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991.
Abstract

Maps of Africa produced in the sixteenth century relied on Ptolemy for their representation of the unknown heart of the continent. However, another cartographic model, which challenged the classical authority in several respects, became available for the depiction of the African interior. This was the map attributed to Duarte Lopes (Odoardo Lopez) and published by Filippo Pigafetta in 1591. Since contemporary cartographers had no way of verifying which model presented the African interior most realistically, other facts must explain the pre‐eminence of one model over the other.  相似文献   
992.
“Crisis” in cultural policy is a widespread phenomenon, whose meaning can be exemplified in case of opera. The Berlin, Paris and London opera houses hit a crisis at the end of the twentieth century. At the core of these crises and the discussions surrounding them were funding problems – which were also a point of academic interest. But beyond that, opera seemed to be an arena of discourse where creeping conflicts in the political system and society were debated as fundamental crises of a most cherished cultural heritage. This paper examines how, in these cases, “crisis” proves to be a cultural phenomenon in itself, displaying a symbolic and functional character rather than being defined by references to specific matters and qualities.  相似文献   
993.
There has been relatively little comparative research undertaken on sub‐national cultural policy. This article aims to contribute to the development of sub‐national comparative studies by assessing the utility of national cultural policy approaches for comparative research at the sub‐national level in Canada. Drawing on studies of national cultural policy, the authors develop three main approaches to cultural policy and administration – the French, British and hybrid approaches – and explore their applicability to the origin and evolution of cultural policy and administration in the Canadian provinces of Québec and Ontario. This exploratory research suggests there is room for optimism in drawing on national‐level experiences to undertake sub‐national comparative cultural policy research, particularly for comparisons over broad time periods. The study also suggests that it will be important in subsequent research to further elaborate the models for present‐day comparative analysis and to refine and adapt them to reflect specificities at the provincial level of analysis.  相似文献   
994.
Many sixteenth- to eighteenth-century shipwrecks have been found after land reclamation in parts of the former Zuiderzee, one of the busiest waterways in Dutch history. After the land fell dry, some shipwrecks were excavated, destroyed, reburied, or covered with sand or clay. In the late 1970s a method was developed to mitigate degradation processes of some of the wrecks remaining in good condition by wrapping them in plastic foil. The idea was that the plastic would prevent evaporation and lateral subsurface flow. Wet conditions prevent decomposing of wood by especially soft rot fungi. Oxygen will be rapidly depleted by decomposition of organic matter.

