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1.
Systematic environmental screenings are still the exception in South-Eastern Europe. Especially, there is a decisive lack of information concerning the occurrence and behaviour of xenobiotic and toxic compounds like volatile-and non volatile halogenated organics, suppressed by the surrogate AOX, synthetic chelating agents, pesticides, like DDT as well as chlorate in the biosphere. The analysis of soils, waters and firns of a representative area in Bulgaria, the Pirin mountains, indicate a relatively low back ground pollution. The accumulation of the xenobiotics in this high mountain region is recognised to be low. Nevertheless, traces of pesticides and chelating agents like EDTA and NTA in ice (firns) and soils were found. The surrogate AOX should be a parameter, suitable for routine environmental screenings of such areas.  相似文献   
2.
The 2000 BSE Inquiry report points out that the most serious failure of the UK Government was one of risk communication. This paper argues that the government's failure to communicate the risks BSE posed to humans to a large degree can be traced back to a lack of transparency in the first risk assessment by the Southwood Working Party. This lack of transparency ensured that the working party's risk characterization and recommendations were ambiguous and thus hard to interpret. It also meant that uncertainties were not addressed in a satisfactory way. In the recommendations, the attitude to uncertainty was implicit rather than explicit.The risk communication based on the report amplified these flaws. Most importantly, it did not address the uncertainty at all. Apparently, the reason for this was fear of overreaction by the public. However, the result was counter-productive, because the risk communication did not then appear trustworthy. Later risk assessments and risk communication omitted to correct these flaws. Indeed, the fact that, following receipt of new information, advisory experts and policy makers had changed their views of the risk to humans was never clearly communicated to the public. There seemed to be little faith in the public's ability to reach a balanced judgment regarding the uncertainties.In the concluding section of the paper, this analysis is compared with the food standards agency's (FSA's) approach to BSE. The intervention of this agency was seen as one of the more important efforts to restore consumer confidence in British beef. And the agency certainly appears to be committed to openness and to addressing scientific uncertainty. However, using the risk of BSE in sheep as a case study, the paper shows that transparency – i.e., the clear presentation of factual and normative claims and assumptions underlying advice, and openness about the reasoning based on these claims and assumptions – is less than fully achieved in the FSA's work.  相似文献   
3.
Saturated-unsaturated flow in strictly layered sediments proceeds via conductors in parallel in the direction parallel to bedding, and via resistors in series in the direction perpendicular to bedding. On sufficiently small scales of space and time, flow in such media will be subject to approximate capillary equilibrium locally, which provides a basis for approximating the effective hydraulic conductivity of a composite multi-layer medium in terms of the conductivities of the individual layers. Equations for the hydraulic conductivity tensor in "composite medium approximation" (COMA) are given in a coordinate system aligned with bedding. Hydraulic conductivity parallel to bedding is generally larger than in the perpendicular direction. The anisotropy depends on the spread of the conductivity distribution, and tends to increase for dryer conditions. The COMA model was implemented in a multi-phase flow simulator and tested by comparison with high-resolution simulations in which all layering heterogeneity is resolved explicitly. Under favorable conditions, COMA is found to accurately represent sub-grid scale flow and transport processes, providing a practical method for simulating field-scale flow and transport in layered media. The approximation improves when layers are thinner, and when flow rates are smaller.  相似文献   
4.
Natural analogues allow scientists to investigate biogeochemical processes relevant to radioactive waste disposal that occur on time scales longer than those that may be studied by time-limited laboratory experiments. The Palmottu U-Th deposit in Finland and the Bangombé natural nuclear reactor in Gabon involve the study of natural uranium, and are both considered natural analogues for subsurface radioactive waste disposal. The microbial population naturally present in groundwater may affect the redox conditions, and hence, the radionuclide solubility and migration. Therefore, groundwater samples from the two sites were investigated for microbial populations. The total numbers of cells ranged from 10(4) to 10(6) cells ml(-1). Iron-reducing bacteria (IRB) were the largest culturable microbial population in the Palmottu groundwater and were present at up to 1.3 x 10(5) cells ml(-1). Sulfate-reducing bacteria (SRB) and acetogens could also be cultured from the Palmottu groundwater. The numbers of IRB and SRB were largest in groundwater with the lowest uranium concentrations. Removal of dissolved U(VI) from solution was concomitant with the growth of IRB enrichment cultures and the reduction of iron. The redox buffer in the Palmottu groundwater consists of iron and uranium species, both of which are affected by IRB. IRB and aerobic heterotrophs were cultured from the Bangombé groundwater, where redox potentials are buffered by iron and organic carbon species. Microbial populations similar to those found at Palmottu and Bangombé are found throughout the Fennoscandian Shield, a potential host rock for subsurface radioactive waste disposal. These results confirm that microorganisms can be expected to play a role in stabilizing radioactive waste disposed of in the subsurface by lowering redox potential and immobilizing radionuclides.  相似文献   
