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1.
Thenearsurfacedisposalisthemainlydisposalmethodforlowintermediatelevelradioactivesolidwaste(LILW)inmanycountries.Usually,thedisposalwayinthedisposalunitistheconcretesolidificationisputandpiledinarray,andthebackfillandbuffermaterialisfilledbetweentheses…  相似文献   

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Within the initiatives for poliomyelitis eradication by WHO, Italy activated an environmental surveillance (ES) in 2005. ES complements clinical Acute Flaccid Paralysis (AFP) surveillance for possible polio cases, detects poliovirus circulation in environmental sewage, and is used to monitor transmission in communities. In addition to polioviruses, the analyses comprised: (i) the monitoring of the presence of non-polio enteroviruses in sewage samples and (ii) the temporal and geographical distribution of the detected viruses. From 2009 to 2015, 2880 sewage samples were collected from eight cities participating in the surveillance. Overall, 1479 samples resulted positive for enteroviruses. No wild-type polioviruses were found, although four Sabin-like polioviruses were detected. The low degree of mutation found in the genomes of these four isolates suggests that these viruses have had a limited circulation in the population. All non-polio enteroviruses belonged to species B and the most frequent serotype was CV-B5, followed by CV-B4, E-11, E-6, E-7, CV-B3, and CV-B2. Variations in the frequency of different serotypes were also observed in different seasons and/or Italian areas. Environmental surveillance in Italy, as part of the ‘WHO global polio eradication program’, is a powerful tool to augment the polio surveillance and to investigate the silent circulation or the re-emergence of enteroviruses in the population.  相似文献   

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This study investigates arsenic (As) accumulation and tolerance of duckweed Spirodela polyrhiza L: and its potential for As phytofiltration. S. polyrhiza was able to survive in high concentration of As(V) solution: The EC50 values ( SE) based on the external As(V) were (181.66 20.12) mol/L. It accumulated (999 95) mg As/kg dw when exposed in 320 mol/L As(V) solution for one week, and was able to take up appropriately 400 mg As/kg dw in tissues without a significant biomass loss. The EC50 values (the e ective concentration of As(V) in the nutrient solution that caused a 50% inhibition on biomass production) was (866 68) mg/kg dw for the tissues, indicating that S. polyrhiza had a high capability of As accumulation and tolerance. The uptake kinetic parameters Vmax was (55.33 2.24) nmol/(g dw min) and Km was (0.144 0.011) mmol/L. Within 72 hr, S. polyrhiza decreased As concentration in the solution from 190 to 113 ng/mL with a removal rate of 41%. The study suggested that this floating aquatic plant has some potential for As phytofiltration in contaminated water bodies or paddy soils.  相似文献   

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Noroviruses are the major cause of non-bacterial acute gastroenteritis outbreaks in humans, with few reports about the occurrence of the norovirus GIV strain. We investigated the presence of norovirus GIV in surface water (river, bay, and stream) and untreated sewage, and we determined a positivity rate of 9.4 % (9/96). The strains genotyped were GIV.1. To our knowledge, this is the first report of GIV in Brazil.  相似文献   

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Despite increasing interest in learning from Indigenous communities, efforts to involve Indigenous knowledge in environmental policy-making are often fraught with contestations over knowledge, values, and interests. Using the co-production of knowledge and social order (Jasanoff, 2004), this case study seeks to understand how some Indigenous communities are engaging in science-policy negotiations by linking traditional ecological knowledge (TEK), western science, and other knowledge systems. The analysis follows twenty years of Indigenous forest management negotiations between the Xáxli’p community and the Ministry of Forests in British Columbia (B.C.), Canada, which resulted in the Xáxli’p Community Forest (XCF). The XCF is an eco-cultural restoration initiative that established an exclusive forest tenure for Xáxli’p over the majority of their aboriginal territory—a political shift that was co-produced with new articulations of Xáxli’p knowledge. This research seeks to understand knowledge co-production with Indigenous communities, and suggests that existing knowledge integration concepts are insufficient to address ongoing challenges with power asymmetries and Indigenous knowledge. Rather, this work proposes interpreting XCF knowledge production strategies through the framework of “Indigenous articulations,” where Indigenous peoples self-determine representations of their identities and interests in a contemporary socio-political context. This work has broader implications for considering how Indigenous knowledge is shaping science-policy negotiations, and vice versa.  相似文献   

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Governments are promoting biofuels and the resulting changes in land use and crop reallocation to biofuels production have raised concerns about impacts on environment and food security. The promotion of biofuels has also been questioned based on suggested marginal contribution to greenhouse gas emissions reduction, partly due to induced land use change causing greenhouse gas emissions. This study reports how the expansion of sugarcane in Brazil during 1996–2006 affected indicators for environment, land use and economy. The results indicate that sugarcane expansion did not in general contribute to direct deforestation in the traditional agricultural region where most of the expansion took place. The amount of forests on farmland in this area is below the minimum stated in law and the situation did not change over the studied period. Sugarcane expansion resulted in a significant reduction of pastures and cattle heads and higher economic growth than in neighboring areas. It could not be established to what extent the discontinuation of cattle production induced expansion of pastures in other areas, possibly leading to indirect deforestation. However, the results indicate that a possible migration of the cattle production reached further than the neighboring of expansion regions. Occurring at much smaller rates, expansion of sugarcane in regions such as the Amazon and the Northeast region was related to direct deforestation and competition with food crops, and appear not to have induced economic growth. These regions are not expected to experience substantial increases of sugarcane in the near future, but mitigating measures are warranted.  相似文献   

