全文获取类型
收费全文 | 135篇 |
免费 | 0篇 |
专业分类
安全科学 | 4篇 |
废物处理 | 9篇 |
环保管理 | 14篇 |
综合类 | 8篇 |
基础理论 | 43篇 |
环境理论 | 1篇 |
污染及防治 | 38篇 |
评价与监测 | 11篇 |
社会与环境 | 7篇 |
出版年
2022年 | 3篇 |
2021年 | 2篇 |
2019年 | 2篇 |
2018年 | 4篇 |
2017年 | 3篇 |
2016年 | 2篇 |
2015年 | 1篇 |
2014年 | 4篇 |
2013年 | 2篇 |
2012年 | 9篇 |
2011年 | 9篇 |
2010年 | 15篇 |
2009年 | 3篇 |
2008年 | 5篇 |
2007年 | 8篇 |
2006年 | 4篇 |
2005年 | 3篇 |
2003年 | 8篇 |
2002年 | 6篇 |
2001年 | 2篇 |
2000年 | 4篇 |
1999年 | 2篇 |
1997年 | 2篇 |
1996年 | 1篇 |
1995年 | 2篇 |
1994年 | 4篇 |
1993年 | 4篇 |
1992年 | 2篇 |
1991年 | 2篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1988年 | 2篇 |
1987年 | 1篇 |
1986年 | 1篇 |
1984年 | 1篇 |
1983年 | 2篇 |
1982年 | 2篇 |
1980年 | 1篇 |
1974年 | 1篇 |
1972年 | 2篇 |
1956年 | 1篇 |
1926年 | 1篇 |
排序方式: 共有135条查询结果,搜索用时 15 毫秒
101.
Warfvinge P Falkengren-Grerup U Sverdrup H Andersen B 《Environmental pollution (Barking, Essex : 1987)》1993,80(3):209-221
A dynamic soil chemistry model was used to explain the observed decrease in soil base saturation between 1949 and 1984 at three stands in southern Sweden. The results show that acid deposition has caused soil acidification. The model, SAFE (Soil Acidification in Forest Ecosystems), includes the fundamental physical processes such as leaching and accumulation, and chemical processes such as cation exchange, mineral weathering, nutrient uptake and solute equilibrium reactions. The sources and sinks of base cations in the soil system were quantified, showing that weathering, deposition of base cations and depletion of exchangeable base cations supply cations to the soil solution in similar amounts in the upper 1 m during the acidification phase. This demonstrates that budget studies alone cannot be used to distinguish between long-term capacity to resist acidification, represented by weathering, from short-term buffering caused by cation exchange. 相似文献
102.
We estimated silicate uptake kinetics for 8 spring diatom species using a model based on time series measurements of the depletion
of dissolved silicate (DSi) and increases in biomass. Furthermore, the carbon: nitrogen: silicate stoichiometric relationships
and maximum growth rates were determined. Differences in DSi uptake kinetics and maximum growth rate were distinct among the
species. All the most common diatom species (Chaetoceros wighamii, Pauliella taeniata, Skeletonema costatum and Thalassiosira baltica) were relatively lightly silicified and had variable but relatively low half-saturation constants (K
s
), indicating that they are well adapted to low DSi concentrations. The less common Diatoma tenuis and Nitzschia frigida had higher K
s
values, suggesting that they are more vulnerable to DSi limitation. The much used nitrogen:silicate ratio of 1 for marine
diatom biomass was too low for most of the examined species, while a ratio of 2–3 seems to be more appropriate for these Baltic
Sea species. 相似文献
103.
Janne Flora Kasper Lambert Johansen Bjarne Grønnow Astrid Oberborbeck Andersen Anders Mosbech 《Ambio》2018,47(2):244-264
Information from a collaborative GPS tracking project, Piniariarneq, involving 17 occupational hunters from Qaanaaq and Savissivik, Northwest Greenland, is used to explore the resource spaces of hunters in Avanersuaq today. By comparison with historical records from the time of the Thule Trading Station and the decades following its closure, we reveal a marked variability in resource spaces over time. It is argued that the dynamics of resources and resource spaces in Thule are not underlain by animal distribution and migration patterns, or changes in weather and sea ice conditions alone; but also by economic opportunities, human mobility, settlement patterns, particular historical events and trajectories, and not least by economic and political interests developed outside the region. 相似文献
104.
Anette Jægerfeldt Baisner Jonas Lembcke Andersen Anders Findsen Simon Wilhelm Yde Granath Karin Ølgaard Madsen Mark Desholm 《Environmental management》2010,46(5):801-808
An increased focus on renewable energy has led to the planning and construction of marine wind farms in Europe. Since several terrestrial studies indicate that raptors are especially susceptible to wind turbine related mortality, a Spatial Planning Tool is needed so that wind farms can be sited, in an optimal way, to minimize risk of collisions. Here we use measurements of body mass, wingspan and wing area of eight European raptor species, to calculate their Best Glide Ratio (BGR). The BGR was used to construct a linear equation, which, by the use of initial take-off altitude, could be used to calculate a Theoretical Maximum Distance (TMD) from the coast, attained by these soaring-gliding raptor species. If the nearest turbine, of future marine wind farms, is placed farther away from the coast than the estimated TMD, the collision risk between the turbine blades and these gliding raptors will be minimized. The tool was demonstrated in a case study at the Rødsand II wind farm in Denmark. Data on raptor migration altitude were gathered by radar. From the TMD attained by registered soaring-gliding raptors in the area, we concluded that the Rødsand II wind farm is not sited ideally, from an ornithological point of view, as potentially all three registered species are at risk of gliding through the area swept by the turbine rotor blades, and thereby at risk of colliding with the wind turbines. 相似文献
105.
