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221.
Some western Norwegian fjords host extraordinarily abundant and persistent populations of the mesopelagic, coronate scyphomedusa, Periphylla periphylla. In these environments, from late autumn to spring, the medusae undertake regular diel vertical migrations into surface waters. From unique observations obtained with a remotely operated vehicle (ROV), including observations made without artificial light, we observed that 90% of the medusae swam with their tentacles in aboral position. Stomach content analyses of surface-collected specimens revealed that the medusae ate mainly calanoid copepods, but ostracods and large euphausiids were also prominent components of their diets. The clearance rate potential of P. periphylla, assessed from in situ observations and stomach contents, was comparable to that of similar-sized, epipelagic gelatinous species. Our findings suggest that P. periphylla behave as active predators in surface waters.  相似文献   
222.
Safety measures and related costs and benefits have been widely discussed and analysed in academic circles and by the authorities and industrial sectors. The study reported in this paper addresses these aspects from a cognitive based perspective. Risk management is about dealing with the conflict between production and safety. Enterprises which spend too much on safety will meet bankruptcy, and those not concerned with safety measures will meet with severe accidents and related damage. Inspired by James Reason’s theoretical framework, managers (n = 106) of commercial transport enterprises were asked about their attitudes towards safety management, what factors have contributed and their belief that further effort and investments in health, environment and safety (HES) measures will pay off. One half of the managers perceive HES work as too expensive and approximately one quarter assess mandatory HES work as compromising their competitiveness. One third of the managers do not find further safety measures than those already implemented necessary or remunerative. They claim that there are no other alternative ways of doing their activities and that there are no technical measures available that could meet outstanding safety challenges. Managers do acknowledge HES work as important for the reputation of the enterprise. The factor analysis gave five HES attitude factors: (I) concerned with formalities, (II) HES work improves health, environment and safety, (III) HES work is ineffective, (IV) HES regulation is appropriate, and (V) HES work can be improved.  相似文献   
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224.
Emissions from a small residential wood stove and a newly developed residential stove burning charcoal have been characterized by chemical analysis and mutagenicity testing (Ames Salmonella test). For wood burning the samples were taken under normal and starved air conditions burning birch and spruce separately. The burning conditions in the stove seemed to influence the emissions to a larger extent than the type of wood.The emissions of aldehydes, benzene and polycyclic aromatic hydrocarbons from the charcoal-burning stove are lower by a factor of 25–1000 as compared to the wood stove. The mutagenicity of the emissions showed a similar trend.  相似文献   
225.
Summary In 1986, the Danish Environmental Protection Agency established a new regulatory system aimed at small-scale polluting activities. Contrary to the dominant regulatory system based on individual standards for each polluting activity, the new regulatory system established uniform and fixed environmental standards for all activities within a trade. The fixed standards concern location, design and daily operation. Thus far, the new regulatory system has been implemented in the trades of fur farms and auto-repair shops.This study shows that fixed environmental standards reduce the total administrative costs, intensify local monitoring and enforcement of the standards, and improve the environmental state. It is proposed that the following criteria should be considered if the regulatory system is to be implemented in other trades. The trade should consist of many units and be characterised by a moderate pace of technological development, it should posses well-defined and well-known environmental problems, and have a cooperative trade association. In Denmark several trades have been identified as obvious objects for future regulation by fixed environmental standards.Bente Kjærgård is a Research Associate in the Department of Environment, Technology and Social Studies at Roskilde University. Correspondence should be addressed to this author. The other authors are Associate Professors in the same Department. Each author possesses a research degree as follows: Per Homann Jespersen in Chemical Engineering, Henning Schroll in Biology, Jesper Holm in Technological Planning, and Bente Kjærgård in Environmental Planning.  相似文献   
226.
