998 resultados para central Xinjiang


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新疆中部地区位于西北内陆干旱一半干旱区,是欧亚大陆的地理中心,是中纬度内陆干旱区代表性区域,也是全球变化敏感区域之一,基本特点是气候干旱、水资源匮乏、植被稀少、荒漠广布,生态系统脆弱。在研究区域内,天山山脉海拔高度差异5 000 m左右,随海拔梯度下降依次出现高山冰雪带、高山亚高山草甸带、森林带、草原带、荒漠带、沙漠带等明显完整的植被垂直带,是开展现代孢粉学和植被变化研究的理想地点。本报告在立足于该区前人工作的基础上,从表土花粉、空气花粉和现代植被之间的关系入手开展现代孢粉学研究,探讨了花粉与植被的关系。 在研究区内,选择新疆阜康市和吉木萨尔县为研究地点,设计了一条从天山博格达峰附近雪线开始直至古尔班通古特沙漠长约100 km、宽约20 km的样带。沿样带,从高山座垫植被和草甸带开始,经过中海拔地带的云杉林,置到低海拔的荒漠,在山地海拔每下降20~100 m采集一个表土花粉样品,平原每间隔10~20 km采集一个表土花粉样品,同时做现代植被调查,共采集80个表土花粉样品和调查了86个现代植被样方;在天山乌鲁木齐河河源区的大西沟,从一号冰川前缘开始,沿山谷向下直到谷口,按海拔100 m间隔采集了14个表土样品,对表土花粉与植被之间的关系进行了探讨。为了弄清空气花粉传播、散布与气象因子和植被的关系,沿样带从高山到沙漠分别在天池气象站、中国科学院阜康荒漠生态系统定位研究站和北沙窝草炭试验地设置了三个风标式空气花粉收集器,从2001年7月至2002年7月连续收集空气花粉雨,收集了跨2个年度1周年的1 14个空气花粉样品,依据分析结果研究了空气花粉的传播和散布规律以及与表土花粉和植被之间的关系,这在新疆地区乃至全国尚属首次。 根据表土花粉分析结果和现代植被样方资料的分析以及天山中段主要植物种类沿海拔高度的分布特征,天山中段北坡垂直植被带谱为:高山座垫植被(>3 400 m)、高山亚高山草甸(3 400-2 700 m)、山地云杉林(2 700-1 720 m)、森林草原过渡带(1 720-1 300 m)、蒿类荒漠(1 300-700 m)和典型荒漠(<700 m)。表土花粉谱基本上反映了相同海拔高度的现代植被带,特别是在云杉林带,表土中雪岭云杉(Picea schrenkiana)花粉占优势;在蒿类荒漠植被带表土中蒿属(Artemisia)植物花粉非常丰富;在典型荒漠植被带的表土中藜科(Chenopodiaceae)植物花粉占绝对优势,因此可依据这些建群种植物花粉含量峰值的位置划分植物群落。 空气花粉样品分析结果表明:空气中花粉主要是现生植物当年生长产出的花粉,盛花期的花粉数量能较好地反映当地的植被状况。空气中的乔木植物花粉主要有云杉(Picea),其次是柳属(Salix);灌木草本植物花粉主要是藜科和蒿属,其次是菊科(Compositae)、禾本科(Gramineae)、柽柳科(Tamaricaceae)和麻黄属(Ephedra);空气中的花粉数量与植物的花期相对应,云杉等乔木植物盛花期在夏季5月末至7月初,灌木草本植物盛花期在夏秋季节。气温、降水、风速和风向等气象条件对空气中花粉数量有很大影响,其中风速和风向影响最大。从空气花粉和表土花粉的分析结果与现生植被对比,新疆中部地区的山谷上升气流是导致花粉“爬坡”现象的主要动力,在一定条件下,上升气流搬运花粉的数量和能力是十分可观的。 空气中的花粉是现生植物当年生长产出的花粉,表土中的花粉是多年花粉落地沉积的积累,植物盖度大,该植物的花粉在空气中和表土中数量相对就大。在新疆中部地区,空气花粉能反映当地和附近周边方圆约50 km的植被状况,其花粉组合特征与表土花粉和当地现生植被分布的对比研究,可以较好地寻找花粉与植被的关系。本研究报告的研究成果不仅为新疆地区的孢粉学研究增添新的内容,而且将有助于合理解释新疆地层中、尤其是第四纪以来的地层孢粉,较客观地恢复过去的植被景观,同时可为本地区的大气环境检测提供有重要价值的参考资料。

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The neighboring regions of Xinjiang and Central Asia, linked historically on the famous Silk Road, later developed separately as a result of the incorporation of the former into China and the latter into the Russian Empire and Soviet Union. Thus, interaction between Xinjiang and Central Asia has been constrained by the nature of the Sino-Russian or Sino-Soviet relationship. However, the demise of the Soviet Union--which resulted in the independence of five Central Asian states--and the recent economic reforms in the People's Republic of China suggest dramatic new possibilities for interregional cooperation.^ In this thesis, an historical and comparative approach is employed to study Chinese policies in Xinjiang and Soviet policies in Central Asia, and concludes that despite several decades of separate development, the common ethnic and religious origins of the indigenous peoples and their former ties will facilitate greater interaction between the two regions. ^

