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1.
This study examined landcover change during 1940–1988 in two contiguous landscapes of approximately 12,400 hectares in central Ohio, USA: an inertial till plain area and a more dynamic moraine area. Agriculture dominated both landscapes throughout, however, the cover of natural vegetation and urban-suburban development increased over time on the moraine while natural vegetation decreased and agriculture increased on the till plain. Markov process models for landcover change were constructed for three 14–17-year time intervals and for the entire forty-eight-year study period. Probabilities of self-replacement for agricultural lands (0.91–0.97) were higher and those for forests (0.54–0.65) lower than those reported for other landscapes. Predictions of landcover percentages for fifty years in the future were made using Markov process models derived from actual cover changes in 1940–1957, 1971–1988, and 1940–1988. All three models produced similar predictions for the inertial till plain area. In contrast, the three models' predictions differed considerably for the moraine area. Only the 1971–1988 transition matrix was sensitive to increases in urbanization and reforestation which began on the moraine in the 1970s. These results indicate that reliance on lengthy study intervals and net rates of change can obscure spatial and temporal patterns of landcover change that are caused by natural and socioeconomic factors operating on shorter time scales.  相似文献   
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The Qhapaq-Ñan Project promotes the integration of shared cultural values among six countries: Argentina, Chile, Bolivia, Peru, Ecuador and Colombia. These countries are collaborating to nominate the Main Andean Road or “Qhapaq-Ñan” for inclusion on UNESCO’s World Heritage List. Although the participants envision local and Indian communities as the true beneficiaries of the project, and the archaeological effort is already under way, communities associated with the road have not been involved. (At the very moment we are editing this article (March 2007) Argentina is holding the first meeting about a project that is already five years old, with some of the Indian communities of the territories where the project will be carried out. The participation, however, was far below what we expected.). Following the guidelines of the World Archaeological Congress and the current emphasis of many heritage professionals on community participation, we strongly advise that these dynamics must be changed and that the program must be developed jointly with affected communities from the beginning of the project and not in subsequent steps, or (even worse) once the project already taken shape.  相似文献   
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This paper investigates evidence for subsistence and settlement activities in the Levantine Middle Epipalaeolithic through the application of stable isotope analysis to human and non-human remains from the site of 'Uyun al-Hammam, northern Jordan. In general, bone from the site suffers a high degree of diagenesis and collagen could not be extracted for analysis here. Carbon and oxygen isotopic values from human tooth enamel samples were variable, but within expected values for the Middle Epipalaeolithic, whereas animal carbon and oxygen isotopic values varied widely, most likely due to hydrological and climatological factors. Carbon and isotopic values for the human samples indicated a predominantly C3 plant dietary input, while animal samples appeared to have varying amounts of C4 inputs into their diet. This is the first isotopic analysis conducted on material from the Middle Epipalaeolithic of the southern Levant and, as such, even results constrained by temporal and climatological variants within the region contribute to the overall knowledge of settlement and subsistence strategies during this cultural period.  相似文献   
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A correct sex assignment of a given bone or bone fragment is of paramount importance for the archaeologist, anthropologist and in forensic medicine. Discriminant functions, combining several anthropometric measurements obtained from individuals with known sex are useful tools for this purpose, but it is essential to know exactly the sex from which the measures are obtained. This is an easy task in modern populations, but it is problematic in ancient ones, since even when the entire skeleton is available, diagnosis of sex is not 100% accurate. Sexing by genetic methods by amplifying the first intron of the amelogenin gene constitutes a much more accurate method for sexing bones and may be the gold standard for further elaboration of discriminant functions which may serve for sexing new bones dug up in future excavations. With this aim we have genetically sexed 52 (out of 59) tibiae belonging to the prehispanic population of El Hierro, in the Canary Islands, identifying 18 women and 34 men, and then, performed discriminant functions combining several anthropometric variables. These functions show a high accuracy in sex diagnosis (94.2%; area under ROC curve = 0.954 with the best of the functions), so that they allow correct sexing of tibiae or tibiae fragments (only proximal third, distal third or midshaft). Thus, genetic sexing obviates the problem of finding an accurate gold standard for the elaboration of discriminant functions for ancient bones. This method could be applied to other populations of different antiquity and different ethnicity.  相似文献   
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Neves, J.P., Anelli, L.E., Pagani, M.A. & Simões, M.G., 2014. Late Palaeozoic South American pectinids revised: biostratigraphical and palaeogeographical implications. Alcheringa 38 ISSN 0311-5518.

