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1.
Liesbeth Weijs Sara Losada Krishna Das Laurence Roosens Peter J.H. Reijnders Javier F. Santos Hugo Neels Ronny Blust Adrian Covaci 《Environment international》2009,35(6):893-899
Harbour seals and harbour porpoises are top predator species from the North Sea, have long life spans and hence, are known to accumulate high levels of anthropogenic contaminants. To gain knowledge about the behaviour of naturally-produced compounds in these marine mammals, the biomagnification of naturally-produced methoxylated polybrominated diphenyl ethers (MeO-PBDEs) was assessed. The biomagnification of MeO-PBDEs (2′-MeO-BDE 68 and 6-MeO-BDE 47) was lower in harbour seals (all biomagnification factors (BMFs) < 1) compared to the same age–gender groups of the harbour porpoises (all BMFs > 1). This may indicate a better metabolic breakdown of MeO-PBDEs in harbour seals, as was previously suggested for polybrominated diphenyl ethers (PBDEs). In both predators, 6-MeO-BDE 47 had the highest concentrations (range: 45–483 ng/g lw and 2–38 ng/g lw for harbour porpoises and seals, respectively) compared to 2′-MeO-BDE 68 (range: 2–28 ng/g lw and 1–6 ng/g lw for harbour porpoises and seals, respectively). In general, the highest concentrations were found in juveniles, suggesting an increased biotransformation capacity with age or the influence of dilution by growth for both species. Here we show that naturally-produced brominated organic compounds can biomagnify and accumulate in North Sea top predators, although to a lesser extent than anthropogenic lipophilic contaminants, such as polychlorinated biphenyls (PCBs) or PBDEs. 相似文献
2.
The relation between Acid Volatile Sulfides (AVS) and metal accumulation in aquatic invertebrates: Implications of feeding behavior and ecology 总被引:3,自引:0,他引:3
Maarten De Jonge Ronny Blust Lieven Bervoets 《Environmental pollution (Barking, Essex : 1987)》2010,158(5):1381-1391
The present study evaluates the relationship between Acid Volatile Sulfides (AVS) and metal accumulation in invertebrates with different feeding behavior and ecological preferences. Natural sediments, pore water and surface water, together with benthic and epibenthic invertebrates were sampled at 28 Flemish lowland rivers. Different metals as well as metal binding sediment characteristics including AVS were measured and multiple regression was used to study their relationship with accumulated metals in the invertebrates taxa.Bioaccumulation in the benthic taxa was primarily influenced by total metal concentrations in the sediment. Regarding the epibenthic taxa metal accumulation was mostly explained by the more bioavailable metal fractions in both the sediment and the water. AVS concentrations were generally better correlated with metal accumulation in the epibenthic invertebrates, rather than with the benthic taxa. Our results indicated that the relation between AVS and metal accumulation in aquatic invertebrates is highly dependent on feeding behavior and ecology. 相似文献
3.
Why do blue-eyed men prefer women with the same eye color? 总被引:1,自引:0,他引:1
The human eye color blue reflects a simple, predictable, and reliable genetic mechanism of inheritance. Blue-eyed individuals represent a unique condition, as in their case there is always direct concordance between the genotype and phenotype. On the other hand, heterozygous brown-eyed individuals carry an allele that is not concordant with the observed eye color. Hence, eye color can provide a highly visible and salient cue to the child’s heredity. If men choose women with characteristics that promote the assurance of paternity, then blue-eyed men should prefer and feel more attracted towards women with blue eyes. To test these predictions, close-up photos of young women and adult men with either blue or brown eyes were rated for their attractiveness by young women and men observers with either blue or brown eyes (N=88). The eye color in the photographs of each model was manipulated so that a same face would be shown with either the natural eye color (e.g., blue) or with the other color (e.g., brown). Both blue-eyed and brown-eyed female participants showed no difference in their attractiveness ratings for male models of either eye color. Similarly, brown-eyed men showed no preference for either blue-eyed or brown-eyed female models. However, blue-eyed men rated as more attractive the blue-eyed women than the brown-eyed ones. We interpret the latter preference in terms of specific mate selective choice of blue-eyed men, reflecting strategies for reducing paternity uncertainty. In a second study, a group of young adults (N=443) of both sexes and different eye colors (blue, brown, and green) were asked to report the eye and hair color of their romantic partners. Their responses indicated the presence of assortative mating by eye color as well as, to a less degree, for hair color. Most importantly, blue-eyed male respondents were the group with the largest proportion of partners of same eye color. These findings 1) indicate that blue-eyed men do prefer women with the same eye color and 2) specifically suggest the presence of a male adaptation for the detection of extra-pair paternity based on eye color, as a phenotypically based assurance of paternity (i.e., when the father’s and offspring’s phenotypes match) as well as a defense against cuckoldry (i.e., when the phenotypes do not match).Electronic supplementary material Supplementary material is available in the online version of this article at and is accesseble for authorized users. 相似文献
4.
