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1.
大约以公元前2200年为界, 老虎山文化可分为前、后两大期.前期稳定发展,对外影响有限;后期向南强烈扩张,其陶双鋬鬲、卜骨和细石器镞更流播至黄河中下游广大地区.老虎山文化后期对外扩张的加强和这一时期气候日渐干冷有关.  相似文献   
2.
One of the main factors involved in entheseal changes (EC) aetiology may be related to the physiological limits of biomechanical loading fixed during bone development, such that higher load during childhood and the adolescent growth spurt leads to a lower frequency of EC during adulthood. In this sense, it is possible that ECs may be related to overloading beyond an individual's normal physiological limits as established during childhood and adolescence. This meta‐analysis tested this aetiological possibility by studying the influence of terrain on the entheses of the lower extremities. The hypothesis is that individuals who inhabited rugged terrain have lower EC than those living in flat terrain. This is because biomechanical loads associated with rugged terrain will lead to a higher normal capacity (defined during skeletal development) mitigating the probability of overloading compared to those living in flat terrain who will therefore have a higher frequency of ECs. To test this, papers reporting EC frequencies in the lower limbs were analysed alongside the local terrain. Terrain was defined into two categories: flat or rugged based on altimetry profile, i.e. the average elevation gains and losses along four specific paths (North‐South, East‐West, Northwest‐Southeast, Southwest‐Northeast). Odds ratios were calculated to compare rugged and flat terrain. The overall results are consistent with the hypothesis that overloading is a factor in EC aetiology. However, when the analysis is conducted by sex and side, this general trend does not always occur. Limitations such as the lack of standardized age ranges could be affecting the outcome, i.e. older individuals have a higher frequency of ECs. The findings of this analysis suggest that the theoretical assumptions associated with the cause of ECs require further testing and evaluation. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   
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Z. Nerudová 《Archaeometry》2020,62(2):410-426
This paper compares the quantification of different raw materials in a chipped stone assemblage by weight and by number at the site of Brno-Štýřice III in Moravia, Czech Republic. The use of the same reduction technology for all raw materials means that the Brno-Štýřice III assemblage is a good case study. The result demonstrates that semi-local raw material tends to dominate numerically, but in terms of weight, there is a significant change in the predominant raw material. The paper contextualizes the results in relation to other assemblages and discusses the possible reasons for this phenomenon.  相似文献   
5.
Communities living on remote islands are often viewed as among the most exposed and vulnerable to climate change impacts. This study uses the Sustainable Livelihoods Framework to investigate how indigenous communities living on two physically different islands in Torres Strait, Australia, experience what they consider to be the impacts of climate change in relation to their daily lives. During this process, a series of natural, physical, and socio‐cultural limits and barriers to climate change adaptation were identified on Boigu, a low‐lying mud island inundated by the sea during high tides and storm surges. As a volcanic island, Erub's elevation is higher but significant community infrastructure, housing, and cultural sites are located on the low coastal fringe. No immediate limits to climate change adaptation were identified on Erub, but physical and socio‐cultural barriers were revealed. Limits to climate change adaptation occur when adaptation actions fail to protect the things valued by those affected, or few adaptation options are available. Barriers to climate change adaptation may be overcome if recognised and addressed but can become entrenched limits if they are ignored. Within the participating communities, such limits and barriers included (a) restricted adaptation options due to limited access to particular livelihood assets; (b) difficulty engaging with government processes to secure external support; and (c) people's place‐based values, which evoke a reluctance to relocate or retreat.  相似文献   
6.
The extent to which North Atlantic Holocene climatic perturbations influenced past human societies is an area of considerable uncertainty and fierce debate. Ireland is ideally placed to help resolve this issue, being occupied for over 9000 yr and located on the eastern Atlantic seaboard, a region dominated by westerly airflow. Irish bog and lake tree populations provide unambiguous evidence of major shifts in surface moisture through the Holocene similar to cycles recorded in the marine realm of the North Atlantic, indicating significant changes in the latitude and intensity of zonal atmospheric circulation across the region. To test for human response to these cycles we summed the probabilities of 465 radiocarbon ages obtained from Irish archaeological contexts and observe enhanced archaeological visibility during periods of sustained wet conditions. These results suggest either increasing density of human populations in key, often defensive locations, and/or the development of subsistence strategies to overcome changing conditions, the latter recently proposed as a significant factor in avoiding societal collapse. Regardless, we demonstrate environmental change is a significantly more important factor in influencing human activity in the landscape than has hitherto been acknowledged.  相似文献   
7.
