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81.
A vibrant artisanal fishery of the brackish water marsh clam (Polymesoda acuta) is located in the lower Río Tempisque, Costa Rica. Fishermen harvest clams from shoals according to tidal and lunar cycles. They take most clams directly to riverside processing stations to be cooked and sold as salted meat, although some cooked clams are dried, and others sold live. Processing activities result in the formation of shellmounds that share significant similarities and some differences with ancient marsh clam shellmounds of coastal Chiapas, Mexico. In this study, procurement and processing activities are described and quantified, revealing the substantial amount of labor and skill involved in the modern fishery. Implications for archaeological preservation and predictions from optimal foraging theory are evaluated.  相似文献   
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The aim of the present article is to reconsider the interpretation of the Greek word halourgos (?λουργ??) and its relation to textiles and purple dye by reinvestigating its recordings in Greek epigraphy and the papyri, as well as comparative examples from Greek literary sources, in the period from the fourth century bc to the seventh century ad — thus combining the source material from ancient Greece and the Greek-speaking part of the Roman world. This will illustrate the wealth of information one can get from the exploration of one single word: not only on the significance and appearance of textiles and garments in the ancient world from Greece to Egypt, but also on the diversity of colours and the subtleties in their use and terminology.  相似文献   
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This article examines the decision in May 1960 by the British colonial secretary, Iain Macleod, to accelerate dramatically the independence timetable for Tanganyika. Making extensive use of recently released archive material, it looks at the key factors behind this largely neglected but nevertheless significant episode, seeking to demonstrate that, despite Macleod's subsequent recollection of events, there was a clear policy change in May 1960; that it was for the main part external nationalist and internationalist pressures which led to the policy change; that, importantly, newly identified short-term factors of a change of heart by nationalist leader Julius Nyerere, events in Somaliland and the need to demonstrate positive Commonwealth credentials were the immediate and decisive reasons behind the acceleration; and that, in explaining the advancement, it is valuable to understand why and how individual factors contributed to the policy change and how they worked together.  相似文献   
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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   
85.
Invasive vegetation species can lead to major changes in the geomorphology of coastal systems. Within temperate estuaries in the southern hemisphere, especially Australia and New Zealand, the cordgrass Spartina spp. has become established. These species are highly invasive, and their prolific growth leads to the development of supratidal environments in formerly intertidal and subtidal environments. Here, we quantified the impact of Spartina invasion on the geomorphology and sequestration capacity of carbon in the sediments of Anderson Inlet, Victoria, Australia. Spartina was first introduced to the area in the 1930s to aid in land reclamation and control coastal erosion associated with coastal development. We found that Spartina now dominates the intertidal areas of the Inlet and promotes accretion (18 mm/year) causing the formation of over 108 ha of supratidal islands over the past 100 years. These newly formed islands are calculated to potentially contain over 5.5 million tonnes of CO2 equivalent carbon. Future management of the inlet and other Spartina‐dominated environments within Australian presents a dilemma for resource managers; on the one hand, Spartina is highly invasive and can outcompete native tidal marshes, thereby warranting its eradication, but on the other hand it is likely more resilient to rising sea levels and has the potential for carbon sequestration. Whether or not the potential advantages outweigh the significant habitat change that is anticipated, any management strategies will likely require additional research into costs and benefits of all ecosystem services provided by Spartina including in relation to nutrient cycling, shoreline stabilisation, and biodiversity as well as in response to the longevity of carbon found within the sediments.  相似文献   
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