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1.
The feasibility of including sustainability in LCA for product development   总被引:1,自引:0,他引:1  
The feasibility of combining the concept of sustainability principles and the methodology of Life Cycle Assessment (LCA) is examined. The goal is to achieve an operational tool that incorporates sustainability in product development and strategic planning. While the method outlined has the structure of LCA, it emphasises aspects and parameters often omitted from traditional LCA. The analysis and results can be either qualitative or semi-quantitative. Although a qualitative analysis is less time consuming, it can still highlight the important issues. Qualitative information, which is easily lost in a quantitative analysis, can be emphasised. One of the conclusions is that the method is well suited for screening analysis.  相似文献   
2.
In this study a method is suggested to compare the net carbon dioxide (CO2) emission from the construction of concrete- and wood-framed buildings. The method is then applied to two buildings in Sweden and Finland constructed with wood frames, compared with functionally equivalent buildings constructed with concrete frames. Carbon accounting includes: emissions due to fossil fuel use in the production of building materials; the replacement of fossil fuels by biomass residues from logging, wood processing, construction and demolition; carbon stock changes in forests and buildings; and cement process reactions. The results show that wood-framed construction requires less energy, and emits less CO2 to the atmosphere, than concrete-framed construction. The lifecycle emission difference between the wood- and concrete-framed buildings ranges from 30 to 130 kg C per m2 of floor area. Hence, a net reduction of CO2 emission can be obtained by increasing the proportion of wood-based building materials, relative to concrete materials. The benefits would be greatest if the biomass residues resulting from the production of the wood building materials were fully used in energy supply systems. The carbon mitigation efficiency, expressed in terms of biomass used per unit of reduced carbon emission, is considerably better if the wood is used to replace concrete building material than if the wood is used directly as biofuel.  相似文献   
3.
本文表明农场主之间的联合经营体(partnership arrangements)可能是保障农场经济生存能力和提高效益的途径之一.本文讨论了三种不同协作类型的经验分析,并强调了与协作经营关联的环境改善.在第一个案例中,对牛奶场和种植农场的协作进行了分析,结果表明多样化的提高和轮作具有实质的潜在效益,当协作包括机械时,其潜在效益更高.第二个例子论及生猪育崽和精饲管理的外部综合条件.协作利润源于生物因子和技术因子两方面,诸如提高生长率和增加猪舍的利用率等.最后,本文对一组种植农场协作进行了评估,认为效益的增加主要得益于机械费用的减少和/或来自其它因素的收益,如轮作和管理、营销策略等的改善.  相似文献   
4.
Loss of natural forests by forest clearcutting has been identified as a critical conservation challenge worldwide. This study addressed forest fragmentation and loss in the context of the establishment of a functional green infrastructure as a spatiotemporally connected landscape-scale network of habitats enhancing biodiversity, favorable conservation status, and ecosystem services. Through retrospective analysis of satellite images, we assessed a 50- to 60-year spatiotemporal clearcutting impact trajectory on natural and near-natural boreal forests across a sizable and representative region from the Gulf of Bothnia to the Scandinavian Mountain Range in northern Fennoscandia. This period broadly covers the whole forest clearcutting period; thus, our approach and results can be applied to comprehensive impact assessment of industrial forest management. The entire study region covers close to 46,000 km2 of forest-dominated landscape in a late phase of transition from a natural or near-natural to a land-use modified state. We found a substantial loss of intact forest, in particular of large, contiguous areas, a spatial polarization of remaining forest on regional scale where the inland has been more severely affected than the mountain and coastal zones, and a pronounced impact on interior forest core areas. Salient results were a decrease in area of the largest intact forest patch from 225,853 to 68,714 ha in the mountain zone and from 257,715 to 38,668 ha in the foothills zone, a decrease from 75% to 38% intact forest in the inland zones, a decrease in largest patch core area (assessed by considering 100-m patch edge disturbance) from 6114 to 351 ha in the coastal zone, and a geographic imbalance in protected forest with an evident predominance in the mountain zone. These results demonstrate profound disturbance of configuration of the natural forest landscape and disrupted connectivity, which challenges the establishment of functional green infrastructure. Our approach supports the identification of forests for expanded protection and conservation-oriented forest landscape restoration.  相似文献   
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The occurrence of antihistamines in sewage waters and in recipient rivers   总被引:2,自引:1,他引:1  
