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41.
42.
The antifungal activity of molecular identified Chilean saprobiontic fungi, Trichoderma viride, Schizophyllum commune and Trametes versicolor, on the fungal plant pathogens Botrytis cinerea and Fusarium oxysporum, and the saprotrophic mould Mucor miehei was investigated using two types of inhibition bioassay: (1) bi-compartmented Petri dishes and (2) two Erlenmeyer flasks connected by their upper parts. The chemical composition of volatile organic compounds (VOCs) released by saprobiontic fungi was also investigated using headspace solid-phase microextraction (SPME) and gas chromatography/mass spectrometry (GC-MS) analysis. Of the saprobiontic fungi evaluated, one isolate of S. commune showed the highest inhibitory activity against B. cinerea and M. miehei, 86.0±5.4 and 99.5±0.5% respectively. The volatile profiles of fungal isolates were shown to contain a different class of compounds. The major components in the headspace of mycelial cultures were 6-pentyl-α -pyrone (T. viride), ethanol and β -bisabolol (S. commune), and a sesquiterpene alcohol (Tr. versicolor). This is the first study reported on the release of VOCs by Chilean native fungi and their antifungal activity wrt. plant pathogenic fungi.  相似文献   
43.
The possibility to include in expanded clay little amounts of metallic ions present in waste material, without significant influence on the environment, was investigated. In this article, known quantities of cadmium(II), lead(II), chromium(III), and chromium(VI) were added to a mixture of raw pit clay, adding a small amount of mineral oil. The resultant paste was heated at 1200°C, in conditions to provide the commercial product with the best characteristics of lightness. The obtained pellets were analyzed in two ways. A sample of expanded clay was crushed, added to with KNaCO3 and melted. The melted mass, after cooling, was dissolved in HCl or in water and analyzed. The composition of the raw pit clay was analyzed as a blank. In parallel, pellets were subjected to a leaching process and the eluate was analyzed for the added cations. The concentration of the metal ions in the leached water is negligible compared with that generally admitted in drinking water.  相似文献   
44.
Biogas production from anaerobic digestion of chicken feathers with swine manure or slaughterhouse sludge was assessed in two separate experiments. Ground feathers without any pre-treatment were added to 42-L digesters inoculated with swine manure or slaughterhouse sludge, representing 37% and 23% of total solids, respectively and incubated at 25 °C in batch mode. Compared to the control without feather addition, total CH4 production increased by 130% (P < 0.001) and 110% (P = 0.09) in the swine manure and the slaughterhouse sludge digesters, respectively. Mixed liquor NH4N concentration increased (P < 0.001) from 4.8 and 3.1 g/L at the beginning of the digestion to 6.9 and 3.5 g/L at the end of digestion in the swine manure and the slaughterhouse sludge digesters, respectively. The fraction of proteolytic microorganisms increased (P < 0.001) during the digestion from 12.5% to 14.5% and 11.3% to 13.0% in the swine manure and the slaughterhouse sludge digesters with feather addition, respectively, but decreased in the controls. These results are reflective of feather digestion. Feather addition did not affect CH4 yields of the swine manure digesters (P = 0.082) and the slaughterhouse sludge digesters (P = 0.21), indicating that feathers can be digested together with swine manure or slaughterhouse sludge without negatively affecting the digestion of swine manure and slaughterhouse sludge.  相似文献   
45.
Hierarchical relationships among different compass systems in long-distance migrants are still a matter for discussion because different studies have led to highly variable and apparently contradictory results. We carried out cue-conflict experiments during spring migration on pied flycatchers Ficedula hypoleuca (Passeriformes, Muscicapidae). Birds were exposed to a conflict between celestial and magnetic information by altering the polarized light pattern or magnetic field. The polarization pattern was shifted (±90°) with filters, whereas the magnetic field was altered (+90°) through Helmholtz coils. Birds were tested in modified Emlen funnels both before and after the cue conflict; during the tests, only the natural magnetic field was available. This protocol was designed to test whether the experimental birds recalibrated their magnetic compass on the directional information derived from the light polarization pattern when the region near the horizon was visible during the conflict. Contrary to this expectation, we did not record any significant shift in magnetic orientation after one or repeated exposures to the cue conflict. Our results support earlier studies, which suggest that the magnetic field is the primary compass cue during the migratory period.  相似文献   
46.
