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161.
Many environmental contaminants known today are semivolatile organic compounds (SOC) and are present in the atmosphere. Airborne SOC are taken up and enriched by the epicuticular wax that covers leaves of higher plants. The purpose of the present work was to use pine needles 1) to map the distribution of airborne SOC in Europe, 2) to identify source regions, and 3) to identify hitherto unknown anthropogenic and/or natural substances. Some of the results were a confirmation of a suspected release of DDT in the former East Germany, high levels of pentachlorophenol were noted in Scandinavia, hexachlorocyclohexanes were higher in southern than in northern Europe, whereas PCB and hexachlorbenzene were rather evenly distributed throughout Europe. Elemental sulphur was identified as a previously unknown natural substance in higher plants.  相似文献   
162.
There is inadequate morphological nomenclature and definition of organ pathology when using wild fish in biomonitoring of environmental pollution. The aim of this investigation was to provide a guide that assesses histology of Shorthorn (Myoxocephalus scorpius) and Fourhorn (Myoxocephalus quadricornis) sculpins obtained from a study using these two fish species as bioindicator organisms to evaluate environmental impact attributed to a dumpsite located in East Greenland. Specific histopathological lesions were quantified on the basis of Bernet et al. and all lesions were photomicrographed, evaluated, and placed into specific categories of five reaction patterns. These were circulatory disturbances, regressive changes, progressive alterations, inflammation, and tumors based on anatomical location, type, and severity. This method is postulated to enable an objective assessment of the histological integrity of fish gills and liver; thus, making it possible to compare sculpin pathology and reaction patterns at different locations. Data suggest that this updated histological guide might be used for identification and quantification of histological lesions when applying sculpins in biomonitoring programs in Greenland and other Arctic regions.  相似文献   
163.
Abstract

For many years, the sculpin has been utilized as a sentinel monitoring species for anthropogenic impacts on the marine environment. To further develop its potential as a screening model body burden of several trace elements, including cadmium (Cd), copper (Cu), mercury (Hg), lead (Pb) and selenium (Se), were investigated. In addition, histopathology in shorthorn sculpins (Myoxocephalus scorpius; n?=?20) and fourhorn sculpins (Myoxocephalus quadricornis; n?=?10) were examined at three sites around the Scoresby Sound settlement in Central East Greenland. Fourhorn sculpins caught at the most distant site from the settlement, contained significantly higher hepatic Cu and Cd concentrations as well as significantly elevated gill Pb levels compared to the shorthorn sculpins collected at two other sites closer to the settlement. Histological examinations showed that fish with significantly higher concentrations of hepatic Cd and Se exhibited greater nuclear alterations, interstitial hyperplasia/hypertrophy, interstitial mononuclear infiltrations and granulomas. Further, fish with higher Cd and Cu gill tissue levels displayed a significantly higher number of cytoplasmic alterations and lamellar epithelium lifting, hypertrophic and hyperplastic epithelium along with mucus cell hyperplasia. While the presence of liver lesions were not species or sex-specific, the presence of gill lesions decreased in the order female fourhorn sculpins?>?female shorthorn sculpins?>?male fourhorn sculpins?>?male shorthorn sculpins. Hepatic Hg concentrations exceeded known lowest observable effect doses (LOED) for fish (0.1–0.5?μg g?1 ww) in 27% of fish, while liver Cd residues in 80% exceeded LOED (0.42–1.8?μg g?1 ww). Based upon these results, data suggest that using the sculpin as a valuable sentinel fish species histopathology may serve as a reliable tool for assessing marine ecosystem exposure to trace metals. However, confounding physiological and ecological factors also need to be considered.  相似文献   
164.
The purpose of the study was to investigate, whether the coastal grey dune vegetation at Anholt, Denmark, is limited by nitrogen or phosphorus. The island Anholt (22,37 km2) is situated in the centre of Kattegat A two factor fertilization experiment with nitrogen as NH4NO3 (N-addition) and phosphorus as KH2PO4 (P-addition) was carried out in the coastal grey dune vegetation of Anholt. The N-addition corresponded to 40 kg N ha?1 year?1 and the P-addition to 7 kg P ha?1 year?1 The experiment included N-, P-, N + P-addition and control. Lichens (genera: mainly Cladonia, Stereocaulon, Cetraria, Hypogymnia) and bryophytes (genera: Polytrichum, Racomitrium) cover most of the surface. Only two plant species, Corynephorus canescens and Empetrum nigrum, constitute nearly all vascular plant cover and biomass of this calcium poor coastal heath community. Corynephorus and Empetrum increased their cover significantly following N and N + P addition. No effect was observed by P addition alone. N limitation of this coastal heath vegetation remote from agricultural and industrial activities was evident. The effect on the plant species of the single application was short-lived. After two-three years of enhanced cover, the Corynephorus and Empetrum cover had returned to their level before the experiment. The lichen vegetation, however, changed more permanently, and after 12 years the subplots with N + P addition was dominated by rich growth of Cladina and Cetraria species. The results are discussed in relation to anthropogenic nitrogen deposition and conservation of this high priority ecosystem.  相似文献   
165.
