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941.
Based on semi-structured interviews with 31 Ohioans, this article argues that individuals who are concerned about shale energy development draw from a discursive framework that diverges dramatically from the position promoted by industrial proponents. While the oil and gas industry and its supporters largely embrace a neoliberal outlook that most closely correlates well-being with economic growth, citizens troubled by such development are guided by a more holistic perspective that links well-being to numerous interrelated non-economic elements including human health, community continuity, political empowerment, and environmental sustainability. This work contributes to an emerging understanding of how environmental change and socionatural well-being converge in the novel context of shale energy development and aims to give voice to those who cope with the direct consequences of twenty-first-century fossil fuel extraction. Approaching discourse – defined here as shared communication patterns that simultaneously reproduce and generate distinctive understandings of the world – as a dynamic arena of sociopolitical struggle, I further suggest that shale energy opponents use holistic sustainability discourse to actively or implicitly challenge neoliberal strategies for guiding thought and governing action.  相似文献   
942.
When planning interventions, water and land resource managers increasingly need to take the opinions of stakeholders into account. In the present study, stakeholders’ concerns in a multifunctional water system are assessed, with a focus on the debate about the sustainability of irrigation projects in stressed and competing water contexts. The selected case study pertains to the Segarra‐Garrigues irrigation canal (Spain), the promotion of which has generated social debate and mobilization, as well as pronouncements from European authorities for ensuring its environmental sustainability. Data was collected through semi‐structured interviews and analysed by means of a new codification system for identifying the affinities and conflicts arising from existing water demands. Results show that sustainability concepts are more present in civil society than in public administration and private services or the rural community. However, social sustainability and environmental sustainability are a priority for most stakeholders, while the economic perspective of sustainable development has been conditioned by the first two. These results can be used by relevant authorities as a first step in customizing their interventions, as they provide a clear initial idea of what stakeholder priorities are in the framework of sustainable development.  相似文献   
943.
We studied the genetic structure of the Mediterranean killifish Aphanius fasciatus. Analysis of the sequence variation in a 372-bp portion of the mitochondrial control region in 623 fish from 27 sampling sites along the species’ distributional range (Tyrrhenian coast, Sardinia, Sicily, Adriatic coast, Malta, Tunisia, and Greece) yielded 120 distinct haplotypes. Most of the haplotypes are unique, and only 15 % are shared among different populations. The high F ST value (=0.80) suggests a strong population genetic structuring. The phylogenetic analysis based on Bayesian inference, maximum likelihood and maximum parsimony, and the median-joining network show a sharp separation of the Southeastern Sicilian populations (belonging to the Hyblean region) and of the fluvial Tunisian population of Rio Melah from the others. The Adriatic, the Eastern Sicilian, and the Greek populations are well differentiated, while the group of populations from the Central-Western Mediterranean does not show a clear pattern of differentiation. Our findings indicate that the current genetic structuring of A. fasciatus reflects historical geographical patterns occurring within the Mediterranean basin from the Late Miocene to the Pleistocene. The presence of divergent evolutionary entities in the Hyblean region and the Tunisian Rio Melah supports their inclusion as target areas for the conservation of A. fasciatus.  相似文献   
944.
Five hundred and ninety-nine primary producers and consumers in the Papahānaumokuākea Marine National Monument (PMNM) (22°N–30°N, 160°W–180°W) were sampled for carbon and nitrogen stable isotope composition to elucidate trophic relationships in a relatively unimpacted, apex predator–dominated coral reef ecosystem. A one-isotope (δ13C), two-source (phytoplankton and benthic primary production) mixing model provided evidence for an average minimum benthic primary production contribution of 65 % to consumer production. Primary producer δ15N values ranged from ?1.6 to 8.0 ‰ with an average (2.1 ‰) consistent with a prevalence of N2 fixation. Consumer group δ15N means ranged from 6.6 ‰ (herbivore) to 12.1 ‰ (Galeocerdo cuvier), and differences between consumer group δ15N values suggest an average trophic enrichment factor of 1.8 ‰ Δ15N. Based on relative δ15N values, the larger G. cuvier may feed at a trophic position above other apex predators. The results provide baseline data for investigating the trophic ecology of healthy coral reef ecosystems.  相似文献   
945.