In Spring 2015, a series of earthquakes and aftershocks struck Nepal. The earthquakes caused significant changes in labor and land availability, cash income needs, and land quality. We examine how these post-earthquake impacts converged with ongoing agricultural shifts. Earthquake-related socio-economic and landscape changes specifically motivate the adoption of cardamom, Amomum subulatum, a high-value ecologically beneficial, and low labor commercial crop. We investigate reasons for the increased interest in cardamom post-earthquake, and challenges associated with it. We find that adopting cardamom serves as an important post-disaster adaptation. However, more broadly, unevenly distributed interventions coupled with the high capital costs of agricultural transition exacerbate social differentiation in communities after the disaster. Adoption is often limited to economically better off smallholder farmers. This paper extends previous research on disasters and smallholder farming by highlighting the specific potential of disasters to accelerate agricultural transitions and resulting inequality from the changes.  相似文献   
227.
In this paper, wood waste (RWW) recovered for heat production in Sweden was studied. Previous research has concluded that RWW contains elevated amounts of heavy metals, causing environmental problems during waste management. This study extends previous work on RWW by analysing which pollution sources cause this contamination. Using existing data on the metal contents in various materials, and the amounts of these materials in RWW, the share of the elevated amounts of metals in RWW that these materials explain was quantified. Six different materials occurring in RWW were studied and the results show that they explain from 70% to 100% of the amounts of arsenic, chromium, lead, copper and zinc in RWW. The most important materials contributing to contamination of RWW are surface-treated wood, industrial preservative-treated wood, plastic and galvanised fastening systems. These findings enable the development and evaluation of strategies aiming to decrease pollution and resource loss from handling RWW. It is argued that source separation and measures taken further downstream from the generation site, such as treatment, need to be combined to substantially decrease the amount of heavy metals in RWW.  相似文献   
228.
229.
In Sweden, use of industrial residues is still hindered by concern for their long-term properties. A three-year research project was therefore initiated aiming to (1) identify the crucial processes of ageing related to the usefulness of residues in roads; (2) investigate the consequences of these processes for technical and environmental properties of the residues, and (3) propose a method for accelerated ageing to predict the long-term properties. This paper gives an overview of the project methodology, a summary of the test results and references to papers where further details are given.The project, running through 2006-2008, compared naturally aged samples of two residues used as sub-bases in existing asphalt paved roads with samples of fresh residues from producers’ piles. Steel slag of electric arc furnace (EAF) type and municipal solid waste incinerator (MSWI) bottom ash were chosen. The samples were thoroughly characterised in order to identify which ageing processes had been crucial.The results showed that:
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Bottom ash from the pavement edge was more aged than bottom ash from the road centre. However, no difference in pH was found, instead the differences were caused by differences in water exposure.
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Steel slag from the pavement edge showed traces of carbonation and leaching processes, whereas slag from the road centre was identical to fresh slag.
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Water exposure to the subbase materials after ten years in an asphalt paved road was calculated to less than 0.1-0.5 litres per kg.
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Ageing reactions in steel slag and MSWI bottom ash, ready for use, were too small to be verified by laboratory measurement of deformation properties under loaded conditions.
An accelerated ageing test for steel slag was set up to achieve the carbonation (decrease in pH) and leaching that was observed in the pavement edge material.An accelerated ageing test for bottom ash was set up to achieve the pozzolan reactions that were observed in SEM analyses of in situ specimens.It is recommended to use uncrushed particles when properties of aged material are studied, in order to preserve the original particle surfaces.  相似文献   
230.
Lichens are a bottleneck resource for circumpolar populations of reindeer, and as such, for reindeer husbandry as an indigenous Sami land-use tradition in northern Sweden. This study uses ground lichen data and forest information collected within the Swedish National Forest Inventory since 1953, on the scale of northern Sweden. We found a 71 % decline in the area of lichen-abundant forests over the last 60 years. A decline was observed in all regions and age classes and especially coincided with a decrease of >60 year old, open pine forests, which was the primary explanatory factor in our model. The effects of reindeer numbers were inconclusive in explaining the decrease in lichen-abundant forest. The role that forestry has played in causing this decline can be debated, but forestry can have a significant role in reversing the trend and improving ground lichen conditions.

Electronic supplementary material

The online version of this article (doi:10.1007/s13280-015-0759-0) contains supplementary material, which is available to authorized users.  相似文献   
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