全文获取类型
收费全文 | 27609篇 |
免费 | 226篇 |
国内免费 | 152篇 |
专业分类
安全科学 | 598篇 |
废物处理 | 1462篇 |
环保管理 | 3844篇 |
综合类 | 4243篇 |
基础理论 | 7503篇 |
环境理论 | 14篇 |
污染及防治 | 6189篇 |
评价与监测 | 2112篇 |
社会与环境 | 1881篇 |
灾害及防治 | 141篇 |
出版年
2022年 | 151篇 |
2021年 | 149篇 |
2020年 | 127篇 |
2019年 | 161篇 |
2018年 | 1670篇 |
2017年 | 1583篇 |
2016年 | 1547篇 |
2015年 | 445篇 |
2014年 | 458篇 |
2013年 | 1578篇 |
2012年 | 1028篇 |
2011年 | 2042篇 |
2010年 | 1267篇 |
2009年 | 1205篇 |
2008年 | 1580篇 |
2007年 | 1963篇 |
2006年 | 754篇 |
2005年 | 616篇 |
2004年 | 608篇 |
2003年 | 655篇 |
2002年 | 610篇 |
2001年 | 615篇 |
2000年 | 468篇 |
1999年 | 291篇 |
1998年 | 245篇 |
1997年 | 231篇 |
1996年 | 245篇 |
1995年 | 254篇 |
1994年 | 246篇 |
1993年 | 232篇 |
1992年 | 247篇 |
1991年 | 227篇 |
1990年 | 229篇 |
1989年 | 191篇 |
1988年 | 163篇 |
1987年 | 150篇 |
1986年 | 179篇 |
1985年 | 171篇 |
1984年 | 189篇 |
1983年 | 192篇 |
1982年 | 184篇 |
1981年 | 184篇 |
1980年 | 169篇 |
1979年 | 161篇 |
1978年 | 111篇 |
1977年 | 130篇 |
1974年 | 117篇 |
1973年 | 92篇 |
1972年 | 109篇 |
1971年 | 97篇 |
排序方式: 共有10000条查询结果,搜索用时 359 毫秒
641.
Salinity levels vary spatially in coastal areas, depending on proximity to freshwater sources, and may also be slowly decreasing
as a result of anthropogenic climatic changes. The impact of salinity on host–parasite interactions is potentially a key regulator
of transmission processes in intertidal areas, where trematodes are extremely common parasites of invertebrates and vertebrates.
We investigated experimentally the effects of long-term exposure to decreased salinity levels on output of infective stages
(cercariae) and their transmission success in the trematode Philophthalmus sp. This parasite uses the snail Zeacumantus subcarinatus as intermediate host, in which it asexually produces cercariae. After leaving the snail, cercariae encyst externally on hard
substrates to await accidental ingestion by shorebirds, which serve as definitive hosts. We found that at reduced salinities
(25 or 30 psu), the cercarial output of the parasite was lower, the time taken by cercariae to encyst was longer, fewer cercariae
successfully encysted and encysted parasites had lower long-term survival than at normal seawater salinity (35 psu). The strong
effect of salinity on the replication and transmission of this parasite suggests that there may be sources and sinks of transmission
to birds along coastal areas, depending on local salinity conditions. Also, unless it evolves to adapt to changing conditions,
the predicted reduction in salinity as a consequence of climate change may have negative impact on the parasite’s abundance. 相似文献
642.
Loss of zooxanthellae (dinoflagellate Symbiodinium) from corals will sometimes lead to mass mortality of corals. To detect and quantify Symbiodinium released from corals, we developed a zooxanthellae “trap” and a quantitative PCR (qPCR) system with Symbiodinium clades A–F-specific primer sets. The trap was attached to a branch or the surface of several wild stony corals, and the water
samples within the traps, including released Symbiodinium, were subjected to qPCR. All tested corals released clade C Symbiodinium at estimates of ~5,900 cells h−1 cm−2 of coral surface. Although all tested Pocillopora eydouxi harboured both clades C and D, some of these colonies released only clade C or released a lesser amount of clade D than that
in the tissues. Our Symbiodinium quantification system revealed that wild hermatypic corals constantly release Symbiodinium to the environment. Our result suggests that some corals may discharge certain clades of Symbiodinium alternatively. 相似文献
643.
