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541.
This research uses a social identity analysis to predict employee creativity. We hypothesized that team identification leads to greater employee creative performance, mediated by the individual's creative effort. We hypothesized that leader inspirational motivation as well as leader team prototypicality would moderate the relationship between identification and creative effort. Consistent with these predictions, data based on 115 matched pairs of employee‐leader ratings in a research and development context showed an indirect relationship between team identification and creative performance mediated by creative effort. The analyses also confirmed the expected moderated relationships. Leader inspirational motivation enhanced the positive association between identification and creative effort, especially when leader prototypicality was high. We discuss the value of social identity analyses of employee creativity and of the integration of social identity and transformational leadership analyses. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
542.
The interaction of parameters determining the potential emissions of two different mechanically-biologically pretreated municipal solid wastes (MBT wastes) is elucidated in this work. The origins of the wastes are Germany and Sweden. By means of lab-scale experiments, increased stabilisation through composting is preferably determined by a decrease in respiration activity. Concurrently, the stabilisation is verified for the leachates by a decrease in COD, DOC, and BOD(5). Total organic carbon content reflects stabilisation less accurately. FT-IR and thermal analytical methods add valuable information about the state of degradation, especially when several distinct thermal parameters are taken into account. Mobility of Cr, Ni, Pb, and Zn produced by a batch leaching test with deionized water is reduced by the pretreatment of both materials. Mobility of copper unambiguously increased. A principle component analysis (PCA) of membrane fractionated leachates indicates an affinity of Cu to mobile humic acids or dissolved organic carbon. High Cr, Zn, and Ni contents in the solid co-occur with high contents of solid humic acids. To a lesser extent, this is also true for solid Cd, Cu, and Pb contents. Due to differences in required landfilling conditions, actual emissions and after-care phase length will depend on whether each waste is landfilled in Germany or Sweden.  相似文献   
543.
Crop-raiding elephants affect local livelihoods, undermining conservation efforts. Yet, crop-raiding patterns are poorly understood, making prediction and protection difficult. We hypothesized that raiding elephants use corridors between daytime refuges and farmland. Elephant counts, crop-raiding records, household surveys, Bayesian expert system, and least-cost path simulation were used to predict four alternative categories of daily corridors: (1) footpaths, (2) dry river beds, (3) stepping stones along scattered small farms, and (4) trajectories of shortest distance to refuges. The corridor alignments were compared in terms of their minimum cumulative resistance to elephant movement and related to crop-raiding zones quantified by a kernel density function. The “stepping stone” corridors predicted the crop-raiding patterns. Elephant presence was confirmed along these corridors, demonstrating that small farms located between refuges and contiguous farmland increase habitat connectivity for elephant. Our analysis successfully predicted elephant occurrence in farmland where daytime counts failed to detect nocturnal presence. These results have conservation management implications.  相似文献   
544.
Excessive summer drying and reduced growing season length are expected to reduce European crop yields in future. This may be partly compensated by adapted crop management, increased CO2 concentration and technological development. For food security, changes in regional to continental crop yield variability may be more important than changes in mean yields. The assessment of changes in regional and larger scale crop variability requires high resolution and spatially consistent future weather, matching a specific climate scenario. Such data could be derived from regional climate models (RCMs), which provide changes in weather patterns. In general, RCM output is heavily biased with respect to observations. Due to the strong nonlinear relation between meteorological input and crop yields, the application of this biased output may result in large biases in the simulated crop yield changes. The use of RCM output only makes sense after sufficient bias correction. This study explores how RCM output can be bias corrected for the assessment of changes in European and subregional scale crop yield variability due to climate change. For this, output of the RCM RACMO of the Royal Netherlands Meteorological Institute was bias corrected and applied within the crop simulation model WOrld FOod STudies to simulate potential and water limited yields of three divergent crops: winter wheat, maize and sugar beets. The bias correction appeared necessary to successfully reproduce the mean yields as simulated with observational data. It also substantially improved the year-to-year variability of seasonal precipitation and radiation within RACMO, but some bias in the interannual variability remained. This is caused by the fact that the applied correction focuses on mean and daily variability. The interannual variability of growing season length, and as a consequence the potential yields too, appeared even deteriorated. Projected decrease in mean crop yields is well in line with earlier studies. No significant change in crop yield variability was found. Yet, only one RCM is analysed in this study, and it is recommended to extend this study with more climate models and a slightly adjusted bias correction taking into account the variability of larger time scales as well.  相似文献   
545.
Climate change will have an impact on various sectors, such as housing, infrastructure, recreation and agriculture. Climate change may change spatial demands. For example, rising temperatures will increase the need for recreation areas, and areas could be assigned for water storage. There is a growing sense that, especially at the local scale, spatial planning has a key role in addressing the causes and impacts of climate change. This paper promotes an approach to help translate information on climate change impacts into a guiding model for adaptive spatial planning. We describe how guiding models can be used in designing integrated adaptation strategies. The concept of guiding models has been developed in the 1990s by Tjallingii to translate the principles of integrated water management in urban planning. We have integrated information about the present and future climate change and set up a climate adaptation guiding model approach. Making use of climate adaptation guiding models, spatial planners should be able to better cope with complexities of climate change impacts and be able to translate these to implications for spatial planning. The climate adaptation guiding model approach was first applied in the Zuidplaspolder case study, one of the first major attempts in the Netherlands to develop and implement an integrated adaptation strategy. This paper demonstrates how the construction of climate adaptation guiding models requires a participatory approach and how the use of climate adaptation guiding models can contribute to the information needs of spatial planners at the local scale, leading to an increasing sense of urgency and integrated adaptation planning process.  相似文献   
546.