Habitat type-based bioaccumulation and risk assessment of metal and As contamination in earthworms, beetles and woodlice 总被引:1,自引:0,他引:1
Frouke Vermeulen Nico W. Van den Brink Helga D'Hav Valentine K. Mubiana Ronny Blust Lieven Bervoets Wim De Coen 《Environmental pollution (Barking, Essex : 1987)》2009,157(11):3098-3105
The present study investigated the contribution of environmental factors to the accumulation of As, Cd, Cu, Pb and Zn in earthworms, beetles and woodlice, and framed within an exposure assessment of the European hedgehog. Soil and invertebrate samples were collected in three distinct habitat types. Results showed habitat-specific differences in soil and invertebrate metal concentrations and bioaccumulation factors when normalized to soil metal concentration. Further multiple regression analysis showed residual variability (habitat differences) in bioaccumulation that could not be fully explained by differences in soil metal contamination, pH or organic carbon (OC). Therefore, the study demonstrated that in bioaccumulation studies involving terrestrial invertebrates or in risk assessment of metals, it is not sufficient to differentiate habitat types on general soil characteristics such as pH and/or OC alone. Furthermore, simple generic soil risk assessments for Cd and Cu showed that risk characterization was more accurate when performed in a habitat-specific way. 相似文献
5.
D'Havé H Scheirs J Mubiana VK Verhagen R Blust R De Coen W 《Environmental pollution (Barking, Essex : 1987)》2006,142(3):438-448
The role of hair and spines of the European hedgehog as non-destructive monitoring tools of metal (Ag, Al, Cd, Co, Cr, Cu, Fe, Ni, Pb, Zn) and As pollution in terrestrial ecosystems was investigated. Our results showed that mean pollution levels of a random sample of hedgehogs in Flanders are low to moderate. Yet, individual hedgehogs may be at risk for metal toxicity. Tissue distribution analyses (hair, spines, liver, kidney, muscle and fat tissue) indicated that metals and As may reach considerable concentrations in external tissues, such as hair and spines. Positive relationships were observed between concentrations in hair and those in liver, kidney and muscle for Al, Co, Cr, Cu, and Pb (0.43 < r < 0.85). Spine concentrations were positively related to liver, kidney and muscle concentrations for Cd, Co, Cr, Cu and Pb (0.37 < r < 0.62). Hair Ag, As, Fe and Zn and spine Ag, Al, As and Fe were related to metal concentrations in one or two of the investigated internal tissues (0.31 < r < 0.45). The regression models presented here may be used to predict metal and As concentrations in internal tissues of hedgehogs when concentrations in hair or spines are available. The present study demonstrated the possibility of using hair and spines for non-destructive monitoring of metal and As pollution in hedgehogs. 相似文献
6.
