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91.
Tim H.E. Heaton Glynis Jones Paul Halstead Taxiarchis Tsipropoulos 《Journal of archaeological science》2009,36(10):2224-2233
Variations in the 13C/12C ratios of wheat grain at different spatial and temporal scales are examined by analysis of modern samples, including harvests of einkorn and durum wheat from Greece, and serve as a guide to interpreting data for Bronze Age grains from Assiros Toumba. The normal distribution and low variability of δ13C values of einkorn from 24 containers in the Assiros storerooms are consistent with pooling of local harvests, but less likely to represent the harvest of several years or include grain imported from further afield. Correlation between emmer and spelt δ13C values provides strong support for other evidence that these were grown together as a maslin crop. 13C discrimination (Δ) for the Bronze Age samples is estimated to be 2.5‰ larger than at present, and would be consistent with an intensive, horticultural regime of cereal cultivation, possibly involving some watering. 相似文献
92.
Karl W. Butzer 《Journal of Historical Geography》2009,35(4):776-777
93.
Karl J. Reinhard Sergio M. Chaves John G. Jones Alena M. Iñiguez 《Journal of archaeological science》2008
Molecular analysis of coprolites from Hinds Cave, Texas recovered chloroplast DNA sequences. The sequences were interpreted as evidence of diet. We analyzed 19 Hinds Cave coprolites to evaluate the potential sources of the chloroplast DNA (cpDNA) and compared our results to previous studies. This review shows that some cpDNA sequences could be from well-known prehistoric plants foods. Some other sequences could have come from ambient plant material in the guts of small animals eaten by humans in antiquity. Using pollen concentration analysis, we identify sources of ambient plant material which could have been inhaled or imbibed. It is even possible that cpDNA sequences are from proplastids within ambient pollen grains themselves. However, three sequence types cannot be explained as resulting from only dietary or ambient sources. We suggest instead that these might be from medicinal or hallucinogenic plants. We compared these three sequences to existing sequences in the GenBank. We found that these sequences are 100% matches for Rhamnus, Fouquieria, and Solanum. 相似文献
94.
This essay will examine, through a Kentucky case study, the process whereby states, county-level localities, and individuals undertook for themselves the responsibility for internal improvements, especially the construction of comprehensive road networks in the nineteenth century. Before the Kentucky legislature authorized state-funded road construction in the twentieth century, the state's best roads were a few toll turnpikes. Following other eastern states, Kentucky approved turnpike construction charters and subscribed to turnpike stock to underwrite construction. State statutes, based upon directives from trained engineers hired by the Board of Internal Improvement, required that turnpike construction follow complex procedures. A change in the state constitution in 1850 forced the state to withdraw from turnpike road investment and road construction oversight and finance devolved to counties and private investors. Local county road networks were largely the product of neighborhood turnpike companies chartered by the state. Primary documents record the local road-building process for a five-mile turnpike in a Bourbon County. With little direction or assistance from state engineers, the neighborhood residents, led by farmer John W. Jones, surveyed a route, arranged for right-of-way access through adjacent farms, hired Irish turnpike construction crews, built a tollhouse, and collected tolls. Formal state law and engineering directives became attenuated as amateur turnpike builders constructed a simplified version of the state's ideal road. 相似文献
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Rebecca A. Fraser Amy Bogaard Tim Heaton Michael Charles Glynis Jones Bent T. Christensen Paul Halstead Ines Merbach Paul R. Poulton Debbie Sparkes Amy K. Styring 《Journal of archaeological science》2011
This paper explores the impact of animal manure application on the δ15N values of a broad range of crops (cereals and pulses), under a range of manuring levels/regimes and at a series of locations extending from northwest Europe to the eastern Mediterranean. We included both agricultural field experiments and areas where ‘traditional’ farming is practised. Our aim is to ground-truth interpretation of δ15N values in archaeobotanical crop remains as evidence of past growing conditions and husbandry practices. The results confirm the potentially radical impact of manuring on δ15N values in cereals, depending on manuring level, but indicate only a slight effect on pulses, which can fix atmospheric nitrogen. The expected geographical trend towards greater δ15N with increasing climatic aridity is not apparent, probably because the growing conditions for crops are ‘buffered’ through crop management. Each of these observations has fundamental implications for archaeobotanical interpretation of δ15N values as evidence of land use practices and (together with analysis of bone collagen/tooth enamel in potential consumers) palaeodiet. 相似文献
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