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141.
Work characteristics such as time pressure and job control can be experienced as a challenge that is positively associated with performance‐related behaviors. Using experience‐sampling data from 149 employees, we examined the relationships between these work characteristics and creativity and proactive behavior on a daily level. Results from multilevel analyses indicate that time pressure and job control are perceived as challenging, and that challenge appraisal in turn is related to daily creativity and proactive behavior. Furthermore, cross‐level mediation analyses revealed that daily work characteristics act as the mechanism underlying the relationships between chronic work characteristics and challenge appraisal. This study supports the view of time pressure as a challenge‐related stressor that leads to favorable outcomes. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
142.
Empirical and theoretical studies have only recently begun to examine how females use complex multi-component displays when selecting mates. Superb fairy-wrens are well suited to the study of female choice because females have control over extra-group paternity and cuckold their mates at high rates, while males possess a variety of sexually selected traits. Available evidence suggests that females base their extra-group mate choice on the timing of male moult into breeding plumage or the onset of display. However, males continue to perform elaborate displays throughout the season, and direct most displays to females during their fertile period. We therefore conducted focal observations on fertile females to quantify the frequency of male display and used microsatellite genotyping to compare the role of display rate during the breeding season and the timing of male moult on female mate choice. We show that the addition of data on male display rate does not improve our ability to predict which males obtain extra-group paternity. The timing of male moult into breeding plumage remains the only predictor of male extra-group reproductive success. Nevertheless, we found that males displayed more to females that were unable to select extra-group mates on the basis of the timing of moult or the onset of display. This raises the possibility that there are circumstances when females use display rate to discriminate between potential extra-group sires. Overall this study supports the theoretical prediction that females are more likely to base their mate choice on reliable indicators of male quality such as fixed morphological traits and displays of endurance, in this case an early moult into breeding plumage and the performance of an elaborate display during the winter, than a flexible behavioural trait such as display rate during the breeding season. Received: 26 January 2000 / Revised: 1 August 2000 / Accepted: 26 August 2000  相似文献   
143.
There is an increasing need and interest in including indicators of landscape fragmentation in monitoring systems of sustainable landscape management. Landscape fragmentation due to transportation infrastructure and urban development threatens human and environmental well-being by noise and pollution from traffic, reducing the size and viability of wildlife populations, facilitating the spread of invasive species, and impairing the scenic and recreational qualities of the landscape. This paper provides the rationale, method, and data for including landscape fragmentation in monitoring systems, using as an example the Swiss Monitoring System of Sustainable Development (Monet). We defined and compared four levels of fragmentation analysis, or fragmentation geometries (FGs), each based on different fragmenting elements, e.g., only anthropogenic, or combinations of anthropogenic and natural elements. As each FG has specific strengths and weaknesses, the most appropriate choice of FG depends on the context and objectives of a study. We present data on the current degree of landscape fragmentation for the five ecoregions and 26 cantons in Switzerland for all four FGs. Our results show that the degree of landscape fragmentation as quantified by the effective mesh size method is strongly supported by the postulates and indicator selection criteria of Monet, and we identify the most suitable FG focusing on the land area below 2100 m (e.g., excluding lakes) and allowing for an equitable comparison of fragmentation degrees among regions that differ in area covered by lakes and high mountains. For a more detailed analysis of landscape fragmentation in the context of environmental impact assessments and strategic environmental assessments, a combination of all four FGs may provide a more informative tool than any single FG.  相似文献   
144.
Bioaccumulation of persistent organic pollutants (POPs) leads to high levels in human milk and high doses of POPs for nursing infants. This is currently not considered in chemical risk assessment. A coupled model for bioaccumulation of organic chemicals in breast-feeding mother and nursing infant was developed and tested for a series of organic compounds. The bioaccumulation factors (BAFs) in mother, breast milk and child were predicted to vary with log KOW and, for volatile compounds, with KAW and concentration in air. The concentrations of POPs in the infant body increase the first half year to about factor 3 above mother and decline thereafter to lower levels. The predicted results are close to empirical data and to an empirical regression. The new mother–child model is compact due to its easy structure and the analytical matrix solution. It could be added to existing exposure and risk assessment systems, such as EUSES.  相似文献   
145.
The potential for aeration of MSW landfills to accelerate completion   总被引:4,自引:0,他引:4  
Landfilling is a popular waste disposal method, but, as it is practised currently, it is fundamentally unsustainable. The low short-term financial costs belie the potential long-term environmental costs, and traditional landfill sites require long-term management in order to mitigate any possible environmental damage. Old landfill sites might require aftercare for decades or even centuries, and in some cases remediation may be necessary. Biological stabilisation of a landfill is the key issue; completion criteria provide a yardstick by which the success of any new technology may be measured. In order for a site to achieve completion it must pose no risk to human health or the environment, meaning that attenuation of any emissions from the site must occur within the local environment without causing harm. Remediation of old landfill sites by aerating the waste has been undertaken in Germany, the United States, Italy and The Netherlands, with considerable success. At a pilot scale, aeration has also been used in newly emplaced waste to accelerate stabilisation. This paper reviews the use of aerobic landfill worldwide, and assesses the ways in which the use of aerobic landfill techniques can decrease the risks associated with current landfill practices, making landfill a more sustainable waste disposal option. It focuses on assessing ways to utilise aeration to enhance stabilisation. The results demonstrated that aeration of old landfill sites may be an efficient and cost-effective method of remediation and allow the date of completion to be brought forward by decades. Similarly, aeration of newly emplaced waste can be effective in enhancing degradation, assisting with completion and reducing environmental risks. However, further research is required to establish what procedure for adding air to a landfill would be most suitable for the UK and to investigate new risks that may arise, such as the possible emission of non-methane organic compounds.  相似文献   
146.
