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51.
A palaeoecological approach was undertaken to investigate the last 400 years of change in vegetation, fire, nutrient mobility, lake productivity and erosion associated with Aboriginal and European land-use practices in a forested environment in eastern Victoria. Melaleuca ericifolia scrub, although present prior to European settlement, has expanded around Lake Curlip in the last 200 years, primarily due to the action of fire on a forest already weakened by drought. A fern understorey has declined in extent and a more open aspect has developed in the forest. Fire has been a major component of vegetation dynamics in the historical period. Erosion rates were comparatively low and associated with fire during prehistoric times, but after European settlement its increase is more closely related to land clearance and flooding than fire. The response of vegetation to both anthropogenic and natural influences changed during the historical period. Although fire is an integral part of vegetation change, it is not an over-riding effect at Lake Curlip. Drain construction in the swamp has reduced the impact that any accumulation of pasture improvement chemicals may have had on eutrophication of the lake.  相似文献   
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Glass finds from the first Bulgarian capital, Pliska, have been analysed by instrumental neutron activation analysis. The analytical data, together with previous results from analysis of glass samples from the second Bulgarian capital, Preslav, were subjected to cluster and discriminant analysis. The local origin of part of the analysed samples was proven and some conclusions about the technology of production were possible.  相似文献   
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This article briefly examines the consequences of the European presence on the Gold Coast, focusing on archaeological, ethnographic, and historical data from the African settlement of Elmina, Ghana. Documentary sources indicate that there was extensive change in sociopolitical institutions, economic relations, and other aspects of Gold Coast society in the centuries following the advent of European trade in the late fifteenth century. Archaeological survey and excavation of some 30 structures at Elmina similarly indicates a great deal of change in construction technology and material culture during the post-European contact period. However, examination of artefact patterning and associations indicates that in certain respects there was little change in terms of people's shared world view and belief systems. This picture can be contrasted with data from sites in other areas which may have experienced a great deal of culture change during the post-European contact period.
Résumé Cet article examine brièvement les conséquences de la présence européenne sur la Côte de l'Or, se penchant plus particulièrement sur les données archéologiques, ethnographiques et historiques du site d'Elmina au Ghana. Les sources documentaries indiquent qu'un changement de grande envergure affectant les institutions socio-politiques, les relations économiques et d'autres aspects de la société de la Côte de l'Or pris place durant les siècles suivant l'arrivée du commerce européen à la fin du quinzième siècle. Un survey archéologique et les fouilles d'environ 30 structures à Elmina, indiquent aussi qu'un changement étendu des techniques de construction et de la culture matérielle s'effectue après la période de contact européen. Toutefois, l'étude de la distribution et des associations des objets, indique que le système de croyance et l'idée du monde partagée par cette société furent peu affectés.Cette image peut être comparée avec les données obtenues sur d'autres sites ayant fait l'expérience d'un changement culturel important pendant la période postérieure aux contacts européens.
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Cryptocrystalline silicates from the Chadron Formation were widely used by prehistoric human groups in the Great Plains of North America. There are two documented quarry areas: Flattop Butte in Colorado and the White River Badlands of South Dakota. Cryptocrystalline silicates from these sources are visually indistinguishable, making it difficult to determine the sources of artefacts found at archaeological sites. In this investigation, neutron activation analysis is used to distinguish the two sources. This technique also identifies lithic material from the Clovis-age Eckles site in Kansas as being from Flattop Butte.  相似文献   
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This paper is concerned with the products of a number of Neolithic quarries in highland Britain. It investigates the claim that the scale of axe distribution was partly the result of social factors which resulted in these artefacts gaining an added value in areas remote from their sources. One case study considers the sequence of production in Cumbria, in relation to the tensile strength of the rock quarried in different parts of the region. It shows that these considerations had only a limited influence over the choice of stone source and the scale on which it was worked. A second study compares the tensile strength of the main raw materials used for making non-flint axes with the extent to which these sources were actually exploited. Again there is only a limited relationship between the two, suggesting that social factors may indeed have been important.  相似文献   
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