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81.
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   
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The aim of the paper is to summarise the present state of knowledge concerning bitumen trade in the Near East from the Palaeolithic (70,000 BP) to the Early Islamic period. During the Palaeolithic and Early Neolithic period, bitumen utilisation was mostly concentrated in settlements close to oil seeps. From the Ubaid 3 period, bitumen from the Mosul area became more important and was traded as far as the southern Persian Gulf. The Uruk period is a turning point for Mesopotamian history as settlements evolved into city‐states. These cities had a great need for raw materials, and this marks the beginning of large‐scale exploitation of Hit bitumen. This bitumen was traded at settlements along the Euphrates, where a large trade network was established. Hit bitumen entered the Persian Gulf at the turn of the second millennium (Dilmun period). Bitumen from Iraq (Mosul and Hit) became predominantly used in most settlements along the southern coast of the Gulf. During this period Iranian bitumen was also exported and this supply tended to increase, especially during the Partho‐Sasanian period. Dead Sea bitumen had its own exchange network, which was concentrated across present‐day Israel and Egypt where it was extensively used for mummification.  相似文献   
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ABSTRACT We use disaggregated data on Chilean plants, and the Chilean input–output table to examine the impact of agglomeration spillovers on total factor productivity (TFP). In common with previous studies, we find evidence for intraindustry spillovers, but none for general cross‐industry spillovers. This picture changes when we take vertical industry relations into account. There are important productivity spillovers from plants in upstream industries. Interestingly, a similar effect cannot be found from plants in downstream industries. The number of plants in these sectors has no effect on plant‐level TFP, just as the number of plants in other industries that are neither important upstream suppliers nor downstream customers also has no effect.  相似文献   
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The comparative study of sedimentary fabrics in relation to archaeological fabrics in various levels of the sites of Cova Gran de Santa Linya (Middle and Early Upper Palaeolithic) and the Roca dels Bous (Middle Palaeolithic) has made it possible to analyse the formation dynamics of the deposits and determine the extent of disturbance of the archaeological levels by natural processes. To achieve this, diagrams and two- and three-dimensional indices were calculated from the azimuth and dip angle of natural clasts and artefacts. The results indicate that the sedimentary levels were formed mainly by planar fabric shape gravitational processes (low depositional angles), which differ notably from the archaeological fabrics they contain, characterised by a greater degree of isotropy. This difference in the fabrics would reflect human activity and indicates that the archaeological levels both in Cova Gran and Roca dels Bous have not been subject to significant natural modifications, and are preserved in situ.  相似文献   
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This paper examines a recent dispute generated by the Queensland State Government proposal to build the Traveston Crossing Dam on the Mary River in southeast Queensland, Australia. It is particularly concerned with the ways in which interrelated issues of belonging, community identity, and social diversity were negotiated during the anti‐dam campaign. As an unusual alliance of farmers, environmentalists, urban retirees, some Aboriginal people and others, it takes a view of the anti‐Traveston Crossing Dam campaign as a fluid network of people and approaches the notion of community identity as the symbolic construction of similarity. Locally specific, the paper describes pertinent aspects of community politics in the context of rural socioeconomic change, and the mobilisation of heritage. With regard to local senses of belonging, it also discusses the involvement of Aboriginal people during the campaign. More broadly then, this paper attempts to make an ethnographic contribution to the study of environmental disputes and the politics of alliance in peri‐urban areas of settler‐descendant societies such as Australia.  相似文献   
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Recent research in Paleolithic archeology has stressed the importance of temporal issues in assemblage interpretation. Archeological assemblages are temporal constructs, formed by the addition of an unknown number of depositional events. This temporal dimension is also evident at the artifactual level, since single artifacts may undergo different events of modification and/or uses over time. The recycling of previously discarded blanks for tool production is one of the best examples of the temporal nature of artifacts. The aim of this paper is to evaluate the importance of recycling in a Late Upper Paleolithic site, examining a type of artifact – burned tools – that has up to now been little used to approach this issue. Our results suggest that recycling was probably a significant component of Upper Paleolithic provisioning behavior, with important implications in site formation processes and the typological variability of assemblages. The expedient or curated character of recycling is also discussed.  相似文献   
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