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891.
S. Fesenko N. Isamov B.J. Howard N.A. Beresford C.L. Barnett N. Sanzharova G. Voigt 《Journal of environmental radioactivity》2009
Over 150 publications reporting studies conducted in the former USSR were reviewed to provide transfer coefficients (Ff) to the muscle of domestic animals from experiments using chronic administration, often for long timescales in large scale experiments. Only a few of these studies were made available in the English language literature or taken into account in international reviews. The values derived have been compared with expected values reported by the IAEA's Handbook of parameter values for the prediction of radionuclide transfer in temperate environments (TRS 364) where possible. The information presented here has been used in the current updating of parameters recommended for environmental assessments by the IAEA. Many of the reported values are for Sr due to the Mayak accident and Cs due to the Chernobyl accident. Nevertheless, the reported data for a wide range of radionuclides, in particular for Ru, Sb, and Zn markedly improve the extent of available data. 相似文献
892.
S.J. Sartandel S.K. Jha S.V. Bara R.M. Tripathi V.D. Puranik 《Journal of environmental radioactivity》2009,100(10):831-834
The understanding and evaluation of the possible interactions of various naturally occurring radionuclides in the world's third largest man-made dam, Nagarjuna Sagar located in Andhra Pradesh, India and built on river Krishna assumed significance with the finding of uranium deposits in locations near the dam. For the present work, surface soil samples from the mineralized area of Lambapur, Mallapuram, Peddagattu and sediment core samples from the Nagarjuna Sagar dam were analyzed for naturally occurring radionuclides namely uranium and thorium using gamma spectrometric technique. Also toxic elements lead and chromium were analysed by the Energy Dispersive X-ray Fluorescence Spectrometer (EDXRF) technique. Surface soil samples show a variation from 25 to 291 Bq/kg (2.02–23.5 mg/kg) for 238U and 32–311 Bq/kg (7.9–76.9 mg/kg) for 232Th. U/Th concentration ratio in surface soil samples ranged from 0.19 to 0.31 and was found comparable with the nation wise average of 0.26. The study of sediment core samples reflected higher U/Th concentration ratio of 0.30–0.33 in the bottom section of the core as compared to 0.22–0.25 in the upper section. The concentration ratio in the upper section of the core was similar to the ratio 0.23 found in the western Deccan Basalt region through which the river originates. A higher concentration of lead and chromium was observed in the upper section of the core compared to bottom section indicating the impact of river input on the geochemical character of dam sediment. 相似文献
893.
The system of radiological protection of the environment that is currently under development is one contribution to the general need to adequately protect the environment against stress. Dominated by operational goals, it emphasizes conceptual and methodological approaches that are readily accessible today: reference organisms supported by individual-based traditional ecotoxicological data. Whilst there are immediate advantages to this approach (pragmatism, consistency with other approaches in use for man and biota), there are also clear limitations, especially in a longer run perspective, that need to be acknowledged and further considered. One can mention a few: uncertainties generated by the need for various extrapolations (from lower to higher levels of biological organisation, …), various features missed such as potential ecological impact through impairment of ecosystem processes, trans-generational impacts as mediated through genomic instability, indirect effects mediated through trophic interactions or disruption of ecological balances,… Such limitations have already been faced in other fields of environmental protection against other stressors, pushing a number of environment professionals to assign stronger emphasis on more systemic approaches. This review discusses the advantages and limitations of the current approach designed for the radiological protection of non-human biota in the broader context of environment protection as a whole, with especial reference to upcoming trends and evolutions. This leads in particular to advocating the need to boost scientific and methodological approaches featuring the ecosystem concept as a mean to access a unified goal of protection: preserving life sustainability through protection of ecosystem structure and functioning. 相似文献
894.
A framework for the protection of the general public has been in existence for a very long time, although steps have recently been made by the ICRP to ensure that it is more fully comprehensive with regard to all actual and potential exposure situations. Protection of the environment, however, has only recently begun to be addressed in a structured manner, and is still an evolving subject. Nevertheless, it needs to be centred around some form of parallel framework to that which has evolved for the protection of human beings, although clearly on a different scale. It also needs to be embedded within the basic science of radiobiology, and form a central part of radioecology. 相似文献
895.
