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111.
Antarctic krill, Euphausia superba, hatched from eggs and maintained for four years, were sampled periodically for age-pigment analysis. Extractable pigments from the eye and eyestalk ganglia were quantified using fluorescence intensity and standardised against protein. Three peak fluorescence intensities were detected at wavelengths of excitation 280 nm, emission 625 nm (pigment 1); excitation 355 nm, emission 510 nm (pigment 2); and excitation 463 nm, emission 620 nm (pigment 3). There was a positive correlation between the quantity of pigments 1 and 3 and the age of Antarctic krill. A model was developed to predict age from pigment 3 and to compare it with other age proxies (carapace length and eyeball diameter). The quantity of pigment 3 was the best predictor of age. The pigment method can discriminate between similar sized krill aged 12 and 36 months. Age pigments provide an improved tool for age estimation in Antarctic krill, particularly if used in conjunction with other demographic information.  相似文献   
112.
The responsiveness of adult beech and spruce trees to chronic O(3) stress was studied at a free-air O(3) exposure experiment in Freising/Germany. Over three growing seasons, gas exchange characteristics, biochemical parameters, macroscopic O(3) injury and the phenology of leaf organs were investigated, along with assessments of branch and stem growth as indications of tree performance. To assess response pattern to chronic O(3) stress in adult forest trees, we introduce a new evaluation approach, which provides a comprehensive, readily accomplishable overview across several tree-internal scaling levels, different canopy regions and growing seasons. This new approach, based on a three-grade colour coding, combines statistical analysis and the proficient ability of the "human eye" in pattern recognition.  相似文献   
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The current article maps perfluoroalkyl acids (PFAAs) contamination in the largest Science Park of Taiwan. The occurrence of ten target PFAAs in the effluent of an industrial wastewater treatment plant (IWWTP), its receiving rivers, rainwater, sediment, and the muscles and livers of fish was investigated. All target PFAAs were found in effluent of IWWTP, in which perfluorooctane sulfonate (PFOS) (6,930 ng/L), perfluorohexyl sulfonate (PFHxS) (2,662 ng/L) and perfluorooctanoic acid (PFOA) (3,298 ng/L) were the major constituents. Concentrations of PFBS and PFOS in the IWWTP downstream areas have exceeded safe concentration levels of avian and aquatic life, indicating a potential risk to wildlife in those areas. In sediment samples, predominant contaminants were PFOS (1.5–78 ng/g), PFOA (0.5–5.6 ng/g), and perfluorododecanoic acid (PFDoA) (nd–5.4 ng/g). In biological tissue samples, concentrations as high as 28,933 ng/g of PFOS were detected in tilapia and catfish liver samples. A positive correlation for log (C sediment/C water) and log (C tissue/C water) was found. The concentration and proportion (percentage of all PFAAs) of PFOS found in biotissue samples from the Keya River (which receives industrial wastewater) were found to be much greater (200 times) than those of samples from the Keelung River (which receives mainly domestic wastewater). These findings suggest that the receiving aquatic environments and, in turn, the human food chain can be significantly influenced by industrial discharges.  相似文献   
116.
The characteristics of natural soils often vary from those of artificial soil (e.g. OECD), which may lead to substantial differences in the bioavailability of test substances. The aim of this investigation was to characterise the development of phenanthrene catabolism in both natural and artificial soils with varying total organic carbon (TOC) content after 1, 14, 42 and 84 d soil-phenanthrene contact time. Indigenous catabolic activity was measured via the addition of 14C-phenanthrene using the respirometric soil slurry assay. Notably, the lag phases, fastest rates and total extents of 14C-phenanthrene degradation were relatively comparable in soils with similar TOC content after 1 d contact time. However, natural soils generally exhibited significantly shorter lag phases, faster rates and higher extents of mineralisation, than their artificial counterparts after 42 and 84 d contact time. Such findings suggest that the extrapolation of results from artificial soils to real/natural soils may not be straightforward.  相似文献   
117.
The loss and degradation of nature can lead to hopelessness and despair, which may undermine engagement in conservation actions. Emerging movements, such as that behind the organization Conservation Optimism, aim to avert potential despair of those involved in conservation. Some argue that fostering positive states, such as hope or optimism, can motivate engagement and action; however, others question whether fostering hope or optimism may inadvertently undermine perceived gravity of conservation challenges. We examined this issue by quantifying dispositional hope and optimism with a representative sample of Australians (n = 4285) and assessing their relationship with indicators of conservation engagement. We used the Great Barrier Reef (GBR) in Australia as a case study. We asked participants what they could do to help the GBR, then classified their responses into 2 outcome variables: identifying climate actions (i.e., actions that tackle the main threat to the reef) and identifying plastic actions (i.e., actions that are popular among community members). We also quantified likelihood of performing these actions and appraisals of both threats and actions. One dimension of hope, hope pathways (defined by Snyder's hope theory as knowing different ways to act), was associated with greater capacity to identify climate-related behaviors (odds ratio [OR] = 1.44) and plastic reduction behaviors (OR = 1.22) and greater likelihood of adopting climate-related actions (β = 0.20). Optimism was associated with recognition of plastic reduction behaviors only (OR = 1.22). Neither hope nor optimism undermined appraisal of conservation threats. The effects of optimism were mediated by reduced action futility, and effects of hope pathways were mediated by stronger perceptions of threats to the reef (threat appraisal) and confidence in performing useful actions (coping appraisal). Our findings suggest that dispositional hope can strengthen, rather than undermine, appraisal of conservation challenges and solutions and thereby increase conservation engagement.  相似文献   
118.
