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1.
Today, radioecology covers a broad scientific field; from the source to long term environmental impact from ionizing radiation. To summarize key challenges within radioecology, the present paper focuses upon knowledge gaps related to processes, mechanisms and variables contributing most to the overall uncertainties in environmental impact assessments. A series of sources related to the nuclear weapon cycle and the civil nuclear cycle has contributed, is still contributing or can potentially contribute to release of radionuclides to the environment in the future. The speciation of most radionuclides depends on the source and release conditions, and will influence ecosystem transport, biological uptake, doses and effects in flora and fauna. Radionuclides may also co-occur in contaminant mixtures (e.g., metals, organics), which potentially could lead to synergisms or antagonisms. Thus, challenges associated with the links between the source or release term – radionuclide speciation – ecosystem transfer – exposure – response relationships are highlighted.  相似文献   

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If no data are available for a specific radionuclide its analogue could be used in radioecological models. They might be used not only in the frame of screening modelling. Relevant processes and features have to be known, such as time scales of these processes, physical, chemical and biological properties of the environment and relevant media. An analogue could only be proven to be valid by comparing its behaviour in the conditions of interest, while confidence in the validity of an analogue will increase as the quality of the justification increases, there will always be some residual uncertainty. Several main types of analogy can be used when measured or recommended values are not available: the same parameter obtained for another isotope of the same element; the same parameter obtained for another element; a different parameter obtained for the same element. There are several cases, when analogues might be applied as indicators of the determining processes in the radioecological studies.  相似文献   

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This paper presents a review of the current status of radioecology and how it might be applied to contribute to a broader range of environmental pollution and contamination problems. In many respects radioecology is a unique and specialised branch of environmental science. However, radioecologists could be much more aware of the similarities and differences between their field and other fields of environmental pollution science. Areas of common interest described herein are exposure and risk assessment, and the problem of the bioavailability of potentially toxic substances in environmental media. It is concluded that radiometric methods and radioecological modelling methods can assist significantly with understanding and quantifying both these issues. The existence of multiple contaminants at many locations around the world dictates that assessment and remediation exercises should be carried out in an integrated fashion, as a partnership between scientific disciplines.  相似文献   

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The first significant quantities of artificial radioactivity appeared in the environment around the end of the 1940s. They were gigantic and their metrology very quickly seemed to be essential for sanitary and military reasons. In the 1950s, the first continuous monitoring systems of "fall out" were created. They were neither automatic nor sensitive and radioprotection of the environment was not a concern only for simple public information. Since then, radioecology, technology and evolution of our mentality have completely modified our way of thinking. Thus, from the 1980s up to the dawn of the new millennium, the gap between the performances of metrology laboratories and certain aspects of direct measurement has almost disappeared. 1986 certainly contributed a lot to the concept of surveillance networks and alarm systems, emphasising that the major advantage of these is the fact that they are operational, the minute before the accident.  相似文献   

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Cosmogenic (10)Be, known for use in dating studies, unexpectedly is also produced in nuclear explosions with an atom yield almost comparable to (e.g.) (137)Cs. There are major production routes via (13)C(n, alpha)(10)Be, from carbon dioxide in the air and the organic explosives, possibly from other bomb components and to a minor extent from the direct fission reaction. Although the detailed bomb components are speculative, carbon was certainly present in the explosives and an order of magnitude calculation is possible. The (n, alpha) cross-section was determined by irradiating graphite in a nuclear reactor, and the resulting (10)Be estimated by Accelerator Mass Spectrometry (AMS) giving a cross-section of 34.5+/-0.7mb (6-9.3MeV), within error of previous work. (10)Be should have applications in forensic radioecology. Historical environmental samples from Hiroshima, and Semipalatinsk (Kazakhstan) showed two to threefold (10)Be excesses compared with the background cosmogenic levels. A sample from Lake Chagan (a Soviet nuclear cratering experiment) contained more (10)Be than previously reported soils. (10)Be may be useful for measuring the fast neutron dose near the Hiroshima bomb hypocenter at neutron energies double those previously available.  相似文献   

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The 2007 Recommendations of the International Commission on Radiological Protection (ICRP) represent a change from a process-based to an exposure-based approach, where exposure situations are categorised as planned, emergency, and existing exposure situations. Although the new Recommendations contain further changes based on, inter alia, scientific developments since the publication of the 1990 Recommendations, they overall represent more continuity than change – a notable exception being the direct consideration of environmental protection. The implications of the new Recommendations for radioactive waste management are fairly marginal, as earlier recommendations in this area are still considered valid. This communication provides a brief overview of the current ICRP system for radiological protection as applied to radioactive waste management, as well as an outlook including the possibility of using the developing ICRP system for management of environmental effects as an ‘alternative way of reasoning’ when building the safety case for a specific waste disposal concept.  相似文献   

