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41.
A number of investigations have been undertaken by the New South Wales Water Resources Commission to determine the regional and compound effects of large scale extractive industries on the stability of the Hunter River, New South Wales. Sedimentologic studies of bed material suggest that the Hunter River upstream of Denman has an armoured gravel bed that is immobile during regulated releases from Glenbawn Dam but is disrupted by moderate but less than bankfull flows. Annual bedloadyields have been computed by the bedload rating-flow duration technique for five river gauging stations. Approximate sand and gravel budgets for selected reaches of the Hunter River demonstrate that the present annual extraction rate from temporary sediment storages within the channel greatly exceeds the transport rate upstream of Denman and is approximately equal to the transport rate downstream of Denman. River degradation is imminent if extractive industries continue operating in the channel of the Hunter River 相似文献
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ABSTRACT This paper develops a general multimarket hedonic model appropriate for a national, interregional study of wages, housing prices, and location-specific amenities. The model encompasses the effects of interregional location, intraurban location, and city size. Typically, hedonic studies focus on a single market such as labor or housing and ignore interactions implicit in a more global compensation mechanism. Examination of the comparative statics of our model indicates that single-market differentials are partial prices and are unreliable measures of amenity values in an interregional context. Unbiased amenity values are estimated for a comprehensive set of amenities using data on housing prices for 34,414 households and wages for 46,004 workers from the 1980 Census of Population and Housing. Statistically significant differences in housing prices and wages are found due to amenities. 相似文献
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James Anquandah 《African Archaeological Review》1987,5(1):171-180
An Iron Age complex which flourished around the fifteenth to the seventeenth century AD is currently under investigation in Komaland, northern Ghana. The complex is known chiefly from its numerous burial sites characterized by stone circles and earth mound superstructures, and containing human and animal burials, domestic pottery, milling stones, metal implements and cast figures, together with ubiquitous and distinctive terracotta sculptures. This paper discusses the findings from the first season's excavation and their significance in West African archaeology.
Résumé Des recherches actuellement en cours portent sur un complexe de l'Age du Fer, qui a prospéré entre le 15e et le 17e siècle après J.C., en Komaland, au nord du Ghana. Le complexe est connu surtout par ses nombreux sépultures caractérisées par des cercles de pierres, avec comme superstructures des tumulus de terre où se trouvent des inhumations de humains et d'animaux, de la céramique domestique, des molettes, des outils en métal, et des figures coulées, avec des sculptures en terre cuite ubiquistes et distinctives. Cet article présente des résultats de la première saison de fouilles, et discute de leur signification dans l'archéologie de l'Afrique Occidentale.相似文献
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There is a growing tendency to conceive of hunter-gatherer adaptations as points on a yardstick, with foragers at one end and collectors on the other. Such a view limits our perspective and may trap anthropologists into seeing these categories as steps in an evolutionary progression. It is more productive to think of human adaptation as an N-dimensional space, with individual cases occurring at the intersections of the various dimensions. When this viewpoint is taken, it becomes clear that a search for a single dimension in archaeological data that can be used to characterize all prehistoric adaptations is unlikely to be fruitful. This paper explores the multidimensionality of hunter-gatherer adaptive behavior and reviews those archaeological manifestations that are empirically or logically linked with various dimensions of three components of adaptation: mobility, predation, and technology. Those manifestations with the greatest potential for characterizing prehistoric hunter-gatherer adaptive strategies are identified as measures of mobility type, frequency, stability, scheduling, demography, and range; predation mode, breadth, and scheduling; and the time budgeting and storage dimensions of technology. A subset of these measures is evaluated by comparing assemblages from the late prehistoric Columbia Plateau with expectations derived from ethnographies written on the same local area. 相似文献
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P. P. BETANCOURT 《Archaeometry》1987,29(1):45-49
The beginning of the Late Bronze Age in the Aegean has usually been thought to coincide with the start of the Eighteenth Dynasty in Egypt, and radiocarbon dates (which consistently suggest an earlier chronology) have been rejected by Aegean specialists because they do not agree with this view. Evidence from pottery is used to re-examine the links between the Aegean and Egypt, with the conclusion that the Aegean Late Bronze Age began during the Hyksos period. 相似文献