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131.
This paper provides an account of urban greenhouse gas (GHG) emissions from 40 countries in Europe and examines covariates of emissions levels. We use a “top-down” analysis of emissions as spatially reported in the Emission Dataset for Global Atmospheric Research supplemented by Carbon Monitoring for Action from 1153 European cities larger than 50 000 population in 2000 (comprising >81 % of the total European urban population). Urban areas are defined spatially and demographically by the Global Rural Urban Mapping Project. We compare these results with “bottom-up” carbon accounting method results for cities in the region. Our results suggest that direct (Scopes 1 and 2) GHG emissions from urban areas range between 44 and 54 % of total anthropogenic emissions for the region. While individual urban GHG footprints vary from bottom-up studies, both the mean differences and the regional energy-related GHG emission share support previous findings. Correlation analysis indicates that the urban GHG emissions in Europe are mainly influenced by population size, density, and income and not by biophysical conditions. We argue that these data and methods of analysis are best used at the regional or higher scales.  相似文献   
132.
New concerns about biodiversity, ecosystem services and human health triggered several new regulations increasing the need for sound ecotoxicological risk assessment. The PEER network aims to share its view on the research issues that this challenges. PEER scientists call for an improved biologically relevant exposure assessment. They promote comprehensive effect assessment at several biological levels. Biological traits should be used for Environmental risk assessment (ERA) as promising tools to better understand relationships between structure and functioning of ecosystems. The use of modern high throughput methods could also enhance the amount of data for a better risk assessment. Improved models coping with multiple stressors or biological levels are necessary to answer for a more scientifically based risk assessment. Those methods must be embedded within life cycle analysis or economical models for efficient regulations. Joint research programmes involving humanities with ecological sciences should be developed for a sound risk management.  相似文献   
133.
Burnout is considered to be a long‐term reaction to occupational stress. It is characterized by emotional exhaustion, depersonalization, and diminished personal accomplishment. The most widely used instrument to measure burnout is the Maslach Burnout Inventory (MBI), developed by Maslach and Jackson (1986). From this instrument, Schaufeli and van Dierendonck (1995a) developed a somewhat modified Dutch version: the MBI‐NL. Burnout among dentists has hardly been studied. Since the professions that the MBI‐NL was developed upon are quite different from dentistry, the aim of this study was to test the three‐factor structure of the MBI‐NL against alternative structures among dentists. Both principal components analysis (PCA) and confirmatory factor analysis (CFA) were examined in a representative sample of 709 Dutch general dental practitioners (75 per cent response rate). The three‐factor structure shows the best fit to the underlying data, while other psychometric qualities are very satisfactory. It is concluded that the three‐factor structure of the MBI‐NL is superior to alternative structures, and that the MBI‐NL is a highly suitable instrument to measure burnout among dentists. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   
134.
This paper examines an issue that is becoming increasingly relevant as the pressures of a warming planet, changing climate and changing ecosystems ramp up. The broad context for the paper is the intragenerational, intergenerational, and interspecies equity implications of changing the climate and the value orientations of adapting to such change. In addition, the need to stabilize the planetary climate by urgent mitigation of change factors is a foundational ethical assumption. In order to avoid further animal and plant extinctions, or at the very least, their increased vulnerability to becoming rare and endangered; the systematic assisted colonization of “at risk” species is being seriously considered by scientists and managers of biodiversity. The more practical aspects of assisted colonization have been covered in the conservation biology literature; however, the ethical implications of such actions have not been extensively examined. Our discussion of the value issues, using a novel case study approach, will rectify the limited ethical analysis of the issue of assisted colonization of species in the face of climate change pressures. Beyond sustainability ethics, both animal and environmental ethical approaches will be used and intrinsic versus instrumental value orientations in the literature shall form the basis of our discussion. After the application of all the ethical approaches to the case studies, we conclude that without mitigation and the prospect of a future stable climate, assisted colonization will be involved in an inherently unethical process and a “move and lose it” outcome. With mitigation, there is wide-ranging ethical support for assisted colonization.  相似文献   
135.