Environmental impact assessments in Brazil have usually focused solely on project-related issues without considering the regional context. Although required by current environmental legislation, cumulative impact assessments have not been included in the overall environmental assessment of projects. However, in recent Strategic Environmental Assessment (SEA) studies of policies, plans, and programs undertaken on a voluntary basis in support of the decision-making process, this kind of assessment has been performed especially with respect to air quality. This paper presents the application of a methodology for the quantification of cumulative impacts on air quality under high uncertainty caused by various mining activities in a single region that is recommended for SEA studies. In this way, the methodology presented here is suitable for areas lacking detailed modeling information. The developed approach uses a relatively simplified mathematical model, lowering information gathering costs and requiring little processing time. The application of the methodology is illustrated in the case of a SEA of the Corumbá Mining and Industrial Complex Development Program. Despite the lack of data needed for a minimum characterization of conditions of the area surrounding the region modeled, the quantification of impact cumulativeness on air quality has played an important role in the context of the SEA.  相似文献   
47.
The present work evaluates the possible bioconversion of wet olive cake by low-cost biostabilization (vermicomposting process). Wet olive cake fresh (WOC), precomposted (WOCP), or mixed with biosolids (WOCB), were vermicomposted for 6 months to obtain organic amendments for agricultural and remediation purposes. The results showed initial differences depending on previous treatment. WOCP was initially more stable, presented a low C:N ratio, and showed more dehydrogenase and urease activity. By contrast, there was no dehydrogenase activity initially in WOC and WOCB, due to the presence of some different types of polyphenols. Finally, the end product showed relatively higher amounts of total nitrogen and humic acid and met the standard of quality for composts and vermicomposts for use both in conventional and organic agriculture and soil-restoration programs.  相似文献   
48.
The Environmental Impact Assessment (EIA) procedure should predict and identify the major impacts of a project development that may cause specific spatial and temporal effects. Early in the EIA, the scoping stage provides all the relevant information on the impacts of the project alternatives. In particular, potential effects on the territorial network such as habitat connectivity loss and accessibility improvements should be taken into account in the various proposed layout alternatives when evaluating transport infrastructure projects. However, several authors have identified deficiencies in practice. The aim of this article is to provide a methodology for the assessment of these territorial impacts using adequate indicators in the early stages of the EIA procedure.

The proposed method is based on a comparison of a range of alternative layouts for a railway line linking two population centres, using indicators calculated with geographic information systems. The methodology was applied to a case study – the rail link between Huelva (Spain) and Faro (Portugal) – and the high speed rail (HSR) and conventional rail were evaluated in different layouts. The method was effective in spatially identifying significant impacts on accessibility improvements, which occurred closer to the cross border area. The conventional railway alternatives have similar accessibility values to the HSR. The results also reveal that connectivity loss is not limited to the area around the infrastructure, but extends throughout the territory. The results are at variance with the initiative proposed by Spanish and Portuguese transport decision-makers, and raise the possibility of selecting a conventional railway option. An adequate territorial evaluation methodology enables the new action to be correctly assessed, and supplies the information required to propose the most suitable alternative from a socio-economic and environmental standpoint, regardless of whether this proposal was initially included in the transport policy.  相似文献   

49.
Influence of different parameters on biosurfactant (BS) activity was carried out on strains that were isolated from the polychaetes Megalomma claparedei, Sabella spallanzanii and Branchiomma luctuosum and additional 30 strains that were previously identified as potential BS producers from crude oil enrichments of the same polychaete specimens. The selection of BS-producing strains from polychaete natural samples was carried out by using standard screening tests. The BS activity by each isolate was evaluated for the effect of salinity and temperature on emulsion production and surface tension reduction, during incubation in mineral medium supplemented with tetradecane or diesel oil. All isolates showed a similar time course of BS activity, and the latter was more influenced by salinity rather than temperature. Some of the BS producers belonged to genera that have not (i.e. Citricoccus, Cellulophaga, Tenacibaculum and Maribacter) or have poorly been (Psychrobacter, Vibrio, and Pseudoalteromonas) reported as able to produce BSs. This is remarkable as some of them have previously been detected in hydrocarbon-enriched samples. Results confirm that filter-feeding polychaetes are an efficient source for the isolation of BS producers.  相似文献   
50.
Ambient air samples were collected in five locations around a polychlorobiphenyl (PCB) production plant in a highly industrialized city in the north of Italy, for the analysis of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) and PCBs.PCDD/F atmospheric concentrations were lower than those generally detected in urban areas, while PCB concentrations were higher than in urban and industrialized areas in other countries, especially in the locations closest to the plant. To identify source emissions responsible for air pollution we used principal component analysis (PCA) to compare the “fingerprint” of the air in Brescia with some source-related experimental and published data. This analysis showed that the PCDD/F fingerprints were more similar to steel plant emission data, while none of the PCB air patterns were comparable to emission profiles, indicating that different sources are responsible for the concentration of these two pollutants. The highest PCB concentrations detected in the areas closest to the chemical plant are indicative of its impact on the surrounding environment.  相似文献   
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