排序方式: 共有27条查询结果,搜索用时 15 毫秒
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James H. Barrett David Orton Cluny Johnstone Jennifer Harland Wim Van Neer Anton Ervynck Callum Roberts Alison Locker Colin Amundsen Inge Bødker Enghoff Sheila Hamilton-Dyer Dirk Heinrich Anne Karin Hufthammer Andrew K.G. Jones Leif Jonsson Daniel Makowiecki Peter Pope Tamsin C. O’Connell Tessa de Roo Michael Richards 《Journal of archaeological science》2011
Archaeological fish bones reveal increases in marine fish utilisation in Northern and Western Europe beginning in the 10th and 11th centuries AD. We use stable isotope signatures from 300 archaeological cod (Gadus morhua) bones to determine whether this sea fishing revolution resulted from increased local fishing or the introduction of preserved fish transported from distant waters such as Arctic Norway, Iceland and/or the Northern Isles of Scotland (Orkney and Shetland). Results from 12 settlements in England and Flanders (Belgium) indicate that catches were initially local. Between the 9th and 12th centuries most bones represented fish from the southern North Sea. Conversely, by the 13th to 14th centuries demand was increasingly met through long distance transport – signalling the onset of the globalisation of commercial fisheries and suggesting that cities such as London quickly outgrew the capacity of local fish supplies. 相似文献
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Heinrich Helmer 《Standort - Zeitschrift für angewandte Geographie》2007,21(1):87-90
Die Wasserrahmenrichtlinie (WRRL) wird im Vergleich zur FFH- und zur Vogelschutzrichtlinie, deren Anforderungen etwa acht
Prozent der Landesfl?che von Nordrhein-Westfalen (NRW) betreffen, mit aufzustellenden Bewirtschaftungspl?nen fl?chendeckend
ganze Flusseinzugsgebiete erfassen und damit in ihren Auswirkungen für die Landwirtschaft alles Bisherige weit in den Schatten
stellen. Insofern hat sich die Landwirtschaft recht frühzeitig in den Umsetzungsprozess der EU-WRRL aktiv eingebracht – angefangen
von der Bestandsaufnahme über das Monitoring bis zu den jetzt anlaufenden Ma?nahmenprogrammen. 相似文献
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We present a reconstruction of the three‐dimensional (3D) geometry and gold grade distribution of shear zone‐hosted, Au‐mineralized, quartz–tourmaline veins of the Sigma deposit (Abitibi belt). Host shears and veins form a network of anastomosing, steeply dipping structures associated with smaller subhorizontal extensional veins. Our reconstruction has been carried out using the exceptionally large geological database of the mine. From this database, we extracted the geometric position, thickness and gold grades of geometrically best‐defined steep veins contained in a representative subvolume of the deposit. These data allowed the 3D representation of 53 veins, which have been constructed by fitting surfaces through the geometrical data and by contouring thickness and gold grade. The geometry of the network is mainly characterized by: (i) a few large segmented veins, with sinuous and helicoidal shape, and typical vertical dimension of >100 m; (ii) a large number of smaller vertical veins, some of which splay off the steep veins with high dip angles; (iii) subhorizontal extension veins (joints) located at, or close to, the tips of steep veins. The absolute thickness of the vertically short veins is the same as that of the large veins, suggesting that they formed simultaneously, but only a few of them interconnect to form vertically continuous bodies. Patchy, vertically elongated zones of high dilation are present in the large veins, and are poorly correlated with Au‐rich zones. They presumably represent former high‐permeability zones of the network. The highest gold grades occur at the interconnections between the large veins and small splays or subhorizontal joints. This indicates the important role of vein interconnection for fluid flow and gold precipitation within the network. Combining the calculation of the volume of the network with the estimation of tourmaline abundance in the veins, we calculate that 2.1 × 106 m3 of tourmaline and 3.2 × 106 m3 of quartz precipitated during Au deposition. 相似文献
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James Barrett Cluny Johnstone Jennifer Harland Wim Van Neer Anton Ervynck Daniel Makowiecki Dirk Heinrich Anne Karin Hufthammer Inge Bødker Enghoff Colin Amundsen Jørgen Schou Christiansen Andrew K.G. Jones Alison Locker Sheila Hamilton-Dyer Leif Jonsson Lembi Lõugas Callum Roberts Michael Richards 《Journal of archaeological science》2008
This paper explores the potential of stable isotope analysis to identify the approximate region of catch of cod by analysing bones from medieval settlements in northern and western Europe. It measures the δ13C and δ15N values of cod bone collagen from medieval control samples collected from sites around Arctic Norway, the North Sea, the Kattegat and the Baltic Sea. These data were considered likely to differ by region due to, for example, variation in the length of the food chain, water temperature and salinity. We find that geographical structuring is indeed evident, making it possible to identify bones from cod caught in distant waters. These results provide a new methodology for studying the growth of long-range trade in dried cod and the related expansion of fishing effort—important aspects of the development of commercialisation in medieval Europe. As a first test of the method, we analyse three collections of cod bones tentatively interpreted as imported dried fish based on a priori zooarchaeological criteria. The results tentatively suggest that cod were being transported or traded over very long distances since the end of the first millennium AD. 相似文献
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