全文获取类型
收费全文 | 178篇 |
免费 | 3篇 |
国内免费 | 2篇 |
专业分类
安全科学 | 15篇 |
废物处理 | 2篇 |
环保管理 | 28篇 |
综合类 | 22篇 |
基础理论 | 67篇 |
污染及防治 | 34篇 |
评价与监测 | 4篇 |
社会与环境 | 11篇 |
出版年
2022年 | 3篇 |
2021年 | 2篇 |
2020年 | 3篇 |
2018年 | 2篇 |
2017年 | 4篇 |
2016年 | 2篇 |
2015年 | 4篇 |
2014年 | 11篇 |
2013年 | 13篇 |
2012年 | 6篇 |
2011年 | 14篇 |
2010年 | 6篇 |
2009年 | 14篇 |
2008年 | 10篇 |
2007年 | 11篇 |
2006年 | 14篇 |
2005年 | 4篇 |
2004年 | 7篇 |
2003年 | 5篇 |
2002年 | 5篇 |
2001年 | 5篇 |
2000年 | 4篇 |
1999年 | 3篇 |
1998年 | 6篇 |
1997年 | 1篇 |
1995年 | 3篇 |
1993年 | 1篇 |
1992年 | 3篇 |
1990年 | 1篇 |
1989年 | 2篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1981年 | 1篇 |
1979年 | 3篇 |
1978年 | 2篇 |
1977年 | 1篇 |
1976年 | 1篇 |
1965年 | 1篇 |
1954年 | 1篇 |
1932年 | 1篇 |
排序方式: 共有183条查询结果,搜索用时 15 毫秒
101.
102.
Alexandra Baeta Ivan Valiela Francesca Rossi Rute Pinto Pierre Richard Nathalie Niquil João C. Marques 《Marine Biology》2009,156(10):2107-2120
In estuaries, eelgrass meadows contribute to fundamental ecosystem functions of estuaries, providing food to several predators
and buffering the negative effects of eutrophication. We asked whether the presence of the eelgrass Zostera noltii decreased the nitrogen concentration in the overlying water, affected the sources of nitrogen sequestrated by primary producers
and changed the benthic and pelagic food web structures. We also studied the importance of these food webs in providing food
to fish. We compared bare sediment to sediment covered by a Z. noltii meadow, and examined nutrient concentrations in the water column and δ15N in primary producers as indicators of anthropogenic inputs of nutrients. We then measured both δ13C and δ15N in the tissues of plants and consumers to establish food web structures. There were no differences in the concentrations
and sources of nitrogen between sites. Rather, δ15N values indicated anthropogenic inputs of N (e.g. sewage discharges, agriculture) in both sites. There were no major differences
in the structure of the planktonic food web, which was in part sustained by particulate organic matter and supported most
predator fish, and in the structure of the benthic food web. Nonetheless, there were differences in the sources of food for
omnivore consumers and for the detritivore Scrobicularia plana. Overall, the benthic food web did not use food derived from the eelgrass or macroalgae deposited on the substratum. Suspension
feeders used particulate and sediment organic matter, whereas the δ13C and δ15N values of the other consumers indicated a likely contribution of benthic microalgae. Furthermore, in both habitats we found
large variability in the isotope signatures of benthic macrofauna consumers, which did not allow distinguishing clearly different
trophic groups and indicated a high level of omnivory and a mixed diet opportunistically making use of the availability of
food in the surroundings. 相似文献
103.
