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851.
N. Dolgener L. Freudenberger N. Schneeweiss P. L. Ibisch R. Tiedemann 《Regional Environmental Change》2014,14(3):1063-1072
Environmental change is likely to have a strong impact on biodiversity, and many species may shift their distribution in response. In this study, we aimed at projecting the availability of suitable habitat for an endangered amphibian species, the Fire-bellied toad Bombina bombina, in Brandenburg (north-eastern Germany). We modelled a potential habitat distribution map based on (1) a database with 10,581 presence records for Bombina from the years 1990 to 2009, (2) current estimates for ecogeographical variables (EGVs) and (3) the future projection of these EGVs according to the statistical regional model, respectively, the soil and water integrated model, applying the maximum entropy approach (Maxent). By comparing current and potential future distributions, we evaluated the projected change in distribution of suitable habitats and identified the environmental variables most associated with habitat suitability that turned out to be climatic variables related to the hydrological cycle. Under the applied scenario, our results indicate increasing habitat suitability in many areas and an extended range of suitable habitats. However, even if the environmental conditions in Brandenburg may change as predicted, it is questionable whether the Fire-bellied toad will truly benefit, as dispersal abilities of amphibian species are limited and strongly influenced by anthropogenic disturbances, that is, intensive agriculture, habitat destruction and fragmentation. Furthermore, agronomic pressure is likely to increase on productive areas with fertile soils and high water retention capacities, indeed those areas suitable for B. bombina. All these changes may affect temporary pond hydrology as well as the reproductive success and breeding phenology of toads. 相似文献
852.
853.
For the evaluation and monitoring of the water quality, a series of methodologies, which have as basis an ample variety of bioindicators, may be applied. The aim of this research was to evaluate the use of ecotoxicity assays with Daphnia magna and Danio rerio as alert systems in water contaminated with toxic substances. Using two toxicity databases, the sensibility of those aquatic organisms to a wide variety of chemical products and elements and to some chemical categories was investigated. The relation between the reference dose for human oral chronic exposure (RfD) of all chemical products and the acute toxicity values for both bioindicators was also studied. Acute toxicity tests with D. magna respond to a larger variety of chemicals with a higher sensitivity than those with D. rerio. Although mammals, crustaceans and fish have different routes of exposure, target organs and toxic mechanisms, acute toxicity essays with fish and Daphnia may be used as an initial screening before mammal models are used. 相似文献
854.
J. Ortega-Costa A. Lpez Garcia M. Molina Martín M.L. Guillamn Duch G. Echagüe Mndez-Vigo 《Environment international》1984,10(5-6)
The project ENMA assesses the atmospheric pollution caused by the transformation and consumption of energy. The project is in the following stages: (a) estimation of annual overall average emissions; (b) estimation of annual average concentrations of pollutants; and (c) estimation of doses. Estimation of annual overall average emissions is estimated, separately, for urban areas and point sources. Concentrations of pollutants are obtained for urban areas and point-sources by means of two different gaussian models. Finally, doses are calculated assuming that the effects of all pollutants are linear at low doses. Doses for each pollutant, and doses for exposure to several combined pollutants, are defined. The doses on population are also defined, assuming that the significance of pollution depends on the number of people exposed. 相似文献
855.
Elisa Oteros-Rozas Berta Martín-López José A. González Tobias Plieninger César A. López Carlos Montes 《Regional Environmental Change》2014,14(4):1269-1289
The ecosystem services framework is receiving increasing attention in the fields of policy and research. The assessment of human attitudes and perceptions regarding ecosystem services has been proposed as a promising tool for addressing complex problems associated with environmental change, particularly in the context of cultural landscapes. Transhumance is not only a farming practice responsible for shaping cultural landscapes but also an adaptive strategy based on mobility that may represent a useful approach to overcoming the growing challenges posed by accelerated environmental change. A socio-cultural valuation of ecosystem services associated with the Conquense Drove Road, one of the major transhumant networks still in use in Mediterranean Spain, was conducted via the distribution of questionnaires to 416 local residents and visitors to capture their perceptions regarding the importance of 34 ecosystem services (10 provisioning, 12 regulating, and 12 cultural) for both social and personal well-being. Overall, the ecosystem services considered to be the most important for social well-being were fire prevention, air purification and livestock. Most of the ecosystem services in question were perceived as declining, with the exception of those associated with recreation, scientific knowledge and environmental education. This study revealed that perceptions regarding the value of ecosystem services differed among respondents, depending on their age, place of origin and gender. Several methodological issues, as well as the implications of socio-cultural valuation for policy making, are also discussed here. 相似文献
856.