This study is aimed at verifying the relevance of Ucides cordatus as a bioindicator of oil contamination and PAH bioavailability in mangrove sediments. For this, crabs and sediment cores were sampled from five mangroves, including an area suspected of contamination derived from an MF380 oil spillage, and analyzed for the 16 PAH in the USEPA priority list as well as for the five series of alkylated homologues. Concentrations in sediments varied from 35 microg kg-1 in the lower core layer of the control area to 33,000 microg kg-1 in the upper layer of the most contaminated area. Total PAH contents in crabs varied from 206 to 62,000 microg kg-1 and were closely correlated to that in sediments. In general, individual PAH profiles in both matrices were in good agreement. Phenanthrenes, however, were more predominant in crabs making up to 30-46% of the Total PAH. Accumulation factors found in the range of 0.7 to 35 were highly variable even after normalizing concentrations for organic carbon and lipid content. Survival in highly contaminated environment and reliable record of environmental contamination in the tissue provide evidence that U. cordatus is an excellent bioindicator for oil in mangroves.  相似文献   
119.
A detailed cradle‐to‐grave life‐cycle assessment (LCA) of an in situ thermal treatment remedy for a chlorinated‐solvent‐contaminated site was performed using process LCA. The major materials and activities necessary to install, operate, monitor, and deconstruct the remedy were included in the analysis. The analysis was based on an actual site remedy design and implementation to determine the potential environmental impacts, pinpoint major contributors to impacts, and identify opportunities for improvements during future implementation. The Electro‐Thermal Dynamic Stripping Process (ET‐DSP?) in situ thermal technology coupled with a dual‐phase extraction and treatment system was evaluated for the remediation of 4,400 yd3 of tetrachloroethene‐ and trichloroethene‐impacted soil, groundwater, and bedrock. The analysis was based on an actual site with an estimated source mass of 2,200 lbs of chlorinated solvents. The remedy was separated into four stages: remedy installation, remedy operation, monitoring, and remedy deconstruction. Environmental impacts were assessed using Sima Pro software, the ecoinvent database, and the ReCiPe midpoint and endpoint methods. The operation stage of the remedy dominated the environmental impacts across all categories due to the large amount of electricity required by the thermal treatment technology. Alternate sources of electricity could significantly reduce the environmental impacts of the remedy across all impact categories. Other large impacts were observed in the installation stage resulting from the large amount of diesel fuel, steel, activated carbon, and asphalt materials required to implement the technology. These impacts suggest where opportunities for footprint reductions can be found through best management practices such as increased materials reuse, increased recycled‐content materials use, and clean fuels and emission control technologies. Smaller impacts were observed in the monitoring and deconstruction stages. Normalized results show the largest environmental burdens to fossil depletion, human toxicity, particulate matter formation, and climate‐change categories resulting from activities associated with mining of fossil fuels for use in electricity production. In situ thermal treatment can reliably remediate contaminated source areas with contaminants located in low‐permeability zones, providing complete destruction of contaminants in a short amount of time, quick return of the site to productive use, and minimized quantities of hazardous materials stored in landfills for future generations to remediate. However, this remediation strategy can also result in significant emissions over a short period of time. It is difficult to quantify the overall value of short‐term cleanups with intense treatment emissions against longer‐term cleanups with lower treatment emissions because of the environmental, social, and economic trade‐offs that need to be considered and understood. LCA is a robust, quantitative tool to help inform stakeholder discussions related to the remedy selection process, trade‐off considerations, and environmental footprint‐reduction opportunities, and to complement a broader toolbox for the evaluation of sustainable remediation strategies. © 2012 Wiley Periodicals, Inc.  相似文献   
120.
ABSTRACT

This article considers the format and cultural politics of the hugely successful UK television program Top Gear (BBC 2002–2015). It analyzes how—through its presenting team—it constructed an informal address predicated around anti-authoritarian or contrarian banter and protest masculinity. Regular targets for Top Gear presenter’s protest—curtailed by broadcast guidelines in terms of gender and ethnicity—are deflected onto the “soft” targets of government legislation on environmental issues or various forms of regulation “red tape. Repeated references to speed cameras, central London congestion charges and “excessive” signage are all anti-authoritarian, libertarian discourses delivered through a comedic form of performance address. Thus, the BBC’s primary response to complaints made about this program was to defend the program’s political views as being part of the humor. The article draws on critical discourse analysis and conversation analysis to consider how the program licensed a particular form of engagement that helped it to deflect criticisms, and considers the limits to such discursive positioning. We conclude by examining the controversies that finally led, in 2015, to the removal of the main presenter, Jeremy Clarkson, and the ending of this version of the program through the departure of the team to an on-demand online television service.  相似文献   
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