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A sharp increase in 2005 of pp'DDT and its metabolites was observed in mussels and fish from lakes Como and Iseo, the main glacier-fed southern Alpine lakes. DDTs in zebra mussels (Dreissena polymorpha) were more than 150 times higher than levels in 2003, and concentrations in pelagic fish (0.12 mgkg(-1) w.w.) exceeded the Italian safety threshold for human consumption (0.05 mgkg(-1) w.w.). The histological examination of the ovaries revealed many mussels with oocyte degeneration throughout the studied period. Prior to being banned in Italy in 1978, DDT was used in large amounts for fruit-tree treatment from the 1950s to 1970s in valleys just below the glaciers. Since glacier volume was increasing at that time and then continuously retreated, meltwater should be the main cause of the pollution peak recently observed in biota of downstream lakes. PCBs did not peak in biota tissues to a comparable extent probably because local sources were not as important as for DDTs.  相似文献   
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From a life history perspective, glucocorticoids secreted by the neuroendocrine system, integrating different sources of stress through an adaptive feedback mechanism, may have important consequences on individual fitness. Although stress responses have been the object of several investigations, few studies have explored the role of proximate mechanisms responsible for the potential trade-offs between physiological stress and life history traits integrating social and environmental stressors. In 2011 and 2012, we collected data on faecal cortisol metabolites (FCM) in a marked male population of Alpine chamois, within the Gran Paradiso National Park (Italy). Using a model selection approach we analysed the effect of potential etho-ecological stressors such as age, social status (territorial vs. non-territorial males), minimum temperature, snow depth and precipitation on FCM variation. To correctly interpret environmentally and socially induced stress responses, we conducted model selections over multiple temporal scales defined a priori: year, cold months, spring, warm months, mating season. Over the year, FCM levels showed a negative relationship with minimum temperature, but altogether, climatic stressors had negligible effects on glucocorticoid secretion, possibly owing to good adaptations of chamois to severe weather conditions. Age was negatively related to FCM during the rut, possibly due to greater experience of older males in agonistic contests. Social status was an important determinant of FCM excretion: while both the ‘stress of subordination’ and the ‘stress of domination’ hypotheses received some support in spring and during the mating season, respectively, previous data suggest that only the latter may have detrimental fitness consequences on male chamois.  相似文献   
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Marbofloxacin (MAR) and Enrofloxacin (ENR), two largely employed veterinary Fluoroquinolones (FQs), were found to be present at the micrograms per kilogram level in agricultural soils of South Lombardy (Italy) several months after manuring. Distribution coefficients (Kd) from sorption experiments indicated a strong binding to the soil. Soil samples fortified with environmentally significant FQs amounts (0.5 mg kg−1) were exposed to solar light that promoted extensive degradation (80%) of both drugs in 60-150 h. Thus, photochemistry could be considered a significant depollution path in the soil, although it was two orders of magnitudes slower than in aqueous solution and a fraction of the drug (ca. 20%) remained unaffected. For MAR the photoprocess was the same as in solution, and involved cleavage of the tetrahydrooxadiazine ring. On the contrary, with ENR only some of the photoproducts determined in water (those arising from a stepwise oxidation of the piperazine side chain) were observed. Substitution of the 6-fluoro by a hydroxyl group and reduction did not occur in the soil, supporting the previous contention that such processes required polar solvation of FQs. Consistently with this rationalization, the irradiation of thin layers of solid drugs led to essentially the same products distribution as in the soil. From the environmental point of view it is important to notice that photodegradation mainly affects the side-chains, while the fluoroquinolone ring, to which the biological effect is associated, is conserved up to the later stages of the degradation.  相似文献   