Orthophosphate monoesters often constitute a significant fraction of total phosphorus in lake sediments. The knowledge on the specific composition and recalcitrance of these compounds is however limited. The main aim was therefore to identify and quantify specific orthophosphate monoesters in sediment from 15 Danish lakes by solution (31)P NMR spectroscopy. The four most quantitatively important orthophosphate monoesters were myo-inositol hexakisphosphate (myo-IP(6)), scyllo-inositol hexakisphosphate (scyllo-IP(6)) α-glycerophosphate (α-GP) and β-glycerophosphate (β-GP). The compounds were identified in 9, 4, 8 and in all 15 lakes, respectively. In total these four components made up 46-100% of the orthophosphate monoester pool. The glycerophosphates (GPs) are most likely degradation products of phospholipids, created as an artifact by the alkaline extraction procedure used for (31)P NMR spectroscopy, while the inositol hexakisphosphates (IPs) are naturally occurring compounds. There was a significant positive correlation between myo-IP(6) and total aluminium in the sediment and a negative correlation between myo-IP(6) and lake water pH, suggesting that myo-IP(6) is stabilized in the sediment by adsorption at slightly acidic or neutral conditions. In three lakes, the depth distribution of the orthophosphate monoesters was investigated. The content of scyllo-IP(6) and myo-IP(6) was constant with sediment depth in two of the lakes while the content of myo-IP(6) decreased with depth in one of the lakes. In all cases the IPs seem to be preserved with sediment depth to a higher extent than the orthophosphate diesters and especially the GPs suggesting that IPs can be a sink for phosphorus in the lake ecosystem or at least delay P-recycling for years.  相似文献   
147.
A site in mid-western Sweden contaminated with chlorinated solvents originating from a previous dry cleaning facility, was investigated using conventional groundwater analysis combined with compound-specific isotope data of carbon, microbial DNA analysis, and geoelectrical tomography techniques. We show the value of this multidisciplinary approach, as the different results supported each interpretation, and show where natural degradation occurs at the site. The zone where natural degradation occurred was identified in the transition between two geological units, where the change in hydraulic conductivity may have facilitated biofilm formation and microbial activity. This observation was confirmed by all methods and the examination of the impact of geological conditions on the biotransformation process was facilitated by the unique combination of the applied methods. There is thus significant benefit from deploying an extended array of methods for these investigations, with the potential to reduce costs involved in remediation of contaminated sediment and groundwater.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01418-5) contains supplementary material, which is available to authorized users.  相似文献   
148.
The Mekong River Basin is considered to be the second most species rich river basin in the world. The 795,000 km(2) catchment encompasses several ecoregions, incorporating biodiverse and productive wetland systems. Eighty percent of the rapidly expanding population of the Lower Mekong Basin (LMB), made up in part by Lao PDR, Thailand, Cambodia and Viet Nam, live in rural areas and are heavily reliant on wetland resources. As the populations of Cambodia and Lao PDR will double in the next 20 years, pressure on natural resources and particularly wetlands can only increase. For development planning, resource and conservation management to incorporate wetland issues, information on the distribution and character of Mekong wetlands is essential. The existing but outdated wetland maps were compiled from secondary landuse-landcover data, have limited coverage, poor thematic accuracy and no meta-data. Therefore the Mekong River Commission (MRC) undertook to produce new wetland coverage for the LMB. As resources, funding and regional capacity are limited, it was determined that the method applied should use existing facilities, be easily adaptable, and replicable locally. For the product to be useful it must be accepted by local governments and decision makers. The results must be of acceptable accuracy (>75%) and the methodology should be relatively understandable to non-experts. In the first stage of this exercise, field survey was conducted at five pilot sites covering a range of typical wetland habitats (MRC wetland classification) to supply data for a supervised classification of Landsat ETM images from the existing MRC archive. Images were analysed using ERDAS IMAGINE and applying Maximum Likelihood Classification. Field data were reserved to apply formal accuracy assessment to the final wetland habitat maps, with resulting accuracy ranging from 77 to 94%. The maps produced are now in use at a Provincial and National level in three countries for resource and conservation planning and management applications, including designation of a Ramsar wetland site of international importance.  相似文献   
149.
Insurance is widely acknowledged to be an important component of an organisation's disaster preparedness and resilience. Yet, little analysis exists of how well current commercial insurance policies and practices support organisational recovery in the wake of a major disaster. This exploratory qualitative research, supported by some quantitative survey data, evaluated the efficacy of commercial insurance following the sequence of earthquakes in Canterbury, New Zealand, in 2010 and 2011. The study found that, generally, the commercial insurance sector performed adequately, given the complexity of the events. However, there are a number of ways in which insurers could improve their operations to increase the efficacy of commercial insurance cover and to assist organisational recovery following a disaster. The most notable of these are: (i) better wording of policies; (ii) the availability of sector‐specific policies; (iii) the enhancement of claims assessment systems; and (iv) risk‐based policy pricing to incentivise risk reduction measures.  相似文献   
150.
Perfluoroalkyl and polyfluoroalkyl substances (PFASs) are found in aquatic systems, flora, and fauna worldwide. These potentially harmful compounds are also frequently detected in Sweden and have already resulted in severe problems for public drinking water supply, i.e., some wells had to be closed due to high PFAS concentrations both in raw water and produced drinking water. Knowledge on PFAS occurrence in Sweden is still quite low, although monitoring is currently ongoing. This work describes potential sources for PFASs to enter the drinking water supply in Sweden and compares different occurrences of PFASs in raw and drinking water in the country. Moreover, the monitoring history, the legal situation, and remediation actions taken are presented. Finally, future challenges and the way forward in Sweden are discussed.  相似文献   
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