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The history of problems dealing with competing risks is briefly outlined, beginning with Daniel Bernoulli's 1760 “Mémoir” on mortality due to smallpox and proceeding through the development of actuarial techniques and methods used in clinical research, reliability theory, population dynamics, and other areas of application. A probabilistic formulation of the theory of competing risks is then presented which appears applicable to all these areas. Within the framework of this theory, some fundamental problems are stated and discussed, such as questions of identifiability, choices of estimation procedures, or techniques for testing hypotheses.  相似文献   

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The EU Water Framework Directive (WFD) is novel because it integrates water quality, water resources, physical habitat and, to some extent, flooding for all surface and groundwaters and takes forward river basin management. However, the WFD does not explicitly mention risks posed by climate change to the achievement of its environmental objectives. This is despite the fact that the time scale for the implementation process and achieving particular objectives extends into the 2020s, when climate models project changes in average temperature and precipitation. This paper begins by reviewing the latest UK climate change scenarios and the wider policy and science context of the WFD. We then examine the potential risks of climate change to key phases of the River Basin Management Process that underpin the WFD (such as characterisation of river basins and their water bodies, risk assessments to identify pressures and impacts, programmes of measures (POMs) options appraisal, monitoring and modelling, policy and management activities). Despite these risks the WFD could link new policy and participative mechanisms (being established for the River Basin Management Plans) to the emerging framework of national and regional climate change adaptation policy. The risks are identified with a view to informing policy opportunities, objective setting, adaptation strategies and the research agenda. Key knowledge gaps have already been identified during the implementation of the WFD, such as the links between hydromorphology and ecosystem status, but the overarching importance of linking climate change to these considerations needs to be highlighted. The next generation of (probabilistic) climate change scenarios will present new opportunities and challenges for risk analysis and policy-making.  相似文献   

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The complex relationships between governance processes, ecosystem management and biodiversity conservation are receiving growing attention by the scientific community. The scope of research in this field is generally that of identifying main governance factors leading to success or failure in the sustainable management of ecosystems and biodiversity conservation, so to develop appropriate sectoral and intersectoral policies fostering sustainable use of natural resources. In this paper, a methodological approach is first presented and then applied to analyse the impacts of agriculture and rural policies on agro-ecosystem services and biodiversity conservation in the central hills of Tuscany, the Chianti area. This approach is focusing in particular on governance objectives and instruments used in the management of ecosystem services. A share-farming system based on multifunctional agriculture ruled Chianti until World War II. Then, after the abandonment of rural areas by share-farmers, governance objectives and ecosystem management were oriented towards the production of commodities such as wine and olive oil almost ignoring the provision of public goods such as soil erosion and water run-off control and biodiversity conservation. In order to achieve a more sustainable ecosystems management in Chianti, there is the need to develop a multifaceted governance strategy to reward appropriately the supplying of environmental goods and services by farmers.  相似文献   

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新冠肺炎疫情的发生暴露了我国野生动物保护立法在禁止食用野生动物源头制度设计上的不足,引发了社会舆论对“全面禁止食用野生动物”的强烈呼吁。审视我国《野生动物保护法》,立法目的理念中并没有体现保障公众健康的内容;对捕食野生动物没有采取完全禁止的态度,而是根据野生动物的珍稀、濒危程度,生态、科学、社会价值,以及是否为人工繁育等多重标准,分别采取了禁止食用、限制食用、特别许可、支持利用等不同的措施,存在失之过宽的问题;野生动物保护范围不周延,一些可能引发疫病传播的野生动物没有纳入保护范围。回应社会关切,对立法中存在的问题进行理性分析,应当尽快修改《野生动物保护法》,矫正立法目的理念,体现对公众健康安全的保障;扩大野生动物的保护范围,并制定相应的管制规范;实现相关立法的衔接,建立以“全面禁止食用为原则,分类限制禁止食用为补充”的野生动物风险防范制度。从源头上防范野生动物病毒传播引发重大公共卫生风险,实现保护野生动物与保障公众健康安全的有机统一。  相似文献   

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Employees in six day-care institutions were asked to fill out a simple questionnaire before and one year after technical changes were made in their buildings. The institution were defined as sick buildings, based on a prevalence (exceeding 40%) of irritative symptoms and general symptoms among the employees. Based on the technical measurements there were no obvious reasons for the complaints. It was decided, however, to remove man-made mineral-acoustic ceilings and to install mechanical ventilation. One year later there was a significant reduction in the prevalence of symptoms (irritative and general symptoms related to the sick building syndrome) among the employees. The study indicates that systematic monitoring of employees' symptoms before and after corrective action is an important indicator of the benefit of the actions and might be used routinely by architects, engineers, and local authorities in dealing with indoor climate problems. Follow-up studies might give more knowledge of the causes of sick building syndrome.  相似文献   