106.
Jesper H. Andersen Henrik Fossing Jens W. Hansen Ole H. Manscher Ciarán Murray Ditte L. J. Petersen 《Ambio》2014,43(7):906-913
Nutrient enrichment of coastal marine waters caused by losses of nitrate (NO3−) from agriculture is an increasing global problem. In the European Union, the Nitrates Directive (ND) of 1991 was meant to be a cornerstone in reducing eutrophication effects in coastal waters downstream from intensively farmed catchments. Although reductions in losses of nitrate have been attained, very few Member States have yet been able to reduce eutrophication effects caused by inputs of NO3− from agriculture. We report trends in concentrations of NO3− and chlorophyll-a (Chl-a) in Danish coastal and open marine waters during the period from 1996 to 2011 together with an assessment of eutrophication status based on multiple indicators (e.g. nutrient concentrations, Chl-a, submerged aquatic vegetation and benthic macroinvertebrates). Despite decreasing concentrations of both NO3−and Chl-a, Danish coastal waters are not yet to be classified as ‘unaffected by eutrophication’. In order to improve future pan-European evaluations of the effectiveness of the ND, we argue for the added value of including indicators and assessment principles from other European Directives, i.e. the Water Framework Directive and the Marine Strategy Framework Directive.
Electronic supplementary material
The online version of this article (doi:10.1007/s13280-014-0514-y) contains supplementary material, which is available to authorized users. 相似文献107.
Bacterial antibiotic resistance levels in Danish farmland as a result of treatment with pig manure slurry 总被引:17,自引:0,他引:17
Sengeløv G Agersø Y Halling-Sørensen B Baloda SB Andersen JS Jensen LB 《Environment international》2003,28(7):587-595
Resistance to tetracycline, macrolides and streptomycin was measured for a period of 8 months in soil bacteria obtained from farmland treated with pig manure slurry. This was done by spread plating bacteria on selective media (Luria Bertani (LB) medium supplemented with antibiotics). To account for seasonal variations in numbers of soil bacteria, ratios of resistant bacteria divided by total count on nonselective plates were calculated. Soil samples were collected from four different farms and from a control soil on a fifth farm. The control soil was not amended with animal manure. The occurrence of tetracycline-resistant bacteria was elevated after spread of pig manure slurry but declined throughout the sampling period to a level corresponding to the control soil. Higher load of pig manure slurry yielded higher occurrence of tetracycline resistance after spreading; however, the tetracycline resistance declined to normal occurrence defined by the tetracycline resistance occurrence in the control soil. Concentrations of tetracycline in soil and in pig manure slurry were measured using HPLC. No tetracycline exceeding the detection limit was found in soil samples. Manure slurry concentrations of tetracycline for three of the farms were 42, 81 and 698 microg/l, respectively. For streptomycin and macrolides, only minor variations in resistance levels were detected. Results obtained in this study thus indicate that tetracycline resistance levels in soil are temporarily influenced by the addition of pig manure slurry. The results indicate also that increased amount of pig manure slurry amendment may result in increased levels of tetracycline resistance in the soil. 相似文献
108.
The relationship between intermoult duration (coloration), sex, size and seasonal variations in fatty acid (FA) profiles
was studied in a population of shore crabs, Carcinus maenas, inhabiting the Isefjord, Denmark. For male shore crabs, the total hepatopancreas FA content was high in July and December
(12.7 to 16.0 mg g−1 dry weight, dw) but lower in May and September (7.3 to 10.0 mg g−1). This indicates that male shore crabs are in relatively good condition before winter, when the crabs migrate off shore,
but in relatively poor condition when they return to shallow waters during spring. The hepatopancreas FA content also decreased
over the mating season. After the mating season the hepatopancreas FA content of males had decreased to approximately 60%
of that prior to the mating season. Female shore crabs had significantly higher hepatopancreas FA levels than males in May
(11.7 mg g−1 dw), September (12.6 mg g−1 dw) and December (17.9 mg g−1 dw) but lower levels in July (9.5 mg g−1 dw). This indicates that the spawning season is the most energy-demanding part of the female reproductive cycle. For all
seasons, the hepatopancreas FA content of green shore crabs was significantly higher than that of red shore crabs. For both
colour forms, the amount of polyunsaturated fatty acids (PUFAs) was significantly higher than that of saturated fatty acids
(SAFAs) and monounsaturated fatty acids (MUFAs), with the relative proportion of PUFAs increasing when the total hepatopancreas
FA content decreased. For both genders and colour forms, the most dominating SAFA was palmitic acid (16:0). Palmitoleic acid
(16:1ω7), vaccenic acid (18:1ω7) and oleic acid (18:1ω9) were the three MUFAs found in highest concentrations. The most dominating
PUFA was eicosapentaenoic acid (EPA, 20:5ω3). Docosahexaenoic acid (DHA, 22:6ω3) and arachidonic acid (AA, 20:4ω6) were also
abundant in all samples. The results demonstrated that season, sex, size and intermoult duration all influence the amount
of FAs present in the hepatopancreas of shore crabs.
Received: 23 September 1999 / Accepted: 29 April 2000 相似文献
109.
110.
Regional Environmental Change - As the impacts of climate change (CC) have become apparent, Nepal has recently implemented a number of programs emphasizing climate sensitive resource management and... 相似文献