved material. Based on our results, further studies of mercury in small fishes in Illinois streams appear warranted. 相似文献
983.
Norman LM Gray F Guertin DP Wissler C Bliss JD 《Environmental monitoring and assessment》2008,145(1-3):145-157
This study investigates the application of models traditionally used to estimate erosion and sediment deposition to assess the potential risk of water quality impairment resulting from metal-bearing materials related to mining and mineralization. An integrated watershed analysis using Geographic Information Systems (GIS) based tools was undertaken to examine erosion and sediment transport characteristics within the watersheds. Estimates of stream deposits of sediment from mine tailings were related to the chemistry of surface water to assess the effectiveness of the methodology to assess the risk of acid mine-drainage being dispersed downstream of abandoned tailings and waste rock piles. A watershed analysis was preformed in the Patagonia Mountains in southeastern Arizona which has seen substantial mining and where recent water quality samples have reported acidic surface waters. This research demonstrates an improvement of the ability to predict streams that are likely to have severely degraded water quality as a result of past mining activities. 相似文献
984.
Angradi TR Bolgrien DW Jicha TM Pearson MS Hill BH Taylor DL Schweiger EW Shepard L Batterman AR Moffett MF Elonen CM Anderson LE 《Environmental monitoring and assessment》2009,152(1-4):425-442
The objectives of the Environmental Monitoring and Assessment Program for Great River Ecosystems (EMAP-GRE) are to (1) develop and demonstrate, in collaboration with states, an assessment program yielding spatially unbiased estimates of the condition of mid-continent great rivers; (2) evaluate environmental indicators for assessing great rivers; and (3) assess the current condition of selected great river resources. The purpose of this paper is to describe EMAP-GRE using examples based on data collected in 2004-2006 with emphasis on an approach to determining reference conditions. EMAP-GRE includes the Upper Mississippi River, the Missouri River, and the Ohio River. Indicators include biotic assemblages (fish, macroinvertebrates, plankton, algae), water chemistry, and aquatic and riparian physical habitat. Reference strata (river reaches for which a single reference expectation is appropriate) were determined by ordination of the fish assemblage and examination of spatial variation in environmental variables. Least disturbed condition of fish assemblages for reference strata was determined by empirical modeling in which we related fish assemblage metrics to a multimetric stressor gradient. We inferred least disturbed condition from the y-intercept, the predicted condition when stress was least. Thresholds for dividing the resource into management-relevant condition classes for biotic indicators were derived using predicted least disturbed condition to set the upper bound on the least disturbed condition class. Also discussed are the outputs of EMAP-GRE, including the assessment document, multimetric indices of condition, and unbiased data supporting state and tribal Clean Water Act reporting, adaptive management, and river restoration. 相似文献
985.
One Hundred Questions of Importance to the Conservation of Global Biological Diversity 总被引:3,自引:0,他引:3
W. J. SUTHERLAND W. M. ADAMS R. B. ARONSON R. AVELING T. M. BLACKBURN S. BROAD G. CEBALLOS I. M. CÔTÉ R. M. COWLING G. A. B. DA FONSECA E. DINERSTEIN P. J. FERRARO E. FLEISHMAN C. GASCON M. HUNTER Jr. J. HUTTON P. KAREIVA A. KURIA D. W. MACDONALD K. MACKINNON F. J. MADGWICK M. B. MASCIA J. MCNEELY E. J. MILNER‐GULLAND S. MOON C. G. MORLEY S. NELSON D. OSBORN M. PAI E. C. M. PARSONS L. S. PECK H. POSSINGHAM S. V. PRIOR A. S. PULLIN M. R. W. RANDS J. RANGANATHAN K. H. REDFORD J. P. RODRIGUEZ F. SEYMOUR J. SOBEL N. S. SODHI A. STOTT K. VANCE‐BORLAND A. R. WATKINSON 《Conservation biology》2009,23(3):557-567
Abstract: We identified 100 scientific questions that, if answered, would have the greatest impact on conservation practice and policy. Representatives from 21 international organizations, regional sections and working groups of the Society for Conservation Biology, and 12 academics, from all continents except Antarctica, compiled 2291 questions of relevance to conservation of biological diversity worldwide. The questions were gathered from 761 individuals through workshops, email requests, and discussions. Voting by email to short-list questions, followed by a 2-day workshop, was used to derive the final list of 100 questions. Most of the final questions were derived through a process of modification and combination as the workshop progressed. The questions are divided into 12 sections: ecosystem functions and services, climate change, technological change, protected areas, ecosystem management and restoration, terrestrial ecosystems, marine ecosystems, freshwater ecosystems, species management, organizational systems and processes, societal context and change, and impacts of conservation interventions. We anticipate that these questions will help identify new directions for researchers and assist funders in directing funds. 相似文献
986.