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To investigate the potential role of allelopathy in plant interference and in the successful invasion of alien species Solidago canadensis, aqueous and ethanolic extracts from rhizomes, stems and leaves of S. canadensis were prepared and used as treatment solutions to assess their effects on seed germination and seedling growth in four target species, mulberry (Morus alba); morning glory (Pharbitis nil), wheat (Triticum aestivum) and rape (Brassiea campestris). Reduction and/or growth in germination and growth of the target plant species in the presence of both aqueous and ethanolic extracts at different concentrations indicated that the responses were species-specific and concentration-dependent. Generally, ethanolic extracts (especially from leaves) imposed stronger effects on both seed germination and seedling growth. Extracts with lower concentration at 0.001 g/ml dw could stimulate the seedling growth of rape and morning glory, whereas extracts at any given concentrations have inhibitory effects on wheat and mulberry. It is suggested that the aqueous and ethanolic extracts of all the three parts of S. canadensis have significant allelopathic effects. Although both inhibition and stimulation occurred in the germination and growth of the target species, extracts with higher concentrations definitely inhibit seed germination and seedling growth of all target plants. We suggest that allelopathy plays a more important role than other mechanisms do in the out-competition ofS. canadensis over other plants, and make it invasive in new habitats.  相似文献   

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Lichens are widely used in biomonitoring studies of air pollution, either as bioindicators of air quality or as bioaccumulators of atmospheric deposition. Over the past decade, several molecular techniques have been developed to provide information on diversity, genotoxicology, genetic relationships, etc. The heavy metal contents of Evernia prunastri samples were determined by atomic absorption spectrometry. The Random Amplified Polymorphic DNA Polymerase Chain Reaction (RAPD-PCR) method was used to describe the pattern of DNA band variation in the samples influenced by the environmental pollution. The study was designed to describe the level of pollution in an area contaminated with smoke and waste from an iron-steel factory, and to reveal the level of potential genotoxic agents around this source of pollution. The study also examined the suitability of the lichen samples for the detection of genotoxicity.  相似文献   

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The air quality in China has improved significantly in the last decade and,correspondingly,the characteristics of PM2.5have also changed.We studied the interannual variation of PM2.5in Chengdu,one of the most heavily polluted megacities in southwest China,during the most polluted season (winter).Our results show that the mass concentrations of PM2.5decreased significantly year-by-year,from 195.8±91.0μg/m3in winter 2016 to 96.1±39.3μg/m3in wi...  相似文献   

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1IntroductionAsoneofthemostimportantsourcesforpowergeneration,coalminingindustryisstilincreasingwithpopulationgrowthandeconom...  相似文献   

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Through shifts toward interactive and participatory forms of environmental governance, knowledge dynamics may come into play that differ from those of traditional forms of policy-making. This paper investigates how shifts of environmental governance and knowledge are related. In order to do so, it reconstructs the development of the governance of recreational boating in the Dutch Wadden Sea on the empirical basis of interviews, document analysis, and a focus group. Moreover, it analyzes this development by means of an analytical framework that combines governance modes, knowledge systems and knowledge–governance interfaces. Our results show that in the last decades partly an accumulation and partly a sequence of various governance arrangements concerning recreational boating has occurred; this has entailed a shift from predominantly centralized governance to a combination of governance modes with a stronger emphasis on decentralized, interactive and self-governance. This shift has occurred together with an increasing prominence of qualitative local knowledge, stakeholders’ knowledge, and the integration of various forms of knowledge. Furthermore, a shift has taken place toward more participatory knowledge–governance interfaces. Our analysis suggests that environmental governance and knowledge are interconnected in various ways: the regulatory and epistemic aspects of environmental issues are bound up with each other, and governance and knowledge are coproduced and mutually constitutive. Key lessons from this analysis are that room for experimentation is an important factor in improving environmental governance, and that increasing stakeholder involvement in governance implies that new modes of jointly creating and exchanging knowledge may need to be taken into account.  相似文献   

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Flood risk management is becoming increasingly important, because more people are settling in flood-prone areas, and flood risk is increasing in many regions due to extreme weather events associated with climate change. It has been proposed that appropriately designed flood risk communication campaigns can stimulate floodplain inhabitants to prepare for flooding, and encourage adaptation to climate change. However, such campaigns do not always result in the desired action, and the effectiveness of communication in raising flood risk awareness and improving flood preparedness has hardly been studied. We evaluate different flood risk communication strategies, using an agent-based modelling approach, which is especially suitable for examining the effect of communication on each individual, and how flood risk communication can propagate through an individual’s social network. Our modelling results show that tailored, people-centred, flood risk communication can be significantly more effective than the common approach of top-down government communication, even when tailored communication reaches fewer individuals. Furthermore, communication on how to protect against floods, in addition to providing information about flood risk, is much more effective than the traditional strategy of communicating only about flood risk. Another main finding is that a person’s social network can have a significant effect on whether or not individuals take protective action. This leads to the recommendation that flood risk communication should aim at exploiting this natural amplifying effect of social networks, for instance, through the use of social media.  相似文献   

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Environmentalfactorsaffectinggrowthofgrasses,herbsandwoodyplantsonasanitarylandfillLanChongyu;WongMinghung(DepartmentofBiolog...  相似文献   

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