This article focuses on the presence of humans in Siberia and the Russian Far East at the coldest time of the Late Pleistocene, called the Last Glacial Maximum (LGM) and dated to c. 20,000–18,000 rcbp. Reconstruction of the LGM environment of Siberia, based on the latest models and compilations, provides a background for human existence in this region. Most of Siberia and the Russian Far East at c. 20,000–18,000 rcbp was covered by tundra and cool steppe, with some forest formations in the river valleys. Climate was much colder and drier than it is today. Eighteen Upper Paleolithic sites in Siberia are radiocarbon dated strictly to the LGM, and at least six of them, located in southern parts of western and eastern Siberia and the Russian Far East, have solid evidence of occupation during that time span. It seems clear that southern Siberia was populated by humans even at the height of the LGM, and that there was no dramatic decline or complete disappearance of humans in Siberia at that time. The degree of human adaptation to periglacial landscapes in the mid-Upper Paleolithic of northern Eurasia was quite high; humans coped with the cold and dry environmental conditions using microblade technology, artificial shelters, tailored clothes, and megafaunal bones as fuel. An erratum to this article can be found at  相似文献   
8.
This paper examines 20th-century environmental change in the subhumid southwestern Canadian Plains, specifically in relation to the dominant agricultural landscape and to the climate of the past millennium as reconstructed from proxy data. Anthropogenic landscape change in the last century has been dominated by the conversion of grasslands to ranchland and cropland. This has heightened landscape vulnerability to climatic fluctuations, especially drought. Instrumental climate records, extending back to the 1880s, highlight the variability of precipitation in this region. Proxy environmental records, derived from lake cores and tree-ring analysis, extend this picture into the last millennium and show that drought has been a recurring theme of the Prairie climate. Tree-ring records suggest that some droughts in the last millennium may have exceeded in severity any in the instrumental record. The sustainability of Prairie agriculture depends on adaptation to the amplitudes of climatic change and variability evident in these proxy records. Dans cet article nous examinons les changements environnementaux qui sont survenus pendant le 20ème siècle dans les plaines canadiennes sèches du sud-ouest, spécifiquement par rapport au paysage agricole dominant et au climat du dernier millénaire qui a été déterminéà partir de données de procuration. La transformation des prairies en ranchland et cropland est le changement du paysage le plus important dont l'homme est responsable, pour le dernier siècle. À cause de ce changement, le paysage est plus vulnérable aux fluctuations climatiques - à la sécheresse en particulier. Les enregistrements instrumentaux de climat, qui reculent jusqu'aux années 1880, mettent en évidence la variabilité des précipitations dans cette région. Les enregistrements environnementaux de procuration, dérivés d'échantillons pris dans les lacs et de la dendroanalyse, étendent cette image dans le dernier millénaire et prouvent que le thème de la sécheresse est apparu souvent dans les analyses du climat du prairie. Les enregistrements de boucles d'arbre suggèrent que, dans le dernier millénaire il y avait des sécheresses qui étaient peut-être si sévères que les instruments n'ont pas pu les enregistrer. Si l'agriculture veut survivre comme entreprise dans les prairies, il faudra qu'elle s'adapte aux amplitudes de changement et de variabilité du climat qui ont été constatées dans les données de procuration.  相似文献   
9.
A quantitative bioenvironmental study of cranioskeletal size has been made of a latitude-ordered sequence of 14 series of adult skeleton sets (N=305): the archaeological remains of aboriginal maritime peoples inhabiting the west coast of North America between southern California and the Arctic. Of eight osteometric parameters of cranioskeletal size developed, the most important are partial skeleton volume (PSK) and cranial capacity (CC); and the principal bone-affecting environmental factors are the northerly climate (CLIM2c), the reconstructed diet deficient in calcium and overabundant in animal foods and vitamin D (DIET3c), and demographic stress (DSg). Prior research has demonstrated that cranioskeletal size increases with geographical latitude and decreases under dietary calcioprivation and unphysiologically high birth rates. Upon linear multifactorial statistical analysis our main finding, limited to the Amerindian subsequence (n=11 series) from the Santa Barbara Channel, the San Francisco Bay Region and the Northwest Coast, is that PSK and CC vary in direct proportion to CLIM2c, and inversely with DIET3c and DSg. Controlling for the latter two osteoantitrophic factors, coastal Amerindian female PSK rises by 9% between 34 and 54°N latitude, CC by 5%; and the male incremental rates are somewhat higher, 13 and 10%, respectively. This newly discovered climate-dependent race cline, an example of Bergmann's Rule, is interpreted as factual evidence of a mid-Wisconsin or earlier arrival date for the first Palaeoindians. Cranioskeletal size of the very small (n=3 series) Western Eskimo subsequence approximates the northernmost values of the coastal Amerindian distribution. © 1998 John Wiley & Sons, Ltd.  相似文献   
10.
The last decade has witnessed a proliferation of research into the human dimensions of climate change in the Arctic. Much of this work has examined impacts on subsistence hunting, fishing, and trapping among Canadian Inuit communities. This scholarship has developed a baseline understanding of vulnerability and adaptation, drawing upon interviews with community members and stakeholders to identify and characterize climatic risks and adaptive strategies. To further advance this baseline understanding, new methodologies are needed to complement existing research if we are to capture the dynamic nature of how climate change is experienced and responded to, and fully engage communities as equal partners. Longitudinal studies, community‐based monitoring, and targeted adaptation research offer significant promise to advance understanding. These methodologies provide a strong basis for developing meaningful partnerships with communities, the co‐production of knowledge, and empowerment for adaptation: essential components of community‐based participatory research.  相似文献   
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