5.
6.
This paper focusses on a conceptual overview of ways to address a comprehensive analysis of ecosystem services (ES) in a country as large and heterogeneous as Russia. As a first step, a methodology for assessing the services for the federal subjects of Russia was chosen, i.e., its constituent provinces and similar entities, in physical terms. Russia harbors a great diversity of natural conditions and ecosystems which are suppliers of ES, and likewise a variety of the socio-economic conditions that shape the demand for these services and their consumption. The methodological approach described permits several important tasks to be addressed: the evaluation of the degree of satisfaction of people’s needs for ES, the identification of ecological donor and acceptor regions, and zoning of the country’s territory for ES assessment. The next step is to prepare a prototype of a National Report on ES in Russia, for which we are presenting the planned structure.  相似文献   
7.
Marie Jahoda's latent deprivation model was tested with a representative sample of the German population (N = 998). As expected, employees reported high levels of time structure, social contact, collective purpose, and activity not only in comparison to unemployed persons but also in comparison to persons who are out of the labor force (i.e., students, homemakers, retirees). Even unskilled manual workers reported more access to these “latent functions” than persons without employment. For the fifth of Jahoda's dimensions, identity/status, no significant differences between employed persons and persons who are out of the labor force could be identified. However, unemployed persons reported less status than all other groups did. Thus, Jahoda's model was clearly endorsed for four of the five latent functions of employment and partly endorsed for the fifth function. All variables in the model correlated significantly with distress, as expected. Demographic correlates of the manifest and latent functions were also analyzed: Access to the latent functions was best among young men from higher social classes who lived in an intimate relationship in a comparatively large household with children. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
8.
During the last 40 years, merchant ships have become safer and a number of new safety measures have been introduced. The purpose of the first part of this study was to investigate the trend of fatalities due to maritime disasters in the Danish merchant fleet over a 40-year period from 1970 to 2009, during which a total of 146 seafarers lost their lives. The relative risk of fatal accidents in the period 1990–2009 compared with the period 1970–1989 was 0.81 (CI: 0.58–1.14).The second part of the study focuses on seafarers who abandoned a merchant ship in the period from 1990 to 2009. The purpose was to investigate factors influencing survival. During the 20-year period 44 incidents were identified involving a total of 267 seafarers. Among these, 51 did not survive. The fatality risk for seafarers on small and large ships was 3.68 and 0.64 per 1000 years at risk, respectively. Among the 171 seafarers who were rescued dry, one was injured and did not survive (0.6%). Out of 64 seafarers ending up in the water, 18 (28%) did not survive. Among the remaining 32 seafarers, 23 were with great certainty inside the vessel when it sank and another nine may have remained inside the sinking vessel. None of these survived. Suboptimal organisation of the evacuation process was of importance in some cases. Survival suits and automatic emergency transmitters (EPIRB’s) have been shown to work in practice but their introduction has had limited influence on survival statistics.  相似文献   
9.
10.

Objective

Flood sediments were investigated due to the extreme flood situation around Dresden in August 2002

Method

The samples have been analyzed by screening inorganic and organic pollutants.

Results

It was observed that As, Pb, Cd, Zn, Cu, B and other heavy metals as well as DDT, PCB and Benzo [a] pyren were significantly enriched.

Conclusion

Depending on geogenic and anthropogenic impacts, the spatial distribution of these contaminants was different. Organic compounds were dislocated down stream from Czech Republic along the Elbe River. Because of the old ore mining, samples near the Mulde and Wei\eritz Rivers showed high metal pollution.

Perspective

More detailed and systematic investigations should be undertaken in the Elbe and Mulde river systems.  相似文献   
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