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21.
Shale We Drill? Discourse Dynamics in UK Fracking Debates   总被引:1,自引:0,他引:1  
This article examines competing political discourses surrounding shale extraction in the UK. It asks how these meanings are communicated and why certain understandings of the issue gain prominence. Drawing on discourse analysis and framing studies, the article first distinguishes two competing coalitions (pro- and anti-shale) and their shared narratives or ‘storylines’ (shale opportunity versus shale threat). Through a systematic examination of press reports, websites and public documents, it identifies opposing discursive frames used to shape understanding, meaning and debates, and assesses their resonance and power. The article builds on existing interpretive studies by providing a finer-grained analysis of discourse success, and a greater emphasis on the coalition members who shape and deliver the agreed storyline. It argues that the anti-shale coalition in the UK has thus far enjoyed greater discourse success for two reasons: firstly, because the pro-shale coalition lacks trustworthy messengers; secondly, because shale opponents have successfully expanded the debate beyond economic or environmental concerns to include potent issues of local power and democracy.  相似文献   
22.
Climate-induced water availability changes in Europe   总被引:1,自引:0,他引:1  
Water availability changes in Europe are discussed in this paper, as seen in a perspective of climatic change. Such changes will be assessed in terms of the shifts in the watering of terrestrial ecosystems, as well as the shifts in the availability in terrestrial freshwater systems. A changing climate will have a major impact on the availability of water. Both wetter and drier conditions will have major implications for societal activities and land use patterns (e.g., agriculture, urban activities, waste water disposal, etc.).Some future research and monitoring activities are proposed by the authors to assess linkages in hydrological shifts to changes in land use patterns.  相似文献   
23.
Eco-certification is widely considered a tool for reducing environmental impacts of aquaculture, but what are the likely environmental outcomes for the world’s fastest growing animal-food production sector? This article analyzes a number of eco-certification schemes based on species choice, anticipated share of the global seafood market, size of eligible producers, and targeted environmental impacts. The potential of eco-certification to reduce the negative environmental impacts of aquaculture at scale presently appears uncertain as: (a) certification schemes currently focus on species predominantly consumed in the EU and US, with limited coverage of Asian markets; (b) the share of certified products in the market as currently projected is too low; (c) there is an inequitable and non-uniform applicability of certification across the sector; (d) mechanisms or incentives for improvement among the worst performers are lacking; and (e) there is incomplete coverage of environmental impacts, with biophysical sustainability and ecosystem perspectives generally lacking.  相似文献   
24.
Since biogas production is becoming increasingly important the understanding of anaerobic digestion processes is fundamental. However, large-scale digesters often lack online sensor equipment to monitor key parameters. Furthermore the possibility to selectively change fermenting parameter settings in order to investigate methane output or microbial changes is limited. In the present study we examined the possibility to investigate the microbial community of a large scale (750,000 L) digester within a laboratory small-scale approach. We studied the short-term response of the downscaled communities on various fatty acids and its effects on gas production and compared it with data from the original digester sludge. Even high loads of formic acid led to distinct methane formation, whereas high concentrations of other acids (acetic, butyric, propionic acid) caused a marked inhibition of methanogenesis coupled with an increase in hydrogen concentration. Molecular microbial techniques (DGGE/quantitative real-time-PCR) were used to monitor the microbial community changes which were related to data from GC and HPLC analysis. DGGE band patterns showed that the same microorganisms which were already dominant in the original digester re-established again in the lab-scale experiment. Very few microorganisms dominated the whole fermenting process and species diversity was not easily influenced by moderate varying fatty acid amendments - Methanoculleus thermophilus being the most abundant species throughout the variants. MCR-copy number determined via quantitative real-time-PCR - turned out to be a reliable parameter for quantification of methanogens, even in a very complex matrix like fermenter sludge. Generally the downscaled batch approach was shown to be appropriate to investigate microbial communities from large-scale digesters.  相似文献   
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Which populations are replenished primarily by immigrants (open) and which by local production (closed) remains an important question for management with implications for response to exploitation, protection, and disturbance. However, we lack methods for predicting population openness. Here, we develop a model for openness and show that considering habitat isolation explains the existence of surprisingly closed populations in high-dispersal species, including many marine organisms. Relatively closed populations are expected when patch spacing is more than twice the standard deviation of a species'. dispersal kernel. In addition, natural scales of habitat patchiness on coral reefs are sufficient to create both largely open and largely closed populations. Contrary to some previous interpretations, largely closed marine populations do not require mean dispersal distances that are unusually short, even for species with relatively long pelagic larval durations. We predict that habitat patchiness has strong control over population openness for many marine and terrestrial species with a highly dispersive life stage and relatively sedentary adults. This information can be used to make initial predictions about where populations will be more or less resilient to local exploitation and disturbance.  相似文献   
27.