644.
645.
Gene E. Likens 《Ambio》2021,50(2):278
Early studies published in Ambio showed large-scale acidification of lakes in southern Sweden and Norway from acid rain. These studies were important for delimiting various scientific issues and thus for eventually contributing to legislation, which reduced emissions of sulfur dioxide and nitrogen oxides and helped to mitigate this major environmental problem. Long-term studies and monitoring in Sweden and Norway and at Hubbard Brook Experimental Forest in New Hampshire helped guide this legislation in Europe and in the USA. 相似文献
646.
Brian E. Reichert Mylea Bayless Tina L. Cheng Jeremy T. H. Coleman Charles M. Francis Winifred F. Frick Benjamin S. Gotthold Kathryn M. Irvine Cori Lausen Han Li Susan C. Loeb Jonathan D. Reichard Thomas J. Rodhouse Jordi L. Segers Jeremy L. Siemers Wayne E. Thogmartin Theodore J. Weller 《Ambio》2021,50(4):901
Collaborative monitoring over broad scales and levels of ecological organization can inform conservation efforts necessary to address the contemporary biodiversity crisis. An important challenge to collaborative monitoring is motivating local engagement with enough buy-in from stakeholders while providing adequate top-down direction for scientific rigor, quality control, and coordination. Collaborative monitoring must reconcile this inherent tension between top-down control and bottom-up engagement. Highly mobile and cryptic taxa, such as bats, present a particularly acute challenge. Given their scale of movement, complex life histories, and rapidly expanding threats, understanding population trends of bats requires coordinated broad-scale collaborative monitoring. The North American Bat Monitoring Program (NABat) reconciles top-down, bottom-up tension with a hierarchical master sample survey design, integrated data analysis, dynamic data curation, regional monitoring hubs, and knowledge delivery through web-based infrastructure. NABat supports collaborative monitoring across spatial and organizational scales and the full annual lifecycle of bats. 相似文献
647.
648.
Innovative aspects of environmental chemistry and technology regarding air,water, and soil pollution
Katsoyiannis Ioannis A. Lammel Gerhard Samara Constantini Ernst Mathias Wenk Jannis Torretta Vincenzo Voutsa Dimitra Vollertsen Jes Bucheli Thomas D. Godbersen Levke Lambropoulou Dimitra Heath Ester Kallenborn Roland Giannakoudakis Dimitrios Deliyanni Eleni Bandosz Teresa J. Ražić Slavica Samanidou Viktoria Papa Ester Lacorte Silvia Katsoyiannis Athanasios 《Environmental science and pollution research international》2021,28(42):58958-58968
Environmental Science and Pollution Research - 相似文献
649.
Kumar Jebarathnam Prince Prakash Jeba Ragumaran Shunmugavel Nandagopal Ganesan Ravichandran Vijaya Mallavarapu Ramana Murthy Missimer Thomas M. 《Environmental science and pollution research international》2021,28(5):5116-5125
Environmental Science and Pollution Research - Marine and freshwater pollution caused by transport of invasive species in shipping ballast water is a major global problem and will increase in... 相似文献
650.
Laffont Laure Menges Johanna Goix Sylvaine Gentès Sophie Maury-Brachet Régine Sonke Jeroen E. Legeay Alexia Gonzalez Patrice Rinaldo Raphaëlle Maurice Laurence 《Environmental science and pollution research international》2021,28(43):60609-60621
Environmental Science and Pollution Research - The aim of the study was to determine if gold-mining activities could impact the mercury (Hg) concentrations and isotopic signatures in freshwater... 相似文献