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341.
This study finds support for the situational approach to affect determination in a prospective, two-year longitudinal field study. Specifically, turnover was shown to predict changes in subsequent job measures of work satisfaction and mental health. Employees who changed jobs and occupations showed greater increases in both work satisfaction and mental health than employees who only changed jobs or employees who remained in their initial positions. Further research directions are introduced.  相似文献   
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343.
Laboratory experiments on ovigerous females of northern shrimp (Pandalus borealis) were used to assess the effects of temperature and food ration on female condition during incubation and examine how combined effects of temperature and female condition influenced egg survival, embryonic development, and larval characteristics. Ovigerous females were maintained at 2°C, 5°C, and 8°C and fed on a low (three times/week; 2–2.7% W/W) or high ration (five times/week at satiation). The increase in temperature accelerated the developmental time of the eggs but their survival at 8°C was reduced. Conversion efficiency of yolk reserves in developing embryos was significantly reduced at elevated temperatures and larvae hatching at 2°C and 5°C were significantly larger and heavier than those hatching at 8°C. The experimental design did not result in any effect of food ration on the energetic condition of females or on egg characteristics and their biochemical composition. However, lower energy reserves were observed for females held at 8°C.  相似文献   
344.
The South Pennines, an area of acid-sensitive geology at the centre of a major industrial region, have undergone perhaps the most severe historic exposure to sulphur and nitrogen deposition in the UK. This study addresses a lack of existing research on the region by presenting the findings of a survey of 62 surface waters sampled during a 1-week period in April 1998. Results indicate that acidification in the region is acute; 27 of the sampled surface waters had a negative acid neutralising capacity (ANC) and 28 had a pH below 5.0. Minimum recorded pH values were below 4.0. Non-marine sulphate levels were extremely high (median 222 microeq/1), and widespread high nitrate concentrations (median 41 microeq/1) suggest that soils in the region as a whole may be at an advanced stage of nitrogen saturation. A consistent relationship was identified between site acidity and the balance between the major weathering-derived cations, calcium and magnesium, and sulphate. This could in turn be linked to catchment soil type and land use, with the most acidic conditions occurring in peat-dominated catchments, where weathering is minimal and the influence of atmospheric deposition most pronounced. Percentage of peat in each catchment was the single best predictor of surface water acidity. Nitrate concentrations, although not a dominant control on acidity, varied significantly according to land use. Elevated concentrations were observed in catchments containing forestry, due to enhanced deposition inputs, and in catchments containing improved land, linked to fertiliser use. Ammonium concentrations, although low at most catchments, were a significant component of the inorganic nitrogen total in a number of surface waters draining waterlogged peat catchments.  相似文献   
345.
A novel technique for the rapid screening of polyaromatic hydrocarbons (PAHs) in atmospheric particulates is presented. Two-step laser desorption laser photoionisation time-of-flight mass spectrometry was used to assay for PAHs in cloud-water particulates collected near Peebles in southern Scotland. The particulates were examined in situ on their host filters removing the requirement for time-consuming sample extraction and separation. The mass spectra obtained from a single filter are shown. The principal components of these are assigned to PAH contaminants and phthalate contaminants. A distribution of PAHs was observed using 193 nm laser photoionisation. The mass spectrum obtained on using 248 nm laser photoionisation exhibits a different intensity distribution demonstrating an ionisation wavelength dependence. The utility of the technique for rapid screening of PAHs and other polyaromatic species is discussed.  相似文献   
346.
347.
This paper extends prior research on risk perceptions in the West to the Hong Kong Chinese context by studying the nature of the responses of 229 Hong Kong Chinese to an adapted environmental appraisal inventory (EAI-C), which consisted of three scales with one related to the self and the other two related to the local and global environments, respectively. Results lent support to a local–global dichotomy: hazards were appraised to be more threatening in the global than the local context. Responses to the three-scale adaptation were factor analysed and three subscales were extracted for each of the EAI scales. As with findings reported in a previous study with an Irish sample, the subscales could be considered to represent techno-human, everyday-life and natural hazards. Results also indicated that Hong Kong Chinese appraised environmental hazards as more threatening than did Western samples surveyed in prior studies. This was most striking when hazards were appraised in relation to the self. Similar findings have also been reported in recent studies with Japanese samples. It was suggested that the accentuated threat to self observed in the current study might stem from a heightened sensitivity to environmental hazards in the Chinese people, which is determined by self-construction processes specific to Asian cultures. Using the EAI as a measurement for hazard appraisal may provide insights to how people from different cultures construe the impact of environmental hazards in various contexts.  相似文献   
348.
