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71.
Pradhan A  Seena S  Pascoal C  Cássio F 《Chemosphere》2012,89(9):1142-1150
Increased commercialisation of nanometal-based products augments the possibility of their deposition into aquatic ecosystems; this, in turn, may pose risks to aquatic biota and associated ecological functions. Freshwater invertebrate shredders mostly use microbially-colonized plant litter as food resource and play an important role in aquatic detritus food webs. We assessed lethal effects of nanoCuO on the shredder Allogamus ligonifer (Trichoptera, Limnephilidae) by determining the concentration that induced 50% of death (LC50), and sublethal effects of nanoCuO on the feeding behaviour and growth of the shredder by exposing the animals to: (i) stream water supplemented with nanoCuO and microbially-colonized leaves, and (ii) stream water (without nanoCuO) and microbially-colonized leaves pre-exposed to nanoCuO. Results from acute lethal tests showed that the 96 h LC50 of nanoCuO was very high (569 mg L−1). In the absence of nanoparticles, leaf consumption rate was 0.27 mg leaf DM mg−1 animal DM d−1 and the shredder growth rate was 56 μg animal DM mg−1 animal DM d−1. A significant inhibition in leaf consumption rate (up to 47%) and invertebrate growth rate (up to 46%) was observed when shredders were exposed to the higher tested sublethal concentration of nanoCuO (75 mg L−1) through either contaminated stream water or pre-contaminated food. The exposure to increased nanoCuO concentration via water or pre-contaminated food led to higher accumulation of copper in the larval body. Leached water-soluble ionic copper from the nanoCuO adsorbed or accumulated in the shredder (up to 10.2% of total Cu) seemed to influence the feeding behaviour and growth of the shredder.  相似文献   
72.
This study aimed to develop a psychometrically sound measure of the construct of love and deep caring for nature as an expression of people’s personal and explicitly emotional relationship with nature. Expert opinion and pre-pilot surveys were employed for refinement of the item pool, and a sample of 307 university students was used in a major pilot study aiming to further purify scale items. A field trial was conducted using a sample of 261 tourists at leisure with nature. The final 15-item Love and Care for Nature (LCN) scale is differentiated from established measures of similar constructs, and demonstrates high internal consistency and sound validity. This research extends the psychological frameworks of environmental altruism, and has also taken the philosophical concept of biophilia, as love for nature, into the operational realm by making it perceptible and measurable.  相似文献   
73.
This study incorporated identity constructs into the theory of planned behaviour (TPB) to investigate intentions to engage in environmental activism. First year students and participants of a students of sustainability conference (n=169) were administered a questionnaire survey that measured standard TPB constructs as well as environmental group membership and self-identity as an environmental activist. Consistent with predictions, environmental group membership and self-identity were positive predictors of intentions. Thus, greater involvement in environmental groups and a stronger sense of the self as an environmental activist were associated with stronger intentions to engage in environmental activism. There was also evidence that self-identity was a stronger predictor of intentions for participants with low rather than high environmental group membership. In accordance with the standard TPB model, participants with more positive attitudes toward and a greater sense of normative support for environmental activism also had greater intentions to engage in the behaviour. The implications for groups seeking to harness support for activities to protect the environment are discussed.  相似文献   
74.
Throwing products away before they fail or are broken is at the heart of consumer behaviour in developed economies such as the UK. Products are often discarded for reasons of fashion, or to keep up with technological advances, rather than because they have reached the end of their functional life. Such behaviours contribute to resource depletion, greenhouse gas emissions, and physical waste which needs to be managed. Extending the length of time that products are kept in use (whether by their original or subsequent owners) can contribute to greater resource efficiency, with significant potential to reduce greenhouse gas emissions. This research was undertaken to support the development of evidence-based policy in the UK on the role of longer product lifetimes in achieving sustainable consumption and waste prevention. Twelve qualitative discussion groups, involving 115 consumers, were carried out to explore consumer influences on product lifetimes including: which factors influence purchase decisions; the care of products in use; and disposal decisions. A new typology was developed to describe how products meet consumers’ various needs for ‘workhorses’, ‘investment’ and ‘up-to-date’ products; and how lifetime is an outcome of the ‘nature’ of a product (functional life) and its ‘nurture’ (lifetime in use) by consumers. The results demonstrate that consumers have come to expect constant and rapid up-dating of products. In particular, having the latest versions of products is strongly associated with personal identity and feelings of success in life. There is little evidence of concern about the environmental consequences of a ‘throwaway society’. The low cost of new products, which enables rapid updating for reasons of fashion, is a key barrier to encouraging consumers to keep products in use for longer. Some opportunities were identified however for certain ‘workhorse’ and ‘investment’ products that are valued more for their functionality than fashion.  相似文献   
75.
Summary. Recent studies have demonstrated that under weakly acidic conditions (pH 6.0), many prey fishes, including juvenile rainbow trout (Onchorhynchus mykiss), do not exhibit overt antipredator responses to conspecific chemical alarm cues. In laboratory trials, we investigated the potential effects of reduced pH on the ability of hatchery reared, predator naïve juvenile rainbow trout to acquire the recognition of a novel predator (yellow perch, Perca flavenscens). Initially, we exposed trout to the odour of a predatory yellow perch, buffered to pH 6.0 (weakly acidic) or pH 7.0 (neutral) paired with conspecific skin extracts (also buffered to pH 6.0 or 7.0) or a distilled water control. Juvenile trout exhibited significant increase in antipredator behaviour when exposed to neutral skin extract (pH 7.0). When retested 48 hours later to perch odour alone (pH 7.0), only trout initially conditioned with neutral skin extracts (pairs with either neutral or acidic perch odour) exhibited a learned recognition of perch odour as a predator risk. Those initially exposed to weakly acidic skin extract or the distilled water control did not show a learned response to predator odour. These results demonstrate that the ability to acquire the recognition of novel predators is impaired under weakly acidic conditions, as would occur in natural waterways affected by acidic precipitation.  相似文献   
76.
