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排序方式: 共有417条查询结果,搜索用时 15 毫秒
61.
Uranium-series age estimates for rock art in southwest China   总被引:1,自引:0,他引:1  
We report the first uranium-series age estimates for rock art in China. Calcite bracketing a paint layer was used to constrain the age of a naturalistic outline hunter-gatherer painting in the Jinsha River area of northwest Yunnan Province (southwest China). The rock paintings in this region are unique in style and content compared with other bodies of rock art in China, which are dominated by Neolithic subject matter. The minimum and maximum ages were determined using isochron techniques on multiple samples of calcite from above and beneath the paint layer. A large painted deer head was dated to between 5738 and 2050 years. This painting and underlying flowstone are superimposed on older paintings that suggest the older paintings are at least 3400 years old, if not older than 5738 years. The results indicate for the first time that Jinsha River rock art is older than other forms of rock art in the region and show that rock art likely extends back to at least the transition from the Palaeolithic to Neolithic in this part of China.  相似文献   
62.
2011年3~4月,安徽省文物考古研究所对安徽泗县刘圩遗址进行了抢救性发掘,揭示一批汉至唐宋遗迹。其中,唐宋汴河北堤的发现,在隋唐大运河泗县段尚属首次;宋代踩踏面及相关遗迹的发现反映了汴河漕运的繁华;北宋末至南宋初土坑墓的发现印证了相关文献记载的汴河废弃时代。  相似文献   
63.
An illustrated methodology for the morphodynamic sectoring of the Neigette River (Québec) Fluvial hydrogeomorphology is little recognized in policy management and planning in Québec. A better understanding would result in more enlightened planning for waterways. The deficiency could result from the fact that too few methodologies have been developed that take account of the particular nature of Québec rivers. This study tests the applicability of a methodology of dividing rivers into homogeneous morphodynamic units. This compartmentalization results from the analysis of longitudinal changes in stream power, sedimentary composition of the banks, channel entrenchment, and planform geometry. The method is tested on a section of the Neigette River, which encompasses a wide variety of forms and processes frequently found in Québec rivers. Results suggest the presence of three morphodynamic sections: wandering with multiple channels, dynamic meandering and stable meandering. The method provides an effective basis for discriminating between these morphodynamic environments and their respective limits. Stream power is the variable with the greatest discriminating capacity. The efficacy of the approach, the ease of its application, and its flexibility make this a valuable tool for the management of fluvial environments.  相似文献   
64.
One of the leading Western observers of Ukrainian affairs, before and after the dis-integration of the Soviet Union, discusses the preceding paper by Anders Åslund devoted to the economic policies of Ukraine after the Orange Revolution. The commentary covers in some detail the pervasive corruption, largely traced to Ukrainian oligarchs but also endemic in the administration and among the military. Relatively recent 2005 polls are cited to illustrate the citizenry's support for some of the government's policies and regulations pertaining to prices, privatization, and organized crime, as well as those showing presidential and ministerial approval ratings. Journal of Economic Literature, Classification Numbers: H10, H80, O52, P30. 16 references.  相似文献   
65.
This paper discusses the artistic and cultural work of one minority author and regional activist, Bengt Pohjanen, and how it constitutes a means for mediating regional identity narratives, constructing Meänmaa, the region straddling the border between Sweden and Finland in the Tornio River Valley. We will approach narrativization as a creative social action, focusing on the performative, social and political aspects of regional stories, and by this means impugning the division between territorial, bounded, and networked, unbounded, conceptualizations of regions. We will follow the narrative plot of Bengt Pohjanen's Meänmaa, pointing out how an artistic and cultural region becomes part of our social reality and how regional consciousness and identity become established and constantly renegotiated within and across national borders.  相似文献   
66.
A new core reduction index is presented, calculated as the ratio of flake scar number to 3D surface area (SDI). The index is tested experimentally on five types of core (blade, discoid, Levallois, biface and multiplatform cores) and then applied to the core assemblages from five sub-stages of the Middle Stone Age at Klasies River Mouth, South Africa. Preliminary results indicate that the SDI possesses the desirable attributes of a successful reduction index and is a significant improvement on traditional proxy measures of core reduction. The results of the archaeological case study confirm previous untested observations that cores from the Howiesons Poort and MSAIII sub-stages are more heavily reduced than preceding and following stages, and that local and exotic raw materials as well as different types of cores are all more heavily reduced during these periods. The SDI fills a significant lacuna in available core reduction measures.  相似文献   
67.
