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881.
Background and aim Aquatic organisms of the three trophic levels (producers, consumers, reducers) have been used for a long time for ecotoxicological assessments of water quality (HABAB 2000; HABAK 1999). In biotest systems that have become established standards, algae, daphnia, and luminescent bacteria as test organisms are often used so far. However, comparative studies have shown that algae are not sufficiently sensitive to all phytotoxic agents and thus cannot be the exclusive indicator organism of any toxic effects on autotrophic life. Moreover, the EU Water Framework Directive (EU-WFD 2000) sets macrobenthos, fish, phytoplankton, and macrophytes equally side by side as indicators of the status of waters. Nevertheless, biotest systems relying on higher plants have been rarely used in assessments of aquatic sediments so far. Against this background, the aquatic duckweed test (DIN EN ISO 20079) was developed and standardized, and a sediment contact test was developed with Myriophyllum aquaticum (Feiler et al. 2004). The latter was subject of a joint research project of the German Federal Ministry of Education and Research (BMBF-Verbundprojekt “SeKT”) that examined and compared several sediment contact tests (Feiler et al. 2005). Compared to tests with algae, a biotest using macrophytes has the advantage to be more representative of higher plants, since target organism and test organism are closer related in terms of evolutionary history. The present study demonstrates that the application of biotests with higher plants in analyses of contaminated sediments yields valuable results that may contribute to a concept for the integrative assessment of water quality.  相似文献   
882.
Background Due to high safety measures in production, transport and storage of fuel oil it rarely occurs, that fuel oil will be released in the environment. One exception of this experience was the fuel oil releases of private fuel oil tanks during the “century flood” 2002 in Germany. By order of IWO (Institut für wirtschaftliche Oelheizung e.?V.), the authors investigated the environmental behaviour of fuel oil after flood incidents. Aim Due to the fast spreading of the fuel oil on water surfaces and the contamination of huge areas one expects large environmental harm. For appraisal the behaviour of fuel oil in water and soil must be studied in detail as well as the effect on high and low developed animals and plants, on water organisms and on the flora and fauna of soil. From the valuation of the environmental harm official measures and measures of precaution and safety by manufacturer and user of private fuel oil installations can be derived. Main features For considering the various aspects the authors studied the extensive analyses of the special measuring programme of Saxony-Anhalt, used interviews of concerned persons (private persons and officials), aerial photos, extensive study of literature including eco-toxicological investigations, experiences of more than 70-years applications of fuel oil in plant protection and practical experiences at large field redevelopment of oil damages following averages and accidents. The authors valuated on the base of results of analyses and on own calculations. Results The release of fuel oil in the air is no particular problem because about 40?% of the oil fast evaporate and will be decomposed to carbon dioxide and water. In addition to the evaporation a characteristic behaviour is fast spreading of the fuel oil on the water surface to very thin layers. For a typical coloured oil layer e.?g. one cubic meter of oil is spread on a water surface of about 3?km2, this corresponds to 3?ml/m2 surface and contaminates the soil after drying up with about 3?µg/kg soil some orders less than the natural content of hydrocarbons in soil. Because of the absorption capacity of soil and the microbial decomposition by everywhere existing hydrocarbons decomposing micro-organisms the oil infiltrates only a few centimetre and will be decomposed in a few months, so that ground water detriments not arise practically. By measurements a few months after fuel oil release in the flood 2002 oil components in the soil could not be detected. Discussion Acute injuries of micro-flora and -fauna in soil and water by fuel oil cannot be excluded from the first. Thus the limiting values of injuries for some water organisms are below 1?mg/l. According to the special measuring programme at the flood 2002 in Saxony-Anhalt however the measured values were mostly wide below of this limit. In detail the spreading and evaporation of fuel oil on water surfaces, the propagation and decomposition of fuel oil in soil will be described. A quantitative valuation of fuel oil distribution in a real flood incident will be given. Conclusions Particular measures of redevelopment of soil for fuel oil release after flood incidents are not necessary normally. Even at the redevelopment after transport damages or at devastated sites with essential higher oil contaminations of soil in comparison to fuel oil release after flood incidents high decomposition rates are obtained by normal soil improving measures supporting the natural micro-organisms in reducing the hydrocarbon concentration for 70–90?% after a few months. Perspectives With the described results a realistic valuation of the environmental harm of fuel oil release after flood incidents could be given. From this qualified measures can be derived for official decisions and precautionary and reliable activities at fuel oil installations of flood endangered areas.  相似文献   
883.
