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Feeding ecology of Greenland halibut (Gr. halibut) (Reinhardtius hippoglossoides) and sandeel (Ammodytes sp.) larvae on the West Greenland shelf was studied during the main part of the productive season (May, June and July). Copepods were the main prey item for larval Gr. halibut and sandeel, constituting between 88 and 99% of the ingested prey biomass. For both species, absolute size of preferred prey increased during ontogeny. However, preferred copepod size in relation to larval length differed markedly. In Gr. halibut, the relative size of the prey declined during growth of the larvae, while it remained constant for sandeel at a level of 2.7% of larval length. This led to a reduction in prey niche overlap between the two species. The available prey copepod biomass differed distinctly across the shelf area. In May, the prey density of Gr. halibut was the highest in the off-shelf area in Davis Strait. In June and July, the prey-rich areas for both species were mainly located at the slopes of the banks and at the shelf break area. Gut fullness was higher in these areas than in neighbouring areas, suggesting that the larval food resource could be scarce. The feeding ecology of Gr. halibut and sandeel could explain why larval abundance indices of the two species have historically shown opposite responses to yearly environmental conditions and total zooplankton occurrence.  相似文献   
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Purpose. To study whether perceptual identification should be included as a measure to evaluate physiological stress. Methods. Physiological variables oxygen uptake (VO2), ventilation, heart rate, blood lactate concentration, rectal temperature (Trec) and mean skin temperature, and perceptual variables rate of perceived exertion, thermal sensation and time to exhaustion, were measured at submaximal and maximal intensities during graded exercise on a treadmill to exhaustion in 12 firefighters wearing protective clothing and extra mass at 40 and 10 °C. Physiological strain index (PhSI) and perceptual strain index (PeSI) were calculated. Results. Apart from Trec, all physiological and perceptual variables were higher at submaximal intensities of 40 °C. Time to exhaustion was 16% shorter and the corresponding VO2 was reduced by 7% in the heat. A high correlation (r?=?89) between PhSI and PeSI was found at both temperatures. PeSI scores were equal to PhSI at both ambient temperatures, except at the two highest intensities in the heat, where PeSI was higher. Conclusions. These findings support use of perceptual identification to evaluate physiological stress. However, at very high intensities under hot conditions the perceptual strain was estimated higher than the physiological strain. More precise indexes are needed to include perceptual measures in safety standard.  相似文献   
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This paper examines the vulnerability of households to disasters, using an asset vulnerability framework to represent livelihoods. Such frameworks are widely employed to analyse household poverty and focus on living conditions and well-being rather than money-metric measures of consumption and income. The conceptualisation of household vulnerability is a challenge in current studies on coping with disasters. The paper considers whether a capital assets framework is useful in identifying and assessing household vulnerability in the context of the Wenchuan earthquake in China in 2008. The framework has five categories of assets (financial, human, natural, physical, and social capital) and attempts to measure the resilience and vulnerability of households. When applied to a major disaster, asset-based methods face the problem of heterogeneity of the population, such as with regard to livelihood type or residence. Moreover, the effect of external interventions, such as the provision of relief assistance, must be taken into account.  相似文献   
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Community gardens (CGs) in university settings are faced with challenges associated with a transient and inexperienced population of student gardeners, but they also have the potential to have a lasting impact on the food behaviours of many young people. This paper undertakes a systematic critical review of literature about University Community Gardens for Sustainability (UCGS) in order to suggest directions of future research in the emerging field research about CGs within and outside of universities. The literature shows that UCGS have similar benefits to those identified in urban CG literature; but with greater emphasis on both the educational and environmental sustainability benefits, suggesting an under-used potential of CGs in these areas. We argue that a better understanding of the particular challenges and benefits of UCGS could improve outcomes of CGs in all settings. Therefore we recommend that future should explore: (1) participant transience in CGs, thereby helping sustainability projects with large volunteer bases learn to cope with challenges this poses in order to maximise the garden’s impacts; (2) whether/how participating in CGs can contribute to changes in attitudes/behaviours with regards to sustainability and be used as a tool for Education for Sustainability in and outside of university settings and (3) failed cases of CGs to genuinely understand factors that contribute to success. By addressing these areas we can improve our understanding of how community gardening can contribute to our communities, universities and environment, and can begin to make these potential contributions a reality.  相似文献   
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Entrance tunnel construction at the Äspö Hard Rock Laboratory opened a conductive vertical fracture zone at a depth of 70 m on March 13, 1991. Three weeks later a sharp dilution front corresponding to 80% shallow water inflow to the originally saline fracture zone arrived at the entrance tunnel depth. In spite of this large inflow of shallow water, the fracture zone has remained persistently anoxic over a subsequent period. Results from gas sampling and 14C dating of dissolved organic and inorganic carbon conclusively show that recent organic carbon is being transported into the fracture zone and oxidized to carbon dioxide. These results are important when considering possible changes of redox status in the deep groundwater environment during construction and operation of a repository for spent nuclear fuel. Opening this fracture zone to large-scale surface water inflow adds reducing capacity in the form of organic carbon. This implies that the soil cover may provide important protection against input of dissolved oxygen to fractures being drained during the open phase of the repository.  相似文献   
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The abundance of plastics in stomachs of northern fulmars from the North Sea is used in the OSPAR Ecological Quality Objective (EcoQO) for marine litter. The preliminary EcoQO defines acceptable ecological quality as the situation where no more than 10% of fulmars exceed a critical level of 0.1 g of plastic in the stomach. During 2003-2007, 95% of 1295 fulmars sampled in the North Sea had plastic in the stomach (on average 35 pieces weighing 0.31 g) and the critical level of 0.1 g of plastic was exceeded by 58% of birds, with regional variations ranging from 48 to 78%. Long term data for the Netherlands since the 1980s show a decrease of industrial, but an increase of user plastics, with shipping and fisheries as the main sources. The EcoQO is now also used as an indicator for Good Environmental Status in the European Marine Strategy Framework Directive.  相似文献   
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