Background, aim and scope  Each year, large quantities of pharmaceuticals are consumed worldwide for the treatment and prevention of human and animal diseases. Although the drugs and the metabolites observed in the wastewaters and in the environment are present at concentrations several orders of magnitude lower than the concentrations required to exert their effects in humans or animals, their long-term impact on the environment is commonly not known. In this study, the occurrence of six antihistamines, which are used for the relief of allergic reactions such as hay fever, was determined in sewage treatment plants wastewaters and in recipient river waters. Materials and methods  The occurrence of the antihistamines cetirizine, acrivastine, fexofenadine, loratadine, desloratadine and ebastine in sewage treatment plants wastewaters and in recipient river waters was studied. The analytical procedure consisted of solid-phase extraction of the water samples followed by liquid chromatography separation and detection by a triple-quadrupole mass spectrometer in the multiple reaction mode. Results  Cetirizine, acrivastine and fexofenadine were detected in both influent and effluent wastewater samples at concentration levels ranging from about 80 to 220 ng/L, while loratadine, desloratadine and ebastine could not be detected in any samples. During sewage treatment, the concentration of the antihistamines dropped by an average of 16–36%. Furthermore, elevated concentrations of antihistamines were observed in samples collected during the season of most intensive plant pollen production, i.e. in May. In the river water samples, the relative pattern of occurrence of cetirizine, acrivastine and fexofenadine was similar to that in the wastewater samples; although the concentration of the compounds was substantially lower (4–11 ng/L). The highest concentrations of the studied drugs were observed near the discharging point of the sewage treatment plant. Discussion  The highest concentrations of antihistamines in STP wastewaters correlate with the outbreak of allergic reaction caused by high amounts of plant pollens in the air. The analysis results of the river water samples show that the antihistamines are carried far away from the effluent discharge points. They may account for a part of the mix of pharmaceuticals and of pharmaceutical metabolites that occur downstream of STPs. Conclusions  Antihistamines are poorly degraded/eliminated under the biological treatment processes applied in the wastewater treatment plants and, consequently, they are continuously being discharged along with other drugs to the aquatic environment. Recommendations and perspectives  As a huge quantity and variety of drugs and their metabolites are continuously discharged to rivers and the sea, the compounds should be considered as contaminants that may possess risks to the aquatic ecosystem. Further studies are urgently needed on the environmental fate of the antihistamines and other pharmaceuticals in the aquatic environment. These studies should be concerned with the stability of the compounds, their transformation reactions and the identity of the transformation products, the distribution of drugs and their uptake and effects in organisms. On the basis of these studies, the possible environmental hazards of pharmaceuticals may be assessed.  相似文献   
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9.
Maternal transfer of brominated flame retardants in zebrafish (Danio rerio)   总被引:1,自引:0,他引:1  
In many species reproduction and embryonic development have been shown to be sensitive to environmental contaminants. Understanding embryonic exposure to environmental contaminants is thus highly important. In this study concentrations of brominated flame retardants (BFRs) were measured in zebrafish eggs after parental exposure for 42 days via the diet. Zebrafish were exposed to two doses of eleven structurally-diverse BFRs. Eight BFRs were detected in the female zebrafish and maternal transfer to eggs was evident for all eight compounds. The highest concentrations in eggs were observed for hexabromocyclododecane (HBCD) and 2,4,4'-tribromodiphenyl ether (BDE 28), followed by 2,2',3,4,4',5',6-heptabromodiphenyl ether (BDE 183) and tetrabromobisphenol A 2,3-dibromopropyl ether (TBBPA DBPE). Five potential BFR metabolites were tentatively identified in female fish and maternal transfer was observed also for these compounds. The lipid adjusted concentrations in eggs were significantly higher than the concentrations in female fish for several of the BFRs. Further, the results showed a generally higher transfer in the lower exposure level and also indicated a dependency on the physico-chemical properties of the compounds.  相似文献   
10.

The aim of this study is to assess the impact of two forms of short-term knowledge communication—lectures and group deliberations—on public managers’ policy beliefs regarding genetic biodiversity in the Baltic Sea. Genetic biodiversity is a key component of biological variation, but despite scientific knowledge and far-reaching political goals, genetic biodiversity remains neglected in marine management. Previous research highlights lack of knowledge among managers as one explanation to the implementation deficit. This multidisciplinary study builds on the identified need for an improved knowledge transfer between science and ongoing management. A basic knowledge package on genetic biodiversity in the Baltic Sea was presented as either a lecture or a deliberative group discussion to two separate samples of public managers who are involved in Baltic Sea and other biodiversity management at the regional level in Sweden. The empirical findings show that the communicated information has an impact on the public managers’ beliefs on genetic biodiversity of the Baltic Sea. Lectures seem more efficient to transfer knowledge on this theme. Those who received information through a lecture strengthen their confidence in area protection as a management tool to conserve genetic diversity. They were also more convinced of the obligation of authorities at national and regional level to take on larger responsibility for genetic conservation than those managers who participated in a deliberative discussion.

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