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311.
312.
The STRATEGY project (Sustainable Restoration and Long-Term Management of Contaminated Rural, Urban and Industrial Ecosystems) aimed to provide a holistic decision framework for the selection of optimal restoration strategies for the long-term sustainable management of contaminated areas in Western Europe. A critical evaluation was carried out of countermeasures and waste disposal options, from which compendia of state-of-the-art restoration methods were compiled. A decision support system capable of optimising spatially varying restoration strategies, that considered the level of averted dose, costs (including those of waste disposal) and environmental side effects was developed. Appropriate methods of estimating indirect costs associated with side effects and of communicating with stakeholders were identified. The importance of stakeholder consultation at a local level and of ensuring that any response is site and scenario specific were emphasised. A value matrix approach was suggested as a method of addressing social and ethical issues within the decision-making process, and was designed to be compatible with both the countermeasure compendia and the decision support system. The applicability and usefulness of STRATEGY outputs for food production systems in the medium to long term is assessed.  相似文献   
313.
纳米铁为脱氯菌供电降解三氯乙烯实验研究   总被引:3,自引:0,他引:3  
采用一种从氯乙烯污染场址土壤中提取的脱氯菌种(Dehalococcoides spp.)进行三氯乙烯(TCE)降解实验,研究纳米铁厌氧腐蚀产氢为该脱氯菌种提供电子的可能性.结果表明,在甲醇做电子供体时,稀释25倍的菌液[(2.0±0.44)×105 cell/mL)]可以在96 h内将20 mg/L TCE完全降解,并在190 h时有2.706 μmol乙烯产生.而在无甲醇做电子供体时,96 h内只有部分TCE转化为顺二氯乙烯(cisDCE),且190 h时几乎无乙烯产生(0.159 μmol),因此无电子供体时菌液脱氯活动不能维持.但在4 g/L纳米铁腐蚀产氢的情况下,脱氯菌可以利用纳米铁产生的阴极氢维持脱氯活动,在131 h内将20 mg/L TCE完全降解,并且其耦合的脱氯速率高于纳米铁单独降解时的速率.从乙烯的产量分析中可以看出,纳米铁供电时190 h后由脱氯菌产生的乙烯量为1.187 μmol,明显低于甲醇做电子供体时乙烯的产量2.706 μmol,表明纳米铁可能对微生物存在一定的毒性效应.同时反应190 h后乙炔的产量为0.109 μmol,相对低于与纳米铁单独降解TCE时的产量0.161 μmol,说明微生物在无电子供体的情况下,竞争利用了纳米铁与水反应产生的电子导致乙炔的生成量降低.上述结果表明,4 g/L的纳米铁与水反应生成的活性氢可以为脱氯菌提供电子,并维持其脱氯活动,这对纳米铁和脱氯菌耦合应用于地下水的有机氯修复具有重要的实际意义.  相似文献   
314.
Post-Triassic theropod, sauropodomorph, and ornithischian dinosaurs are readily recognized based on the set of traits that typically characterize each of these groups. On the contrary, most of the early members of those lineages lack such specializations, but share a range of generalized traits also seen in more basal dinosauromorphs. Here, we report on a new Late Triassic dinosaur from the Santa Maria Formation of Rio Grande do Sul, southern Brazil. The specimen comprises the disarticulated partial skeleton of a single individual, including most of the skull bones. Based on four phylogenetic analyses, the new dinosaur fits consistently on the sauropodomorph stem, but lacks several typical features of sauropodomorphs, showing dinosaur plesiomorphies together with some neotheropod traits. This is not an exception among basal dinosaurs, the early radiation of which is characterized by a mosaic pattern of character acquisition, resulting in the uncertain phylogenetic placement of various early members of the group.  相似文献   
315.
Gorgonian species may contribute to the three-dimensional seascape in soft bottom-gravel areas, but the information on their biology and ecology is very scarce. The biometry and secondary production of the Mediterranean soft bottom-gravel passive suspension feeder Leptogorgia sarmentosa (Cnidaria: Octocorallia) was studied using photographic monitoring of the primary branches from May 1998 to September 2000. The primary branches observed had a high density of polyps (2.2 ± 0.2 SD polyps mm−1) and a high organic matter content (63.2 ± 9.1 SD %). During the two-year sampling period, there was a net negative growth in 90% of the gorgonian population. The mean loss during the 27-month period was −2.9 ± 0.9 SD cm per branch (5.7 mg C branch−1). However, considering only the initial and final diameters and maximum height in the 27 months elapsed time, the gorgonians showed positive growth, which meant that photographic sampling of single branches was a more appropriate method for gorgonian secondary production monitoring. A water mass anomaly detected in 1999 in the north-western Mediterranean Sea may have been the cause of the net negative growth in L. sarmentosa in the studied area. Partial mortality due to different factors, such as strong currents, predation, disease, etc., could be a common strategy in sessile colonial benthic populations that would facilitate their maintenance even during very stressful circumstances.  相似文献   
316.
A number of significant developments towards the management of psychosocial risks have been achieved at the policy level in the European Union (EU) since the introduction of the 1989 European Commission Council Framework Directive 89/391/EEC on Safety and Health of Workers at Work on which a new EU risk prevention culture has since been established, combining legislation, social dialogue, best practices and building partnerships. However, it has been widely acknowledged that initiatives aiming to promote workers’ health have not had the impact anticipated both by experts and policy makers and the main reason for this has been the gap that exists between policy and practice. This paper discusses the findings from the PRIMA-EF project, a policy-orientated project, which focussed on the development of a European framework for psychosocial risk management at the workplace. In particular, the paper presents the results of an EU stakeholder survey and interviews with EU policy level experts to assess their awareness, understanding and evaluation of the impact of policy initiatives for psychosocial risk management.  相似文献   
317.
Environmental Science and Pollution Research - Trophic transfer and bioaccumulation of trace metals have a profound impact on the structure and function of coastal areas; however, the metal...  相似文献   
318.

The tannery industries generate a solid waste known as tannery sludge, which is composed of organic and inorganic compounds, mainly chromium (Cr). When Cr is not removed from the tannery sludge, this solid waste is metal-rich and its application could affect the soil microorganisms. Alternatively, the composting of the tannery sludge can contribute to decreasing the concentration of Cr in the composted tannery sludge (CTS). However, in some cases, the concentration of Cr remains high in the CTS. During the last 10 years, the Cr-rich CTS has been successively applied in the soil, and its effect on soil microbial properties was verified. Here, we discuss the effect of successive applications of Cr-rich CTS on soil microbes. Interestingly, the findings have shown that successive applications of Cr-rich CTS selected specific soil microbial groups with potential functions. In addition, the studies added a new focus to further research evaluating the potential effect of successive applications of Cr-rich CTS on the rare microbial community.

  相似文献   
319.
In this study, we show that moonmilk subaerial speleothems in Altamira Cave (Spain) consist of a network of fiber calcite crystals and active microbial structures. In Altamira moonmilks, the study of the typology and distribution of fiber crystals, extracellular polymeric substances, and microorganisms allowed us to define the initial stages of fiber crystal formation in recent samples as well as the variations in the microstructural arrangement in more evolved stages. Thus, we have been able to show the existence of a relationship among the different types of fiber crystals and their origins. This allowed us to outline a model that illustrates the different stages of formation of the moonmilk, developed on different substrata, concluding that microbes influence physicochemical precipitation, resulting in a variety of fiber crystal morphologies and sizes.  相似文献   
320.
Environmental Science and Pollution Research - Devices based on lateral flow assay (LFA) have been gaining more and more space in the detection market mainly due to their simplicity, speed, and low...  相似文献   
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