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This assessment of the environmental protection regulatory system for the $2.2 billion iron and steel plant, oil refinery, and thermal generating station composing the core of the greenfield Nanticoke industrial complex is based upon: the use of governmental and industrial research in project management; technology and institutional arrangements for environmental protection; evidence of environmental changes to date; analysis of government and industrial approval files; and interviews with government, industry, and interest group representatives. Planning, regulation, and management have been reasonably efficient and effective to the beginning of the operational stage for all three major industries as of spring 1980. Of major future concern, however, is management of the cumulative and synergistic impacts of the industries and associated development on air quality as well as the lands, waters, and sensitive ecosystems of the nearby Lake Erie coast. Continuous monitoring, more comprehensive research, and better overall coordination of government, industrial, and public interests are required if Nanticoke benefits are to be achieved without undue cost to pre-project resource users within and outside the Haldimand-Norfolk region.  相似文献   
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Root length of naturally grown young beech trees (Fagus sylvatica L.) was investigated in 26 forest plots of differing base saturation and nitrogen deposition. The relative length of finest roots (<0.25 mm) was found to decrease in soils with low base saturation. A similar reduction of finest roots in plots with high nitrogen deposition was masked by the effect of base saturation. The formation of adventitious roots was enhanced in acidic soils. The analysis of 128 soil profiles for fine roots of all species present in stands of either Fagus sylvatica L., Picea abies [Karst.] L. or both showed a decreased rooting depth in soils with < or =20% base saturation and in hydromorphic soils. For base rich, well drained soils an average rooting depth of 108 cm was found. This decreased by 28 cm on acidic, well drained soils. The results suggest an effect of the current soil acidification in Switzerland and possibly also of nitrogen deposition on the fine root systems of forest trees.  相似文献   
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Researchers have claimed that routinization hinders creativity. However, empirical evidence for this assumption is sparse. In this study, we argue that routinization may be beneficial for creativity and related behavior due to available resources that can be used to develop new ideas while working. We examine the relationship between routinization and four work characteristics (job control, job complexity, time pressure, and supervisor support) on the one hand and a range of creative and proactive behaviors on the other hand in a randomly selected sample of 278 employees of a German high‐tech company. Regression analyses reveal that in addition to work characteristics, routinization is generally positively related to creative and proactive behaviors. Ways to enhance routinization and thereby creative and proactive behaviors are discussed. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
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ABSTRACT: This study focused on the Sandusky Watershed (SW) in Ohio, located within the Great Lakes Basin, with emphasis on two of its subwatersheds, namely Honey Creek (HC) and Rock Creek (RC). The goal was to assess the capabilities of the Soil and Water Assessment Tool (SWAT) to simulate suspended sediment (SS), phosphorus (P) and nitrogen (N) yield in the SW that contribute major sediment and nutrient loads into Lake Erie. The model was calibrated using water flow and water quality parameters for water years 1998 to 1999 and validated model simulations covering the period of water years 2000 to 2001 for monthly conditions. The validation of SS showed correlation coefficients of 0.29 (SW), 0.75 (HC) and 0.69 (RC). Correlation coefficients for P were 0.68 (SW), 0.78 (HC) and 0.37 (RC); for N02‐N 0.84 (HC) and 0.38 (RC); for N03‐N 0.27 (HC) and 0.76 (RC); for NH3‐N 0.57 (SW), 0.49 (HC), and 0.13 (RC). In addition, mean errors, root mean square errors, Nash‐Sutcliffe coefficients, and graphs were used to compare simulated to measured data. Simulation success was variable with poor and good simulations, but in most cases, simulated water quality values followed the trend of measured data except for extreme (or intense) rainfall/runoff events. Reviews of 17 applications indicated that the SWAT is suitable for long term continuous simulations but not for storm events. A spatially distributed modeling approach generated maps showing the spatial distribution of SS, P, and N for each simulation element across the Sandusky Watershed.  相似文献   
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African mixed crop–livestock systems are vulnerable to climate change and need to adapt in order to improve productivity and sustain people’s livelihoods. These smallholder systems are characterized by high greenhouse gas emission rates, but could play a role in their mitigation. Although the impact of climate change is projected to be large, many uncertainties persist, in particular with respect to impacts on livestock and grazing components, whole-farm dynamics and heterogeneous farm populations. We summarize the current understanding on impacts and vulnerability and highlight key knowledge gaps for the separate system components and the mixed farming systems as a whole. Numerous adaptation and mitigation options exist for crop–livestock systems. We provide an overview by distinguishing risk management, diversification and sustainable intensification strategies, and by focusing on the contribution to the three pillars of climate-smart agriculture. Despite the potential solutions, smallholders face major constraints at various scales, including small farm sizes, the lack of response to the proposed measures and the multi-functionality of the livestock herd. Major institutional barriers include poor access to markets and relevant knowledge, land tenure insecurity and the common property status of most grazing resources. These limit the adoption potential and hence the potential impact on resilience and mitigation. In order to effectively inform decision-making, we therefore call for integrated, system-oriented impact assessments and a realistic consideration of the adoption constraints in smallholder systems. Building on agricultural system model development, integrated impact assessments and scenario analyses can inform the co-design and implementation of adaptation and mitigation strategies.F  相似文献   
129.
With the aid of integral transforms, analytical solutions for the transport of a decay chain in homogenous porous media are derived. Unidirectional steady-state flow and radial steady-state flow in single and multiple porosity media are considered. At least in Laplace domain, all solutions can be written in closed analytical formulae. Partly, the solutions can also be inverted analytically. If not, analytical calculation of the steady-state concentration distributions, evaluation of temporal moments and numerical inversion are still possible. Formulae for several simple boundary conditions are given and visualized in this paper. The derived novel solutions are widely applicable and are very useful for the validation of numerical transport codes.  相似文献   
130.
Over the last fifteen years, large-scale mining companies have started engaging in Corporate Social Responsibility (CSR), with the aim of contributing to developing local communities affected by their operations. Large-scale mining companies, together with the World Bank, have formulated voluntary principles and benchmarks to guide these company–community relations. Recently, it has been argued that CSR is also crucial in the early stages of exploration. Nowadays, mining consultants propagate a process approach to company–community relations, from early exploration to post-mining planning.  相似文献   
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