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本文根据野外考察和室内研究,总结了海拉尔盆地盐湖的概况、盐类矿物组成、水化学成分和盐湖的形成自然环境;探讨碳酸盐型盐湖和形成条件和天然碱的成因机理.  相似文献   

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First, central to our analysis is the argument that human movement within and across borders fundamentally challenges the view of geopolitics based upon fixed territorial states, inter-state relations, national identities and citizenship; indeed the whole idea of "national geographic". Using the examples of the Karen and Shan peoples, we explore the processes and patterns of forced relocation, displacement and migration in the border regions of Myanmar and Thailand. Our main concern is with forced displacement as a result of political and ethnic conflict; specifically, how the Burmese military regime's desire for "national unity" within Myanmar's "national space" has influenced the militarily inspired displacements of hundreds of thousands of villagers and civilians within the border zones inhabited mostly by so-called "national minorities". We examine the particular problems of the so-called "internally displaced persons" within "national" boundaries compared with the "refugees" and "undocumented migrants" who make it across "international" space into Thailand. We illustrate the ways displaced people are represented by state agencies and the media as "threats" and "transgressors". We consider some of the "long term" aspects of the displacement problem along the Myanmar-Thai border and the vital contribution geographers can make to the study of displacement.  相似文献   

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基于A-T-R的旅游小城镇分类、评价与发展模式研究   总被引:1,自引:0,他引:1  
陶慧  刘家明  朱鹤  李玏  王磊 《地理科学》2015,35(5):529-536
在科学界定旅游小城镇基础上,梳理旅游小城镇的分类标准,确立一类基于核心吸引物(A)—小镇(T)—乡村环境(R)的新分类方法,将旅游小城镇分为AT一体、AT分离、A+T+R联动与ATR创意再造4种类型。结合旅游小城镇发展中的实际状态,依据A、T、R三类初始条件不同组合情况提炼出六大旅游小城镇的发展模式,为旅游小城镇深层次研究提供参考和依据,进一步推动旅游小城镇的健康发展。  相似文献   

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在实际调查基础上,利用遥感和地理信息系统技术,分析伊洛河流域伊河上游地区气候和土地利用变化对径流变化的影响。结果显示,在研究区域中,林地面积最大,1987-2008年,林地、库塘和建设用地面积持续增加,草地、河流和未利用地面积持续减少,耕地面积则先增加后减少。20世纪80年代以来,土地利用变化在不同阶段都使得年平均径流量减小;80-90年代,气候变化使得年平均径流量减小,而90年代到2000年以后,气候变化使得年平均径流量增加,这与90年代年平均降水量减少,而2000年以后年平均降水量增加密切相关。  相似文献   

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库木库里盆地盐湖形成自然环境   总被引:4,自引:0,他引:4       下载免费PDF全文
根据野外考察和室内研究资料 ,总结了库木库里盆地盐湖分布 ,卤水化学成分 ,盐类矿物组成 ,盐湖沉积特征 ,盐湖地质地理背景和盐湖形成演化自然环境  相似文献   

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晚第四纪科尔沁沙地干湿变化的黄土记录   总被引:5,自引:2,他引:3  
利用光释光(OSL)定年技术对科尔沁沙地南缘的典型黄土剖面进行了测年,结合两个剖面的磁化率、粒度、有机质含量等气候替代性指标,对沙地古气候及环境变化过程进行了分析。结果表明,晚第四纪科尔沁沙地的古气候经历了万年-千年时间尺度的多次干湿变化,特别是在146.96 ka BP前后、141.98 ka BP左右和107.06 ka BP前后发生过重大转变;相应地,沙地地表植被也经历了干冷多风条件下的干草原、荒漠草原和温暖湿润或温凉稍湿气候条件下的森林草原、疏林草原的多次变化。科尔沁沙地古气候的干湿变化可能是晚第四纪东亚冬、夏季风强弱变化的反映。  相似文献   

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Abstract

Although blacks constitute the largest ethnic minority in the United States, historically they have either been largely omitted from geographic literature or else portrayed in less than a humanistic manner. However, beginning about 1965 a change took place in geography regarding its interest and treatment of black Americans. Within the last eight or nine years the geography of black America has blossomed into a full-fledged subfield of geography. In all, over 200 theses, dissertations and published works have been produced by geographers during this period. Moreover, a sharp shift in subject emphasis has occurred. Prior to 1965, what little geographic literature there was dealt mostly with rural or regional studies. Now the emphasis is, at long last, upon urban black American where over eighty percent of blacks reside.  相似文献   

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The importance of commemorative place-naming has been the focus of numerous studies that explore the relationship between memory and political representation. Few studies, however, have systematically examined regional geographical patterns of racial minorities in the United States. Using a variety of Internet-based mapping tools, I have collected a data set on the regional variation of the commemoration of thirty famous African-Americans (fifteen men and fifteen women). The research presented here explores how there are regional characteristics associated with where African-Americans are commemorated, particularly pertaining to cities. I also explore the geographic dispersal of these commemorations and whether there is a gender bias in the process of commemoration. Additionally, I focus on the duality of commemorations as an index of both African-American and the dominant white power structures.  相似文献   

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For over a thousand years many settlements in Korea forbid the digging of water‐wells. This custom can be explained using geomancy, which personifies local landscapes or names them after animate or inanimate objects. In ‘sailing boat’ landscapes the digging of water‐wells was prohibited because this was viewed as analogous to making a hole in the bottom of a boat, which would thus bring misfortune to local residents. Based on this geomantic reasoning, people considered the custom of forbidding well digging to be an integral part of the art of geomancy, with its origin in a geomantic belief system. My earlier research sustained this explanation but this paper, which is based on two recent instances of field work, rejects the established view on the custom. The aim of this paper is to critically re‐examine this established view and suggests a new idea that the folk custom of prohibiting well digging in Korea was not originally derived from geomancy, but was conceived from a non‐geomantic indigenous Korean idea and have become linked to geomancy through the enforcement process of practicing the custom in traditional Korean society.  相似文献   

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长江三角洲城市群空间效率测度研究   总被引:4,自引:4,他引:0  
崔大树  张晓亚 《地理科学》2016,36(3):393-400
以长江三角洲城市群为例,构建空间效率的指标体系,运用DEA模型测度了1994~2013年长江三角洲城市群的空间效率及2005年、2009年和2013年长三角城市群各地级市的空间效率。基于ESDA空间分析平台,运用局部自相关模型对长三角城市群空间效率空间关联格局进行分析。对长三角城市群空间效率的评价分析发现,阶段性演变过程呈“W”型波动并在波动中上升的特征。空间效率有效的城市数量在逐渐增加的同时空间分异明显,但城市群内个体城市的空间效率差距在不断缩小。聚类特征表现出空间效率与城市规模、行政等级及区位优势等存在一定相关性,空间效率分布与要素集聚程度高度相关。长三角城市群的空间效率表现为明显的非均衡趋势,空间分异的集聚程度加剧。  相似文献   

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