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351.
Information helps decision makers to address and to decide about environmental problems. In the context of climate change adaptation, often knowledge is missing on how the available information from impact models affects the decision-making process. The main aim of this study was to explore the extent of ambiguity and how new climate change information influenced decision of forest planners. We investigated changes in decisions of planners about forestry actions representing species choice and forest tourism and expiry dates of these actions leading to environmental constraints in the provision of ecosystem services. Forest planners evaluated expiry dates using four forest ecosystem services: forest production, stand yield class, sequestered carbon, and potential tourism. Data were collected during workshops with eleven forest planners from three forest districts in Scotland. Presented climate change information modified the understanding and frames of planners about forestry actions assessed with accompanying expiry dates. Changes in the frames of planners often result in both earlier and later expiry dates. Ambiguity of planners was found to be dependent on diversity in frames and difficulty in evaluating multiple ecosystem services. These findings imply that due to ambiguity forest planners might find it hard to choose climate change adaptation measures and researchers can struggle to convince planners with new research findings.  相似文献   
352.
The article summarizes outcomes of a biomass study conducted in a young speckled alder plantation on a cold mountain site. At this location, the previously existing old forest was clear felled because of damage from air pollution, and present-day surface humus is in need of restoration. The intention of this study was to quantify the biomass and nutrients accumulated by alders and their components and assess whether the initial fertilization resulted in increased biomass production and nutrient accumulation in the biomass. Besides the control, two fertilized treatments were installed. In the surface treatment (SUT), the amendment was applied as a base dressing in small circles around trees. In the planting-hole treatment (PHT), the amendment was incorporated into soil inside the planting holes. Five growth seasons after planting and fertilization, six alders from each treatment were harvested including roots. Their biomass was quantified and analyzed for macroelements. The greatest pool of dry mass (DM) was branches in the control and stem wood in the fertilized treatments. The greatest pools of macroelements were leaves and branches. The most pronounced effects of fertilization were recorded in the DM and consequently in the absolute quantities of nutrients. The DM of an average tree in the control, SUT, and PHT was 85, 226, and 231 g, respectively. The absolute contents of nutrients per tree in the fertilized treatments showed the following increases, as compared with the control: (N) 2.5–2.6 times; (P) 1.6–2.4 times; (K) 1.8–2.1 times; and (Mg) 1.8–2.0 times, respectively. Speckled alder responded positively to fertilization.  相似文献   
353.
Mitigation and Adaptation Strategies for Global Change - Climate change mitigation policies for the land use, land use change, and forestry (LULUCF) sector are commonly assessed based on marginal...  相似文献   
354.
The preen gland is a holocrine sebaceous gland of the avian integument which produces an oily secretion that is spread on the plumage during preening. It has been suggested that birds may defend themselves against feather-degrading bacteria (FDB) and other potential pathogens using preen gland secretions. However, besides some in vitro studies, the in vivo bacterial inhibitory effects of the preen oil on the abundance of feather-associated bacterial species has not yet been studied in passerines. Here we tested the effect of gland removal on the abundance of FDB and other-cultivable bacterial loads (OCB) of male house sparrows (Passer domesticus). Our results did not support earlier results on in vitro antibacterial activity of preen oil against FDB since the absence of the preen gland did not significantly affect their loads related to the control birds. In contrast, we found that preen gland removal led to higher loads of OCB. This result suggests that the antimicrobial spectrum of the preen oil is broader than previously thought and that, by reducing the overall feather bacterial loads, the preen gland could help birds to protect themselves against a variety of potentially harmful bacteria.  相似文献   
355.
Acidifying oceans are predicted to fundamentally alter marine ecosystems. Over the next century, acute studies suggest that the impacts of climate change on marine organisms and ecosystems may be catastrophic. To date, however, little is known about whether the response of marine organisms varies within a species and whether this provides a potential ??adaptive capacity??. Here, we show that selectively bred lines of the ecologically and economically important estuarine mollusc, the Sydney rock oyster Saccostrea glomerata, are more resilient to ocean acidification than the wild populations. When reared at elevated pCO2, we found a 25% reduction in shell growth of the selectively bred population of the Sydney rock oyster, Saccostrea glomerata, compared to a 64% reduction in shell growth of wild populations. This study shows that there are significantly different sensitivities to ocean acidification even within the same species, providing preliminary evidence that selective breeding may be a solution for important aquaculture industries to overcome the future effects of ocean acidification.  相似文献   
356.
Water ecosystems are threatened by accidental spills of pollution. Rapidity and trueness of information gathering the biological impact of accidental pollution is crucial for the efficiency of the minimisation of possible deterioration of ecosystems and for success in detecting the source of pollution. Due to the randomised occurrence of accidental spills the only way to quickly detect hazardous situations is to perform continuous monitoring of surface water quality. The current situation in the field of early warning in the International Odra (Oder) River basin is not satisfactory. The actual number of monitoring stations and list of routinely continuously monitored parameters are not able to meet the needs of sensitive and rapid detection of biological impact of accidental pollution spills. An effort to change this unfavourable situation was the reason for the offer survey, selection and a model operation of a commercially produced biological monitoring device. This apparatus was located on the border-line profile on the territory of the Czech Republic and represented the first and only one tool of continual biological monitoring of surface water quality in the International Odra (Oder) River Basin. The selected apparatus was the Daphnia Toximeter produced by the firm bbe Moldaenke (Kiel, Germany). This device exploited for rapid detection of changes of biological quality of surface water evaluation of behavioural response of monitoring organisms??daphnids. Five years of model operation proved its suitability for early warning purposes. The apparatus was reliable in function and sensitive enough to detect the deterioration of the biological quality of the river water. The given examples document its applicability not only for detection of accidental spills but also of illegal emissions of pollution, which are very often toxic.  相似文献   
357.