Although the effectiveness of herbivores in mitigating the effects of nutrient enrichment is well documented, few studies have examined the effects of nutrient enrichment on components of consumer fitness. Enclosures were deployed in shallow turtle grass (Thalassia testudinum) beds in Florida Bay, Florida in fall 2003, spring 2004, and fall 2004 to measure the effects of nitrogen and phosphorous enrichment on the growth, fecundity, and stoichiometry of three invertebrate epiphyte grazers commonly associated with T. testudinum. The gastropod Turbo castanea exhibited significantly greater wet weight gain and lower C:P and N:P in enriched than in ambient treatments. Although nutrient enrichment did not have any significant effects on the growth of caridean shrimp (treatment consisted of several different caridean shrimp species), their C:N was significantly lower in enriched treatments. The final size and stoichiometry of the hermit crab Paguristes tortugae was not significantly affected by nutrient enrichment, nor did nutrient enrichment significantly affect the fecundity of P. tortugae, the only grazer in which gravid individuals or egg masses were present. Our study demonstrated that nutrient enrichment of primary producers can positively affect the growth of marine invertebrate grazers and alter their stoichiometry; however, these effects were species-specific and may be dependent upon the life stage, specific diets, and/or compensatory feeding habits of the grazers.  相似文献   
946.
There is a dearth of data on the initiation activity of dimethylarsinic acid (DMA (V)), a major metabolite of the ubiquitous environmental and occupational carcinogen and toxicant, arsenic (As). The initiation activity of DMA (V) was investigated on rat hepatocarcinogenesis with liver being a major target organ for As-induced carcinogenicity. A total of 50 rats at 10 weeks old were randomly divided in a nine-week medium-term bioassay into four groups. Groups 1 and 2 received 200 ppm of DMA (V) in drinking water for four weeks while groups 3 and 4 drank only tap water until the sixth week when groups 1 and 3 were given 0.01% 2-acetylaminofluorene (2-AAF) in their diet for two weeks in the promotion stage. All animals were subjected to two-third partial hepatectomy (PH) at the seventh week. Quantitative analysis of glutathione S-transferase placental form (GST-P) positive foci in liver, a pre-neoplastic marker of rat hepatocarcinogenesis, demonstrated higher numbers in group 1 (DMA (V) + 2-AAF) than 3 (2-AAF alone) at foci consisting of two–four cells and 15 or a greater number of cells. The numbers of GST-P positive foci consisting of five–nine cells were significantly higher in group 1 than 3. Foci consisting of 10–14 cells were also higher but not significantly different. The GST-P positive foci were apparently similar in groups 2 and 4. Expression of total GST-P positive foci was significantly higher in group 1 compared to 2, 3 or 4. The proliferating cell nuclear antigen (PCNA) test performed to clarify the apparent trend of GST-P data revealed significantly higher PCNA index in group 1. Data indicate weak initiation potential of DMA (V) and for the first time appear to provide evidence for initiation activity in DMA (V)-induced hepatocarcinogenesis in rats.  相似文献   
947.
This study aimed to explore the adoption of environmental standards in Australia, focusing on ISO 14001. The authors used purposive sampling to select a group of ISO 14001 certified and a group of ISO 14001 non-certified companies. Data were collected through a combination of website searches and content analysis. The study found that, overall, 92.9% of the ISO 14001 certified compared to 78.4% of the ISO 14001 non-certified companies promoted their environmental commitment through various methods. In addition, 33.4% of ISO 14001 non-certified companies (compared to 19.2% of certified companies) used their environmental engagement activities as a marketing tool. Second, 80.9% of ISO 14001 certified companies' and 26.7% of the non-certified companies' reports are easy to find and are clearly stated. The study concludes that Australian companies engage in similar environmental activities irrespective of whether they are ISO 14001 certified or not. Both management and research implications of the study's findings are presented.  相似文献   
948.
