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611.
Matthew C. Peros Samuel E. Munoz Konrad Gajewski André E. Viau 《Journal of archaeological science》2010,37(3):656-664
Large radiocarbon datasets are increasingly used as a paleodemographic proxy, although potential sources of bias in such records are poorly understood. In this paper, we use more than 25,000 radiocarbon dates extracted from the Canadian Archaeological Radiocarbon Database (CARD) to estimate long-term population trends in North America, while critically examining biases in such records. The frequency distribution of CARD dates shows a positive curvilinear pattern, such that older dates exist in lower numbers than more recent dates, which in part reflects the removal of cultural carbon from the archaeological record through processes such as erosion and dissolution. The average annual growth rate of radiocarbon dates in CARD was calculated and used to derive estimates of the population of North America from the Paleo-Indian to the Contact Periods. While taphonomic bias has likely affected the CARD data, other factors, such as the overrepresentation of Paleo-Indian and Archaic radiocarbon dates, may have offset any bias due to taphonomy. A quantitative reconstruction of Native American population shows that population increased rapidly around 2000 cal yr BP, reaching a maximum of 2,500,000 people by ~AD 1150. From this time until European contact, the population declined, possibly due to the effects of increased sedentism and population density. 相似文献
612.
Young people’s everyday landscapes of security and insecurity 总被引:1,自引:0,他引:1
Peter Hopkins Kathrin Hörschelmann Matthew. C Benwell Catherine Studemeyer 《Social & Cultural Geography》2019,20(4):435-444
AbstractDebates about ‘security’ rarely feature children or younger people, whilst research with children and young people seldom focuses upon issues traditionally found within security studies. Building upon long-standing debates about political geographies of youth and political participation as well as feminist geopolitics and emerging discussions about children’s and young people’s geopolitics, we chart young people’s everyday landscapes of security and insecurity. Key themes explored here include: secure pasts and insecure futures; ontological security and insecure selves; online security and digital insecurities; home(land) securities and insecure households and families; and global securities and insecure worlds. 相似文献