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A pilot field study was conducted with nine members of the general public to measure carbon monoxide exposure using personal monitors. The principal study objectives were to design and evaluate the research protocol and the instrumentation performance for application to the conduct of a large-scale personal monitoring program. Integrated carbon monoxide exposure was monitored and recorded according to type of activity such as “commuting” or “at work” for approximately 45 days by each subject. All subjects except one were able to handle both the equipment and data recording requirements with no significant problems. Actual data recording responsibilities consumed less than 10 min daily. The data consisted of 355 person-days each over 6-h duration, and weekdays only, from which 8-h average personal exposure levels could be computed. The 9 ppm (μL/L) ambient air quality standard was exceeded on 22 person-days. Elevated carbon monoxide concentrations during the commuting activity were frequently associated with the exceedences.  相似文献   

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Sewage sludge and manure are common soil amendments in crop production; however, their impact on the abundance and diversity of the antibiotic resistome in soil remains elusive. In this study, by using high-throughput sequencing and high-throughput quantitative PCR, the patterns of bacterial community and antibiotic resistance genes (ARGs) in a long-term field experiment were investigated to gain insights into these impacts. A total of 130 unique ARGs and 5 mobile genetic elements (MGEs) were detected and the long-term application of sewage sludge and chicken manure significantly increased the abundance and diversity of ARGs in the soil. Genes conferring resistance to beta-lactams, tetracyclines, and multiple drugs were dominant in the samples. Sewage sludge or chicken manure applications caused significant enrichment of 108 unique ARGs and MGEs with a maximum enrichment of up to 3845 folds for mexF. The enrichment of MGEs suggested that the application of sewage sludge or manure may accelerate the dissemination of ARGs in soil through horizontal gene transfer (HGT). Based on the co-occurrence pattern of ARGs subtypes revealed by network analysis, aacC, oprD and mphA-02, were proposed to be potential indicators for quantitative estimation of the co-occurring ARGs subtypes abundance by power functions. The application of sewage sludge and manure resulted in significant increase of bacterial diversity in soil, Proteobacteria, Acidobacteria, Actinobacteria and Chloroflexi were the dominant phyla (> 10% in each sample). Five bacterial phyla (Chloroflexi, Planctomycetes, Firmicutes, Gemmatimonadetes and Bacteroidetes) were found to be significantly correlated with the ARGs in soil. Mantel test and variation partitioning analysis (VPA) suggested that bacterial community shifts, rather than MGEs, is the major driver shaping the antibiotic resistome. Additionally, the co-occurrence pattern between ARGs and microbial taxa revealed by network analysis indicated that four bacterial families might be potential hosts of ARGs. These results may shed light on the mechanism underlining the effects of amendments of sewage sludge or manure on the occurrence and dissemination of ARGs in soil.  相似文献   

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Heavy metal accumulation by plant communities has been studied in different zones of impact of gas field development. The contents of heavy metals in different blocks of plant communities has proved to depend not only on the location of phytocenosis but also on its species composition. Communities dominated by species of the family Poaceae contain smaller amounts of heavy metals than those dominated by species of the family Asteraceae, especially of the genus Artemisia. The order of precedence in the accumulation of heavy metals in different blocks of plant communities has been revealed.  相似文献   

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The results of radiometric and haematological studies of striped field mice (Apodemus agrarius) sampled over the years 1995-2003 from the territory of the preserved radioactive waste burial (RWB), which is located in the Moscow recreation forest "Kuzminki", are presented and discussed in the paper. It was shown that the level of 90Sr-90Y content in mice sampled from the RWB area varies within the range of 0-1200 Bq/kg with an average of 98.7+/-21.5 Bq/kg. The content of 90Sr-90Y in the body of 80% of the mice sampled from the RWB area was below 100 Bq/kg. Only in 4% of the sampled mice, the 90Sr-90Y specific radioactivity was above 300 Bq/kg. Haematological indications of the animals sampled from the RWB area were within the range of normal physiological fluctuations. Nevertheless, a slight but statistically significant increase in the average amount of erythrocytes and the average percentage of banded neutrophils was registered in peripheral blood of the mice.  相似文献   

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“天人合一”是中国古代思想家对于天人关系的基本认识,主张遵循自然规律.实现人和自然的和谐发展.这一思想对于生态保护与天人关系的协调发展具有重要意义。经济全球化时代。探寻“天人合一”向“天人和谐”可持续发展观的现代性转化的途径,将有助于我们重瓤认识自然,正确把握环境保护与经济发展的辩证关系,培养人类的道德责任意识及科学实践精神,为现代生态伦理学的建立和可持续发展战略的实施提供帮助。  相似文献   

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