Toxicity of lead in soil is well documented and established. Phytoremediation has gained attention as a cheap, easily applicable, and eco-friendly clean-up technology. Chemical methods are used to assess exact levels and type of pollutants but heavy metal content in soil can also be evaluated indirectly by estimation of phytotoxicity levels using bioassays. Plant bioassays through fast germinating cereals can indicate not only the level of pollution and its effects on growth and survival but also the progress of phytoremediation process. The performance of barley Hordeum vulgare L. seedlings as bioassay for assessment of changes in the levels of lead (Pb) at three concentrations, i.e., 300 (T1), 600 (T2), and 1,200 ppm (T3) in the soil was evaluated while testing the efficiency of Crinum asiaticum L. as a phytoremedial tool. At the first assessment, i.e., 30 DAT (days after treatment) shoot and root lengths of seedlings decreased with increasing concentrations of Pb. As the study progressed, a decrease in levels of Pb was accompanied by better germinability and growth of barley. At 120 DAT seedling growth in all the treatments were comparable to control. In T1, T2, and T3 soils, 74.5%, 83.7%, and 91.2% reduction in lead content was observed at 120 DAT. Highly significant correlations between decreasing pollutant (Pb) content in the soil, seed germination, and seedling growth of barley H. vulgare were found. The differences in root and shoot length as well as overall growth pattern are indicative of the suitability of barley as a bio-monitoring tool.  相似文献   
358.
The identification of appropriate companions and mates is essential to both speciation and the maintenance of species through prezygotic isolation. In many birds, social assortment is mediated by vocalizations learned through imitation. When imitative vocal learning occurs throughout life, emergent shared signals reflect current social associations. However, when vocal and genetic variation arises among populations, shared learned signal variants have a potential to reflect cultural or genetic origin and to limit social and reproductive intermixing, provided that signal learning occurs prior to dispersal. The red crossbill (Loxia curvirostra) is a bird species in which discrete contact call variants are associated with morphological variation, raising the possibility that learned calls play a role in limiting intermixing. I examined the process of early call learning to determine if contact call variants have a potential to limit intermixing in crossbills. I conducted a captive playback study to nestlings to evaluate potential learning predispositions. I also cross-fostered nestlings to adoptive adult pairs of either their own or a different call variant than their biological parents to assess the degree of vocal learning plasticity. Results show that young crossbills imitate the call structures of adoptive parents, generating shared family-specific calls, which could facilitate family cohesion. Learning processes that generate family-specific calls could also ensure that discrete call variants are transmitted across generations, making call variants reliable signals of crossbills’ morphological and genetic backgrounds.  相似文献   
359.
The bio-geographical significance of Rhododendron ponticum spp. baeticum (Ericaceae) as a relict species is well recognized. However, out of its native habitat it is an invasive exotic considered a major threat to natural ecosystems in areas of Atlantic Western Europe. The studies on the impact of Rhododendron influence on soil organic matter composition and associated ecological implications, i.e. presence of bioactive compounds with ecological significance, are limited. This work describes the soil lipid assemblage in three sites under Rhododendron stands and adjacent sites with deciduous oak (Quercus canariensis), both in their native habitats in Southern Spain (Sierra de Luna, Cádiz). The results are discussed in terms of organic matter dynamics and the presence of molecules that may be associated with Rhododendron invasive success. The soils are acid Xerochrepts formed on siliceous sands. Composite soil samples were taken at two depths (0?C10?cm and 10?C20?cm) and soxhlet extracted with a dichloromethane-methanol mixture (3:1). Soil lipid assemblage was studied by GC/MS after fractionation and appropriate derivatization of extracts. The qualitative chemical composition of soil extractable lipids under Rhododendron is reported here for the first time. Our results show that soil n-alkane and fatty acid distributions are compatible with an input from plant epicuticular waxes, as well as with the occurrence of selective preservation of long-chain fatty acids with depth. The pattern of short-chain n-alkanes found in surface samples indicates an anthropogenic contamination threat from nearby industrialized areas of ??Campo de Gibraltar??. The presence of branched iso and anteiso C15 and C17, ??-hydroxy fatty acids and the sterol brassicasterol points to high microbial soil activity. Finally, the pentacyclic triterpenes taraxerone and taraxerol were detected in soils with Rhododendron but not with Quercus. These are known bio-active plant compounds and could be related with the effectiveness of Rhododendron as an invasive exotic species.  相似文献   
360.
Rapid methods are needed to analyse air pollutants such as polycyclic aromatic hydrocarbons (PAHs). Reliable semi-quantitative gas standards were required for the development of a laser-induced fluorescence (LIF) method for polycyclic aromatic hydrocarbon analysis, based on sampling of air onto multi-channel polydimethylsiloxane rubber traps. Easily constructed diffusion tubes provided naphthalene vapour at ~2 ng s−1. A gas chromatographic fraction collection method for loading less volatile PAHs onto the traps from a flame ionization detector outlet was developed and optimized. The accuracy of the method, which can be further optimized, was sufficient for initial LIF screening tests to flag samples exceeding threshold PAH levels for subsequent quantitative GC–MS analysis.  相似文献   
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