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151.
亚洲中部干旱区丝绸之路沿线环境演化与东西方文化交流   总被引:6,自引:0,他引:6  
基于环境记录、考古发现,以及同位素资料,对亚洲中部干旱区丝绸之路沿线的全新世以来的环境变化和东西方文化交流进行了梳理。结果表明,研究区独特的地理环境和环境变化过程,深刻地影响着文化的发展和传播。河西走廊受季风影响,表现出季风—西风过渡带干湿变化的模式,晚全新世气候趋向干旱;从新疆到中亚的丝绸之路沿线的环境变化比较一致:在早全新世(BC 6000以前)主要为干旱环境,植被以荒漠类型占优势;中晚全新世,湿润程度增加,草原植被扩展。新疆和中亚全新世中晚期较为湿润的环境为东西文化交流提供了较适宜的环境基础。得益于环境条件的改善,东西方文化交流融合的进程在BC 2000以后明显加速。在BC 2500-2000期间,东西方农业文化在丝绸之路沿线接触融合,是史前丝绸之路的首次贯通;在BC 2000-1000期间,丝绸之路沿线绿洲地带形成了以小麦—/大麦—粟黍—畜牧为特征的混合型经济特征,并扩散到欧亚草原带,和周围的畜牧业形成鲜明的对照,并持续到历史时期。这种空间分异,是地理环境和东西方文化交流共同作用的结果。在史前时期,东西方农业的相向传播和融合,基本沿着山前地带的绿洲蛙跳式前进。到了历史时期,政治版图的变化是影响丝绸之路的首要因素,但环境变化仍然是不可忽略的因素。  相似文献   
152.
“一带一路”建设研究进展   总被引:25,自引:6,他引:19  
“一带一路”经历了从中国倡议到国际共识的巨大转变,正在成为世界上越来越多国家和政治领袖们探索全球经济治理新模式的平台。伴随这种转变以及“一带一路”建设所取得的成就,“一带一路”研究已经深入到除了基础科学领域外的几乎所有学科。本文根据中国知网(CNKI)数据分析了4年多来“一带一路”研究文献的特征,而后总结了与地理学密切相关的“一带一路”核心议题的研究进展。研究发现:① 自2014年以来“一带一路”研究发文量迅速上升,由2014年的1000多篇飙升到2017年的20000多篇;② 文献比较庞杂,以宏观性、战略性和一般性文献为主,舆论性很高,基于深入研究的高水平学术文献少,还不能很好地支撑“一带一路”建设;③ 对外直接投资、互联互通、“走出去”、全球化、全球治理、命运共同体、人民币国际化等得到的关注较多;④ 地理学在“一带一路”的战略内涵和理论构建、地缘政治经济分析、“中欧班列”、海上航运战略支点、海外投资模式、经贸格局及其经济影响、资源环境问题等方面研究较为深入。最后,本文呼吁加强“一带一路”的理论建构以及建设机制和国别研究,并积极开展中外学者之间“一带一路”研究对话以及合作研究。  相似文献   
153.
Unimpeded trade is one of the cooperation priorities in the Belt and Road Initiative proposed by China. On 15 May 2017, the Joint Communique of the Leaders Roundtable of the Belt and Road Forum for International Cooperation reaffirmed the participants’ shared commitment to build an open economy and ensure free and inclusive trade. The Belt and Road Initiative (BRI) is not only China's new action to drive its open and global development, but also a platform for an increasing number of countries to explore free and inclusive trade and promote a universal, rule-based, open, non-discriminatory, and equitable multilateral trade system. It is therefore important to examine the topological relationship between the BRI and global trade networks. More specifically, this article first analyzes the community structure of trade networks using a community detection algorithm, and then estimates the topological relationship between different trade communities. The findings of this article are as follows. First, this research identified three trade communities and two sub-communities in the BRI trade network, in which China is the core, Russia is the sub-core of the biggest trade community, and India, United Arab Emirates, and Saudi Arabia are cores of the second trade community (South Asia-West Asia). Second, it identified five trade communities in the global trade network, centred on China, USA, Russia, India-United Arab Emirates, and Germany- Netherlands-France-Britain and other European developed countries. Third, the topological analysis indicated that in the global trade network, most BRI countries are attracted by the core nodes of the BRI regions, such as the China, Russia and India-United Arab Emirates core nodes, and have strong trade contacts with BRI countries. Most Central-East European countries are mainly attracted by Germany-Netherlands-France-Britain and other developed European countries with a low penetration of BRI trade. Although some Southeast Asian countries are incorporated into the Asia-Australia-South Africa community with China as the core, they still need to strengthen trade linkages with BRI countries.  相似文献   
154.
