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351.
The use of passive sampler systems is reviewed and discussed. These devices are able to determine both spatial and temporal differences in canopy exposure, as is demonstrated by their use in extensive monitoring of air-pollution exposure in forest health plots. Categorising forest health monitoring plots according to air-pollution exposure permits cause-effect analysis of certain forest health responses. In addition, passive sampling may identify areas affected by interaction between different gaseous pollutants. Passive samplers at the stand level can be used to resolve vertical profiles of ozone within the stand, and edge effects, which are important in exposure of understorey and ground flora. Recent case studies using passive samplers to determine forest exposure to gaseous pollutants indicate a potential for the development of spatial models on regional-, landscape-, and stand-level scales and the verification of atmospheric transport models.  相似文献   
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This analysis presents the results of a life cycle assessment (LCA) carried out on six alternative options for the recycling of water at a Danish industrial laundry for workwear. The study focuses on the handling and disposal of the wet residues generated when wastewater is treated for recycling, and in accounting for long-term potential toxicity impacts. The analysed options are a combination of two water-upgrading technologies: biofilter and ultrafiltration, and three residue disposal alternatives: biogas followed by incineration of sludge at local wastewater treatment plant, thermal vitrification treatment for production of vitrified sand, and mineralization in a sludge bed. It is concluded from the results that with the current Danish environmental policy priorities, the environmental impacts of highest priority are the toxicity effects derived from the presence of heavy metals in the residues. Heavy metals originate from the dirt in the workwear that is washed in the laundry. It is further concluded that the studied water treatment technologies satisfy both the need of clean water for recycling and simultaneously help controlling a safe disposal of pollutants by concentration of the residues. The results of the study also confirm the potential of LCA as a decision-support tool for assisting water recycling initiatives and for residue handling management. The handling of residues has been identified as a stage of the water recycling strategy that bears important environmental impacts. This holistic perspective provided by LCA can be used as input for the definition of environmental management strategies at an industrial laundry, and the prioritization of investments to the environmental profile of laundry processes. In this case-study, the results of the LCA are made operational by, for example, selecting the water treatment technology which is associated wih a safe disposal of the wet residue. It is important to bear in mind that such prioritization depends on national boundary conditions. In the case study analysed, the boundary conditions steer the weighing of the environmental impacts, following the current Danish environmental policy priorities.  相似文献   
355.
A behavior (work) sampling approach was used to both develop and evaluate the effectiveness of an occupational safety training program for industrial lift truck operators. Two studies, each using different experimental designs and performed at two separate warehouses, were conducted, resulting in a total of 96 operators trained. Observations through several months of training program assessment indicated that: (a) occupational safety training, emphasizing modification of operationally defined unsafe work practices derived from task/hazard analysis, can be demonstrated to be effective and to endure beyond cessation of performance feedback; (b) the basis for endurance appears to be continued practice in the modified safe work procedures, coupled with a redefinition of group norms sustained through informal influences such as peer modeling of desired behaviors and continued management support of the program; and (c) a behavior sampling procedure, specifying performancebased criteria, can be used effectively in both the development and evaluation of an occupational-safety training program.  相似文献   
356.
The paper traces the author's background as a British geographer and the intellectual climate at Clark University in 1968 which led him out of urban social geography into the uncharted domain of children's knowledge of the geographic environment. Following the integration of theory and research on the development of spatial cognition in children came the need to investigate child development in relation to the physical landscape more comprehensively in a Ph.D. dissertation. Subsequent work, built entirely from this early base, continues to investigate children's use, knowledge and experience of physical environment in a variety of settings. Applications of research are made in both the fields of environmental education and environmental planning and design.  相似文献   
357.
Fly-ash dumped on the sea bed causes a local impoverishment of the benthos. Experiments on ash in sea water have shown bacterial colonization to occur, at a slower rate than on natural silt, limited meiofaunal colonization after 18 months, selection by meroplanktonic larvae for the ash, though inhibition of development after settlement, and selection against ash by mobile benthic adults. the major inhibition to colonization is the lack of organic content in the ash.  相似文献   
358.
This study reports on Kenyan school children's ideas about wildlife parks in their country. A comparison is made between the responses of school children in primary school, before they receive any science education, and those of secondary school pupils at the end of the secondary cycle. The findings show little difference between the two groups of students in terms of their ideas about wildlife parks. This has serious implications for science and environmental education in Kenya. Parks are understood by these pupils in terms of real life issues, as derived from social consequences. The children's ideas are all based on the role that parks play in society, but the function of parks to support biodiversity conservation does not seem to be important to the students. While it is satisfying to note that the school children have a good understanding of parks in their social context, it is essential to address fully the scientific and ecological role of parks in order that biodiversity becomes more valued in our society.  相似文献   
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ABSTRACT: Brillouin's equation (H) for species diversity from information theory is to be preferred for the purposes of applied ecology over the equation of Shannon (H′) or the more commonly used approximate equation (H″). By its use, the difficult problem of delimiting the extent of the community being sampled in a stream survey can be avoided. Moreover, Brillouin's equation gives the exact diversity of the fully censused collection, whreas Shannon's diversity can only be approximated with a biased estimator. If we regard a sample as a message from the environment to the ecologist, Brillouin's equation is the proper one for computing its diversity. The product moment correlation coefficient between Brillouin's H for the total number of individuals from a group of samples and for randomly chosen subsets of 100 individuals from each sample was nearly as high as the correlation between H and H″ based on the total samples. This indicates that small sample sizes may give a useful diversity index. Replicated subsamples show that much smaller samples than are normally used can discriminate between communities from polluted and unpolluted environments. The use of smaller samples should reduce the cost of stream surveys.  相似文献   
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