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61.
Oxygen is a key parameter in the degradation of archaeological material, but little is known of its dynamics in situ. In this study, 10 optical oxygen sensors placed in a 2 m deep test pit in the cultural deposits at Bryggen in Bergen have monitored oxygen concentrations every half hour for more than a year. It is shown that there is a significant spatial and temporal variation in the oxygen concentration, which is correlated to measured soil characteristics, precipitation, soil water content and degradation of organic material. In these deposits oxygen typically occurs when the air content of the soil exceeds 10–15% vol, while oxygen dissolved in infiltrating rainwater is of less importance for the supply of oxygen in the unsaturated zone. 相似文献
62.
Comparative policy studies face a number of methodological challenges where conceptualization of the object of comparison—policy output—is the most fundamental. On the basis of three common approaches of the study of policy output, we reconsider this widely applied concept and propose a refined measure as a function of both density (number of policy instruments) and intensity (content of policy instruments). We theoretically derive six policy‐intensity measures (objectives, scope, integration, budget, implementation, and monitoring), which are used for weighting national policy instruments on an Index of Climate Policy Activity. The article presents an empirical application of this measurement approach. Focusing on national climate policy instruments in the energy production sector in Austria, Germany, and the United Kingdom, we investigate changes in the countries' policy portfolios from 1998 to 2010. The article demonstrates that our Index of Climate Policy Activity provides a reliable and valid measurement for national policy output that can be applied for comparative analyses of policy output. 相似文献
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This paper studies the territorial effects of the LEADER approach in Southern Europe, by analysing the region of Andalusia (Spain). Our research has revealed that, in many cases, projects were concentrated in the most dynamic, most populated areas, with a well-established business network with the financial and organizational capacity required to access European funding. In these areas, the economic leadership of the most dynamic municipalities has been reinforced at the expense of more depressed areas with little social capital and few businesses. These programmes have not, therefore, helped to mitigate territorial imbalances. In a minority of rural areas, however, this trend was not observed, which shows that although territorial inequality is a widespread problem in the practice of neo-endogenous rural development, it does not affect all areas to the same degree. 相似文献
65.
José León García-Rodríguez Carlos Castilla-Gutiérrez 《European Planning Studies》2018,26(5):1028-1040
The defining element of island regions is their isolation, the separation of the islands from the mainland; there is an inherent notion of natural border. This condition has preserved ecosystems and protected against outside threats, stimulating ‘coevolution’ between man and the environment, a fundamental ingredient of sustainability. But insularity also means the evident added costs of access to markets which, together with territorial limits and the scarcity of basic resources, especially on small islands, hinders their socioeconomic development. These costs are even greater in the case of outlying islands, which suffer from a ‘double insularity’ in the form of both external and internal borders. For this reason, it is common for governments to establish various forms of support, from tax exemptions to the creation of permanent aid funds, like those implemented by the European Union for the outermost regions. This article discusses these aspects in the case of the Canary Islands, an example of a European outermost island region. The findings show that the support measures have not always been favourable for all the islands. 相似文献
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68.
Taxonomic, anatomical, and spatio-temporal variations in the stable carbon and nitrogen isotopic compositions of plants from an African savanna 总被引:4,自引:1,他引:4
Jacqui Codron Daryl Codron Julia A. Lee-Thorp Matt Sponheimer William J. Bond Darryl de Ruiter Rina Grant 《Journal of archaeological science》2005,32(12):1757-1772
Stable carbon (δ13C) and nitrogen (δ15N) isotope ratios are commonly used to reconstruct palaeodiets and palaeoenvironments. The method is based on our knowledge of isotopic patterns in plants, which are subject to taxonomic and environmental variability. While previous researchers have addressed isotopic variability amongst plants, no studies have looked extensively at a broad suite of taxa over multiple temporal scales from within the savanna biome so as to provide baseline data for palaeodietary and palaeoenvironmental studies. Here we document variations in the isotopic compositions of plants collected over two years from the Kruger National Park, South Africa, with respect to species and anatomical differences, and the influences of geological substrate and spatio-temporal shifts in climate. Results show that environmentally-induced carbon isotopic variations in plants within this region are generally smaller than 2‰, which is lower than what has been previously reported for plants compared across multiple habitat-types. These data suggest that δ13C differences of 2‰ or more (or 1‰ if the diet is predominantly C4) between animals from a given area reliably indicate real dietary differences. Plant δ15N values vary greatly between different microhabitats (by up to 4‰), responding to a range of environmental influences that may, in turn, significantly influence variation in animal δ15N values. 相似文献
69.
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
70.
Robert Van de Noort Brian Cumby Lucy Blue Anthony Harding Linda Hurcombe Tom Monrad Hansen Andy Wetherelt Jenny Wittamore Andy Wyke 《International Journal of Nautical Archaeology》2014,43(2):292-313
This paper reports on the construction of a full‐scale Bronze Age‐type sewn‐plank boat based on the Ferriby boats. The boat, which was named Morgawr, was constructed in the National Maritime Museum Cornwall in Falmouth, England, during 2012 and the first months of 2013, as part of a larger exhibition in the museum. This paper provides the background and context of the project, describes the process of building the craft, and reflects in particular on differences between Morgawr and the ‘hypothetical reconstruction of a complete sewn‐plank boat’ published in 1990 by Ted Wright and John Coates which formed the basis for this project. 相似文献