166.
Environmental Economics and Policy Studies - In this paper, we investigate the economically optimal regulation of aquaculture production. The time between releasing and harvesting fish (rotation...  相似文献   
167.
Much evidence demonstrates the adverse effects of lead ammunition on wildlife, their habitats and human health, and confirms that the use of such ammunition has no place within sustainable hunting. We identify the provisions that define sustainable hunting according to European law and international treaties, together with their guidance documents. We accept the substantial evidence for lead’s actual and potential effects on wildlife, habitats and health as persuasive and assess how these effects relate to stated provisions for sustainability and hunting. We evaluate how continued use of lead ammunition negatively affects international efforts to halt loss of biodiversity, sustain wildlife populations and conserve their habitats. We highlight the indiscriminate and avoidable health and welfare impacts for large numbers of exposed wild animals as ethically unsustainable. In societal terms, continued use of lead ammunition undermines public perceptions of hunting. Given the existence of acceptable, non-toxic alternatives for lead ammunition, we conclude that hunting with lead ammunition cannot be justified under established principles of public/international policy and is not sustainable. Changing from lead ammunition to non-toxic alternatives will bring significant nature conservation and human health gains, and from the hunter’s perspective will enhance societal acceptance of hunting. Change will create opportunities for improved constructive dialogue between hunting stakeholders and others engaged with enhancing biodiversity and nature conservation objectives.  相似文献   
168.
The use of the lipophilic persistent organic pollutants (POPs) including polychlorinated biphenyls (PCBs) and several organochlorine pesticides (OCPs) has been prohibited for more than 30 years. In this study, we present the temporal trends of the lipophilic POP serum concentrations in Danish nulliparous pregnant women between 2011 and 2013. We randomly selected 197 pregnant women (gestational age 11–13) from the Aarhus Birth Cohort. The concentrations of the lipophilic POPs in the serum samples were analyzed using gas chromatography. The concentrations were corrected for total serum lipids. The statistical analysis was performed by regression analysis with adjustment for age, BMI, gestational age at blood draw, and smoking status. The serum concentrations of PCB 118, 138, 153, 156, 170, 180, 187, and hexachlorobenzen, trans-nonachlor, β-hexachlorocyclohexane (β-HCH), and p,p’-dichlorodiphenyldichloroethylene were lower in 2013 than in 2011. However, the oxychlordane concentration was lowest in 2011. The serum levels of most lipophilic POPs followed downward trends during the study period, which was expected, as these compounds has been banned for many years. The upward trend of oxychlordane was unexpected and presumably a chance finding.  相似文献   
169.
In order to understand the role of wild bees in both social and ecological systems, we conducted a quantitative and qualitative review of publications dealing with wild bees and the benefits they provide in social contexts. We classified publications according to several attributes such as services and benefits derived from wild bees, types of bee–human interactions, recipients of direct benefits, social contexts where wild bees are found, and sources of changes to the bee–human system. We found that most of the services and benefits from wild bees are related to food, medicine, and pollination. We also found that wild bees directly provide benefits to communities to a greater extent than individuals. In the social contexts where they are found, wild bees occupy a central role. Several drivers of change affect bee–human systems, ranging from environmental to political drivers. These are the areas where we recommend making interventions for conserving the bee-human system.  相似文献   
170.
In streams, chemicals such as 17β-estradiol (E2) are likely to occur in pulses. We investigated uptake and biomarker responses in juvenile brown trout (Salmo trutta) of 3- or 6-h pulses of concentrations up to 370 ng E2 L−1. Uptake by the fish was estimated from disappearance of E2 from tank water. A single 6-h pulse of 370 ng E2 L−1 increased the plasma vitellogenin concentration, liver Erα- and vitellogenin-mRNA. Exposure to 150-160 ng E2 L−1 for 6 h increased vitellogenin in one experiment but not in another. Two 6-h pulses had a larger effect one pulse. Brown trout in the size range 24-74 g took up E2 linearly with time and exposure concentration with a concentration ratio rate of 20.2 h−1. In conclusion, the threshold for induction of estrogenic effects in juvenile brown trout at short term pulse exposure appears to be in the range 150-200 ng E2 L−1.  相似文献   
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