ABSTRACT

Bioeconomy is a new political and economic buzzword that frames many proposed pathways to sustainable regional development in Europe, particularly in rural, biomass rich areas. Dissected by research into various strands, visions, shades of “green” and presented by bioeconomy stakeholders through regional examples and self-promoting bio-clusters, the socio-spatial processes of regional assemblages are often ignored in these accounts. Based on a prominent Finnish example, this case study employs the concept of bioassemblage to display the socio-spatial positionalities of regional bioeconomy development in the places of materialisation. Furthermore, it ties the spatial (re-)production of bioassemblages to their role as bioeconomy policy translation loops and consequently provides insights into the processes of bioeconomy policy mobility, translation and mutation. Examining the positionalities in a bioassemblage presents a complex and frequently shifting local environment accompanied by unequal power topologies and means of territorialisation. Shallow policy narratives create problematic mismatches between the “best-practices” employed by policy makers and regional bioeconomy materialisation in the places themselves. While the study makes no assumption on the sustained future of bioeconomy development, it shows that current processes enable the externalisation of risks at industrial sites, restrict wider participation and discredit the important role of institutional actors in development.  相似文献   
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138.
Triolein-containing semipermeable membrane devices (SPMDs) were employed as passive samplers to provide data on the bioavailable fraction of organic, waterborne, organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs) and polynuclear aromatic hydrocarbons (PAHs) in streams flowing through a highly polluted industrial area of Bitterfeld in Saxony-Anhalt, Germany. The contamination of the region with organic pollutants originates in wastewater effluents from the chemical industry, from over one-hundred years of lignite exploitation, and from chemical waste dumps. The main objective was to characterise time-integrated levels of dissolved contaminants, to use them for identification of spatial trends of contamination, and their relationship to potential pollution sources. SPMDs were deployed for 43 days in the summer of 1998 at four sampling sites. The total concentration of pollutants at sampling sites was found to range from a low of 0.8 microgram/SPMD to 25 micrograms/SPMD for PAHs, and from 0.4 microgram/SPMD to 22 micrograms/SPMD for OCPs, respectively. None of the selected PCB congeners was present at quantifiable levels at any sampling site. A point source of water pollution with OCPs and PAHs was identified in the river system considering the total contaminant concentrations and the distribution of individual compounds accumulated by SPMDs at different sampling sites. SPMD-data was also used to estimate average ambient water concentrations of the contaminants at each field site and compared with concentrations measured in bulk water extracts. The truly dissolved or bioavailable portion of contaminants at different sampling sites ranged from 4% to 86% for the PAHs, and from 8% to 18% for the OCPs included in the estimation. The fraction of individual compounds found in the freely dissolved form can be attributed to the range of their hydrophobicity. In comparison with liquid/liquid extraction of water samples, the SPMD method is more suitable for an assessment of the background concentrations of hydrophobic organic contaminants because of substantially lower method quantification limits. Moreover, contaminant residues sequestered by the SPMDs represent an estimation of the dissolved or readily bioavailable concentration of hydrophobic contaminants in water, which is not provided by most analytical approaches.  相似文献   
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140.
Climate change: linking adaptation and mitigation through agroforestry   总被引:4,自引:0,他引:4  
Agriculture is the human enterprise that is most vulnerable to climate change. Tropical agriculture, particularly subsistence agriculture is particularly vulnerable, as smallholder farmers do not have adequate resources to adapt to climate change. While agroforestry may play a significant role in mitigating the atmospheric accumulation of greenhouse gases (GHG), it also has a role to play in helping smallholder farmers adapt to climate change. In this paper, we examine data on the mitigation potential of agroforestry in the humid and sub-humid tropics. We then present the scientific evidence that leads to the expectation that agroforestry also has an important role in climate change adaptation, particularly for small holder farmers. We conclude with priority research questions that need to be answered concerning the role of agroforestry in both mitigation and adaptation to climate change.  相似文献   
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