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Xinjiang, once described by Owen Lattimore as the "pivot of Asia", has played a strategically important role in China's national defense and security. Historically linked on the famous Silk Road with Central Asia, Xinjiang was crucial to East-West economic and cultural exchanges. During the period of Russian/Soviet expansion into Central Asia and Sino-Soviet rivalry, China's need for Xinjiang's defense and territorial integrity became paramount, and consequently Xinjiang's economy was relegated to the periphery.^ The demise of the Soviet Union--which resulted in the independence of five Central Asian states--and China's reform suggest dramatic new possibilities for Xinjiang's regional development as well as interregional cooperation. As China has begun to shift regional emphasis to the interior, Xinjiang's economic development will be accelerated. With the growth of Sino/Xinjiang-Central Asian relations, Xinjiang's importance will not only be borne out in terms of defense and security, but more significantly in terms of trade and economics. At the century's end and the beginning of the 21st century, Xinjiang will likely move away from the periphery and play an increasingly pivotal role in the economy. ^

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Early glasses (about 1066 BC-220 AD) unearthed from Xinjiang of China were chemically characterized by using PIXE and ICP-AES. It was found that these glasses were basically attributed to PbO-BaO-SiO2 system, K2O-SiO2 system, Na2O-CaO-SiO2 system and Na2O-CaO-PbO-SiO2 system. The results from the cluster analysis showed that some glasses had basically similar recipe and technology. The PbO-BaO-SiO2 glass and the K2O-SiO2 glass were thought to come from the central area and the south of ancient China, respectively. The part of the Na2O-CaO-SiO2 glass (including the Na2O-CaO-PbO-SiO2 glass) might be imported from Mesopotamia, while the other part might be locally produced. (c) 2005 Elsevier B.V. All rights reserved.

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Esta monografía tiene como objetivo explicar cómo las migraciones transnacionales se han convertido en una amenaza para la seguridad de las ex repúblicas soviéticas de Asia central durante las últimas dos décadas dando lugar a un Complejo de Seguridad Regional (CSR). Mediante la teoría crítica del CSR elaborada por Barry Buzan, se buscará probar que estos flujos migratorios transnacionales han configurado una amenaza compartida para la seguridad de la región debido a su asociación con grupos extremistas islámicos asociados con el terrorismo. La materialización de dicho CSR se manifiesta en la creación de organizaciones regionales con una agenda de seguridad compartida tales como la Organización del Tratado de Seguridad Colectiva y la Organización de Cooperación de Shanghai con el fin de neutralizar estas nuevas amenazas de carácter transnacional.

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This layer is a georeferenced raster image of the historic paper map entitled: Carte de la petite Bukharie et pays voisins : pour servir a l'Histoire générale des voyages, dressée sur les observations les plus récentes par N. Bellin, Ingr. de la Mare., 1749. It was published by Pierre de Hondt in 1750. Scale [ca. 1:8,500,000]. Covers Northwest China, including portions of Xinjiang Uygur Zizhiqu, Gansu Sheng, Qinghai Sheng, Tibet, Inner Mongolia, and portions of India, Kazakhstan, Kyrgyzstan, Uzbekistan, Tajikistan, Afghanistan, Pakistan, and Mongolia. Map in French and Dutch.The image inside the map neatline is georeferenced to the surface of the earth and fit to the Asia North Lambert Conformal Conic coordinate system. All map collar and inset information is also available as part of the raster image, including any inset maps, profiles, statistical tables, directories, text, illustrations, index maps, legends, or other information associated with the principal map. This map shows features such as drainage, cities and other human settlements, territorial boundaries, roads, and more. Relief shown pictorially.This layer is part of a selection of digitally scanned and georeferenced historic maps from the Harvard Map Collection. These maps typically portray both natural and manmade features. The selection represents a range of originators, ground condition dates, scales, and map purposes.

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This layer is a georeferenced raster image of the historic paper map entitled: Eastern Turkistan, specially prepared for the Foreign Department, from India ; published under direction of Colonel F. B. Longe, R. E., Surveyor General of India. It was published by Survey of India in Feb. 1908. Scale [1:2,027,520]. Covers a portion of Central Asia including Xinjiang Uygur Zizhiqu (also known as Chinese Turkestan) and portions of Afghanistan, India, Kyrgyzstan, Pakistan, and Tajikistan. The image inside the map neatline is georeferenced to the surface of the earth and fit to the a modified 'Asia Lambert Conformal Conic' projection with a central meridian of 84 degrees East projection. All map collar and inset information is also available as part of the raster image, including any inset maps, profiles, statistical tables, directories, text, illustrations, index maps, legends, or other information associated with the principal map. This map shows features such as drainage, cities and other human settlements, railroads, territorial boundaries, shoreline features, and more. Relief shown by spot heights. This layer is part of a selection of digitally scanned and georeferenced historic maps from the Harvard Map Collection as part of the Open Collections Program at Harvard University project: Islamic Heritage Project. Maps selected for the project represent a range of regions, originators, ground condition dates, scales, and purposes. The Islamic Heritage Project consists of over 100,000 digitized pages from Harvard's collections of Islamic manuscripts and published materials. Supported by Prince Alwaleed Bin Talal and developed in association with the Prince Alwaleed Bin Talal Islamic Studies Program at Harvard University.

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Various dates (966-1219 [1558-1804]). Addressed to various local rulers in Yarkand and Kashgar.