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我从路华汽车里小心翼翼地滑出来,带着大型摄影机以及各式各样的器材,这可不是件容易的事。  相似文献   
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本研究的目标是增加关于模型生成数据被用作水质管理的交流工具时,地方利益相关者接受该数据的知识.研究地区选在瑞典西南部的伦讷(R(o)nne(a))河流域.结果表明,模型生成数据起到了联合因素的作用.同时,利益相关者与提供的数据有关,主要问题为未考虑到的污染源、测定污染时缺乏信任、自然变化和延迟效应的影响的不确定性.确定了4组影响利益相关者接受模型生成数据的因素对其实际应用的信心,对所涉及的参与人员或对话资料提供者(如专家、决策者、媒体)的信心,参与者的社会特征(如年龄和职业),和数据的交流方式(如交流的语气、小组的构成、持续时间、对话的地理尺度).对给定的模型生成数据实际应用的公平性的感知,也是接受与否的一个重要因素.  相似文献   
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Medium-chain acyl-CoA dehydrogenase (MCAD) deficiency is a potentially fatal inherited disease with a carrier frequency of approximately 1:100 in most Caucasian populations. The disease is implicated in sudden unexpected death in childhood. A prevalent disease-causing point mutation (A985G) in the MCAD gene has been characterized, thus rendering diagnosis easy in the majority of cases. Since the clinical spectrum of MCAD deficiency ranges from death in the first days of life to an asymptomatic life, there are probably other genetic factors—in addition to MCAD mutations—involved in the expression of the disease. Thus, families who have experienced the death of a child from MCAD deficiency might have an increased risk of a seriously affected subsequent child. In such a family we have therefore performed a prenatal diagnosis on a chorionic villus sample by a highly specific and sensitive polymerase chain reaction (PCR) assay for the G985 mutation. The analysis was positive and resulted in abortion. We verified the diagnosis by direct analysis on blood spots and other tissue material from the aborted fetus and from family members.  相似文献   
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Environmental Science and Pollution Research - The aim of the study was to determine if gold-mining activities could impact the mercury (Hg) concentrations and isotopic signatures in freshwater...  相似文献   
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The aim of the study, on which this paper is based, was to provide guidance to consumers to make environmentally responsible choices in their food consumption, to assist food supply chain stakeholders to identify the key areas for environmental improvements, and to provide policy makers with a tool for monitoring the potential impacts on climate change resulting from developments within the food sector. At the macro level, the EIO-LCA model was developed specifically for the Finnish food chain; at the micro level, LCAs were performed on 30 lunch portions. The contribution of the Finnish food chain to climate change was 14%, which comprised 40% CO2 emissions, 25% CH4 emissions, and 34% N2O emissions. The share of impacts from domestic agricultural processes was the highest, at 69%. The impact of a single lunch portion ranged between 0.65 and 3.80 kg of equivalent CO2. According to the EIO-LCA model, the average impact was 7.7 kg CO2 eq/person daily. The consumer phase accounted for between 8 and 47% of the climate change impacts for homemade portions. In ready-to-eat portions industry and retail phases were emphasized, representing 25-38% of climate change impacts. We present an approach to steer the Finnish food sector onto an environmentally sustainable path; practical tools for consumers and farmers will especially need to be developed further.  相似文献   
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Ambio - The choice of tree species used in production forests matters for biodiversity and ecosystem services. In Sweden, damage to young production forests by large browsing herbivores is helping...  相似文献   
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Ion-exchange resins (IER) offer alternative approaches to measuring ionic movement in soils that may have advantages over traditional approaches in some settings, but more information is needed to understand how IER compare with traditional methods of measurement in forested ecosystems. At the Bear Brook Watershed in Maine (BBWM), one of two paired, forested watersheds is treated bi-monthly with S and N (28.8 and 25.2kgha−1yr−1 of S and N, respectively). Both IER and ceramic cup tension lysimeters were used to study soil solution responses after ∼11 years of treatment. Results from both methods showed treatments resulted in the mobilization of base cations and Al, and higher SO4—S and inorganic N in the treated watershed. Both methods indicated similar differences in results associated with forest type (hardwoods versus softwoods), a result of differences in litter quality and atmospheric aerosol interception capacity. The correlation between lysimeter and IER data for individual analytes varied greatly. Significant correlations were evident for Na (r=0.75), Al (r=0.65), Mn (r=0.61), Fe (r=0.57), Ca (r=0.49), K (r=0.41) and NO3—N (r=0.59). No correlation was evident between IER and soil solution data for NH4—N and Pb. Both IER and soil solution techniques suggested similar interpretations of biogeochemical behavior in the watershed.  相似文献   
9.

The aim of this study was to determine the bioavailability of metals in field soils contaminated with chromated copper arsenate (CCA) mixtures. The uptake and elimination kinetics of chromium, copper, and arsenic were assessed in the earthworm Eisenia andrei exposed to soils from a gradient of CCA wood preservative contamination near Hartola, Finland. In soils contaminated with 1480–1590 mg Cr/kg dry soil, 642–791 mg Cu/kg dry soil, and 850–2810 mg Ag/kg dry soil, uptake and elimination kinetics patterns were similar for Cr and Cu. Both metals were rapidly taken up and rapidly excreted by Eisenia andrei with equilibrium reached within 1 day. The metalloid As, however, showed very slow uptake and elimination in the earthworms and body concentrations did not reach equilibrium within 21 days. Bioaccumulation factors (BAF) were low for Cu and Cr (< 0.1), but high for As at 0.54–1.8. The potential risk of CCA exposure for the terrestrial ecosystem therefore is mainly due to As.

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10.
In a laboratory study we investigated 1) the potential production of nitrous oxide (N2O), methane (CH4) and carbon dioxide (CO2) and 2) the effect of nitrate (NO3?) and anaerobic N2O development on CH4 production in sediment from a recently recreated free surface water wetland (FSWW) and in soil from an adjacent meadow. We designed an experiment where production of greenhouse gases was registered at the time of maximum net development of N2O. We made additions of biodegradable carbon (glucose) and/or NO3? to sediment and soil slurries and incubated them at four temperatures (4, 13, 20, 28 °C). Gas production from both substrates was positively correlated with temperature. We also found that the sediment produced more N2O than the soil. N2O production in sediment was NO3? limited, whereas in soil carbon availability was lower and only combined additions of NO3? and glucose supported increased N2O development. CH4 production was generally low and did not differ between soil and sediment. Nor did glucose addition increase CH4 rates. The results suggest that neither soil nor sediment environment did support development of methanogenic populations. There were no clear effects of NO3? on CH4 production. However, the highest records of CH4 were found in incubations with low N2O production, which indicates that N2O might be toxic to methanogens. In summary, our study showed that transforming meadows into FSWWs implies a risk of increased N2O emissions. This does not seem to be valid for CH4. However, since N2O is almost always produced wherever NO3? is denitrified, increased N2O production in wetlands leads to reduced rates in downstream environments. Hence, we conclude that when balancing NO3? retention and global warming aspects, we find no reason to discourage future creation or restoration of wetlands.  相似文献   
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