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991.
992.
993.
Taxonomic, anatomical, and spatio-temporal variations in the stable carbon and nitrogen isotopic compositions of plants from an African savanna 总被引:5,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
994.
THE ORIENTATION OF ROMAN CAMPS AND FORTS 总被引:1,自引:1,他引:0
A. RICHARDSON 《Oxford Journal of Archaeology》2005,24(4):415-426
Summary. The angles of orientation of 67 Roman camps were determined from their published plans. There was a marked tendency for them to be aligned close to the cardinal points but they were offset from those points by only 28 of a possible 45 angles and of these six occurred in 29 camps, probably because they were set out by making right-angled triangles whose non-hypotenuse sides were in whole number ratios. Twenty-seven forts on the British frontier walls were similarly orientated by only 12 angles, one of which occurred six times. The apparent accuracy of the layouts suggested that the directions of the meridian and latitude were first carefully determined. The use of a limited number of offset angles was probably due to a religious regard for celestial geometry. 相似文献
995.
E. Gliozzo D. D’Aco I. Memmi Turbanti A. Galli M. Martini E. Sibilia 《Archaeological and Anthropological Sciences》2009,1(2):77-85
Twenty-one samples of likely Roman, likely Islamic and unknown common ware from the archaeological site of Thamusida (Rabat, Morocco) were analysed in order to anchor selected types of pottery to a limited time span and, possibly, to a production
area and technology. Analytical techniques were thermoluminescence, optical microscopy, scanning electron microscopy and X-ray
fluorescence. The results arising from this research are definitely useful for the study of the site of Thamusida as well as for all researchers involved in archaeological and archaeometrical research in Morocco. Chronologies proposed
on a typological base have been denied twice: a likely Islamic cup dates back to the second century a.d.; vice versa, a stewpot, framed into the Roman period, resulted to be an eighth century a.d. production. Moreover, the identification of an eighteenth century ceramic production is of outstanding importance, as it
characterises a completely unknown production. Regarding the production area, four samples of both Roman and Islamic periods
have been recognised as local productions of Thamusida. 相似文献
996.
A. CRISTINA DE LA VEGA‐LEINERT SUSANNE STOLL‐KLEEMANN TIM O'RIORDAN 《Geographical Research》2009,47(4):351-361
This paper makes the case for advancing sustainability science partnerships (SSPs) both within universities and through innovative means of integrating universities with external public‐private and civil sectors. It links the basic principles of sustainable development with an emerging science of cooperative learning that connects researchers to a wide range of partners. SSPs are specifically designed to be transformational through becoming active agents for societal change. Universities play a special role here because they can act both as communication networks and as laboratories for developing the capability to design and manage SSPs in the creative transition to sustainability. It is gratifying to note that these ideas are beginning to emerge in a number of universities, with European examples being highlighted in this paper. Further steps towards introducing full‐blooded SSPs across the university spectrum are suggested. 相似文献
997.
As evidence concerning human mobility during the transition to agriculture in central Europe, we present the results of strontium isotope analysis of human skeletons from the Neolithic village of Vaihingen, Germany. We find significantly more ‘non‐local’87Sr/86Sr values from humans buried in a Neolithic ditch surrounding Vaihingen than from those buried within the settlement. These results fit with previous studies showing a correlation between burial circumstances and strontium isotope signatures from LBK cemeteries of southwestern Germany ( Price et al. 2001 ; Bentley et al. 2002 ). A pilot study of Neolithic animal teeth from Vaihingen suggests that either ‘local’87Sr/86Sr signatures were more variable than the analysed human bones suggest, or that these domestic animals themselves were mobile, perhaps ranged by mobile pastoralists. 相似文献
998.
Fragments of late medieval highly decorated Falke‐group stoneware have been found in excavations all over central and northern Europe. The distribution of the finds points to an origin in Saxony, but the exact centre of production is still unknown. Therefore, a set of samples has been analysed with Neutron Activation and the data compared with Saxon reference groups. The results point to production in a single workshop. The data can be clearly distinguished from all reference groups in our databank. However, the most similar group is that of Zittau, Saxony. Also, one sherd, which is typologically very similar to the Falke group, and which was made in Zittau, suggests that production was based there. 相似文献
999.
J. Buxeda I Garrigs R. E. Jones V. Kilikoglou S. T. Levi Y. Maniatis J. Mitchell L. Vagnetti K. A. Wardle S. Andreou 《Archaeometry》2003,45(2):263-284
The study of technology transfer in pottery production to the periphery of the Mycenaean world has been addressed by considering two different areas, southern Italy and central Macedonia. Technological features such as ceramic paste, decoration and firing have been determined for different ceramic groups established according to provenance criteria. The studies of technology and provenance have been performed following an archaeometric approach, using neutron activation analysis, petrographic analysis, X‐ray diffraction and scanning electron microscopy. The results have revealed the existence of two different models. On the one hand, southern Italy seems to exhibit a more organized pottery production, which follows a Mycenaean‐like technology, while in central Macedonia production is probably more varied, being based in part on the technology of the local tradition. 相似文献
1000.
Previously published data on the chemical compositions and microstructures of copper‐ and cobalt‐blue frit, glass and faience from the New Kingdom site of Amarna in Egypt ( Shortland 2000 ) are summarized. The data are then used to infer the raw materials and processes employed in the production of these vitreous materials. The results suggest that crushed quartz pebbles were the source of the quartz for all the materials, but that different sources of alkali, both natron and a range of plant ashes, were used in the production of each material. It seems probable that the cobalt‐rich alum colorant was pre‐treated before use by precipitating cobalt hydroxide from a solution of the alum by the addition of natron. It is further hypothesized that cobalt‐blue glass was produced by melting the cobalt‐blue frit together with additional plant ash and possibly quartz. Finally, it is suggested that, in glazing the cobalt‐blue Variant D faience first produced in the 18th Dynasty, the efflorescence or application method was selected according to object type. 相似文献