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The measurement of stable carbon (δ13C) and nitrogen (δ15N) isotopes of caprine bone collagen from the Neolithic sites of Çatalhöyük and Aşıklı Höyük in south-central Anatolia have allowed examination of exploitation and herding practices of sheep and goats. The isotope values from protodomestic caprines at Aşıklı Höyük suggests that these animals were consuming very similar foods to each other and were all confined to the same or similar environments with no access to C4 plants. At Çatalhöyük, the results show how the caprine management strategy develops from the strategy seen at Aşıklı Höyük into a more varied practice at an early stage as the site grows with an increasing dietary contribution obtained from C4 plants. No change in diet is isotopically discernible at Aşıklı Höyük. Interestingly, no distinction could be made between the diets of sheep and goats at either site. Therefore, such studies are a useful method of examining the development of early herding or management strategies of caprines in the Near East.  相似文献   
3.
Human and domesticate animal bone collagen δ15N values in prehistory differ generally by 3‰ or more from Neolithic to post- Roman times in Northwest Europe, leading to an assumed dietary animal protein fraction of 60–80% using a standard interpretation of δ15N values. We examine the assumptions on which this model rests and the limitations of our knowledge in the analysis of δ15N values in archaeology. We have developed a set of models which, with small changes made in assumptions (on the order of 1‰), can produce substantially lower estimates of the dietary animal protein fraction for given δ15N values. We consider the implications of various dietary animal protein fractions on agricultural carrying capacities and human population densities in prehistory.  相似文献   
4.
用吸收采样法分析检测空气中二氧化氮时,亚硝酸根离子的显色反应直接关系到检测结果的灵敏度和检测下限。显色液的主要成分为重氮化试剂和偶合试剂。为了提高检测灵敏度和寻找优化的显色体系,本工作比较了对氨基苯磺酰胺和N-1-萘乙二胺盐酸盐组成的显色液在不同浓度比和不同酸性介质中(磷酸pH=1.5和1:1盐酸pH<0.5)对NO_2~-的显色情况。实验结果表明,当显色剂浓度适量,用磷酸为酸性介质(pH=1.5)时,短时间显色更快速灵敏。合适的显色液组成为:对氨基苯磺酰胺4g/L,N-1-萘乙二胺盐酸盐0.06g/L,磷酸28ml/L。本工作还比较了Salzman显色剂对同一标准系列亚硝酸根的测定结果,经线性回归分析得出:Salzman显色剂具有显色稳定等优点,但用于二氧化氮固体吸收剂的分析时,显色灵敏度偏低。  相似文献   
5.
We analyse the isotopic values (δ13C, δ15N) of the diet of pre-Columbian horticulturalist populations from tropical and subtropical areas of southeastern South America, belonging to the Guarani and Taquara archaeological units. The data indicate different trends in each one (T?=?4.21; P?=?0.0004), showing a mixed diet with maize consumption in the Guarani samples (δ13Cco?=??15.5?±?1.8‰; δ13Cap ?10.4?±?0.8‰) and a depleted one in the Taquara ones (δ13Cco ?18.2?±?1.7‰; δ13Cap ?11.9?±?0.9‰), with a significant internal dispersion in both populations. The first population has higher nitrogen values (δ15N 11.1?±?0.6‰) compared to the Taquara samples (δ15N 9.3?±?1‰), suggesting a more carnivorous diet. The recognition of these pre-Columbian mixed diets involves the identification of maize cultivation on the Atlantic side of the southernmost area of South America (Parana Delta, 34° SL). Through the analysis of δ18O we have identified two isotopic ecozones, the first along the Paraná River Valley, with an average value of δ18O ?3.7?±?0.5‰ (CV?=?13.5%; CI?=??3.83 / ?3.16), and the second one, located in the Planalto of southern Brazil (Araucaria Forest), with a mean value of δ18O ?1.5?±?0.3‰ (CV?=?16.5%; CI?=??1.69 / ?1.29). The isotopic data (δ13C, δ15N and δ18O) suggest human movements between these two ecozones.  相似文献   
6.
