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Regional Environmental Change - The rapid environmental changes currently underway in many dry regions of the world, and the deep uncertainty about their consequences, underscore a critical...  相似文献   
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The European Operational Smog (EUROS) integrated air quality modelling system has been extended to model fine particulate matter (PM). From an extended literature study, the Caltech Atmospheric Chemistry Mechanism and the Model of Aerosol Dynamics, Reaction, Ionisation and Dissolution were selected and recently coupled to EUROS. Currently, modelling of mass and chemical composition of aerosols in two size fractions (PM2.5 and PM10–2.5) is possible. The chemical composition is expressed in terms of seven components: ammonium, nitrate, sulphate, elementary carbon, primary inorganic compounds, primary organic compounds and secondary organic compounds. Calculated PM10 concentrations and chemical composition are presented for two summer months of the year 2003 (1 July to 31 August).  相似文献   
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Our understanding of natural ecosystems can be measured by our ability to predict their responses to external disturbances. Predictions made during environmental impact assessment (EIA) for major development projects are hypotheses about such responses, which can be tested with data collected in environmental monitoring programmes. The systematic comparison of predicted and actual impacts has been termed environmental impact audit. Ecosystem disturbances associated with major resource developments, though of lesser magnitude than those associated with natural cataclysms, are generally of far greater magnitude than those which can be applied experimentally. Environmental audit can hence provide critical tests of theory in a number of natural sciences. It is also needed to improve the scientific content of EIA. Audits of 4 and 29 EISs respectively have been carried out previously in the UK and USA, but this is the first national scale audit for any country. It is also the first attempt to select, from the many vague statements in EISs, only those predictions that are scientifically testable, and to determine and analyse their quantitative accuracies. Its principal results are as follows. The average accuracy of quantified, critical, testable predictions in environmental impact statements in Australia to date is 44%±5% s.e. Predictions where actual impacts proved more than expected were on average significantly (p<0.05) less accurate (33%±9%) than those where they proved as or less severe (53%±6%).  相似文献   
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本文使用由不同的全球模拟所产生的区域性耦合海洋-大气模型,通过数值模型试验探讨了波罗的海气候未来可能的物理状况.将一些情景以及近来的一些气候模拟情况作了比较,以估计气候变化.海面温度总体平均明显地增高2.9℃.平均年平均增温的水平模式主要可由冰盖的减少解释.由大气向波罗的海的热输送表现出季节性变化周期秋季热损失减少,春季热吸收增加,夏季热吸收减少.年际间海面温度的变化一般是在增加.这与北部一些中平滑的频率分布有关.全部热收支表示出海面太阳辐射在增加,而太阳辐射增加由热通量其他组成成分的变化所平衡.  相似文献   
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Call centre workplaces are in many ways a challenge to occupational health and safety. The occupation itself can be described as an IT information technology-supported, communication-intensive form of work with often unusual working hours and a high rate of part-time employment. Data on the employee turnover as well as absenteeism related to occupational disability is quite contradictory. Occupational safety and its proponents still have to find new ways into the corporate structures and cultures of this relatively new and rapidly growing branch of industry. In a 2-year research and development project, using a holistic approach and under consideration of all the relevant disciplines, call centre workplaces were studied, and organisational measures were developed and field tested by putting them into practice. Practical help was developed for a sustainable strategy for successful and healthy work in call centres.  相似文献   
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Bio-economic farm models are tools to evaluate ex-post or to assess ex-ante the impact of policy and technology change on agriculture, economics and environment. Recently, various BEFMs have been developed, often for one purpose or location, but hardly any of these models are re-used later for other purposes or locations. The Farm System Simulator (FSSIM) provides a generic framework enabling the application of BEFMs under various situations and for different purposes (generating supply response functions and detailed regional or farm type assessments). FSSIM is set up as a component-based framework with components representing farmer objectives, risk, calibration, policies, current activities, alternative activities and different types of activities (e.g., annual and perennial cropping and livestock). The generic nature of FSSIM is evaluated using five criteria by examining its applications. FSSIM has been applied for different climate zones and soil types (criterion 1) and to a range of different farm types (criterion 2) with different specializations, intensities and sizes. In most applications FSSIM has been used to assess the effects of policy changes and in two applications to assess the impact of technological innovations (criterion 3). In the various applications, different data sources, level of detail (e.g., criterion 4) and model configurations have been used. FSSIM has been linked to an economic and several biophysical models (criterion 5). The model is available for applications to other conditions and research issues, and it is open to be further tested and to be extended with new components, indicators or linkages to other models.  相似文献   
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