Environmental sociology and the sociology of natural resources are two key subdisciplines of the sociological study on the interactions between nature and human society. Previous discussion on the relationships of these two fields has largely focused on their distinctions and synthesis in western (particularly American) academia. Environmental sociology emerged as an important sociological subdiscipline in China in the early 1990s and is under vigorous disciplinary construction at present. By contrast, the sociology of natural resources is still a novel term for most Chinese researchers. This article provides a systematic review of recent literature on the relationships between environmental and natural resource sociologies, which should provide important implications for the further development of environmental sociology in China. 相似文献
896.
The results of monitoring the dates of the onset of flowering and leaf budding in eight herbaceous and woody plant species and the first appearance of three insect species in the Il’men Reserve (1972–2005) were processed by means of regression and correlation analyses. No significant changes in test parameters were revealed in the majority of these species. Only two early spring plants, coltsfoot (Tussilago farfara L.) and goat willow (Salix caprea L.), showed a weak tendency toward earlier flowering in the 1980s and 1990s. This is explained primarily by the absence of any significant trends in spring and summer air temperatures in the study region over the observation period. On the other hand, interannual fluctuations in the dates of plant flowering and insect appearance were well manifested not only in early spring but also in late-spring species. These fluctuations proved to depend largely on spring temperatures: in years with early and warm springs, flowering and leaf budding in plants and the appearance of first individuals in insects were recorded on significantly earlier dates. 相似文献
897.
The results of studies on postfire succession in larch forests of the permafrost zone are discussed. The main directions of successional processes in burned-out areas of different ages are described. It has been shown that secondary pyrogenic successions in larch forests follow the scheme of rapid regeneration without tree species replacement and the model of succession tolerance. Groups of plant species with different life strategies and indicator species characterizing different stages of the overgrowing of burned-out areas have been identified. 相似文献
898.
899.
Anna Rabinovich Thomas A. Morton Tom Postmes Bas Verplanken 《Journal of environmental psychology》2009
This paper investigated the effect of goal and mindset specificity on goal-related behavior in the environmental domain. Two studies demonstrated that goal-related behavior was maximized when participants focused on an abstract goal in combination with a specific mindset, or when they focused on a specific goal in combination with an abstract mindset. When goals and mindsets instead matched in terms of abstractness, goal-related behavior was reduced. Study 2 demonstrated that the effect of goal specificity on behavior was mediated by different processes in each of the mindset conditions. When mindsets were abstract, self-efficacy mediated the positive effect of specific goals on behavior; when mindsets were specific, the value of collective environmental action mediated the positive effect of abstract goals on behavior. The results are discussed in the framework of a complementarity approach. It is argued that complementarity of levels of specificity of goals and mindsets may affect behavior particularly strongly in domains where the discrepancy between the abstract and the specific is large (e.g. the environmental domain). 相似文献
900.
Kelley L. Arbogast Brian C.P. Kane Jeffrey L. Kirwan Bradley R. Hertel 《Journal of environmental psychology》2009
Empirical and anecdotal evidence suggests that landscapes with more vegetation have a positive impact on children's focus, attention, and cognitive development. In school, children are able to regain focus, suppress impulses, and pay attention in class longer after exposure to natural settings. Because children spend much of their time in school, the amount and types of vegetation on school grounds may influence their development. Public elementary schools in the Commonwealth of Virginia (N = 988) were surveyed to examine correlations between school ground vegetation and outside recess. The number of trees on school grounds, the size of the school grounds, and the presence of sports fields were modestly correlated with greater outside recess time. These correlations support common sense because sports fields facilitate supervised play and larger school grounds provide space for sports fields and playgrounds and additional opportunities for free play. More trees on school grounds provide a welcoming environment for students and teachers, and encourage outside play. These results may help school personnel design and maintain school grounds that increase outdoor recess time. 相似文献