Changes in the stable carbon and nitrogen isotope ratios of modern bone samples heated to a variety of times and temperatures were used to determine the effect of heating on isotope ratios and the retention of organic matter in charred bones. For organic extracts produced by slow demineralization in weak acid, δ13C values were unchanged, while δ15N values increased by up to 5‰ and were primarily determined by heating temperature. Changes in the electron spin resonance (ESR) g-value of whole bone and organic extracts were also measured. For organic extracts from charred bones, the g-value was well-correlated with δ15N and temperature, suggesting that g-values could be used to estimate the charring temperature and original δ15N values of charred bones. Thus, g-values from demineralized extracts could be very useful in forensic investigations where it would important to reconstruct the thermal history of burned bones. Isotope ratios and g-values of demineralized extracts from four prehistoric components at three sites that produced cremated human bone were used to test whether the same approach can be applied to archaeological materials. While carbon isotope ratios of the prehistoric samples were similar to those of uncharred specimens, nitrogen isotope ratios were increased and the g-value corrections for nitrogen isotope ratios were not effective.  相似文献   
7.
Carbon and nitrogen stable isotope values were measured from bone collagen extracted from archaeological Nubian human (n = 54) and faunal (n = 61) populations from the site of Kerma, Sudan. Collagen suitable for isotopic analysis was extracted from 22 faunal and 48 human samples from the Eastern cemetery site, dated to the Middle Kerma (c. 2050–1750 BC) and Classic Kerma (c. 1750–1500 BC) periods respectively. The isotopic data indicate that the human dietary regimen included a mix of C3 and C4 plant-derived components, with a larger C4 component than previously reported in archaeological Egyptian Nile Valley populations. Elevated δ15N values are attributed to consumption of dietary resources from a 15N-enriched terrestrial ecosystem. The faunal isotope data also indicate the consumption of C3 and C4 plants. The large range of δ13C values measured in both the human and faunal samples supports previous work suggesting that a significant portion of the populations buried at Kerma may have originated elsewhere, further confirming the Nile Valley as a major corridor for population movement in the region.  相似文献   
8.
This further nitrogen isotopic study of Greenlandic Norse archaeological sites provides new evidence of the affect of past human activity on modern plant δ15N values. Grass samples were taken from a number of spatially defined features at four Norse farms and one site interpreted to be a seasonally occupied herding station (sæter). At the farms, un-naturally high δ15N values were found for plants from each sampled feature, including those from the likely infields and a churchyard. At the sæter no strong isotopic effect was expected and none was found. Comparing the data from the farms we found that the average plant δ15N values were similar for features that were functionally alike. We conclude from these observations, that the unusually high plant δ15N values reflect the strong conservation of the isotopic composition of the nitrogenous materials deposited in the past, and the magnitude of the values reflects the amount of this material admixed in the soil. The results confirm previous exploratory studies of this isotopic effect and further demonstrate its potential value as an archaeological tool.  相似文献   
9.
上海博物馆书画陈列馆环境监测与治理   总被引:3,自引:3,他引:0  
为了全面了解上海博物馆书画陈列馆陈列空气环境现状,对它进行了氮氧化物、二氧化硫、臭氧的检测,得出了氮氧化物是主要污染源。为此用氮氧化物自动测定仪、铜银试片法、On guard2000对此进行了较长时间的监测,在监测数据分析的基础上确定了治理方案,并已在实施。  相似文献   
10.
Here we report δ13C and δ15N measurements of serial sections of human deciduous and permanent tooth dentine from archaeological samples taken from the medieval village site of Wharram Percy, Yorkshire, UK. We found a pattern of enrichment, for both δ13C and δ15N, where the tooth crown was greater than the cervical part of the root, which in turn was greater than the apical portion of the root and the associated rib collagen values. This pattern reflects a decrease in the consumption of isotopically enriched breast milk and the introduction of less enriched weaning foods in the diet. The (mean±SD) difference between the deciduous second molar crowns and corresponding rib samples from the same individuals after 2 years of age was 1.2±0.4‰ for δ13C and 3.2±0.8‰ for δ15N. The δ15N values are as predicted, but as there were no C4plants at Wharram Percy, this 1.2‰ enrichment in δ13C represents clear evidence of a carbon trophic level effect in collagen from breastfeeding infants. Carbon and nitrogen results also show that the infant diet among those who died in infancy did not differ from those who survived into childhood. This study demonstrates the promise of using dentine serial sections to study the temporal relationships of breastfeeding, weaning, and dietary patterns of single individuals.  相似文献   
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