The successful management of atmospheric pollution is best achieved when the benefits of controls can be clearly demonstrated to those who the controls affect. There is a need to demonstrate to a population that change will benefit the social and biophysical aspects of that population’s environment as a whole. This paper suggests that policy-makers need to demonstrate clearly the advantages of a change in behaviour for the local environment while concurrently minimising the life-style costs of the people whose co-operation is needed to bring that change about. This requires an improved understanding of the activities affected and the message and media by which environmental benefits can be communicated in the light of that understanding.Using the example of tropospheric ozone, this paper argues that air-quality management requires close regional co-ordination which can facilitate the establishment and implementation of local policy options. The ability of the UK National Air Quality Strategy to achieve this in its present form is discussed and the existence of a strategic gap between the current approach to air-quality management and the major issues surrounding air quality considered.  相似文献   
77.
An analysis of the ethical impacts of the use of anAutomatic Milking System (AMS) is employed as a casestudy to illustrate the use of a form of bioethicalanalysis in technology assessment. The approach isbased on the Ethical Matrix, where `impacts' areassessed in terms of (lack of) respect for threeethical principles as applied to interest groups. Inthis case, only impacts on dairy cows are examined,and principally in terms of their behaviouralfreedom.In contrast to traditional milking systems, AMS, inprinciple, allow cows to present for milkingvoluntarily. So with AMS, it is claimed that dairymanagement relies on the autonomous interaction of thecow with her environment.One of the roles of bioethical analysis is to identifythe influence of rhetoric and symbolism in technologyassessment, e.g., with respect to the claimed`voluntariness' of cows' presentation. The AMS can beinstalled to allow cows three types of access, viz., i)free choice ii) rewarded access (RA) iii) obligatoryaccess (OA). Studies suggest the desire for milkremoval per se is not critical in the cow'sattendance at the AMS. Continued motivation to bemilked, required for the system to function,principally relies on RA and OA. Both RA and OA aresubject to numerous factors, such as: design of theAMS, location, etc. In turn, these can affect thecows' behavioural freedom and welfare.One of the aims of this approach is to illustrate theethical basis on which public policy is or can beformulated.  相似文献   
78.
Here, we study distribution of workload and its relationship to colony size among worker ants of Temnothorax albipennis, in the context of colony emigrations. We find that one major aspect of workload, number of items transported by each worker, was more evenly distributed in larger colonies. By contrast, in small colonies, a small number of individuals perform most of the work in this task (in one colony, a single ant transported 57% of all items moved in the emigration). Transporters in small colonies carried more items to the new nest per individual and achieved a higher overall efficiency in transport (more items moved per transporter and unit time). Our results suggest that small colonies may be extremely dependent on a few key individuals. In studying colony organisation and division of labour, the amount of work performed by each individual, not just task repertoire (which tasks are performed at all), should be taken into account.  相似文献   
79.
Each year, millions of tonnes of waste are generated worldwide, partially through the construction and demolition of buildings. Recycling the resulting waste could reduce the amount of materials that need to be manufactured. Accordingly, the present work has analysed the potential reuse of construction waste in concrete manufacturing by replacing the natural aggregate with recycled concrete coarse aggregate.However, incorporating alternative materials in concrete manufacturing may increase the pollutant potential of the product, presenting an environmental risk via ground water contamination.The present work has tested two types of concrete batches that were manufactured with different replacement percentages. The experimental procedure analyses not only the effect of the portion of recycled aggregate on the physical properties of concrete but also on the leaching behaviour as indicative of the contamination degree. Thus, parameters such as slump, density, porosity and absorption of hardened concrete, were studied. Leaching behaviour was evaluated based on the availability test performed to three aggregates (raw materials of the concrete batches) and on the diffusion test performed to all concrete.From an environmental point of view, the question of whether the cumulative amount of heavy metals that are released by diffusion reaches the availability threshold was answered. The analysis of concentration levels allowed the establishment of different groups of metals according to the observed behaviour, the analysis of the role of pH and the identification of the main release mechanisms. Finally, through a statistical analysis, physical parameters and diffusion data were interrelated. It allowed estimating the relevance of porosity, density and absorption of hardened concrete on diffusion release of the metals in study.  相似文献   
80.
Safety studies for production and use of hydrogen reveal the importance of accurate prediction of the overpressure effects generated by delayed explosions of accidental high pressure hydrogen releases. Analysis of previous experimental work demonstrates the lack of measurements of turbulent intensities and lengthscales in the flammable envelope as well as the scarceness of accurate experimental data for explosion overpressures and flame speeds. AIR LIQUIDE, AREVA STOCKAGE ENERGIE and INERIS join in a collaborative project to study un-ignited and ignited high pressure releases of hydrogen.The purpose of this work is to map hydrogen flammable envelopes in terms of concentration, velocity and turbulence, and to characterize the flame behaviour and the associated overpressure. These experimental results (dispersion and explosion) are also compared with blind FLACS modelling.  相似文献   
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