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41.
Research in the area of media coverage on climate change communication represents one of the most prolific areas of inquiry within communication and mass communication studies. This body of literature, which ranges from empirical to critical studies, continues to expand. Much research has focused on representations of climate change causes, effects, and human actions, while some has assessed the impacts of these representations. What is broadly missing from this literature, however, is a discussion of how we might integrate media analysis into transdisciplinary collaborative research aimed at creating solutions to the social, environmental, and economic issues intertwined with climate change. Given the magnitude of problems the society and science are currently grasping with, it behooves us to understand how media studies can contribute most effectively to characterizing and solving problems. We maintain that the move toward integrating media studies into transdisciplinary collaborative research marks an essential transition for environmental communication in general, but climate change communication in particular, given the urgency and magnitude of creating meaningful adaptation and mitigation strategies to address this pressing, complex challenge. Drawing on our work as part of a large transdisciplinary sustainability science team, we provide a case study for understanding what collaborations are key to moving media studies into a transdisciplinary context and the key opportunities and barriers that come along with that move. We argue that media studies must increasingly engage directly in collaboration with other researchers, stakeholders, and communities to serve on-the-ground decision-making and enhance society's ability to take action.  相似文献   
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Abstract

This project demonstrated the biofiltration of a trichloroethylene (TCE)-contaminated airstream generated by air stripping groundwater obtained from several wells located at the Anniston Army Depot, Anniston, AL. The effects of several critical process variables were investigated to evaluate technical and economic feasibility, define operating limits and preferred operating conditions, and develop design information for a full-scale biofilter system. Long-term operation of the demonstration biofilter system was conducted to evaluate the performance and reliability of the system under variable weather conditions. Propane was used as the primary substrate necessary to induce the production of a nonspecific oxygenase. Results indicated that the process scheme used to introduce propane into the biofiltration system had a significant impact on the observed TCE removal efficiency. TCE degradation rates were dependent on the inlet contaminant concentration as well as on the loading rate. No microbial inhibition was observed at inlet TCE concentrations as high as 87 parts per million on a volume basis.  相似文献   
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Land capability classification systems define and communicate biophysical limitations on land use, including climate, soils and topography. They can therefore provide an accessible format for both scientists and decision-makers to share knowledge on climate change impacts and adaptation. Underlying such classifications are complex interactions that require dynamic spatial analysis, particularly between soil and climate. These relationships are investigated using a case study on drought risk for agriculture in Scotland, which is currently considered less significant than wetness-related issues. The impact of drought risk is assessed using an established empirical system for land capability linking indicator crops with water availability. This procedure is facilitated by spatial interpolation of climate and soil profile data to provide soil moisture deficits and plant available water on a regular 1-km grid. To evaluate potential impacts of future climate change, land capability classes are estimated using both large-scale ensemble (multi-simulation) data from the HadRM3 regional climate model and local-scale weather generator data (UKCP09) derived from multiple climate models. Results for the case study suggest that drought risk is likely to have a much more significant influence on land use in the future. This could potentially act to restrict the range of crops grown and hence reduce land capability in some areas unless strategic-level adaptation measures are developed that also integrate land use systems and water resources with the wider environment.  相似文献   
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Biomarkers comprising activities of biotransformation enzymes (ethoxyresorufin-O-deethylase -EROD-, dibenzylfluorescein dealkylase -DBF-, glutathione S-transferase -GST), antioxidant enzymes (glutathione reductase -GR- and glutathione peroxidase -GPX), lipid peroxidation -LPO- and DNA strand breaks were analyzed in the clam Ruditapes philippinarum caged at Cádiz Bay, Santander Bay and Las Palmas de Gran Canaria (LPGC) Port (Spain). Sediments were characterized. Digestive gland was the most sensitive tissue to sediment contamination. In Cádiz Bay, changes in LPO regarding day 0 were related with metals. In LPGC Port, DBF, EROD, and GST activity responses suggested the presence of undetermined contaminants which might have led to DNA damage. In Santander Bay, PAHs were related with EROD activity, organic and metal contamination was found to be associated with GR and GST activities and DNA damage presented significant (p < 0.05) induction. R. philippinarum was sensitive to sediment contamination at biochemical level. Biomarkers allowed chemical exposure and sediment quality assessment.  相似文献   
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Different degradation methods have been applied to assess the suitability of advanced oxidation process (AOPs) to promote mineralization of imazethapyr [(RS)-5-ethyl-2-(4-isopropyl-4-methyl-5-oxo-2-imidazolin-2-yl)nicotinic acid], a widely used imidazolinone class herbicide, the persistence of which has been demonstrated in surface and ground waters destined to human uses. Independent of the oxidation process assessed, the decomposition of imazethapyr always followed a pseudo-first order kinetic. The direct UV-irradiation (UV) of the herbicide as well as its oxidation with ozone (O?), and hydrogen peroxide tied to UV-irradiation (H?O?/UV) were sufficiently slow to permit the identification of intermediate products, the formation pathway of which has been proposed. Ozonation joined to UV-irradiation (O?/UV), ozonation joined to titanium dioxide photo-catalysis (TiO?/UV+O?), sole photo-catalysis (TiO?/UV), and photo-catalysis reinforced with hydrogen peroxide-oxidation (TiO?/UV+H?O?) were characterized by a faster degradation and rapid formation of a lot of small molecules, which were quickly degraded to complete mineralization. The most effective oxidation methods were those using titanium dioxide photo-catalysis enhanced either by ozonation or hydrogen peroxide. Most of all, these last processes were useful to avoid the development of dangerous by-products.  相似文献   
49.

