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1.
This paper is concerned with the products of a number of Neolithic quarries in highland Britain. It investigates the claim that the scale of axe distribution was partly the result of social factors which resulted in these artefacts gaining an added value in areas remote from their sources. One case study considers the sequence of production in Cumbria, in relation to the tensile strength of the rock quarried in different parts of the region. It shows that these considerations had only a limited influence over the choice of stone source and the scale on which it was worked. A second study compares the tensile strength of the main raw materials used for making non-flint axes with the extent to which these sources were actually exploited. Again there is only a limited relationship between the two, suggesting that social factors may indeed have been important.  相似文献   

2.
陶器是新石器时代的广域性文化遗存之一,明显改变了史前人类包括饮食结构在内的诸多生活方式,并促进了史前文化的繁荣与发展,因而制陶术也被视为史前人类的重大发明之一.以往对制陶技术的研究多集中在制坯成型工艺方面,陶窑结构虽也被纳入考察的范畴,却未能充分考虑烧制技术与陶窑结构之间的内在联系,似乎一直没有把握住陶窑形态结构演变的核心特征.中原地区(本文主要指河南及山西中南部)不仅是新石器时代文化发展的重要区域,也发现有裴李岗文化以来各个阶段的史前陶窑遗存,为探讨史前陶窑的结构演变及烧制技术提供了较系统的实物依据.本文在充分考虑烧制技术的基础上,通过陶窑形态结构分类,力求把握其结构演变的核心特征及演变规律.  相似文献   

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ABSTRACT Distributions of city sizes are usually characterized by their Pareto index. This, however, turns out to be a rather restrictive view, for the Pareto distribution is known to become singular whenever the Pareto index becomes smaller than one, a case which is fairly frequent in empirical distributions. We show that the introduction of finite Pareto distributions in which city sizes are bounded from above solves a number of difficulties encountered by the rank-size rule and by the unbounded Pareto distribution. Combined with the use of finite Pareto distributions, the green-belt model that has been introduced previously is reexamined. It implies definite constraints for the long-run evolution of urban systems; it is in the cases of countries experiencing a process of fast urbanization that these constraints are of greatest significance. The implications of the model are confronted with empirical evidence concerning the evolution of urban systems in major industrialized countries during the nineteenth and twentieth centuries.  相似文献   

4.
汉文化为中心的唐代文化大融合   总被引:4,自引:2,他引:2  
张雪莲 《人文地理》1997,12(3):30-33
唐文化是我国传统文化发展的高峰,也是居于当时世界的领先地位。它有着其独特的色彩和先进性。本文着重从地理环境的高度来分析唐代文化生态及文化融合,分析文化与地理环境内在的机制和规律。从而在面对现代外来文化冲击的情况下,更理性地安排人类文化活动空间,并用以改造环境,丰富本土文化,为文化发展创造一个良好的环境。  相似文献   

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Humphrey-Hawkins, enacted into law as the Full Employment and Balanced Growth Act of 1978, is the most important step the Federal government has taken for overall economic coordination since passage of the Employment Act of 1946. The centerpiece of the new law is specific goals for unemployment and inflation. All Federal programs and policies are to work toward achieving a 3 percent adult and 4 percent overall jobless rate within five years, and inflation rates of 3 percent by 1983 and 0 percent by 1988. The present article outlines the major changes made in Humphrey-Hawkins from its introduction in June 1974 to its enactment in October 1978, the contents of the Full Employment and Balanced Growth Act of 1978, and the politics surrounding its passage.  相似文献   

7.
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   

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中原鸟影     
良好的生态环境为生物多样性提供了物质保障,一年四季各种鸟类不断在此繁衍生息。这里数量最多好还是雁鸭类,每到迁徙季节,成千上万的大雁和野鸭都会汇集于此,每天清晨成群结队地到附近麦地里觅食,然后随着落霞返回水面。  相似文献   