Tracking embodied carbon flows in the Belt and Road regions   总被引:3,自引:1,他引:2  
In the past few decades, economic globalization has driven rapid growth of cross-border trade and a new international division of labor, leading to increasing inter- country embodied carbon flows. Multi-region input-output (MRIO) analysis is used to identify embodied carbon flows between major world regions, including seven regions along the Belt and Road (BR), and the spatial distribution of production- and consumption-based carbon intensities. The results show that current embodied carbon flows are virtually all from BR regions to developed countries, with more than 95% of world net embodied carbon exports coming from BR regions. Consumption in the United States and European Union countries induce about 30% of the carbon emissions in most BR regions, indicating that the former bear a high proportion of consumers’ responsibility for the carbon emitted in the latter. For this reason, measuring environmental responsibilities from consumption rather than a production- based perspective is more equitable, while developing countries should be given a louder voice in the construction through dialogue and cooperation, in part in the context of the Belt and Road Initiative, of an inclusive global climate governance system.  相似文献   
155.
The development of overseas industrial parks is a key component of the Belt and Road Initiative and an expected experimental way of promoting inclusive globalization by inventing new forms of cooperation between China and local host countries. Policy mobility, a classic theory within international political geography addressing the connection between local and global policies, has implications for overseas industrial parks development. In this paper, we argue that policies are not easily moved directly from one place to another; instead, policies are embedded due to the role of local actors in policy mobility. This article first provides an overview of seven China-Southeast Asia economic and trade cooperation zones identified by the Ministry of Commerce, and analyzes their key participants. It then discusses policy mobility by looking into the roles of revenue, land, and talent in developing these industrial parks. The paper finds that these parks face challenges, such as the complicated geographical environments of host countries, huge pressure from enterprise investment capital, the lack of overseas service platforms, and underdeveloped agglomeration economies. In the light of the current situation, policy suggestions for the future sustainable development of overseas industrial parks are put forward.  相似文献   
156.
Afghanistan is an important country for the Silk Road Economic Belt and the 21st Century Maritime Silk Road (the Belt and Road) proposed by China. Due to years of war, Afghanistan is not well-developed economically. However, Afghanistan has abundant mineral resources and unique geographical advantages that are of far-reaching significance for Chinese economic strategic development. To investigate the sustainability of the eco-economic system of Afghanistan, we completed a quantitative evaluation of the emergy of Afghanistan during the period 2008 to 2015 by establishing an indicator system based on an emergy analysis. Results showed that from 2008 to 2015, the total emergy used of Afghanistan increased from 5.56×1022 sej to 9.75×1022 sej, among which the proportion of non-renewable emergy was less than 25.7%. This indicates that local resources in Afghanistan have yet to be exploited and utilized effectively and that its economic development relied heavily on the input of external resources. Meanwhile, the Emergy Sustainability Index (ESI) of Afghanistan from 2008 to 2015 dropped from 3.00 to 0.72, the Environmental Loading Ratio (ELR) increased from 0.77 to 2.06, and the Emergy Yield Ratio (EYR) dropped from 2.31 to 1.49, reflecting the imbalanced utilization of resources and the low level of economic development in Afghanistan. As a result, the potential for sustainable development of Afghanistan is relatively great. Basic infrastructure construction and reasonable exploitation of natural resources are the urgent needs.  相似文献   
157.