Private forest owners are the main forest ownership group within Europe, and important conservation values have been found on their land. Yet, small plot sizes, societal heterogeneity, and structural changes impede developing and implementing effective conservation programs in private forests. We present a systematic literature review focusing on small-scale private forest owners and their perspectives on nature conservation by synthesizing research approaches, social-ecological drivers, and policy recommendations. Conservation perspectives were positively related to female gender, higher levels of education, formalized forest management, an active relation to the forest, and ecological values of the property. In contrast, high age, rural orientation, economic forest management factors, large parcel size, and economic and sentimental property values negatively influenced conservation perspectives. Applying a natural resource conflict management framework, we synthesized recommendations covering three dimensions: substance, procedure, relationship. Considering perspectives of small-scale private forest owners in current forestry decision-making has great potential to strengthen sustainable forest management that integrates nature conservation and resource use.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01615-w.  相似文献   
28.
Probabilistic economic analysis, including uncertainty of probabilities and consequences of project risks, is not widely used in remediation projects. This article presents a project risk assessment (PRA) method to identify, quantify, and analyze risks in remediation projects. The suggested method is probabilistic and includes uncertainty analysis of input variables based on expert judgment. It was originally developed as a part of a sustainability assessment tool, but is viable as a stand‐alone tool for remediation projects. The method is applied to a case study: a former paint factory that is being redeveloped into a residential area. The PRA method is used for analyzing and comparing the project risks associated with four remediation options, all including excavation but with different degrees of onsite treatment. The result of the case study application shows which alternative has the lowest mean risk cost, the highest probability to have the lowest risk cost, and how the risk costs are distributed, but also, importantly, helps the user to prioritize between risk‐reduction measures. ©2015 Wiley Periodicals  相似文献   
29.
Standardized household waste was mixed with different litter amendments, straw, leaves, hardwood shavings, softwood shavings, paper, and sphagnum peat, resulting in six compost mixtures. In addition non-amended household waste was composted. Composting was done in small rotatable bins and compost samples were taken on a regular basis until day 590. Extraction and analysis of wet compost samples showed no evidence for the presence of chloroorganic compounds. Drying and re-wetting of compost samples, however, revealed that chloromethoxybenzaldehyde (CMBA) was formed in all composts at concentrations varying between 5.6 and 73.4 microg kg(-1) dry matter. CMBA was not present in the original materials. During composting, there was a clear positive relation between formation of CMBA and microbial activity, as indicated by C losses and temperature. Formation took place during the most intensive phase of composting when C losses were highest. Under anaerobic conditions, however, which prevailed initially in the non-amended compost, no CMBA was formed. Calculation of total amounts of CMBA in composts revealed that there was a small decrease during storage in the hardwood, peat, and softwood composts. However, all composts contained CMBA after 590 days. The mean concentration was 33.4 microg kg(-1) dry matter (s.d. = 21.9). Possible biocidal effects of composts when used in cultivation may be explainable by the presence of natural toxic compounds formed during composting.  相似文献   
30.
Mesograzers are thought to play a critical role in seagrass beds by preventing overgrowth of ephemeral algae. On the Swedish west coast, eelgrass Zostera marina has decreased in recent decades as a result of eutrophication and increased growth of macroalgal mats (mainly filamentous Ulva spp. and Ectocarpales), with no indication of grazer control of the algae. The aim of this study was to investigate the ability of the amphipod Gammarus locusta to control algal blooms during nutrient-enriched and ambient conditions, using a combination of laboratory, field and model studies. Laboratory experiments demonstrated that juvenile and adult G. locusta could consume both Ulva spp. and Ectocarpales, but that consumption of Ulva spp. was significantly higher. Cannibalism was common in individual treatments involving multiple size-classes of G. locusta, but only large, male gammarids consumed smaller juveniles in the presence of Ulva spp. as an alternative food source. However, no negative effects of cannibalism were found on total grazing impact. A model using size-specific grazing rates and growth rates of G. locusta and of Ulva spp. suggests that approximately 62 young juvenile, or 27 adult G. locusta are needed per gram DW of Ulva spp. to control the algal growth during ambient nutrient conditions, and approximately 2.6 times as many gammarids during enhanced nutrient conditions. On the Swedish west coast, densities and mean sizes of G. locusta in eelgrass beds are below these critical values, suggesting that the gammarids will not be able to control the growth of the filamentous macroalgae. However, in the field cage experiment, immigration of juveniles and reproduction of encaged adult G. locusta resulted in unexpectedly high densities of G. locusta (>4,000 individual m−2), and very low biomass of Ulva spp. in both ambient and nutrient-enriched treatments. Although the high numbers of juveniles in all cages precluded any significant treatment effects, this suggests that in the absent of predators, the population of G. locusta can grow significantly and control the biomass of Ulva spp. Furthermore, low grazing of Ectocarpales in the laboratory and high biomass of these filamentous brown algae in the field indicate a preference for the more palatable green algae Ulva spp. This study indicates that the high grazing capacity of G. locusta, in combination with high reproduction and growth rates, would allow the amphipod to play a key role in Z. marina ecosystems by controlling destructive blooms of filamentous green algae. However, high predation pressure appears to prevent large populations of G. locusta in eelgrass beds on the Swedish west coast today.  相似文献   
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