A revision of the late Palaeozoic South American pectinid Heteropecten multiscalptus (Thomas) and the establishment of Heteropecten paranaensis sp. nov. have important implications for the relationship between faunal realms within South America. Late Palaeozoic bivalve faunas occur in three distinct realms in South America: a Central Gondwanic Realm with endemic taxa showing affinities to Australia, New Zealand, South Africa and Namibia, a cold Perigondwanic Realm, and a warm Extragondwanic Realm with tethyan-like affinities similar to faunas of the American Midcontinent. In South America, faunas east of the southern Andes belong to the first two realms and previous interpretations of bivalve faunas suggested biocorrelations with those of the Extragondwanic Realm because they shared the taxon Heteropecten multiscalptus (Thomas). A revision of the Peruvian and Brazilian material does not confirm this. Instead, a re-analysis suggests that two species are present, rather than one: Heteropecten multiscalptus in the Cerro Prieto Formation, Amotape Mountains (Peru; Extragondwanic Realm), and Heteropecten paranaensis sp. nov. in the upper part of the Itararé Group, Paraná Basin (Brazil; Central Gondwanic Realm). Thus, the correlation between the late Palaeozoic faunas of the Central Gondwanic and Extragondwanic Realms in South America can no longer be supported. Heteropecten paranaensis sp. nov. lived in a siliciclastic-dominated, cold, epeiric sea of Brazil and Argentina, and is morphologically similar to some Australian species, whereas the Peruvian H. multiscalptus thrived in the warm seas of the Extragondwanic Realm.

Jacqueline P. Neves [], Instituto de Geociências e Ciências Exatas, Universidade Estadual Paulista, Rio Claro campus, SP, Brazil, 13506-900; Luiz E. Anelli [], Instituto de Geociências, Universidade de São Paulo, 05508–080, Brazil; M. Alejandra Pagani, [], CONICET-Museo Paleontológico Egidio Feruglio (MEF), U9100GYO, Chubut, Argentina; Marcello, G. Simões [], Instituto de Biociências, Universidade Estadual Paulista, Botucatu campus, SP, 18618-970, Brazil. Received 19.7.2013; revised 12.11.2013; accepted 19.11.2013  相似文献   
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We exploit the GEOSTAT 2011 population grid with a very high 1 km2 resolution to document that Spain presents the lowest density of settlements among European countries. Only a small fraction of the Spanish territory is inhabited, particularly in its southern half, which goes hand in hand with a high degree of population concentration. We uncover through standard regression analysis and spatial regression discontinuity that this anomaly cannot be accounted for by adverse geographic and climatic conditions. The second part of the paper takes a historical perspective on Spain's settlement patterns by showing that the spatial distribution of the population has been very persistent in the last two centuries, and that the abnormally low density of settlements with respect to European neighbors was already visible in the 19th century, which indicates that this phenomenon has not emerged recently as a consequence of the transformations associated with industrialization and tertiarization. Using data on ancient sites, we find that Spain did not feature scarcity of settlements in comparison to other countries in premedieval times, suggesting that its current anomalous settlement pattern has not always existed and is, therefore, not intrinsic to its geography.  相似文献   
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This paper presents strong and well dated evidence of the presence of Micropogonias furnieri in areas that are currently out of distribution. This evidence comes from hunter–gatherer archaeological sites along the north Patagonian coast (Argentina). Our results allow us to determine a change in the spatial distribution of M. furnieri during the Holocene, which are possibly linked to biogeographic changes in a set of species at regional level. Finally we discuss the potential for archaeological evidence in the service of spatial and biogeographic studies of different species.  相似文献   
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Wooden snuff trays from San Pedro de Atacama (SPA) in northern Chile are objects of particular museological value. Computed tomography (CT), a non-destructive analytical technique useful in the analysis of archaeological objects in which physical tampering is not desirable, was used to study provenience of wood, quality of craftmanship, taphonomic processes and nature of gemstone inlays in a group of snuff trays. While wood used in the manufacture of trays was mostly exogenous to SPA, gemstones used in inlays were likely of local origin. These findings support the active exchange of goods proposed for the south-central Andes region. Several features revealed in the trays support the view that craftsmen producing them were skillful artisans.  相似文献   
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