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441.
The focus of the paper is the ethical issues associated with the practice of dissecting animals in lower level college biology classes. Several arguments against dissection are explored. Furthermore, the issue is examined from the point of view of the instructor's academic freedom and the point of view of a student's moral autonomy. It is argued that even though the arguments against dissection fail, it is very important to respect the moral autonomy of students who oppose the practice. Often this can be accomplished in a manner that is consistent with academic freedom and good science education.  相似文献   
442.
This paper assesses the financing challenges which have to be met by developing countries if water resources are to be managed efficiently, if the quality of the aquatic environment is to be improved and if water related services are to be delivered in a responsive, efficient and equitable way. This paper takes the view that attaching 'price tags' to water supply and sanitation, as was tentatively done in Agenda 21, is a misguided approach and that what is needed is articulation of clear principles which should underpin the financing of water supply and sanitation investments. To illustrate the approach the paper focuses heavily on experiences from World Bank water supply, sanitation and urban development projects over the past 30 years. The challenge is to develop appropriate institutional and financial arrangements. The essence of such arrangements is that they ensure that societies mobilize appropriate levels of resources for providing water related environmental services and that these resources are used in the most efficient and effective way possible .  相似文献   
443.
Forestry and energy policies in Malawi place the blame for the country's high rate of deforestation on the demand for woodfuel. The government has been involved in a range of questionable supply-side initiatives, as well as in a number of interventions in woodfuel markets, with the objective of slowing rates of deforestation. It seeks to encourage farmers to grow woodfuel to meet market demands, and has provided subsidies to do so. The Forest Department has kept prices for firewood from its plantations low, both in order to discourage the market for wood from free resources and because of concerns about the impact of high producer prices on the urban poor. In doing so, the government is less able to rely on the market to provide producers with the incentive to plant trees to meet market demands. In any event, the market accounts for a relatively small proportion of total woodfuel demand. Policies do not distinguish between rural household demands and the specific market demands which are having the greatest impact on deforestation: woodfuel for urban markets, for tobacco curing, and for small industries. These, coupled with the expansion of the estate sector, have had afar greater impact on woodland clearance than rural, subsistence woodfuel demands. Rural household energy demands need to be addressed from a much broader perspective which considers the household's larger needs for tree based products or outputs: income, food, fibre, fodder, soil fertility, as well as for fuel .  相似文献   
444.
Material efficiency improvement saves energy and reduces the consumption of primary resources and reduces the volume of waste. In this article an approach for analysing the potential for material efficiency improvement is proposed and discussed. In this approach the product functions performed by the materials and various improvement measures are taken into account. The potential for material saving and associated energy saving is assessed and evaluated economically. In this paper the approach is tested in an analysis of the potential for material efficiency improvement with respect to plastic packaging in the Netherlands. The technical reduction potential is found to be 34 ± 7% (157 ± 30 ktonne virgin plastics). Realization of this potential would improve the energy efficiency of the lifecycle of plastic packaging by 31% (10 PJ in 1988). From our study we conclude that our approach can indeed be used to investigate the potential for material efficiency improvement. However, a reliable technical and particularly an economical assessment of reduction measures cannot be made until more detailed data become available.  相似文献   
445.
Impact scoping is the process of identifying important issues of a proposal and focusing the environmental impact assessment (EIA) on the high-priority issues. Although impact scoping in one form or another has been inherent to EIA for some time, documentation of its development and discussion of refinements to impact scoping processes have not been forthcoming. This article traces the development of impact scoping through time and highlights the need for such processes in EIA. A focused environmental assessment (FEA) approach to impact scoping that is suitable for implementation in an EIA is presented here and advantages of its use are delineated. FEA is a three-staged process that encourages impact scoping through progressive steps including impact identification, assessment and management planning. FEA combines a suite of EIA methods including: issues matrices, impact hypotheses, valued ecosystem components, and stakeholder participation sessions to effectively integrate impact scoping with EIA.  相似文献   
446.
A study was carried out to evaluate the interaction effect of sewage and duration of consumption on the production traits of pullets. Intake of the test waters was a function of their degree of acceptability when intake was voluntary at periods of low ambient temperatures. The intiation of egg production in all groups began after five weeks of treatment and differences in egg weight of the groups was slight and not significant (P > 0.05). The effect of the sewage waters on growth was pronounced only when the birds were in lay and the alum-treated sewage promoted higher body weight gain. The feed conversion ratio and the feed intake were not affected significantly (P > 0.05) by the interaction, and both had the same trend. The eggshell thickness was sensitive to changes in ambient temperature.  相似文献   
447.
HermanMiller, Inc. is recognized as one of the most environmentally responsive companies in the United States. It recently received the coveted President'S Environment and Conservation Challenge Award. Top management credits the company'S forty-year-old participatory management tradition as a key to its environmental success. This article shows how these “bottom-up” initiatives have created impressive “bottom-line” results.  相似文献   
448.
ABSTRACT: Thirty-five lakes in southern Labrador sampled in 1981 were resampled in 1989 and water chemistry values were compared between visits. Results showed higher pH, specific conductance, acid neutralization capacity, color, and base cations values in 1989, though sulfate, the ion most likely to reflect acid precipitation impacts, did not vary. The major ion changes measured were probably due to natural hydrological variations and not to changes in acid inputs. Results from the 1989 data showed a slight, but significant, decrease in water sulfate concentration trend from western to eastern Labrador, though most values, even in the western portion of the study area, fell close to the values considered “background” by Brakke et at. (1989). Base cation concentrations exceeded those which could be predicted from weathering by carbonic and bicarbonic acid. Assuming that little weathering is generated by acid precipitation in this region, the excess cations measured are probably a result of bedrock dissolution from organic acids generated by plant decomposition. Calculations showed that organic acid effect could be responsible for 9 to 52 percent of total weathering in the study basins.  相似文献   
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