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1.
We investigated the contribution of freshwater resources to the diet of seven Late Mesolithic hunter-gatherers (ca. 5300–7000 BC) from Northern France and Luxembourg using stable isotope ratios. In addition to the carbon and nitrogen stable isotope ratios (δ13C, δ15N), we explored the potential of the sulphur isotopic ratios (δ34S) to detect and quantify the proportion of protein derived from aquatic foodstuff. In only two sites, animal remains from an associated settlement were available and subsequently examined to decipher the isotopic differential between terrestrial and freshwater resources. The quantification of their relative contribution was simulated using a Bayesian mixing model. The measurements revealed a significant overlap in δ13C values between freshwater and terrestrial resources and a large range of δ15N values for each food category. The δ34S values of the aquatic and terrestrial animals were clearly distinct at the settlement in the Seine valley, while the results on fish from Belgium demonstrated a possible overlap in δ34S values between freshwater and terrestrial resources. Local freshwater ecosystem likely contributed to ca. 30–40 % of the protein in the diet of the individuals found in the Seine settlement. Out of this context, the isotopic signature and thus contribution of the available aquatic foods was difficult to assess. Another potential source of dietary protein is wild boar. Depending on the local context, collagen δ34S values may contribute to better assessment of the relative contribution of freshwater and terrestrial resources.  相似文献   
2.
Research on complex systems has identified various aggregate relationships in phenomena that describe these systems. Travel length has been characterized by negative power distributions. Controversy, however, exists over whether mobility patterns can be modeled in terms of a simple power law (Lévy flight model) or that more complicated power laws (exponential power law, truncated Pareto) are required. This study concentrates on two issues: testing the validity of exponential power laws and truncated Pareto distributions in urban systems to describe aggregate mobility patterns, and examining differences in mobility patterns for different travel purposes. The article describes the results of an analysis of Global Positioning System (GPS) taxi trajectory data, collected in Guangzhou, China, to identify mobility patterns in the city. The least squares statistic is used to estimate the parameters of the distribution functions. Results suggest that a fusion of functions, based on an exponential power law and a truncated Pareto distribution, represents the travel time distribution best. Moreover, the findings of this study indicate different mobility patterns to exist for different travel purposes.  相似文献   
3.
Grasslands pose a particular problem for archaeological survey involving artifact assessment, as no material is plowed up to the surface. Although finds in molehills are often the only source of information available on sites with such low visibility, an archaeology of molehills has thus far been largely disregarded. Yet, by applying a low-cost and time-efficient methodology, both the potential and the pitfalls of molehill archaeology come to the forefront. At the medieval harbor site of Monnikerede, it was possible to assess material culture and to locate certain structural elements. However, when artifact densities were compared with the underlying geophysical anomalies, a more complex relationship appeared at the level of individual features.  相似文献   
4.
Archaeological practice within the European context of heritage management is facing huge challenges in ways of recording and reproduction of ex-situ preserved sites. As a consequence of the Valletta-treaty, numbers of archived images and drawings of excavated structures as prime sources of past human activity, are exponentially growing. Contrarily to portable remains however, their future study and revision is biased by the two-dimensional character of the recorded data, rendering difficult their future reconstruction for new study or public dissemination. A more realistic three-dimensional (3D) way of recording and archiving should be pursued. In this paper the possibilities for 3D registration of archaeological features are examined in a computer vision-based approach using the PhotoScan software package (Agisoft LCC). It proved to be a scientific and cost-effective improvement compared to traditional documentation methods. Advantages can be found in the high accuracy and straightforwardness of the methodology. The extraction of an orthophoto or a Digital Terrain Model from the 3D model makes it feasible to integrate detailed and accurate information into the digital archaeological excavation plan. The visual character of 3D surface modeling offers enhanced output-possibilities allowing a better documentation of in-situ structures for future research and a higher public participation and awareness for the archaeological heritage.  相似文献   
5.
The purpose of this paper is to demonstrate cross‐Channel exchange of calcareous sandstone‐type whetstones derived from the Weald (Sussex, UK) in the Roman period. The presence of this particular type of whetstone at several Roman sites on the Continent – more specifically, in Belgium, France and the Netherlands – is reported for the first time. The morphology, geological provenance, petrographic characteristics and distribution patterns are discussed, based on a comparative analysis with archaeological and geological reference material. The geological analysis identifies a common geological source for the Continental finds: the very fine‐grained, thin‐bedded, flagstone‐like calcareous sandstone beds of the Lower Cretaceous Wealden Clay Formation. These sandstones were, most probably, extracted in the north‐western part of the Weald area. The distribution pattern of the archaeological material implies the importance of personal mobility, with potential military affinities.  相似文献   
6.
Although the aetiology of bone pathologies in cattle is poorly documented, various deformations in the skeleton have been attributed to draught exploitation in the archaeozoological literature. This paper summarizes the results of an osteological study that was undertaken on the feet of modern draught oxen. This led to the definition of a series of draught‐related anomalies. In an attempt to describe the pathologies in a more consistent and quantitative way, a scoring scale for each individual bone pathology was established. The developed method is applied to cattle remains from four Roman and one late medieval site. The distribution of the observed pathological indices (PIs) on the first phalanges is interpreted in terms of the age structure of the cattle populations, and the possible modes of cattle exploitation and meat consumption in various settlement types. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   
7.
Archaeological fish bones reveal increases in marine fish utilisation in Northern and Western Europe beginning in the 10th and 11th centuries AD. We use stable isotope signatures from 300 archaeological cod (Gadus morhua) bones to determine whether this sea fishing revolution resulted from increased local fishing or the introduction of preserved fish transported from distant waters such as Arctic Norway, Iceland and/or the Northern Isles of Scotland (Orkney and Shetland). Results from 12 settlements in England and Flanders (Belgium) indicate that catches were initially local. Between the 9th and 12th centuries most bones represented fish from the southern North Sea. Conversely, by the 13th to 14th centuries demand was increasingly met through long distance transport – signalling the onset of the globalisation of commercial fisheries and suggesting that cities such as London quickly outgrew the capacity of local fish supplies.  相似文献   
8.
The method of hierarchical information integration can be applied to the study of complex decision-making processes in which preference formation is influenced by many attributes of choice alternatives. In this paper, we extend Louviere's (1984) original approach to include the modeling choice processes in addition to judgment processes. Assumptions underlying the original and our extension are discussed and the new method is applied in an analysis of residential choice behavior.  相似文献   
9.
Daily growth increments in fish otoliths have been demonstrated for the first time on Quaternary sagittae from a late palaeolithic site in Egypt and they have allowed us to establish the season of fishing. Transverse sections of tilapia sagittae studied under light-microscope demonstrate that recrystallization during diagenesis renders the majority of the margins unreadable. The well-preserved otoliths, however, all have widely spaced outer growth lines, indicating that the fish died during a period of fast growth which coincides with the flood season. Moreover, counting the daily increments showed that late palaeolithic man captured the animals on the floodplain of the Nile after the maximum of the flood, when residual pools were present.  相似文献   
10.
Throughout the US there is an increasing debate about the nature of urban development, including such aspects as suburban sprawl and continuing central city poverty. This debate is driven by a range of motivations, including concerns about the effect of growth on the environment, quality of life, government efficiency, economic competitiveness, and equity. Several metropolitan areas have developed new governmental and fiscal structures or land use policies to address problems caused by growth, or by inequalities within regions. A detailed case study of Chicago shows how different groups deal with these issues politically. The article concludes with an overview of the policies most likely to be successful.  相似文献   
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