Recent monitoring of wrapped shipwrecks has shown that this method of preventing rot worked exceptionally well. We adapted wrapping using new technology nowadays applied for sealing tunnels and landfills. We will present the implementation requirements, materials and new adapted method for wrapping shipwrecks.  相似文献   
995.
Canton Thurgau (approximately 1000 km2) is situated in the north-east of Switzerland. Its diverse landscape is notable for its hills, the Thur Valley, and Lake Constance. The Archaeology Department of Canton Thurgau is responsible for its archaeology. The archaeological map is quite complete and has over one thousand sites, ranging from the Palaeolithic to post-medieval periods. Particularly remarkable are the prehistoric lakeside dwellings (among them, four UNESCO World Heritage Sites) and the Roman sites, some of which have extraordinarily good conditions for preservation. The vicus Tasgetium (Eschenz) has produced one of the largest collections of Roman wooden objects and features found anywhere in the world. The Archaeology Department of Canton Thurgau conducts field surveys, excavations and scientific research. Its collections and archive are also of great importance. A major goal is to preserve the numerous sites of the canton in situ. In sensitive shore areas, where erosion (wave action, shipping etc.) threatens the exposed prehistoric cultural layers of the pile dwellings, measures are being taken to cover the areas and keep destruction at bay. These interventions are accompanied by monitoring. But numerous Roman and medieval ruins have also been restored according to the latest standards and thus prevented from gradual destruction. Thanks to zoning plans and a close working relationship with the local authorities, timely intervention can take place when sites are threatened. The results of the archaeological research are conveyed to the public and professional circles through the Museum for Archaeology and by way of popular and subject-specific publications.  相似文献   
996.
Preservation in situ and the monitoring of archaeological sites have become important themes since the acceptance and implementation of the Valletta Treaty. In the last few decades, our knowledge of degradation processes has increased manyfold, and a range of techniques have been tested and applied for use in both assessment and monitoring. Despite these successes, all is not well. First, we have little notion of the speed of the decay processes involved. This makes it difficult to distinguish between acute and protracted degradation. Apart from that, many assessments and subsequent monitoring projects rely (too?) heavily on complex and costly specialist technology. For any future preservation — in situ — projects low-tech observations together with best estimates of decay rates and archaeological site information should be combined to make an accurate assessment of the effects of decay on the archaeological record. Monitoring for preservation purposes is only appropriate if (1) decay processes occur within a relevant and measurable time scale, and (2) if mitigating actions can be taken or preservation ex situ can be performed (i.e. a rescue excavation) if significant degradation takes place.  相似文献   
997.
Monitoring of the archaeological deposits at the World Heritage Site Bryggen in Bergen has been ongoing since 2001. In latter years a large-scale project of mitigation works has been carried out, resulting in the creation of a water-management system aimed at raising groundwater-levels and increasing soil moisture content in areas with poor preservation conditions. Oxygen is a key parameter in the decay of archaeological material in the unsaturated zone, and the monitoring at Bryggen includes in situ monitoring of oxygen concentrations and comparison to soil moisture content, temperature, groundwater-level, precipitation and soil reactivity. This is used to document where and when decay takes place and to estimate “how wet is wet enough” in order to reduce the oxygen diffusion and the decay rate to an acceptable level. The results show that even small changes in the soil moisture can have a large impact on the oxygen dynamics in the ground.  相似文献   
998.
Abstract

Archaeological, biological, and geochemical investigations of soil sample series from a section and five boreholes have been studied to evaluate the state of preservation at the time of investigation and the preservation conditions of urban archaeological deposits from medieval Oslo, Norway. Focus has been put on the most fragile deposits in the unsaturated and fluctuation zones. Even with limited investigations, it is possible to assess the archaeological conservation state and the preservation conditions. Further work should focus on interpreting measured results and on mitigation strategies.  相似文献   
999.
Abstract

Underwater Cultural Heritage (UCH) as an outstanding division of the cultural heritage of humanity appears to be crucial and complicated when more general issues regarding preservation and conservation are raised. The essence of in situ preservation should be equally discussable for any kind of archaeological remains; on land or underwater.

There is a long history of different methods and concepts of intervention in a variety of sub-aquatic archaeological sites; from shipwrecks to submerged settlements. This paper will present an introduction to different techniques and theories of preservation and conservation of underwater cultural and archaeological sites since this kind of heritage has scientifically been explored and studied. A range of different preservation methodologies, from total or partial transference inland, to preservation underwater, will be compared; the advantages and disadvantages of each option will be highlighted. Different examples of international best practices will be illustrated. Different types of in situ conservation/protection will be explained and categorized. Furthermore, there will be a focus on the UNESCO Convention of 2001 on Conservation and Preservation of UCH, where the in situ conservation option has been recommended.

Moreover, the technical issue for preservation of UCH sites, either in situ or after displacement, will be explained. The implication of relocation for different sorts of sites and materials will be argued; for example, cases where some sites, such as shipwrecks, would more easily be displaced compared with submerged settlements, villages, or ports.

Finally, by stressing that the state of ‘being underwater’ makes many sites qualified to be regarded as UCH, the in situ preservation approach will prevail that this state is maintained.  相似文献   
1000.
Abstract

The site of Nydam Mose saw the beginning of systematic research into in situ preservation of waterlogged archaeological sites on land at the National Museum of Denmark. In the past fifteen years a generic approach to in situ preservation of archaeological sites has been developed based on this research. This article is primarily a review of this generic approach, summarizing the methods and results with particular reference to the published results from the investigations in Nydam Mose.  相似文献   
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