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141.
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143.
Assigning money amounts to represent intrinsic value of precious eco-systems in developing countries
Harvey F. Ludwig 《The Environmentalist》2006,26(3):143-145
Conclusion The need is urgent, if the ongoing rapid degradation of the remaining precious eco-systems of the developing countries are
to be put under control while there is still time, for developing a procedure by which the real world intrinsic meaningfulness
to people of precious eco-systems is recognized by assigning them monetary values to be considered in benefit/cost analyses.
The procedures recommended by the U.S. Corps of Engineers and Resources of the Future for use in the USA seem to be much too
complex for application in developing countries in the foreseeable future. Rather a very pragmatic approach is recommended
based on actual experience in money outlays for such protection in USA projects, with the amounts modified to suit developing
country conditions. Hopefully the IAAs (Multilateral Development Banks, Bilaterials, U.N. Agencies) will carry out the recommended
R&D studies to produce a prescribed methodology recognized by economic, environmental, and political decision makers of both
the IAAs and the DCs to be appropriate for use in planning and evaluating DC projects. 相似文献
144.
Beyene A Kassahun Y Addis T Assefa F Amsalu A Legesse W Kloos H Triest L 《Environmental monitoring and assessment》2012,184(11):7053-7063
Although waste from coffee processing is a valuable resource to make biogas, compost, and nutrient-rich animal food, it is usually dumped into nearby water courses. We carried out water quality assessment at 44 sampling sites along 18 rivers that receive untreated waste from 23 coffee pulping and processing plants in Jimma Zone, Ethiopia. Twenty upstream sampling sites free from coffee waste impact served as control, and 24 downstream sampling sites affected by coffee waste were selected for comparison. Physicochemical and biological results revealed a significant river water quality deterioration as a result of disposing untreated coffee waste into running water courses. During coffee-processing (wet) season, the highest organic load (1,900?mg/l), measured as biochemical oxygen demand, depleted dissolved oxygen (DO) to a level less than 0.01?mg/l, and thus curtailed nitrification. During off season, oxygen started to recuperate and augmented nitrification. The shift from significantly elevated organic load and reduced DO in the wet season to increased nitrate in the off season was found to be the determining factor for the difference in macroinvertebrate community structure as verified by ordination analysis. Macroinvertebrate diversity was significantly reduced in impacted sites during the wet season contrary to the off season. However, there was a significant difference in the ratio of sensitive to pollution-tolerant taxa in the off season, which remained depreciated in the longer term. This study highlights the urgency of research exploring on the feasibility of adopting appropriate pollution abatement technologies to implement ecologically sound coffee-processing systems in coffee-growing regions of Ethiopia. 相似文献
145.
Buczko U Kuchenbuch RO Ubelhör W Nätscher L 《Environmental monitoring and assessment》2012,184(7):4517-4538
Assessment of trace element contents in soils is required in Germany (and other countries) before sewage sludge application on arable soils. The reliability of measured element contents is affected by measurement uncertainty, which consists of components due to (1) sampling, (2) laboratory repeatability (intra-lab) and (3) reproducibility (between-lab). A complete characterization of average trace element contents in field soils should encompass the uncertainty of all these components. The objectives of this study were to elucidate the magnitude and relative proportions of uncertainty components for the metals As, B, Cd, Co, Cr, Mo, Ni, Pb, Tl and Zn in three arable fields of different field-scale heterogeneity, based on a collaborative trial (CT) (standardized procedure) and two sampling proficiency tests (PT) (individual sampling procedure). To obtain reference values and estimates of field-scale heterogeneity, a detailed reference sampling was conducted. Components of uncertainty (sampling person, sampling repetition, laboratory) were estimated by variance component analysis, whereas reproducibility uncertainty was estimated using results from numerous laboratory proficiency tests. Sampling uncertainty in general increased with field-scale heterogeneity; however, total uncertainty was mostly dominated by (total) laboratory uncertainty. Reproducibility analytical uncertainty was on average by a factor of about 3 higher than repeatability uncertainty. Therefore, analysis within one single laboratory and, for heterogeneous fields, a reduction of sampling uncertainty (for instance by larger numbers of sample increments and/or a denser coverage of the field area) would be most effective to reduce total uncertainty. On the other hand, when only intra-laboratory analytical uncertainty was considered, total sampling uncertainty on average prevailed over analytical uncertainty by a factor of 2. Both sampling and laboratory repeatability uncertainty were highly variable depending not only on the analyte but also on the field and the sampling trial. Comparison of PT with CT sampling suggests that standardization of sampling protocols reduces sampling uncertainty, especially for fields of low heterogeneity. 相似文献
146.
Peretyatko A Teissier S De Backer S Triest L 《Environmental monitoring and assessment》2012,184(3):1517-1531
Phytoplankton, zooplankton, submerged vegetation and main nutrients have been monitored in 48 eutrophic ponds from the Brussels
Capital Region (Belgium) between 2005 and 2008. Nine ponds have been biomanipulated in order to improve their ecological quality
and prevent the occurrence of noxious cyanobacterial blooms. The 4-year study of a large number of ponds allowed identification
of the factors having the strongest influence on phytoplankton growth. Continuous monitoring of the biomanipulated ponds allowed
the significance of changes caused by biomanipulation to be tested as well as the main reasons of biomanipulation successes
and failures to be elucidated. The main factors controlling phytoplankton in the ponds studied appeared to be grazing by large
cladocerans and inhibition of phytoplankton growth by submerged vegetation. Biomanipulation resulted in a significant decrease
in phytoplankton biomass in general and biomass of bloom-forming cyanobacteria in particular that were associated with a significant
increase in large Cladocera density and size. In six out of nine ponds biomanipulation resulted in the restoration of submerged
vegetation. The maintenance of the restored clearwater state in the biomanipulated ponds was strongly dependent on fish recolonisation
and nutrient level. In the absence of fish, the clearwater state could be maintained by submerged vegetation or large zooplankton
grazing alone. In case of fish recolonisation, restoration of extensive submerged vegetation could buffer, to a considerable
degree, the effect of fish except for ponds with high nutrient levels. 相似文献
147.
F. L. Ludwig Elmer Robinson 《Journal of the Air & Waste Management Association (1995)》2013,63(3):102-105
It is shown how the Goetz Aerosol Spectrometer can be used to determine the particle size distribution of a specific component of a mixed atmospheric aerosol. The method requires no micrographic counting, but does require that sensitive quantitative chemical analysis methods be available for the compounds of interest. The accuracy of the method and the sensitivity limitations are briefly discussed. 相似文献
148.
149.
150.
F. L. Ludwig H. S. Javitz A. Valdés 《Journal of the Air & Waste Management Association (1995)》2013,63(10):963-967
A methodology for determining regional ozone design values and the expected number of exceedances is described. The methodology was applied to data bases for one year or less from four U.S. urban areas: Houston, Los Angeles, Philadelphia, and St. Louis. The effects of reducing numbers of stations in a network were tested, and it was concluded that networks of nine or ten appropriately selected stations are adequate for estimating design values. Using the methodology described, the expected number of exceedances tends to be underestimated when using smaller networks; however, this appears to be an artifact of the conservative approach taken in developing the methodology. 相似文献