Ecosystem research focuses on goods and services, thereby ascribing beneficial values to the ecosystems. Depending on the context, however, outputs from ecosystems can be both positive and negative. We examined how provisioning services of wild animals and plants can switch between being services and disservices. We studied agricultural communities in Laos to illustrate when and why these switches take place. Government restrictions on land use combined with economic and cultural changes have created perceptions of rodents and plants as problem species in some communities. In other communities that are maintaining shifting cultivation practices, the very same taxa were perceived as beneficial. We propose conversion factors that in a given context can determine where an individual taxon is located along a spectrum from ecosystem service to disservice, when, and for whom. We argue that the omission of disservices in ecosystem service accounts may lead governments to direct investments at inappropriate targets.

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50.
Dendrimer-functionalized multi-walled carbon nanotubes (MWCNT) for heavy metal ion removal from wastewaters were developed. Triazole dendrimers (TD) were built directly onto the carbon nanotube surface by successive click chemistry reactions affording the zero- and first-generation dendrimer-functionalized MWCNT (MWCNT-TD1 and MWCNT-TD2). The Moedritzer-Irani reaction carried out on the amino groups present on the MWCNT-TD2 sample gave the corresponding α-aminophosphonate nanosystem MWCNT-TD2P. Both MWCNT-TD2 and MWCNT-TD2P nanosystems have been characterized by physical, chemical, and morphological analyses. Their chelating abilities towards the toxic metal ions Pb2+, Hg2+, and Ni2+ and the harmless Ca2+ ion have been experimentally evaluated in the two different sets of experiments and at the salt concentrations of 1 mg/mL or 1 μg/mL by inductively coupled plasma mass spectrometry (ICP-MS). The results of these studies pointed out the interesting chelating behavior for the phosphonated nanosystem towards the Hg2+ ion. The complexation mode of the best chelating system MWCNT-TD2P with mercury was investigated through density functional theory (DFT) calculations, suggesting a chelation mechanism involving the two oxygen atoms of the phosphate group. The synthesized dendrimers, supported on the multi-walled carbon nanotubes, have shown the potential to be used for the selective toxic metal ion removal and recovery.  相似文献   
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