Salminen JM Hänninen PJ Leveinen J Lintinen PT Jørgensen KS 《Journal of environmental quality》2006,35(6):2273-2282
The occurrence and rates of terminal electron acceptor processes, and recharge processes in the unsaturated zone of a boreal site contaminated with petroleum hydrocarbons in the range C(10) to C(40) were examined. Soil microcosms were used to determine the rates of denitrification, iron (Fe) reduction, sulfate (SO(4)) reduction, and methanogenesis in two vertical soil profiles contaminated with oil, and in a noncontaminated reference sample. Furthermore, the abundances of the 16S rRNA genes belonging to Geobacteracaea in the samples were determined by real-time quantitative polymerase chain reaction (PCR). Analyses of ground water chemistry and soil gas composition were also performed together with continuous in situ monitoring of soil water and ground water chemistry. Several lines of evidence were obtained to demonstrate that both Fe reduction and methanogenesis played significant roles in the vertical profiles: Fe reduction rates up to 3.7 nmol h(-1) g(-1) were recorded and they correlated with the abundances of the Geobacteracaea 16S rRNA genes (range: 2.3 x 10(5) to 4.9 x 10(7) copies g(-1)). In the ground water, ferrous iron (Fe(2+)) concentration up to 55 mg L(-1) was measured. Methane production rates up to 2.5 nmol h(-1) g(-1) were obtained together with methane content up to 15% (vol/vol) in the soil gas. The continuous monitoring of soil water and ground water chemistry, microcosm experiments, and soil gas monitoring together demonstrated that the high microbial activity in the unsaturated zone resulted in rapid removal of oxygen from the infiltrating recharge thus leaving the anaerobic microbial processes dominant below 1.5 m depth both in the unsaturated and the saturated zones of the subsurface. 相似文献
104.
Environmental Security: A Geographic Information System Analysis Approach—The Case of Kenya 总被引:2,自引:0,他引:2
Studies into the relationships between environmental factors and violence or conflicts constitute a very debated research
field called environmental security. Several authors think that environmental scarcity, which is scarcity of renewable resources,
can contribute to generate violence or social unrest, particularly within states scarcely endowed with technical know-how
and social structures, such as developing countries. In this work, we referred to the theoretical model developed by the Environmental
Change and Acute Conflict Project. Our goal was to use easily available spatial databases to map the various sources of environmental
scarcity through geographic information systems, in order to locate the areas apparently most at risk of suffering negative
social effects and their consequences in terms of internal security. The analysis was carried out at a subnational level and
applied to the case of Kenya. A first phase of the work included a careful selection of databases relative to renewable resources.
Spatial operations among these data allowed us to obtain new information on the availability of renewable resources (cropland,
forests, water), on the present and foreseen demographic pressure, as well as on the social and technical ingenuity. The results
made it possible to identify areas suffering from scarcity of one or more renewable resources, indicating different levels
of gravity. Accounts from Kenya seem to confirm our results, reporting clashes between tribal groups over the access to scarce
resources in areas that our work showed to be at high risk. 相似文献
105.
Anu Lokkiluoto Pekka A. Taskinen Michael Gasik Ilkka V. Kojo Helj? Peltola Michael H. Barker Karl-Heinz Kleifges 《Environment, Development and Sustainability》2012,14(4):529-540
Outotec open cycle (OOC) is a new low-energy process linking together production of hydrogen and sulfuric acid. While sulfuric acid is the world’s most widely produced chemical by mass at approximately 200 Mt/a, the OOC gives the potential for making 4 Mt/a of hydrogen gas as a by-product. H2SO4 manufacture requires a source of sulfur dioxide. 30% of world production of H2SO4 is from the SO2 by-product of pyrometallurgical processing of sulfur containing concentrates of metals such as copper, nickel and zinc. SO2 can also be made by direct combustion of sulfur. In OOC, a divided electrochemical cell is used for SO2-depolarized electrolysis of water. SO2 is fed to the anolyte and converted to H2SO4, while hydrogen gas is produced at the cathode. On the industrial scale, the equipment will be in the form of a membrane electrolyzer assembly or stack. A case is described where the OOC would be connected to a pyrometallurgical plant smelting 1 Mt/a of nickel and copper concentrate, producing 1 Mt/a of H2SO4 and 20 kt/a of hydrogen. 相似文献
106.
107.