10.
Sixteenth- and seventeenth-century European blue glass trade beads from aboriginal sites in the eastern Great Lakes area of North America have been analysed non-destructively using low neutron dose instrumental neutron activation analysis, so that the beads could be returned to their keepers. Dark blue (cobalt-coloured) beads are readily separable from turquoise (copper-coloured) beads. Differences in the chemistries of the turquoise blue beads appear to be useful in separating glass beads from the two centuries. Low calcium, sixteenth-century turquoise beads tend to distintegrate by a leaching of the alkali metals.  相似文献   

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文章以大遗址周边社会空间为研究对象,综述已有研究的基础上对西安地区已开展保护性利用的大遗址周边发展情况进行规律性总结,以空间生产三元辩证法作为分析框架,以三次资本循环为逻辑主线,分析大遗址保护性利用与周边社会空间变迁之间的关系。研究发现:空间生产理论由于其分析社会与空间的双向互馈优势,研究大遗址周边空间实现了精神性、物质性、社会性的统一;保护性利用影响了大遗址周边地区固有社会空间结构,直接动因在于空间资本化驱使下的物质调整;在空间功能演替与生产方式变革驱使下居民社会关系不断嬗变;文物保护制度、土地制度、户籍制度加剧了大遗址周边社会空间结构的复杂性。  相似文献   

13.
ABSTRACT South Africa is one of the wealthiest countries on the African continent. The high national level (and growth) of GDP per capita, however, masks significant differences in economic performance across South Africa's regions. This paper uses (spatial) Markov chain techniques to describe the evolution of the entire cross‐section regional income distribution in terms of its intra‐distributional characteristics during the post‐Apartheid period. The results indicate a heavily diverging regional income distribution. Relatively poor regions are likely to remain poor or become even poorer and the richest regions will maintain their lead in terms of income levels. Explicitly taking account of space furthermore shows that these high‐income regions are acting as local growth poles, absorbing economic activity from their immediate surroundings. Location, trade, education, and the variable fortune of the gold mining industry seem to be important determinants of the observed evolution.  相似文献   

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This article ponders the quest for a new Quebec constitution. It critically analyzes a proposed Quebec constitution introduced as a bill in Quebec's National Assembly in 2007 1 1. Québec Official Publisher (2007a Québec Official Publisher. 2007a. National Assembly, First Session, Thirty-Eighth Legislature, Bill 196, Québec Constitution. Québec Official Publisher http://www.assnat.qc.ca/eng/38legislature1/Projets-loi/Publics/07-a196.pdf (Accessed: 20 May 2008).  [Google Scholar]). and probes the meaning and significance of such a provincial constitution. It makes some comparisons of Quebec's current constitution with those of other provinces and concludes by reflecting on the political prospects and legal effects of such a proposed new constitution. The adoption of a new Quebec constitution, along the lines proposed in 2007 and 2008, should not significantly alter Canada's constitutional order under Canadian law or affect Quebec's current constitutional arrangements with Ottawa and the other provinces. Such a new constitution might, however, come to prevail over other Quebec laws. The objectives of the proposed new constitution are to forge and reinforce Quebecers' sense of a common political identity. The project, however, is not currently at the forefront of discussion.  相似文献   

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ABSTRACT The increase in national earnings inequality in Great Britain over the last two decades has predominantly been a result of increasing earnings inequality within the regions of Great Britain, and not rising inequality between regions. However, there is a severe lack of empirical research exploring the evolution of earnings inequality within regions. This paper investigates the causes of rising within‐region inequality in Great Britain. It examines the changes that have taken place between 1976 and 1995, and regional quantile regressions are estimated to reveal those factors that have contributed to the rise in within‐region inequality.  相似文献   

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<正>I.Transcontinental Connectivity Centuries of continuous warfare and successful expansion turned the Roman Empire into the single dominant power in the Mediterranean basin.Yet,although Roman warfare never fully came to an end,the countryside and the two to three thousand cities of the Empire in Italy and the provinces experienced many  相似文献   

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