Irrigated Agriculture and Wildlife Conservation: Conflict on a Global Scale   总被引:10,自引:0,他引:10  
/ The demand for water to support irrigated agriculture has led to the demise of wetlands and their associated wildlife for decades. This thirst for water is so pervasive that many wetlands considered to be hemispheric reserves for waterbirds have been heavily affected; for example, the California and Nevada wetlands in North America, the Macquarie Marshes in Australia, and the Aral Sea in central Asia. These and other major wetlands have lost most of their historic supplies of water and some have also experienced serious impacts from contaminated subsurface irrigation drainage. Now mere shadows of what they once were in terms of biodiversity and wildlife production, many of the so-called "wetlands of international importance" are no longer the key conservation strongholds they were in the past. The conflict between irrigated agriculture and wildlife conservation has reached a critical point on a global scale. Not only has local wildlife suffered, including the extinction of highly insular species, but a ripple effect has impacted migratory birds worldwide. Human societies reliant on wetlands for their livelihoods are also bearing the cost. Ironically, most of the degradation of these key wetlands occurred during a period of time when public environmental awareness and scientific assertion of the need for wildlife conservation was at an all-time high. However, designation of certain wetlands as "reserves for wildlife" by international review boards has not slowed their continued degradation. To reverse this trend, land and water managers and policy makers must assess the true economic costs of wetland loss and, depending on the outcome of the assessment, use the information as a basis for establishing legally enforceable water rights that protect wetlands from agricultural development.  相似文献   
349.
黑河下游额济纳河沿岸绿洲是阿拉善独特的三道生态屏障——额济纳河沿岸绿洲、横贯东西绵延800多公里梭梭林带、贺兰山天然次生林之一。三道生态屏障同时也是我国西北地区的一条重要生态防线。但由于气候旱化和对动植物资源的不合理开发利用等因素的共同作用,目前黑河下游额济纳河沿岸绿洲生态功能退化严重,生态防护功能受损。为改善黑河下游额济纳河沿岸绿洲的生态环境状况,恢复额济纳绿洲生态功能,需要尊重自然规律,遵循生态学原理,在可持续发展原则指导下合理开发、利用自然资源,加大环保监管力度,综合运用经济、工程、法制、宣传等规划管理措施和手段加强生态环境保护与建设,保护额济纳绿洲生态屏障。  相似文献   
350.
Executives are increasingly paying attention to the importance of supply chain management [Lambert DM, Cooper MC. Issues in supply chain management. Industrial Marketing Management 2000;29(1):65–83; Hagelaar GJLF, van der Vorst JGAJ. Environmental supply chain management: using life cycle assessment to structure supply chains. International Food and Agribusiness Management Review 2002;4:399–412]. The management of the supply chain can be a central aspect of a company's competitive advantage [Preuss L. Rhetoric and reality of corporate greening: a view from the supply chain management function. Business Strategy and the Environment 2005;14:123–139]. SCM also offers considerable opportunities to reduce a company's environmental impact. The supply chains of three small and medium enterprises (SMEs) operating in the Burnside Industrial Park in Nova Scotia, Canada were investigated to explore the opportunities to improve environmental performance of SMEs linked in supply chains. This study confirmed that time and, to a lesser degree, financial resources to address solid waste and energy issues are the greatest limiting factors. Small suppliers, and even to a certain degree medium-sized enterprises, have difficulties in allocating resources to initiatives that are not viewed as directly related to their core function, namely manufacturing the product or providing the service. This study clearly demonstrated that opportunities exist to reduce greenhouse gas emissions and solid waste. Although, the benefits that would be gained from the implementation of any of the individual actions in the supply chains explored in this study are individually small, the cumulative benefits that could be achieved among supply chains and within industrial parks are substantial, given the number of small- and medium-sized enterprises.  相似文献   
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