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71.
This study represents a first attempt at applying a fuzzy inference system (FIS) and an adaptive neuro-fuzzy inference system (ANFIS) to the field of aquatic biomonitoring for classification of the dosage and time of benzo[a]pyrene (BaP) injection through selected biomarkers in African catfish (Clarias gariepinus). Fish were injected either intramuscularly (i.m.) or intraperitoneally (i.p.) with BaP. Hepatic glutathione S-transferase (GST) activities, relative visceral fat weights (LSI), and four biliary fluorescent aromatic compounds (FACs) concentrations were used as the inputs in the modeling study. Contradictory rules in FIS and ANFIS models appeared after conversion of bioassay results into human language (rule-based system). A “data trimming” approach was proposed to eliminate the conflicts prior to fuzzification. However, the model produced was relevant only to relatively low exposures to BaP, especially through the i.m. route of exposure. Furthermore, sensitivity analysis was unable to raise the classification rate to an acceptable level. In conclusion, FIS and ANFIS models have limited applications in the field of fish biomarker studies.  相似文献   
72.
Effective and efficient information dissemination is crucial for a successful management of coasts and beaches. Almost all coastal management activities use Internet portals to provide electronic accessibility of data and information. In this respect, we have analyzed web tracking data and costs to investigate the effectiveness and efficiency of two coastal management web portals. Indicators for the visiting quality, the volume and characteristics of the information flow and the associated costs were combined. The results show that mainly professional users were attracted by the two investigated online coastal management information offers. Furthermore, the coastal management contents were mainly relevant on regional scale. The results indicate that it is not enough to provide various information, instead it further needs also efforts to disseminate this information to a broader public. Specific preparation and presentation of information for the target groups would lead to an active dissemination process. The investigation of the costs shows that an increasing efficiency of information dissemination via the Internet goes together with the long term use of the information infrastructure. Therefore large coastal management web portals need runtimes of several years. The applied method combined and simplified actual used web analytic methods to allow valuable insights into the information dissemination of coastal management web portals. In this way the method can be used to help coastal decision makers or other practitioners to screen their web presence in the background of information supply and demand for all visitor groups they want to reach.  相似文献   
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Ambio - The phenomenon of collective action and the origin of collective action problems have been extensively and systematically studied in the social sciences. Yet, while we have substantial...  相似文献   
75.
Zusammenfassung  Um zu einer sachgerechten und nachvollziehbar quantifizierbaren Beurteilung der m?glichen Gesundheitsbelastungen des Menschen durch Schadstoffe zu gelangen, ist es von grundlegender Bedeutung dessen ?u?ere Schadstoffexposition absch?tzen zu k?nnen. Um die Durchführung derartiger Absch?tzungen zu erm?glichen, werden nutzergruppen- und expositionsszenariospezifisch orale, inhalative und dermale Aufnahmeraten für die Kontaktmedien Boden, Pflanzen aus Haus- und Schreberg?rten, Trinkwasser, Staub, Hausstaub und Innenraumluft vorgeschlagen. Diese Aufnahmeraten dienen, gemeinsam mit gemessenen oder berechneten Schadstoffkonzentrationen in den entsprechenden Kontaktmedien, zur Absch?tzung der von Menschen aufgenommenen Schadstoffdosen und erm?glichen durch einen Vergleich mit tolerierbaren Schadstoffdosen eine stoff-, nutzungs- und standortbezogene Beurteilung von Schadstoffexpositionen, auch für komplexe Nutzungen.   相似文献   
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The stringency of policies needed to meet a climate target is influenced by uncertain oil prices because price changes cause emission changes, making the robustness of climate policy instruments important. As a result of its dependence on oil, emissions from the transport sector are particularly sensitive to oil price changes. We use a computable general equilibrium model to study the effects of including the transport sector in the EU??s emissions trading scheme under three future oil price scenarios. Our results show that there are potentially significant welfare gains from including transportation in the emissions trading scheme because the system as a whole helps absorb required changes in climate policy to meet the overall EU cap on emissions. There is, however, a cost in terms of somewhat greater permit price uncertainty.  相似文献   
78.
The quality of regionalizations can only be evaluated with regard to its specific purposes. In environmental monitoring, regionalizations, besides being an analysis tool, has a great importance on the selection of monitoring sites. The article describes the relationship between regionalization, selection procedure and representativeness using the example of Ecological Area Sampling (EAS) and presents the regionalization which was tested in an EAS pilot study.  相似文献   
79.
Ecological risk of chemicals is measured by the quotient of predicted no-effect concentrations and predicted exposure concentrations, which are hard to assess for manufactured nanomaterials (NMs). This paper proposes modifications to currently used models, in order to make them suitable for estimating exposure concentrations of NMs in the aquatic environment. We have evaluated the adequacy of the current guidance documents for use with NMs and conclude that nano-specific fate processes, such as sedimentation and dissolution need to be incorporated. We have reviewed the literature on sedimentation and dissolution of NMs in environmentally relevant systems. We deduce that the overall kinetics of water-sediment transport of NMs should be close to first order. The lack of data on dissolution of NMs under environmentally realistic conditions calls for a pragmatic decision on which rates to be used in modeling. We find that first order removal kinetics for dissolution seems adequate. Based on limited data from literature, probable removal rates range from 0 to 10(-4)s(-1) for sedimentation, and from 0 to 10(-5)s(-1) for dissolution. Further experimental data at environmentally relevant conditions for sedimentation and dissolution of NMs is needed.  相似文献   
80.
Reconnecting to the Biosphere   总被引:3,自引:0,他引:3  
Humanity has emerged as a major force in the operation of the biosphere, with a significant imprint on the Earth System, challenging social-ecological resilience. This new situation calls for a fundamental shift in perspectives, world views, and institutions. Human development and progress must be reconnected to the capacity of the biosphere and essential ecosystem services to be sustained. Governance challenges include a highly interconnected and faster world, cascading social-ecological interactions and planetary boundaries that create vulnerabilities but also opportunities for social-ecological change and transformation. Tipping points and thresholds highlight the importance of understanding and managing resilience. New modes of flexible governance are emerging. A central challenge is to reconnect these efforts to the changing preconditions for societal development as active stewards of the Earth System. We suggest that the Millennium Development Goals need to be reframed in such a planetary stewardship context combined with a call for a new social contract on global sustainability. The ongoing mind shift in human relations with Earth and its boundaries provides exciting opportunities for societal development in collaboration with the biosphere--a global sustainability agenda for humanity.  相似文献   
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