Dauwe T Janssens E Bervoets L Blust R Eens M 《Environmental pollution (Barking, Essex : 1987)》2004,131(3):373-380
Metal concentrations (Ag, As, Cd, Cu, Hg, Ni, Pb, Zn) were determined in the feathers and excreta of nestling great tits (Parus major), in their main invertebrate prey (Lepidoptera larvae) and in vegetation samples, all collected from four sites along a pollution gradient. Metal contamination in vegetation samples increased significantly towards the pollution source. The Ag, As, Hg, Ni and Pb concentrations in food samples were significantly higher at the site closest to the pollution source compared to the other three sites. Great tit nestlings from the site closest to the pollution source had significantly higher concentrations of Ag, As, Hg and Pb in their excreta than did nestlings at the other three sites. For five metals (Ag, As, Cu, Ni and Pb), we found concentrations in caterpillars to be significantly positively correlated with vegetation samples. We also found clear significant positive correlations between excreta and caterpillars for Ag, As, Hg and Pb and between feathers and caterpillars for As and Pb. Our data suggest that excreta are a good monitor for the presence and concentrations of non-essential metals in the food and the environment of passerine birds. 相似文献
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8.
Christina G.L. Nerstad Rosalind Searle Matej Černe Anders Dysvik Miha Škerlavaj Ronny Scherer 《组织行为杂志》2018,39(4):429-447
Interpersonal trust is associated with a range of adaptive outcomes, including knowledge sharing. However, to date, our knowledge of antecedents and consequences of employees feeling trusted by supervisors in organizations remains limited. On the basis of a multisource, multiwave field study among 956 employees from 5 Norwegian organizations, we examined the predictive roles of perceived mastery climate and employee felt trust for employees' knowledge sharing. Drawing on the achievement goal theory, we develop and test a model to demonstrate that when employees perceive a mastery climate, they are more likely to feel trusted by their supervisors at both the individual and group levels. Moreover, the relationship between employees' perceptions of a mastery climate and supervisor‐rated knowledge sharing is mediated by perceptions of being trusted by the supervisor. Theoretical contributions and practical implications of our findings are discussed. 相似文献
9.
Modeling habitat suitability for moose in coastal northern Sweden: empirical vs process-oriented approaches 总被引:1,自引:0,他引:1
Habitat models may provide viable tools for co-management of large ungulates and forest resources, yet their applicability has not been comprehensively evaluated in managed forest. We examined 2 inherently different approaches to model the relative winter habitat suitability for moose (Alces alces) in the coastal area of northern Sweden. An empirical approach based on GPS positions of 15 female moose was used to scrutinize the assumptions and functional mechanisms of a process-oriented, conceptual approach, based on published material on the species' preferences for habitat components related to food and cover. For both model approaches habitat was described using estimates of forest-stand characteristics based on satellite imagery. The empirical model also included variables relating to topographic properties of the landscape as well as distances to landscape features. The output from both models was a habitat suitability index (HSI) score, enabling the models to be compared with each other. The models showed different results, highlighting the need to include the spatially explicit distribution of environmental variables in future conceptual, process-oriented models. 相似文献
10.
Fish community responses to metal pollution 总被引:1,自引:0,他引:1
Bervoets L Knaepkens G Eens M Blust R 《Environmental pollution (Barking, Essex : 1987)》2005,138(2):338-349
The effect of metal pollution on fish communities was assessed at 47 sites, including a Cd and Zn gradient. Fish community structure was assessed by applying diversity indices, index of biotic integrity and the abundance/biomass comparison method (ABC-index). To relate the community responses to metal pollution, toxic unit values for dissolved metals (TU(w)) and for metals in fish liver (TU(t)) were calculated. If all sites were considered only a good relationship was found between the IBI and the TU(w), with 56% of the variation in IBI being described. Within the pollution gradient (sites 1--12) the described variation increased up to 85%. Relating the community structure to TU(t), the described variation in IBI further increased to 87%. Our results indicate that besides water quality other factors influenced diversity and ABC-index. The IBI proved a suitable index for the assessment of metal pollution, provided that other water quality characteristics meet the water quality criteria. 相似文献