Ecological effects of endocrine disruption: current evidence and research priorities. 总被引:2,自引:0,他引:2
An overview is presented of the main evidence for endocrine disruption in wildlife, focusing on reproductive effects. While there are a few clear examples of endocrine disruptive effects resulting from environmental chemical exposure, in most cases a causal link between the observed abnormalities and chemical exposure has not been established. In other cases there appears to be a link but the specific chemicals responsible for the observed effects, and the mechanisms involved, remain to be elucidated. Also it is largely unknown whether or not observed changes in individual animals lead to population-level effects. Priority research projects for the UK, ultimately aimed at determining the population-level significance of endocrine disruption, are described. 相似文献
987.
Annalies Borrel Anna Taylor Marie McGrath rew Seal Elizabeth Hormann Laura Phelps & Frances Mason 《Disasters》2001,25(2):149-163
The preparation and dissemination of policy statements are necessary but insufficient to prevent the inappropriate use of infant-feeding products in emergencies. The widespread failure of humanitarian agencies operating in the Balkan crisis to act in accordance with international policies and recommendations provides a recent example of the failure to translate infant-feeding policies into practice. This article explores the underlying reasons behind the failures which include: (1) the weak institutionalisation of policies; (2) the massive quantities of unsolicited donations of infant-feeding products: (3) the absence of monitoring systems; (4) inadequate co-ordination mechanisms; (5) the high costs of correcting mistakes; and (6) the cumulative effects of poor practice. Efforts to uphold best practice during the crisis are also documented. Finally, the article identifies actions that could be undertaken in advance of and during future emergencies to enhance the application of infant feeding policies in emergencies. 相似文献
988.
Craig L. Shafer 《Conservation biology》2001,15(2):332-344
Abstract: Modern conservation biologists may reap great insight from neglected documents prepared by field biologists of the past. Three U.S. National Park Service field biologists of the 1920s and 1930s, George Wright, Ben Thompson, and Joseph Dixon, collaborated on the first field faunal survey of U.S. national parks. The results, Fauna 1 and Fauna 2 , were published in 1933 and 1935, respectively. In addition to information about the status of park vertebrates, these monographs produced the first comprehensive list of ecologically based policies for the U.S. National Park System. They also contained precursors of many of the ideas now considered basic to conservation biology. Today's conservation biologists seem unaware of the work of these three researchers. Contemporary biologists tend to think of the key concepts in conservation biology as having developed after the 1970s, but Wright, Thompson, and Dixon expressed in rough form many of these concepts half a century before. They combined their ideas with those of their predecessors and mentors to produce an unprecedented, easy-to-understand guide on managing the biotic resources of the national parks. Despite the efforts of these pioneers, their guidance did not contribute to a significant reshaping of park management practice for at least three decades. 相似文献
989.
The Application of IUCN Red List Criteria at Regional Levels 总被引:13,自引:1,他引:12
Ulf Gärdenfors†‡§ Craig Hilton-Taylor†‡§ Georgina M. Mace†‡§ Jon Paul Rodríguez†‡§ 《Conservation biology》2001,15(5):1206-1212
This paper represents a work in progress by the World Conservation Union (IUCN). Earlier drafts of the work have appeared in IUCN publications, but the "International Issues" section of Conservation Biology seems an appropriate and important place to publish the penultimate version of the document. Comments on this issue in general or on the approach taken by the IUCN should be sent to the authors directly.
Joshua Ginsburg 相似文献
Joshua Ginsburg 相似文献
990.
Rothwell JJ Taylor KG Evans MG Allott TE 《Environmental pollution (Barking, Essex : 1987)》2011,159(10):3129-3133
Atmospheric deposition of trace metals and metalloids from anthropogenic sources has led to the contamination of many European peatlands. To assess the fate and behaviour of previously deposited arsenic and lead, we constructed catchment-scale mass budgets for a degraded peatland in Northern England. Our results show a large net export of both lead and arsenic via runoff (282 ± 21.3 gPb ha(-1) y(-1) and 60.4 ± 10.5 gAs ha(-1) y(-1)), but contrasting controls on this release. Suspended particulates account for the majority of lead export, whereas the aqueous phase dominates arsenic export. Lead release is driven by geomorphological processes and is a primary effect of erosion. Arsenic release is driven by the formation of a redox-dynamic zone in the peat associated with water table drawdown, a secondary effect of gully erosion. Degradation of peatland environments by natural and anthropogenic processes has the potential to release the accumulated pool of legacy contaminants to surface waters. 相似文献