Kristiana I  Joll C  Heitz A 《Chemosphere》2011,83(5):661-667
The removal of organic precursors of disinfection by-products (DBPs), i.e. natural organic matter (NOM), prior to disinfection and distribution is considered as the most effective approach to minimise the formation of DBPs. This study investigated the impact of the addition of powdered activated carbon (PAC) to an enhanced coagulation treatment process at an existing water treatment plant on the efficiency of NOM removal, the disinfection behaviour of the treated water, and the water quality in the distribution system. This is the first comprehensive assessment of the efficacy of plant-scale application of PAC combined with enhanced coagulation on an Australian source water. As a result of the PAC addition, the removal of NOM improved by 70%, which led to a significant reduction (80-95%) in the formation of DBPs. The water quality in the distribution system also improved, indicated by lower concentrations of DBPs in the distribution system and better maintenance of disinfectant residual at the extremities of the distribution system. The efficacy of the PAC treatment for NOM removal was shown to be a function of the characteristics of the NOM and the quality of the source water, as well as the PAC dose. PAC treatment did not have the capacity to remove bromide ion, resulting in the formation of more brominated DBPs. Since brominated DBPs have been found to be more toxic than their chlorinated analogues, their preferential formation upon PAC addition must be considered, especially in source waters containing high concentrations of bromide.  相似文献   
949.
Temporal trends of polyfluoroalkyl compounds (PFCs) were examined in grey seal (Halichoerus grypus) liver from the Baltic Sea over a period of 35 years (1974-2008). In total, 17 of 43 PFCs were found, including the perfluoroalkyl sulfonates (C4-C10 PFSAs), perfluorooctanesulfinate (PFOSi), long chain perfluoroalkyl carboxylates (C7-C14 PFCAs), and perfluoroalkyl sulfonamides (i.e., perfluorooctane sulfonamide (FOSA) and N-ethyl perfluorooctane sulfonamide (EtFOSA)), whereas saturated and unsaturated fluorotelomer carboxylates, shorter chain PFCAs and perfluoroalkyl phosphonic acids were not detected. Perfluorooctane sulfonate (PFOS) was the predominant compound (9.57-1444 ng g−1 wet weight (ww)), followed by perfluorononanoate (PFNA, 0.47-109 ng g−1 ww). C6-C8 PFSAs, PFOSi and C7-C13 PFCAs showed statistically significant increasing concentrations between 1974 and 1997, with a peak in 1997 and then decreased or levelled off (except for C12 and C13 PFCAs). FOSA had a different temporal trend with a maximum in 1989 followed by significant decreasing concentrations until 2008. Toxicological implications for grey seals are limited, but the maximal PFOS concentration found in this study was about 40 times lower than the predicted lowest observed effect concentrations (LOEC). The statistically significant decreasing concentrations or levelling off for several PFCs in the relative closed marine ecosystem of the Baltic Sea indicate a rapidly responding to reduced emissions to the marine environment. However, the high concentrations of PFOS and continuing increasing concentrations of the longer chain PFCAs (C12-C14) shows that further work on the reduction of environmental emissions of PFCs are necessary.  相似文献   
950.
Development of stress markers for the invader freshwater zebra mussel (Dreissena polymorpha) is of great interest for both conservation and biomonitoring purposes. Gene expression profiles of several putative or already established gene expression stress markers (Metallothionein, Superoxide dismutase, Catalase, Glutathione S transferase, Glutathione peroxidase, Cytochrome c oxidase, the multixenobiotic resistance P-gp1, and heat shock proteins HSP70 and HSP90) were analyzed by quantitative Real-Time PCR in adults and pediveliger larvae after exposure to metals (Hg, Cu, Cd). A defined pattern of coordinated responses to metal exposure and, presumably, to oxidative stress was observed in gills and digestive gland from adults. A similar, albeit partial response was observed in larvae, indicating an early development of stress-related gene responses in zebra mussel. The tools developed in this study may be useful both for future control strategies and for the use of zebra mussel as sentinel species in water courses with stable populations.  相似文献   
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