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81.
Surrogate approaches are widely used to estimate overall taxonomic diversity for conservation planning. Surrogate taxa are frequently selected based on rarity or charisma, whereas selection through statistical modeling has been applied rarely. We used boosted‐regression‐tree models (BRT) fitted to biological data from 165 springs to identify bryophyte and invertebrate surrogates for taxonomic and functional diversity of boreal springs. We focused on these 2 groups because they are well known and abundant in most boreal springs. The best indicators of taxonomic versus functional diversity differed. The bryophyte Bryum weigelii and the chironomid larva Paratrichocladius skirwithensis best indicated taxonomic diversity, whereas the isopod Asellus aquaticus and the chironomid Macropelopia spp. were the best surrogates of functional diversity. In a scoring algorithm for priority‐site selection, taxonomic surrogates performed only slightly better than random selection for all spring‐dwelling taxa, but they were very effective in representing spring specialists, providing a distinct improvement over random solutions. However, the surrogates for taxonomic diversity represented functional diversity poorly and vice versa. When combined with cross‐taxon complementarity analyses, surrogate selection based on statistical modeling provides a promising approach for identifying groundwater‐dependent ecosystems of special conservation value, a key requirement of the EU Water Framework Directive.  相似文献   
82.
This article evaluates the impacts of integrated environmental permits on the environmental performance of Finnish pulp and paper industry. It assesses the performance of the Finnish pulp and paper mills in relation to the EU best available techniques (BAT) associated emission levels and compares the emission limit values and product specific emissions of the mills with non-integrated permits to those of the mills with new integrated permits. A set of practical indicators for the assessment of BAT, local conditions and transboundary effects is presented and discussed. Moreover, the paper highlights some significant cross-media aspects in the Finnish pulp and paper industry.  相似文献   
83.
The increasing availability of spatial data inspires the exploration of previously less-studied, yet regionally and nationally important areas, such as the Irrawaddy and Salween River Basins in Southeast Asia. This article documents our experience using global datasets to create environmental basin profiles in these two basins. Our approach draws on the concepts of freshwater vulnerability assessments that guided the selection of indicators. Data on land use, population distribution and fertilizer load were used. The unit of analysis was chosen to distinguish areas with similar bio-geographical characteristics, such as the critical delta areas. Results were further discussed for sub-areas that experience relatively the most pressure in terms of examined indicators within the studied area. The river mouths of both rivers had the most intensive land use and high population density. They are also home to important ecosystems and are sensitive to changes in upstream areas. Our study presents a concise and spatially distributed view of the environmental basin profiles of the Irrawaddy and Salween River Basins. The analysis also provides some interesting methodological insights about the potential of public macro-scale datasets for environmental assessment. The spatial approach allowed the analysis of different indicators, providing a platform for data integration as well as a visually powerful overview of the study area. Yet, the use of macro-scale datasets entails challenges. Despite improvements, the assessment process tends to be driven by the availability and quality of data, rather than by the actual research and management needs. The greatest utility of macro-scale datasets lies—at least in data-poor areas—in larger scale comparative analyses between the basins and their different sub-areas.  相似文献   
84.
Environmental Geochemistry and Health - Environmental pollution is becoming one of the most important global problems. Understanding the main factors affecting accumulation of toxic trace elements...  相似文献   
85.
86.
Summary. Vole feeding amongst herbal willows that have a high concentration of salicylates in their bark and leaves, and may therefore be cultivated for use as raw material for herbal medicine was tested in the field and in laboratory conditions. Eight clones of dark-leaved willow (Salix myrsinifolia Salisb.) were cultivated for two years with six different methods combining three fertilisation levels (none, low and high), black plastic mulch applied for suppressing weed competition and unmulched control. Samples for the laboratory feeding trial were taken from the unfertilised plants during willow winter dormancy and twigs were fed to 16 voles as a multi-choice experiment. The bark area removed was calculated from image analysis of the material left by the voles. The diameter and the bark thickness of the twigs were measured. Concentrations of salicin, salicortin, HCH-salicortin, picein, triandrin, triandrin derivative, gallocatechin, (+)-catechin, luteolin-7-glucoside, hyperin, total condensed tannins and total nitrogen were measured from the twigs fed to voles in the laboratory. Browsing by a natural population of voles amongst winter-dormant willows was measured in the field. In the laboratory, voles browsed on 80% of the twigs and in the field voles browsed on 33% of the twigs. Vole feeding followed similar patterns in the field and in the laboratory experiment; feeding was clearly higher amongst the plants grown in unmulched control compared to those in plastic mulch. The same clones, 1, 2 and 6 were preferred in both experiments. Voles preferred thin twigs to thick ones. Feeding correlated negatively with concentrations of salicylates and tannins. As vole feeding seems to be highly affected by willow cultivation method and plant genotype, careful selection of cultivated clones and cultivation methods can enhance the reliability of herbal willow cultivation.  相似文献   
87.
Ben Mepham has proposed that a ``matrix' beused in the analysis of ethical problems in foodproduction and elsewhere. In particular cases, thismatrix would ideally cross the most important moralprinciples involved, and the individuals and groupsaffected by the decisions. In the following, Mepham'smodel is assessed in the case of geneticallyengineered bovine growth hormone. My argument is thata more straightforwardly ``consequentialist' analysiscan draw attention to the problems of using thehormone better than Mepham's original proposal. It ispossible, however, that some nuances will be lost inthe process. I do not, therefore, argue for theoverall superiority of my suggestion – it is merelya slightly different, and perhaps sometimes a morepromising, way to analyze the ethical dimensions offood production and marketing.  相似文献   
88.
89.
We investigated the reliability and stability of favourite place selections and evaluations of place attachment over a 10-month period. A simple random sample of 1273 respondents representative of the population of the two largest cities in Finland completed a mailed questionnaire. Reliability data was obtained in a second questionnaire (N = 427). We obtained five main favourite place types which were extensively managed natural settings (mainly urban woodlands), urban green spaces (mostly parks), waterside environments, exercise and activity/hobby areas, and indoor and outdoor urban areas. Sixty-four percent of the respondents in the second survey selected the same main favourite place type as 10 months earlier, which is more than what might be expected by chance. Extensively managed natural settings (mainly urban woodlands) and waterside environments were reselected most often. Indoor and outdoor urban favourite places had the lowest stability. We found evidence of people being more consistent in their attachment to natural favourite places than to urban favourite places. The findings lend further credence and credibility to earlier results concerning self-regulation and restorative experiences in favourite places.  相似文献   
90.
The idea that trading is more costly the thinner the market is is common in most studies of market exchange with frictions. Surprisingly, this element is lacking from previous attempts to allow for frictions in pollution permit markets. This paper considers a CO2 cap-and-trade model where trading costs develop endogenously as a function of the market size. The pre-trade allocation of permits determines whether the market size can be strongly influenced by expectations that have a role because of adjustment costs. The pre-trade allocation also sets preconditions for endogenously vanishing trading costs and thus has nonstandard effects on long-run trading levels and market allocations.  相似文献   
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