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Population genetic structure of the thorny skate (Amblyraja radiata) was surveyed in >300 individuals sampled from Newfoundland, Iceland, Norway, the Kattegat and the central North Sea. A 290-bp fragment of the mt cytochrome-b gene was first screened by SSCP. Sequences of SSCP haplotypes revealed 34 haplotypes, 14 of which were unique to Iceland, 3 to Newfoundland, 1 to Norway and 3 to the Kattegat. The global F ST was weak but significant. Removal of the two Kattegat locations, which were the most differentiated, resulted in no significant genetic differentiation. Haplotype diversity was high and evenly distributed across the entire Atlantic (h = 0.8) with the exception of the North Sea (h = 0.48). Statistical parsimony revealed a star-like genealogy with a central widespread haplotype. A subsequent nested clade analysis led to the inference of contiguous expansion with evidence for long distance dispersal between Newfoundland and Iceland. Historical demographic analysis showed that thorny skates have undergone exponential population expansion that started between 1.1 million and 690,000 years ago; and that the Last Glacial Maximum apparently had little effect. These results strongly differ from those of a parallel study of the thornback ray (Raja clavata) in which clear structure and former refugial areas could be identified. Although both species have similar life history traits and overlapping ranges, the continental shelf edge apparently does not present a barrier to migration in A. radiata, as it does for R. clavata.  相似文献   
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Paul Foley 《环境政策》2017,26(5):915-937
To contribute to the literature on transnational sustainability governance hybrids, a new fisheries certification program in Iceland that was originally developed as an alternative to the non-governmental Marine Stewardship Council is examined. While this new program appears on the surface to constitute a purely nationalistic reaction against external non-state authority, the new governance institution is also non-governmental and incorporates international norms and institutions. To explain this new governance hybrid, Robert Cox’s International Political Economy approach to production and power is engaged. This approach theorizes the co-constitution of the social forces of production, state–society complexes and global governance. It is argued that the Icelandic case is not entirely localized or unique; it is part of a broader movement in which social forces of production respond to new market-oriented transnational sustainability governance institutions by developing territorially embedded but transnationally legitimate alternatives.  相似文献   
3.
The Environmental Impact Assessment (EIA) project instigated in connection with the near-closure of the large fjord-like lagoon Gilsfjörður in sub-arctic western Iceland with a road is described and discussed. Three phases were involved: a survey of pre-impact conditions of areas possibly affected as well as control areas, predictions of impacts of the road, and assessment of impacts up to 5–6 years after completion of the project. Emphasis was placed on birds and benthic flora and fauna. Although several predictions were upheld, others were not. The most unexpected changes were the elimination of kelp forest and some associated fauna inside the road as well as from large areas outside it. Feeding areas of the knot (Calidris canutus) and female eiders (Somateria mollissima) with ducklings also changed in unexpected ways. Unforeseen changes can partly be traced to inadequate knowledge of communities and their functioning in the area. The ecological requirements of many species involved, e.g. with respect to salinity, were imperfectly known. The predictions of engineers on the effects of the project on physical factors were not as accurate or detailed as desired. Some critical predictions of the engineers failed to make an impact on the ecologists, who then failed to predict some major changes in the biota, such as the disappearance of kelp forest outside the road. This study highlights some problems probably shared by many EIAs: (a) the near impossibility of finding suitable control areas, (b) the lack of ecological understanding of even common species, and possibly (c) inadequate communication between engineers and ecologists.  相似文献   
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The transfer of peat organic matter (OM) from tidal pools of upper littoral to downstream rocky shores and its potential incorporation into marine biota were investigated using the stable isotope approach. Samplings were carried out in September 2004 in two SW Icelandic sites (Osar and Hvassahraun), where we selected (1) areas with shores where grass gently declined towards rocks and, on reaching the sea line, formed small tidal peat pools and (2) areas where grass and rocky shores were not contiguous, rather the grass lower limits were several hundreds of meters back from the shore. In both grass and no grass areas, in the intertidal zone, all benthic organisms and all potential OM sources were sampled. Dominant macroalgae were Ascophyllum nodosum ([Linnaeus] Le Jolis) and Fucus vesiculosus Linnaeus. In grass sites, organisms partially reflected the isotopic composition of peat OM, while in no grass sites, peat represented only a negligible amount of available OM, or its signal was totally absent from the environment. Intertidal organisms could rely on peat both directly by suspension feeding, grazing or scavenging and indirectly by predation (crabs) on low level consumers (barnacles).  相似文献   
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