全文获取类型
收费全文 | 5677篇 |
免费 | 49篇 |
国内免费 | 27篇 |
专业分类
安全科学 | 122篇 |
废物处理 | 282篇 |
环保管理 | 405篇 |
综合类 | 886篇 |
基础理论 | 1390篇 |
环境理论 | 5篇 |
污染及防治 | 1858篇 |
评价与监测 | 470篇 |
社会与环境 | 316篇 |
灾害及防治 | 19篇 |
出版年
2023年 | 64篇 |
2022年 | 145篇 |
2021年 | 172篇 |
2020年 | 83篇 |
2019年 | 89篇 |
2018年 | 213篇 |
2017年 | 220篇 |
2016年 | 293篇 |
2015年 | 202篇 |
2014年 | 299篇 |
2013年 | 450篇 |
2012年 | 332篇 |
2011年 | 370篇 |
2010年 | 260篇 |
2009年 | 213篇 |
2008年 | 342篇 |
2007年 | 307篇 |
2006年 | 260篇 |
2005年 | 204篇 |
2004年 | 183篇 |
2003年 | 152篇 |
2002年 | 131篇 |
2001年 | 84篇 |
2000年 | 45篇 |
1999年 | 48篇 |
1998年 | 25篇 |
1997年 | 21篇 |
1996年 | 23篇 |
1995年 | 36篇 |
1994年 | 33篇 |
1993年 | 11篇 |
1992年 | 21篇 |
1991年 | 21篇 |
1990年 | 22篇 |
1989年 | 17篇 |
1988年 | 16篇 |
1987年 | 11篇 |
1986年 | 25篇 |
1985年 | 14篇 |
1984年 | 12篇 |
1983年 | 14篇 |
1982年 | 19篇 |
1981年 | 10篇 |
1980年 | 13篇 |
1972年 | 9篇 |
1966年 | 16篇 |
1965年 | 10篇 |
1957年 | 9篇 |
1956年 | 11篇 |
1954年 | 9篇 |
排序方式: 共有5753条查询结果,搜索用时 15 毫秒
591.
Different water Acts (e.g., the European Water Framework Directive) and stakeholders involved in aquatic affairs have promoted integrated river basin management over recent decades. However, few studies have provided feedback on these policies. The aim of the current article is to fill this gap by exploring how local newspapers reflect the implementation of a broad public participation within a catchment of France known for its innovation with regard to this domain. The media coverage of a water management strategy in the Drôme watershed from 1981 to 2008 was investigated using a content analysis and a geographic information system. We sought to determine what public participation and decentralized decision-making can be in practice. The results showed that this policy was integrated because of its social perspective, the high number of involved stakeholders, the willingness to handle water issues, and the local scale suitable for participation. We emphasized the prominence of the watershed scale guaranteed by the local water authority. This area was also characterized by compromise, arrangements, and power dynamics on a fine scale. We examined the most politically engaged writings regarding water management, which topics of each group emphasized, and how the groups agreed and disagreed on issues based on their values and context. The temporal pattern of participation implementation was progressive but worked by fits and starts. 相似文献
592.
593.
594.
595.
Edouard Lavergne Isabelle Calvès Anne Leila Meistertzheim Grégory Charrier Uwe Zajonz Jean Laroche 《Marine Biology》2014,161(5):1113-1126
Temporarily open/closed estuaries (TOCEs) are major ecosystems of the Indian Ocean coastal zones. Their functioning is tightly linked to climatic events such as monsoons and storms, and their mouth can close up for prolonged and variable periods of time, thus limiting their connectivity with the marine environment. Two types of genetic markers (i.e., mitochondrial cytochrome c oxidase I (COI) gene and microsatellites) were used to assess the genetic structure of 288 individuals of Terapon jarbua, a widely distributed fish species in the wider Gulf of Aden. Firstly, the hypothesis of panmixia was tested. Then, alternative hypotheses were investigated to explain the population genetic structure of T. jarbua: could it be shaped by (1) regional biogeographic barriers (i.e., Socotra Island vs. mainland Yemen) and/or (2) the particular functioning of TOCEs in relation to the species life cycle and particular physical ocean parameters? On one hand, the polymorphism of the COI inferred (1) a high haplotype diversity and a reduced nucleotide diversity over the whole data set and (2) a “star-like” shape of the haplotype network, thus suggesting a population expansion after local extinctions during the Pleistocene glaciations. On a second hand, the genotyping of eight microsatellites showed a significant genetic differentiation between T. jarbua populations in the wider Gulf of Aden (F ST = 0.035, p < 0.01), and thus, the panmixia hypothesis was rejected. Analyses of molecular variance results did not show any significant structure between Socotra Island and mainland Yemen and thus did not support the role of biogeographic barriers in structuring T. jarbua populations. Significant multi-locus deficits in heterozygotes at particular locations displaying high levels of F IS were recorded. It was suggested that a possible Wahlund effect took place in those TOCEs which could gather several cohorts of larvae stemming from different marine subpopulations over the sampled area. The present study emphasized the uniqueness of each TOCE as a potential reservoir of biodiversity and the urgent need for a better conservation program of those estuaries in the region, in order to avoid habitat fragmentation and permanent closure of those nursery areas by human activities. 相似文献
596.
597.
598.
599.
J. Besseau-Ayasse C. Violle-Poirsier A. Bazin N. Gruchy A. Moncla F. Girard M. Till F. Mugneret A. Coussement F. Pelluard M. Jimenez P. Vago M. F. Portnoï C. Dupont C. Beneteau F. Amblard M. Valduga J. L. Bresson F. Carré-Pigeon N. Le Meur S. Tapia C. Yardin A. Receveur J. Lespinasse E. Pipiras M. P. Beaujard P. Teboul S. Brisset M. Catty E. Nowak N. Douet Guilbert H. Lallaoui S. Bouquillon V. Gatinois G. Joly-Helas F. Prieur F. Cartault D. Martin P. Kleinfinger D. Molina Gomes M. Doco-Fenzy F. Vialard 《黑龙江环境通报》2014,34(5):424-430
600.