全文获取类型
收费全文 | 11291篇 |
免费 | 28篇 |
国内免费 | 15篇 |
专业分类
安全科学 | 54篇 |
废物处理 | 826篇 |
环保管理 | 1500篇 |
综合类 | 1209篇 |
基础理论 | 3474篇 |
环境理论 | 4篇 |
污染及防治 | 2162篇 |
评价与监测 | 1125篇 |
社会与环境 | 975篇 |
灾害及防治 | 5篇 |
出版年
2023年 | 20篇 |
2022年 | 20篇 |
2021年 | 25篇 |
2020年 | 24篇 |
2019年 | 25篇 |
2018年 | 1491篇 |
2017年 | 1399篇 |
2016年 | 1222篇 |
2015年 | 167篇 |
2014年 | 63篇 |
2013年 | 132篇 |
2012年 | 526篇 |
2011年 | 1426篇 |
2010年 | 761篇 |
2009年 | 679篇 |
2008年 | 953篇 |
2007年 | 1312篇 |
2006年 | 86篇 |
2005年 | 91篇 |
2004年 | 105篇 |
2003年 | 128篇 |
2002年 | 172篇 |
2001年 | 47篇 |
2000年 | 36篇 |
1999年 | 20篇 |
1998年 | 28篇 |
1997年 | 23篇 |
1996年 | 18篇 |
1995年 | 23篇 |
1994年 | 25篇 |
1993年 | 13篇 |
1992年 | 16篇 |
1991年 | 15篇 |
1990年 | 12篇 |
1989年 | 12篇 |
1988年 | 17篇 |
1987年 | 12篇 |
1986年 | 15篇 |
1984年 | 19篇 |
1983年 | 18篇 |
1982年 | 11篇 |
1981年 | 9篇 |
1980年 | 7篇 |
1979年 | 10篇 |
1978年 | 7篇 |
1977年 | 5篇 |
1976年 | 7篇 |
1974年 | 6篇 |
1955年 | 5篇 |
1954年 | 8篇 |
排序方式: 共有10000条查询结果,搜索用时 750 毫秒
731.
Supply of international environmental public goods must meet certain conditions to be socially efficient, and several reasons
explain why they are currently undersupplied. Diagnosis of the public goods failure associated with particular ecosystem services
is critical to the development of the appropriate international response. There are two categories of international environmental
public goods that are most likely to be undersupplied. One has an additive supply technology and the other has a weakest link
supply technology. The degree to which the collective response should be targeted depends on the importance of supply from
any one country. In principle, the solution for the undersupply lies in payments designed to compensate local providers for
the additional costs they incur in meeting global demand. Targeted support may take the form of direct investment in supply
(the Global Environment Facility model) or of payments for the benefits of supply (the Payments for Ecosystem Services model). 相似文献
732.
Rundqvist S Hedenås H Sandström A Emanuelsson U Eriksson H Jonasson C Callaghan TV 《Ambio》2011,40(6):683-692
Shrubs and trees are expected to expand in the sub-Arctic due to global warming. Our study was conducted in Abisko, sub-arctic
Sweden. We recorded the change in coverage of shrub and tree species over a 32– to 34-year period, in three 50 × 50 m plots;
in the alpine-tree-line ecotone. The cover of shrubs and trees (<3.5 cm diameter at breast height) were estimated during 2009–2010
and compared with historical documentation from 1976 to 1977. Similarly, all tree stems (≥3.5 cm) were noted and positions
determined. There has been a substantial increase of cover of shrubs and trees, particularly dwarf birch (Betula nana), and mountain birch (Betula pubescens ssp. czerepanovii), and an establishment of aspen (Populus tremula). The other species willows (Salix spp.), juniper (Juniperus communis), and rowan (Sorbus aucuparia) revealed inconsistent changes among the plots. Although this study was unable to identify the causes for the change in shrubs
and small trees, they are consistent with anticipated changes due to climate change and reduced herbivory. 相似文献
733.
This study was conducted in the Swedish sub-Arctic, near Abisko, in order to assess the direction and scale of possible vegetation
changes in the alpine–birch forest ecotone. We have re-surveyed shrub, tree and vegetation data at 549 plots grouped into
61 clusters. The plots were originally surveyed in 1997 and re-surveyed in 2010. Our study is unique for the area as we have
quantitatively estimated a 19% increase in tree biomass mainly within the existing birch forest. We also found significant
increases in the cover of two vegetation types—“birch forest-heath with mosses” and “meadow with low herbs”, while the cover
of snowbed vegetation decreased significantly. The vegetation changes might be caused by climate, herbivory and past human
impact but irrespective of the causes, the observed transition of the vegetation will have substantial effects on the mountain
ecosystems. 相似文献
734.
735.