Understanding how to live successfully within our environment is among the most pressing challenges facing contemporary society. This paper probes the problem based on comparative analysis and discusses the relationship between the spatial–temporal distribution of the Neolithic cultural sites and the geographic context in the Hanjiang River Basin in the south of Shaanxi Province, China. Archaeological studies have identified 175 Neolithic cultural sites in the study area, with a sequence of Laoguantai (14C age 8–7 ka BP), Yangshao (14C age 7–5 ka BP) and the late period of the Neolithic Age (14C age 5–4 ka BP). The total number of archaeological sites, the distribution area and the density all showed an early ascending and later descending trend, but the proportion of the number of archaeological sites in the study area to the corresponding value of the entire Shaanxi Province declined sharply. Spatially, these sites were concentrated on the terraces of the Hanjiang River and its main tributaries with an altitude of 400–800 m. Multiple data were integrated to clarify the critical effects of tectonic and geomorphologic conditions on the distribution of the Neolithic sites. Further comparisons revealed the correlation of Holocene climate change and environmental evolution with the Neolithic cultural succession in the study area that ameliorated conditions to generally promote the development of the primitive culture while degeneration coincided with the culture's transition or interruption. The discussion on the origin of the primitive culture and the temporal–spatial distribution corresponding to the regional culture differentiation sheds light on the complex and dynamic human–nature interaction system during the Neolithic Age, thus emphasising the wider field-based investigation and high-resolution reconstruction works of the palaeoclimate and palaeoenvironment in the future.  相似文献   
68.
Abstract

The Topographical Survey of the Orange Free State, executed by the British War Office between 1905 and 1911, was not only one of the first but also one of the finest topographical surveys to be undertaken in British colonial Africa. The motivation for this undertaking stemmed from three sources: the personal interest of Sir David Gill (H.M. Astronomer at the Cape) in the measurement of the arc of the 30th meridian; Britain's imperialistic intervention in South Africa which resulted in the South African War (1899–1902) against the Boer Republics and which stressed the need for reliable military maps for warfare as well as for the general defence of the new colonies; and the need for accurate maps for purposes of colonial administration and land tenure. The survey took five and a half years to complete, and the 1: 125,000 series (G.S.G.S. 2230) that was compiled represented the only accurate maps of this part of the continent for almost seven decades.  相似文献   
69.
河西地区主要水系之一石羊河及其支流,在历史上曾使用"谷水"、"马城河"、"五涧谷(水)"、"三岔河"等名称,沿用至今的"石羊河"一名迟至清代前中期方才出现。"石羊河"之名,首先出现在流域下游镇番县的地方志中,命名的初衷则是为处于上游武威县境内的河流定名,其指代对象存在逐步明确的过程。上游武威县对"石羊河"名及其指向,经历了从不在意到接受、并有所延展的演变历程。"石羊河"名的出现,与下游镇番县河源水权观念的兴起存在密切关联。塑造河名是上、下游水资源权利关系生成中,下游构建自身水权的策略之一。  相似文献   
70.
黑河流域居民生活质量研究   总被引:1,自引:0,他引:1  
彭浩  曾刚  徐中民 《人文地理》2009,24(4):66-71
以《Calvert-Henderson生活质量指标》一书为理论指导构建了生活质量评价指标体系,通过开展生活质量问卷调查及查找相关统计资料,运用主成分分析法确定指标的权重,研究了我国西北地区第二大内陆河流域-黑河流域城乡居民2004年的生活质量。具体的评价结果是:黑河流域城镇居民生活质量明显高于农村;黑河流域城市居民生活质量表现出中游高于上游和下游;黑河流域农村居民生活质量以乡镇为单位计算差异显著;黑河流域农村居民生活质量中游略好于上游、下游;影响黑河流域城乡居民生活质量的主要因素是收入、教育和住房。  相似文献   
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