We investigated the impact of copepods on the seston community in a mesocosm set-up, and assessed how the changes in food quantity, quality and size affected the condition of the grazers, by measuring the RNA:DNA ratios in different developmental stages of Calanus finmarchicus. Manipulated copepod densities did not affect the particulate carbon concentration in the mesocosms. On the other hand, chlorophyll a content increased with higher copepod densities, and increasing densities had a positive effect on seston food quality in the mesocosms, measured as C:N ratios and 3:6 fatty acid ratios. These food quality indicators were significantly correlated to the nutritional status of C. finmarchicus. In contrast to our expectations, these results suggest a lower copepod growth potential on higher quality food. However, in concordance with earlier studies, we found that when copepods were in high densities the large particles (>1000 µm3) decreased and that the smaller particles (<1000 µm3) increased in number. These patterns were closely linked to the condition of C. finmarchicus, which were of better condition (RNA:DNA ratios) with increasing biovolumes of large particles, and, conversely, lower RNA:DNA ratios with increasing biovolumes of smaller particles. Consequentially, the selective grazing by copepods stimulated increased biovolumes of smaller plankton, and this increase was responsible for the increased food quality, in terms of C:N and 3:6 ratios. Thus, we conclude that the decreasing growth potentials of C. finmarchicus were a result of a decrease of favourably sized food particles, induced by copepod grazing.Communicated by O. Kinne, Oldendorf/Luhe  相似文献   
884.
Environmental and Ecological Statistics - The availability of a variety of Global Climate Models (GCMs) has increased the importance of the selection of suitable GCMs for impact assessment studies....  相似文献   
885.
Environmental Fluid Mechanics - Discharged jet from desalination plants has harmful effects on the surrounding environment so that it is essential to investigate its behavior in detail. The aim of...  相似文献   
886.
Environmental Geochemistry and Health - Biochar (BC) is a porous, carbonaceous material produced by slow pyrolysis of biomass under oxygen-limited conditions. BC production has been attracting...  相似文献   
887.
One of the most important challenges faced by business managers today is the integration of sustainability into their core functions. The contemporary enterprise is forced to leap forward from the mere adoption of green practices toward rethinking, redesigning, and redeveloping business practices in a more sustainable way. Most of the initiatives in this attempt have so far emphasized primarily the economic and environmental aspects of sustainable development and overlooked the social dimension of sustainability. As more organizations commit to sustainability, there is an increasing concern to incorporate social sustainability throughout their business operations. To conceptualize and integrate the notion, some organizations use preexisting indicators to demonstrate the value and impact of sustainability, while others look beyond the measurement of impacts by constructing their own system of indicators. This paper draws on a comprehensive literature review to determine a broadly acceptable framework of social sustainability indicators to be conceptualized and integrated into the business world. Findings suggest that economic and environmental sustainability can be driven together with core social factors including fairness and equality, poverty, health, education, delinquencies, demography, culture, and employee engagement within an organization. These results offer insight into the emerging phenomenon of formulating sustainable business strategies for organizations based on social indicators to attain the ultimate sustainable outcomes. This study is among the first to identify social sustainability indicators from societal and corporate perspectives. It offers a comprehensive social sustainability framework that may be adopted by organizations in the business world.  相似文献   
888.
889.
Background, aim, and scope Polycyclic aromatic hydrocarbons (PAH) are important environmental contaminants in the marine environment. The Baltic is known to be significantly contaminated with PAH. The eelpout (Zoarces viviparus) has been used for coastal monitoring in the Baltic. The aim of the present study was to elucidate whether the eelpout can be used to investigate PAH contamination in the Mecklenburg Bight and whether PAH sources may be revealed by the relation of the metabolites. Material and methods PAH metabolites were determined in the bile fluid of eelpout caught in spring 2008 at three sampling locations in the Wismar Bight. Two metabolites were determined by means of HPLC and fluorescence detection. In addition, bile pigments were measured photometrically. Results The concentrations of 1-hydroxypyrene in bile were significantly different at all three sampling locations under investigation. Highest concentrations were found near the city of Wismar with a mean value of 1086?ng/ml. Concentrations for individual fish ranged from <22.5 to 3317?ng/ml 1-hydroxypyrene. Concentrations of 1-hydroxyphenanthrene were lower and ranged from 2.1 to 803?ng/ml in individual samples. In fish caught next to the city of Wismar a mean value of 96?ng/ml 1-hydroxyphenanthrene was calculated. Discussion In the light of substantial anthropogenic contamination in this area caused by harbor, shipyards and shipping traffic, high values of 1-hydroxypyrene found in eelpout near the city of Wismar appear to be very plausible. Furtheron, the 1-hydroxypyrene results are in accordance to literature data. 1-Hydroxyphenantrene in eelpout bile was found in higher concentrations compared to earlier investigations. Spatial differences in the relation of the two metabolites may indicate a local source of PAH. Recommendations and perspectives PAH metabolites are useful parameters for monitoring the PAH pollution of fish like eelpout. Additional information regarding potential PAH sources can be gained from the relations of individual metabolites.  相似文献   
890.
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