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An aggregated farm-level index, the Agri-environmental Footprint Index (AFI), based on multiple criteria methods and representing a harmonised approach to evaluation of EU agri-environmental schemes is described. The Index uses a common framework for the design and evaluation of policy that can be customised to locally relevant agri-environmental issues and circumstances. Evaluation can be strictly policy-focused, or broader and more holistic in that context-relevant assessment criteria that are not necessarily considered in the evaluated policy can nevertheless be incorporated. The Index structure is flexible, and can respond to diverse local needs. The process of Index construction is interactive, engaging farmers and other relevant stakeholders in a transparent decision-making process that can ensure acceptance of the outcome, help to forge an improved understanding of local agri-environmental priorities and potentially increase awareness of the critical role of farmers in environmental management. The structure of the AFI facilitates post-evaluation analysis of relative performance in different dimensions of the agri-environment, permitting identification of current strengths and weaknesses, and enabling future improvement in policy design. Quantification of the environmental impact of agriculture beyond the stated aims of policy using an ‘unweighted’ form of the AFI has potential as the basis of an ongoing system of environmental audit within a specified agricultural context.  相似文献   
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During the past 20 years of research in occupational safety and health (OSH), major contributions have been made by psychology in general, foremost German work and organizational psychology. This is the result of an empirical study with 216 scientific projects that were analyzed by content, and 32 interviews on OSH with experts on science, as well as in professional occupations and federations. Its sound methodological and theoretical approach has helped work and organizational psychology to embody itself as a driving force of OSH. The research focuses on the development of tools for job analysis, striving for the valid diagnosis of occupational hazards and mental load. Consequently, work and organizational psychology provides a solid foundation for deriving human and personality ameliorating organizational measures. Among the predominant means of intervention are training in coping with stress, behavioral training and modeling, health circles, and the arrangement of environments sensitive to occupational load. Major deficits in the field of research show up within evaluation and transfer as well as within quality control of the developed diagnostic and devices regarding intervention. Future scientific effort by means of application-orientated methods is vital to detect and overcome effectively a mounting mental load in the occupational world.  相似文献   
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The pygidial gland secretion of the rove beetle genera Stenus Latreille and Dianous Leach is composed of pyridine and piperidine-derived alkaloids and several terpene compounds. Two-choice bioassays with ants and fish, as well as agar diffusion assays, revealed that the secretion compounds are capable of deterring predators and protecting the beetles from infestation with microorganisms. In addition, the beetles use the secretion for rapid movements on the water surface, a process called skimming. Thus, originally developed to chemically defend the sensitive unprotected abdomen from predator attacks, the secretion of recent Steninae can be designated as multifunctional. Four of the alkaloid compounds occur as different configurational isomers in the secretion. Two-choice tests showed that ants discriminate between stereoisomers of stenusine, while there was no effect visible on bacteria in agar diffusion assays. Furthermore, there are evolutionary trends within the Steninae concerning the secretion composition, as some of the alkaloids primarily occur in phylogenetically basal species, while others are mainly restricted to derived species.  相似文献   
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Members of the United Nations Economic Commission for Europe (UN-ECE) signed a legally binding protocol on persistent organic pollutants (POPs) in February 1998 under the Convention on Long-Range Transboundary Air Pollution. A treaty that intends to control the production, import, export, disposal and use of toxic chemicals that persist for decades in the environment has been formally signed at a conference in May 2001 in Stockholm. The 2001 POP treaty, like the 1998 LRTAP POP protocol, contains a provision on adding further chemicals to the initial group of twelve or fifteen. The occurrence of a compound or a group of compounds in so called remote and pristine areas, e.g. in the Artic or in the Southern Hemisphere, proves its stability under the chemical and biological conditions of the environment. Compounds identified in this way, in samples taken primarily in very remote regions of the planet, are classified by their environmental fate and global distribution as persistent organic pollutants (POPs), regardless of any political assessments.  相似文献   
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Rove beetles of the genus Stenus Latreille and the genus Dianous Leach possess pygidial glands containing a multifunctional secretion of piperidine and pyridine-derived alkaloids as well as several terpenes. One important character of this secretion is the spreading potential of its different compounds, stenusine, norstenusine, 3-(2-methyl-1-butenyl)pyridine, cicindeloine, α-pinene, 1,8-cineole and 6-methyl-5-heptene-2-one. The individual secretion composition enables the beetles to skim rapidly and far over the water surface, even when just a small amount of secretion is emitted. Ethological investigations of several Stenus species revealed that the skimming ability, skimming velocity and the skimming behaviour differ between the Stenus species. These differences can be linked to varied habitat claims and secretion saving mechanisms. By means of tensiometer measurements using the pendant drop method, the spreading pressure of all secretion constituents as well as some naturally identical beetle secretions on the water surface could be established. The compound 3-(2-methyl-1-butenyl)pyridine excelled stenusine believed to date to be mainly responsible for skimming relating to its surface activity. The naturally identical secretions are not subject to synergistic effects of the single compounds concerning the spreading potential. Furthermore, evolutionary aspects of the Steninae’s pygidial gland secretion are discussed.  相似文献   
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Archetypical patterns and trajectories of land systems in Europe   总被引:1,自引:0,他引:1  
Regional Environmental Change - Assessments of land-system change have dominantly focused on conversions among broad land-use categories, whereas intensity changes within these categories have...  相似文献   
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