基于1979—2015年ERA-Interim再分析资料,分析了夏季"丝绸之路"(the Silk Road,即SR)模态与东亚地区大气环流之间的联系,结果表明:在SR模态正异常年,200 hPa亚洲急流在东亚地区比较弯曲,在中国新疆和环渤海地区500 hPa上分别有一个高度脊和一个高度槽,在蒙古国、中国内蒙古以及日本以东500 hPa上有显著的位势高度正异常,风场异常与高度场配合较好。在对流层中低层的中国北方,有明显的下沉气流,在中国内蒙古、蒙古国以及日本以东,出现位涡负异常,而在朝鲜半岛附近,则有位涡正异常出现。中国环渤海地区降水偏少,而日本大部分地区降水偏多。在SR模态负异常年,200 hPa急流相对平直且更强,500 hPa的波列特征比正异常年更加显著,在中国内蒙古和蒙古国、朝鲜半岛、日本以东分别有"-、+、-"分布的位势高度场异常。与正异常年相比,位于东亚135°E附近的正异常中心变得显著,在该异常中心的西侧和东侧分别有上升和下沉异常气流,对应在朝鲜半岛和中国东北附近有较大的位涡负异常。在环渤海、朝鲜半岛南部和日本、日本以东洋面上,降水分别出现偏多、偏少和偏多现象。  相似文献   
158.
“ 中欧班列”陆路运输腹地范围测算与枢纽识别   总被引:4,自引:0,他引:4  
王姣娥  焦敬娟  景悦  马丽 《地理科学进展》2017,36(11):1332-1339
自“一带一路”战略实施以来,中国各地政府大力推进中欧国际班列运输,试图改变传统的对外贸易运输体系,强化提升新欧亚大陆桥运输作用。然而,设施联通、运输价格、货源及复杂的地缘政治环境等问题仍然是制约中欧班列发展的重要因素。为此,本文在分析“中欧班列”运营现状及存在问题基础上,提出实现其高频率常态运营的“轴-辐”运输组织模式。通过构建高、中、低三种运价方案,利用距离—经济成本分析法划分“中欧班列”主要出境口岸的经济腹地范围;并综合考虑各城市的铁路技术指标、集疏运能力和货源—成本等因素,从全国尺度识别出“中欧班列”组织的枢纽城市。  相似文献   
159.
It is widely recognized that rainfall over the Yangtze River valley (YRV) strengthens considerably during the decaying summer of El Niño, as demonstrated by the catastrophic flooding suffered in the summer of 1998. Nevertheless, the rainfall over the YRV in the summer of 2016 was much weaker than that in 1998, despite the intensity of the 2016 El Niño having been as strong as that in 1998. A thorough comparison of the YRV summer rainfall anomaly between 2016 and 1998 suggests that the difference was caused by the sub-seasonal variation in the YRV rainfall anomaly between these two years, principally in August. The precipitation anomaly was negative in August 2016——different to the positive anomaly of 1998. Further analysis suggests that the weaker YRV rainfall in August 2016 could be attributable to the distinct circulation anomalies over the midlatitudes. The intensified "Silk Road Pattern" and upper-tropospheric geopotential height over the Urals region, both at their strongest since 1980, resulted in an anticyclonic circulation anomaly over midlatitude East Asia with anomalous easterly flow over the middle-to-lower reaches of the YRV in the lower troposphere. This easterly flow reduced the climatological wind, weakened the water vapor transport, and induced the weaker YRV rainfall in August 2016, as compared to that in 1998. Given the unique sub-seasonal variation of the YRV rainfall in summer 2016, more attention should be paid to midlatitude circulation——besides the signal in the tropics——to further our understanding of the predictability and variation of YRV summer rainfall.  相似文献   
160.
利用1998—2009年北京观象台、大兴和丰台站气温小时观测资料,分析了五环路建设前后气温的变化以及气温变化的季节差异;利用2008—2009年北京观象台及其周边20km范围内站点的气温分钟资料,分析了观象台与其他台站气温资料的相关关系。结果表明,五环路建成后的5年比建设前5年年平均气温有0.98℃的升幅。五环路对观象台气温资料的影响存在季节性变化,气温升幅春季最小,秋季最大。北京观象台气温资料与周边台站气温资料存在较明显差异,气温绝对差平均值为0.57~1.92℃。  相似文献   
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