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Recently, much attention has been devoted to urban air pollution because epidemiological studies have reported health impacts related to particulate matter (PM). PM10 and PM2.5 were collected during different seasons in Torino, a northern Italian city, and were characterised by inorganic chemical species (secondary particulates and bio-available iron). The biological effects of aqueous and organic solvent PM extracts on human epithelial lung A549 were evaluated, and the effects on cell proliferation and lactate dehydrogenase (LDH) release were assayed. The average PM10 concentration during the sampling period was 47.9?±?18.0 μg/m3; the secondary particles accounted for 49 %?±?9 % of the PM10 total mass, and the bio-available iron concentration was 0.067?±?0.045 μg/m3. The PM2.5/PM10 ratio in Torino ranged from 0.47 to 0.90 and was higher in cold months than in warm months. The PM10 and PM2.5 extracts inhibited cell proliferation and induced LDH release in a dose-dependent manner with a seasonal trend. The PM10 extract had a stronger effect on LDH release, whereas the PM2.5 extract more strongly inhibited cell proliferation. No significant differences were observed in the effects induced by the two extracts, and no significant correlations were found between the biological effects and the PM components evaluated in this study, thus emphasising the importance of the entire mixture in inducing a cytotoxic response.  相似文献   
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Human activities are accelerating global biodiversity change and have resulted in severely threatened ecosystem services. A large proportion of terrestrial biodiversity is harbored by soil, but soil biodiversity has been omitted from many global biodiversity assessments and conservation actions, and understanding of global patterns of soil biodiversity remains limited. In particular, the extent to which hotspots and coldspots of aboveground and soil biodiversity overlap is not clear. We examined global patterns of these overlaps by mapping indices of aboveground (mammals, birds, amphibians, vascular plants) and soil (bacteria, fungi, macrofauna) biodiversity that we created using previously published data on species richness. Areas of mismatch between aboveground and soil biodiversity covered 27% of Earth's terrestrial surface. The temperate broadleaf and mixed forests biome had the highest proportion of grid cells with high aboveground biodiversity but low soil biodiversity, whereas the boreal and tundra biomes had intermediate soil biodiversity but low aboveground biodiversity. While more data on soil biodiversity are needed, both to cover geographic gaps and to include additional taxa, our results suggest that protecting aboveground biodiversity may not sufficiently reduce threats to soil biodiversity. Given the functional importance of soil biodiversity and the role of soils in human well-being, soil biodiversity should be considered further in policy agendas and conservation actions by adapting management practices to sustain soil biodiversity and considering soil biodiversity when designing protected areas.  相似文献   
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Processes such as economic polarization, social disparities and the asymmetric distribution of natural capital are becoming progressively more interlinked in developed countries and may reflect the uneven decline of the ‘centre-periphery’ model. The assessment of regional disparities and spatial heterogeneity in socioeconomic phenomena is a key issue in regional studies and takes advantage of the use of multi-domain frameworks and decision support systems. We performed an exploratory analysis of 133 indicators assessing seven thematic domains (demography/settlements, labour market, economic structure, quality of life, agriculture/rural development, landscape/water, environment/soil resources) with the aim of investigating regional disparities in Italy in the light of territorial changes driven by urbanization, industrial decentralization, agricultural intensification and land abandonment. The results of our study indicate that latitude, elevation and urban gradients have determined a complex spatial pattern in both socioeconomic and environmental variables in Italy. The proposed approach provides an overall assessment of the intensity of territorial disparities on a regional scale for each thematic domain, and of intra-region spatial heterogeneity for each indicator, representing a decision-making tool for policies targeting a sustainable and spatially balanced development.  相似文献   
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Bivalve mollusks as filter-feeders concentrate in their digestive tissue microorganisms likely present in the harvesting water, thus becoming risky food especially if consumed raw or poorly cooked. To eliminate bacteria and viruses eventually accumulated, they must undergo a depuration process which efficacy on viruses is on debate. To better clarify the worth of the depuration process on virus elimination from mussels, in this study we investigated rotavirus kinetics of accumulation and depuration in Mytilus galloprovincialis experimentally contaminated. Depuration process was monitored for 9 days and virus residual presence and infectivity were evaluated by real time quantitative polymerase chain reaction, cell culture and electron microscopy at days 1, 2, 3, 5, 7, 9 of depuration. Variables like presence of ozone and of microalgae feeding were also analyzed as possible depuration enhancers. Results showed a two-phase virus removal kinetic with a high decrease in the first 24 h of depuration and 5 days necessary to completely remove rotavirus.  相似文献   
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