Reduced exposure to air pollution on the boardwalk in Dublin, Ireland. Measurement and prediction 总被引:1,自引:0,他引:1
This paper outlines an air pollution study carried out on Dublin city's recently completed boardwalk along the side of and overhanging the River Liffey. Air quality samples were taken along the length of the boardwalk to investigate whether pedestrians using the boardwalk would have a lower air pollution exposure than those using the adjoining footpath along the road. The results of the study show significant reductions in pedestrian exposure to both traffic derived particulates and hydrocarbons along the boardwalk as opposed to the footpath. Computational fluid dynamics was also used to model the outcome of these field measurements and shows the importance of the boundary wall between the footpath and boardwalk in reducing air pollution exposure for the pedestrian, the results of which are also presented herein. 相似文献
857.
Morphophysiological and anatomical characters of needles that are used for characterizing infraspecific taxa have been studied in Scotch pine geographic cultures established in the forest-steppe zone of Siberia. Variation in these characters has been revealed, which reflects the polymorphic structure of the species and the effect of natural selection on the composition of populations in new natural-cimatic conditions. 相似文献
858.
A. Camacho R. Devesa I. Serrano S. Blázquez L. Matia 《Journal of environmental radioactivity》2010,101(12):1048-1054
A study is presented on the distribution of 234U, 238U, 235U isotopes in surface water of the Llobregat river basin (Northeast Spain), from 2001 to 2006. Sixty-six superficial water samples were collected at 16 points distributed throughout the Llobregat river basin. Uranium isotopes were measured by alpha spectrometry (PIPS detectors). The test procedure was validated according to the quality requirements of the ISO17025 standard. The activity concentration for the total dissolved uranium ranges from 20 to 261 mBq L−1. The highest concentrations of uranium were detected in an area with formations of sedimentary rock, limestone and lignite. A high degree of radioactive disequilibrium was noted among the uranium isotopes. The 234U/238U activity ratio varied between 1.1 and 1.9 and the waters with the lowest uranium activity registered the highest level of 234U/238U activity ratio. Correlations between uranium activity in the tested water and chemical and physical characteristics of the aquifer were found. 相似文献
859.
K.L. Geisling M.K. Tashima J.R. Girman R.R. Miksch S.M. Rappaport 《Environment international》1982,8(1-6)
A passive sampling device based on the principle of diffusion has been developed for the determination of formaldehyde in ambient air. The sampler consists of a capped glass tube (with approximate dimensions of 2.4 × 9 cm) containing a glass-fiber filter treated with NaHSO3. In the field, the device collects a sample by being uncapped for a specified sampling time. After being recapped and returned to the laboratory, the filter is analyzed by the chromotropic acid (CTA) method. Laboratory validation studies were conducted by exposing the sampling devices for 1 week to dry formaldehyde gas generated by passing trioxane vapor over an acid catalyst bed. In these tests, formaldehyde concentrations ranged from 0.05 to 0.80 mL/m3. Reproducibility was excellent, with relative standard deviations averaging 5.4% for five constant concentrations. The lower detection limit was determined to be 3.6 mL/m3 h. In an occupational environment an 8-h sample would be sufficient to detect compliance with the OSHA permissible exposure limit of 3 mL/m3; in a residential environment a 1-week sample would allow detection of 0.025 mL/m3 for indoor air quality audits. 相似文献
860.
The current state of the ecology of the impact regions is outlined. It is argued that the complex of ecosystems situated around
a point polluter (an impact region) is an appropriate model for solving several fundamental and applied ecological problems
related to the exploration of strong external impacts on biota. Typical methodological errors resulting from insufficient
attention to specific features of passive experiments are analysed, and ways to avoid them are proposed. The principles of
spatial arrangements of study sites within the impact region and of the selection of experimental and evaluation units are
discussed. 相似文献