We determined whether climate change in the Netherlands has caused phenological changes since 1868. We analysed over 150,000 plant phenological observations of 320 plant species, obtained by four volunteer networks and one series collected by Mr. Braaksma. With the network data, we compared the timing of life cycle events in three different periods: 1894–1932 (Period 1), 1940–1968 (Period 2) and 2001–2010 (Period 3). For the Braaksma series, we compared the periods 1953–1968 (Period A) with 1969–1992 (Period B). We conclude that until the beginning of the 1990s, there have been no significant changes in the timing of life cycle events. The timing of life cycle events in Period 3 showed an average advance of flowering, leaf unfolding and fruit ripening of 14 days compared with Period 1 and 13 days compared with Period 2. Some species have advanced up to over 35 days. Autumn events occurred up to an average of 7 days later in Period 3 compared to earlier periods. This study shows that, based on network data, changes in climate explain on average 66 % of the variation in timing of phenological events from year to year. For the Braaksma data, this is 38 %. The expected future changes in climate will undoubtedly result in a further lengthening of the growing season. We believe that phenological networks, supported by thousands of volunteers, are needed to quantify, analyse, predict and communicate these phenological changes so various sectors in society can adapt to these changes and prevent significant socio-economic impacts.  相似文献   
547.
Climate change impacts affecting coastal areas, such as sea-level rise and storm surge events, are expected to have significant social, economic and environmental consequences worldwide. Ongoing population growth and development in highly urbanised coastal areas will exacerbate the predicted impacts on coastal settlements. Improving the adaptation potential of highly vulnerable coastal communities will require greater levels of planning and policy integration across sectors and scales. However, to date, there is little evidence in the literature which demonstrates how climate policy integration is being achieved. This paper contributes to this gap in knowledge by drawing on the example provided by the process of developing cross-sectoral climate change adaptation policies and programmes generated for three coastal settlement types as part of the South East Queensland Climate Adaptation Research Initiative (SEQCARI), a 3-year multi-sectoral study of climate change adaptation options for human settlements in South East Queensland, Australia. In doing so, we first investigate the benefits and challenges to cross-sectoral adaptation to address climate change broadly and in coastal areas. We then describe how cross-sectoral adaptation policies and programmes were generated and appraised involving the sectors of urban planning and management, coastal management, emergency management, human health and physical infrastructure as part of SEQCARI. The paper concludes by discussing key considerations that can inform the development and assessment of cross-sectoral climate change adaptation policies and programmes in highly urbanised coastal areas.  相似文献   
548.
This paper gives an overview of management considerations required for better control of deicing chemicals in the unsaturated zone at sites with winter maintenance operations in cold regions. Degradable organic deicing chemicals are the main focus. The importance of the heterogeneity of both the infiltration process, due to frozen ground and snow melt including the contact between the melting snow cover and the soil, and unsaturated flow is emphasised. In this paper, the applicability of geophysical methods for characterising soil heterogeneity is considered, aimed at modelling and monitoring changes in contamination. To deal with heterogeneity, a stochastic modelling framework may be appropriate, emphasizing the more robust spatial and temporal moments. Examples of a combination of different field techniques for measuring subsoil properties and monitoring contaminants and integration through transport modelling are provided by the SoilCAM project and previous work. Commonly, the results of flow and contaminant fate modelling are quite detailed and complex and require post-processing before communication and advising stakeholders. The managers’ perspectives with respect to monitoring strategies and challenges still unresolved have been analysed with basis in experience with research collaboration with one of the case study sites, Oslo airport, Gardermoen, Norway. Both scientific challenges of monitoring subsoil contaminants in cold regions and the effective interaction between investigators and management are illustrated.  相似文献   
549.
550.
Considering the important role that surface waters serve for drinking water production, it is important to know if these resources are under the impact of contaminants. Apart from environmental pollutants such as pesticides, compounds such as (xeno)estrogens have received al lot of research attention and several large monitoring campaigns have been carried out to assess estrogenic contamination in the aquatic environment. The introduction of novel in vitro bioassays enables researchers to study if – and to what extent – water bodies are under the impact of less-studied (synthetic) hormone active compounds. The aim of the present study was to carry out an assessment on the presence and extent of glucocorticogenic activity in Dutch surface waters that serve as sources for drinking water production. The results show glucocorticogenic activity in the range of <LOD – 2.4 ng dexamethasone equivalents L−1 (dex EQs) in four out of eight surface waters. An exploratory time-series study to obtain a more complete picture of the yearly average of fluctuating glucocorticogenic activities at two sample locations demonstrated glucocorticogenic activities ranging between <LOD – 2.7 ng dex EQs L−1. Although immediate human health effects are unlikely, the environmental presence of glucocorticogenic compounds in the ng L−1 range compels further environmental research and assessment.  相似文献   
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