Floodplain soils containing elevated levels of polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs) were collected from several locations along the Tittabawassee River (Michigan, USA). The PCDD/F profiles of these soils exhibited distinct congener patterns consistent with byproducts from either chloralkali manufacturing or chlorophenols productions. Black carbon (BC) particles were isolated for the first time from floodplain soil impacted by PCDD/Fs. Petrographic analysis showed that BC particles, including coal, oxidized coal, metallurgical coke, depositional carbon, coal tar/pitch, cenosphere, and charcoal, comprised approximately 30% by volume of the organic fraction with size range of 250 μm-2000 μm from a typical floodplain soil. The BC particles with anthropogenic origin such as pitch and coke associated with the chloralkali production process served as both the source and subsequent transporter for the highly hydrophobic PCDD/Fs. These anthropogenic BC particles were enriched with high levels of PCDFs, containing approximately 1000-fold the concentration found in the bulk soil. The strong association of PCDD/Fs with anthropogenic BC directly impacts the physicochemical and biological availability thus the risk associated with these hydrophobic organochlorines in soils and sediments. 相似文献
736.
Kabiersch G Rajasärkkä J Ullrich R Tuomela M Hofrichter M Virta M Hatakka A Steffen K 《Chemosphere》2011,83(3):226-232
Bisphenol A is an endocrine disrupting compound, which is ubiquitous in the environment due to its wide use in plastic and resin production. Seven day old cultures of the litter-decomposing fungus Stropharia coronilla removed the estrogenic activity of bisphenol A (BPA) rapidly and enduringly. Treatment of BPA with purified neutral manganese peroxidase (MnP) from this fungus also resulted in 100% reduction of estrogenic activity, as analyzed using a bioluminescent yeast assay, and in the formation of polymeric compounds. In cultures of Stropharia rugosoannulata, estrogenic activity also quickly disappeared but temporarily re-emerged in the further course of cultivation. LC-MS analysis of the extracted estrogenic culture liquid revealed [M−H]− ions with m/z values of 219 and 235. We hypothesize that these compounds are ring fission products of BPA, which still exhibit one intact hydroxyphenyl group to interact with estrogen receptors displayed by the yeast. 相似文献
737.
Müller CE Gerecke AC Alder AC Scheringer M Hungerbühler K 《Environmental pollution (Barking, Essex : 1987)》2011,159(5):1419-1426
Anthropogenic perfluorinated compounds (PFCs), especially the perfluoroalkyl acids (PFAAs) are ubiquitously found in surface waters around the globe. Emissions from households, industries and also atmospheric transport/deposition are discussed as the possible sources. In this study, these sources are evaluated using Switzerland as the study area. Forty-four surface water locations in different rivers and an Alpine lake were investigated for 14 PFAAs, four precursors and acesulfame, an artificial sweetener used as a population marker. Concentrations of individual PFAAs were generally low, between 0.02 and 10 ng/L. Correlation analysis showed that some PFAAs concentrations correlated well with population and less with catchment area, indicating that emissions from population, i.e., from consumer products, is the most important source to surface waters in Switzerland. The correlation with the population marker acesulfame confirmed this observation but highlighted also a few elevated PFAA levels, some of which could be attributed to industrial emissions. 相似文献
738.
Langner M Kull M Endlicher WR 《Environmental pollution (Barking, Essex : 1987)》2011,159(8-9):2028-2034
Deposition of PM(10) particles to several types of urban surfaces was investigated within this study. Antimony was chosen as a tracer element to calculate dry deposition velocities for PM(10), since antimony proved to be present almost exclusively in PM(10) particles in ambient urban air. During 18 months, eight sampling sites in Berlin and Karlsruhe, two cities in Germany, were operated. PM(10) concentrations and dry deposition were routinely sampled as two week averages. Additionally, leaf-samples were collected at three sites with tall vegetation. The obtained deposition velocities ranged from 0.8 to 1.3 cms(-1) at roadside sites and from 0.4 to 0.5 cms(-1) at the other sites. With reference to the whole canopy, additional deposition velocities of about 0.5 cms(-1) were obtained for leaf surfaces. As a consequence, it can be concluded that vegetation-covered areas beside streets show the highest potential to capture particles in urban areas. 相似文献
739.
Kacániová M Fatrcová-Sramková K Nozková J Melich M Kadasi-Horáková M Knazovická V Felsöciová S Kunová S Máriássyová M 《Journal of environmental science and health. Part. B》2011,46(1):92-96
The purpose of the study was to examine the antiradical activity of 11 natural honeys and to evaluate the antifungal properties of honey. Honey samples (10) were collected from different locations of Slovak Republic. Honeys were native to different plant species of Robinia pseudoacaccia, Brassica napus subs. napus, Castanea sativa Mill. Thymus serpyllum vulgaris and the other samples had multifloral origin. The low antiradical activitity in honey samples was determined. The best results were found in thyme honey from Rhodos (11.84 %) and Castanea honey from Nitra (10.61 %). The lowest antiradical activity was found in Acacia honey and determined to be 7.62 %. Statistically significant differences (P< 0.001) were found among thyme/Rhodos and Castanea/Nitra. The antifungal activities of honey samples were tested by 10 %, 25 % and 50 % (by mass per volume) concentration against fungi Penicillium crustosum, P. expansum, P. griseofulvum, P. raistrickii and P. verrucosum and by the agar well diffusion method. The solutions containing 10 % (by mass per volume) of honey did not have any effect on the growth of fungi. The strongest antifungal effect was shown by 50 % honey concentration against P. raistrickii. 相似文献
740.
Giloteaux L Solé A Esteve I Duran R 《Environmental science and pollution research international》2011,18(7):1147-1159