Isosaari P Hallikainen A Kiviranta H Vuorinen PJ Parmanne R Koistinen J Vartiainen T 《Environmental pollution (Barking, Essex : 1987)》2006,141(2):213-225
A total of 156 fish composite samples were collected from five areas of the Baltic Sea and from three lakes and analysed for polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs), polychlorinated naphthalenes (PCNs) and polybrominated diphenyl ethers (PBDEs). The European Union's maximum permissible level for PCDD/Fs, 4 pg WHO-TEQ/g fresh weight (fw), was exceeded in salmon, river lamprey and Baltic herring. In other species from the Baltic Sea, the 90th percentile was 3.42 pg WHO(PCDD/F)-TEQ/g fw. In the lake fish, the concentrations of PCDD/Fs, PCBs and PCNs were only 29-46% of those in the same species caught from the Baltic Sea, whereas the concentrations of PBDEs in the lake fish were as high as in the Baltic Sea fish. Dioxin-like PCBs contributed to the total dioxin-like toxicity of PCBs and PCDD/Fs by 49+/-12% in all the analysed samples. 相似文献
108.
Györgyi Bela Taru Peltola Juliette C. Young Bálint Balázs Isabelle Arpin György Pataki Jennifer Hauck Eszter Kelemen Leena Kopperoinen Ann Van Herzele Hans Keune Susanne Hecker Monika Suškevičs Helen E. Roy Pekka Itkonen Mart Külvik Miklós László Corina Basnou Joan Pino Aletta Bonn 《Conservation biology》2016,30(5):990-999
The number of collaborative initiatives between scientists and volunteers (i.e., citizen science) is increasing across many research fields. The promise of societal transformation together with scientific breakthroughs contributes to the current popularity of citizen science (CS) in the policy domain. We examined the transformative capacity of citizen science in particular learning through environmental CS as conservation tool. We reviewed the CS and social‐learning literature and examined 14 conservation projects across Europe that involved collaborative CS. We also developed a template that can be used to explore learning arrangements (i.e., learning events and materials) in CS projects and to explain how the desired outcomes can be achieved through CS learning. We found that recent studies aiming to define CS for analytical purposes often fail to improve the conceptual clarity of CS; CS programs may have transformative potential, especially for the development of individual skills, but such transformation is not necessarily occurring at the organizational and institutional levels; empirical evidence on simple learning outcomes, but the assertion of transformative effects of CS learning is often based on assumptions rather than empirical observation; and it is unanimous that learning in CS is considered important, but in practice it often goes unreported or unevaluated. In conclusion, we point to the need for reliable and transparent measurement of transformative effects for democratization of knowledge production. 相似文献
109.
Antonio Proto Raffaele Cucciniello Federico Rossi Oriana Motta 《Environmental science and pollution research international》2014,21(4):3182-3186
In this paper, stable carbon isotope ratios (δ 13C) were determined in the atmosphere by using a Ca-based sorbent, CaO/Ca12Al14O33 75:25 w/w, for passively collecting atmospheric CO2, in both field and laboratory experiments. Field measurements were conducted in three environments characterized by different carbon dioxide sources. In particular, the environments under consideration were a rather heavily trafficked road, where the source of CO2 is mostly vehicle exhaust, a rural unpolluted area, and a private kitchen where the major source of CO2 was gas combustion. Samplers were exposed to the free atmosphere for 3 days in order to allow collection of sufficient CO2 for δ13C analysis, then the collected CO2 was desorbed from the adsorbent with acid treatment, and directly analyzed by nondispersive infrared (NDIR) instrument. δ 13C results confirmed that the samplers collected representative CO2 samples and no fractionation occurred during passive trapping, as also confirmed by an appositely designed experiment conducted in the laboratory. Passive sampling using CaO/Ca12Al14O33 75:25 w/w proved to be an easy and reliable method to collect atmospheric carbon dioxide for δ 13C analysis in both indoor and outdoor places. 相似文献
110.
Towards more non-compensatory sustainable society index 总被引:1,自引:0,他引:1