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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   
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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   
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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 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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Rune Elvik 《Safety Science》2010,48(9):1189-1196
This paper discusses how incentives for setting efficient priorities in road safety policy can be strengthened. Efficient priorities are characterised by the use of cost-effective road safety measures. Cost-effective road safety measures can be identified by means of cost-benefit analyses. Studies of the actual priorities in road safety policy, in particular in the Scandinavian countries, suggest that these priorities are inefficient, i.e. characterised by the non-use or sub-optimal use of cost-effective road safety measures as well as an extensive use of ineffective road safety measures. This occurs despite the fact that road safety policy analyses have included extensive cost-benefit analyses of road safety measures. It would thus appear that cost-benefit analyses do not necessarily generate a sufficient incentive to implement cost-effective road safety measures. Possible reasons for this are discussed in the paper. It is argued that a large part of the monetary benefits of road safety measures, as estimated in cost-benefit analyses, are not subject to market transactions, and do therefore not manifest themselves in the form of increased income or higher profits. While cost-benefit analyses are indispensable as a means of identifying cost-effective road safety measures, their influence on actual road safety policy needs to be strengthened by providing additional incentives for the use of cost-effective road safety measures. It is suggested that a system of road pricing could generate such incentives. A brief sketch of a hypothetical system of road pricing is given and some problems associated with the implementation of this system are discussed.  相似文献   
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In the development of oxy-fuel combustion, reburning of nitrogen oxides, recycled with the flue gases, has been investigated for primary NOx control. Reduction of between 50 and 80% of the recycled nitrogen oxides has been measured. The present work evaluates the performance of gaseous and solid fuels as agents for reduction of nitrogen oxides by comparing experimental and modelling work performed at Chalmers University of Technology with different fuels. It is shown that the reduction is similar during propane and lignite firing, but that the lignite has slightly higher reduction efficiency. Differences in combustion temperature and heterogeneous effects are possible explanations.  相似文献   
10.
We explored the effect of varying pseudo-absence data in species distribution modelling using empirical data for four real species and simulated data for two imaginary species. In all analyses we used a fixed study area, a fixed set of environmental predictors and a fixed set of presence observations. Next, we added pseudo-absence data generated by different sampling designs and in different numbers to assess their relative importance for the output from the species distribution model. The sampling design strongly influenced the predictive performance of the models while the number of pseudo-absences had minimal effect on the predictive performance. We attribute much of these results to the relationship between the environmental range of the pseudo-absences (i.e. the extent of the environmental space being considered) and the environmental range of the presence observations (i.e. under which environmental conditions the species occurs). The number of generated pseudo-absences had a direct effect on the predicted probability, which translated to different distribution areas. Pseudo-absence observations that fell within grid cells with presence observations were purposely included in our analyses. We discourage the practice of excluding certain pseudo-absence data because it involves arbitrary assumptions about what are (un)suitable environments for the species being modelled.  相似文献   
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