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1.
商末黄河中游气候环境的变化与社会变迁   总被引:21,自引:0,他引:21  
王晖  黄春长 《史学月刊》2002,2(1):13-18
新石器时代到商代黄河流域的气候属于温暖湿润期;商代后期气候出现厂干旱化,导致了古公亶父迁岐,文王迁程迁丰,帝乙帝辛时不断向南方发展;而商末的旱灾和饥荒是周武王克商的直接导火索,导致商周之际的改朝换代。商末气候环境的变迁对其时社会政治的影响极大。  相似文献   
2.
本文考证了渭南、华县之间的赤水河“桥上桥”的建造年代及形成原因。通过对有关历史资料深入研究,确证下桥始建于清初(1667年),上桥则建于清朝中叶(1832年)。赤水河中上游的过度垦殖和植被破坏带来的生态环境恶化造成了下游河床泥沙淤积,形成了地面悬河,原赤水桥为泥沙淹塞,失去功能,故不得不在桥上建桥。桥上桥的形成是当地生态环境变化的结果和标志。  相似文献   
3.
陈启虎 《攀登》2005,24(4):41-44
正确认识环保产业在我国国民经济发展中的作用和地位,有利于促进环保产业的健康可持续发展。本文从环保产业在国民经济发展中的功能定位出发,认为环保产业是重要的基础性产业,我国环保产业的发展有着广阔的市场需求,环保产业是我国经济发展中的新增长点。  相似文献   
4.
尹宏兵 《江汉考古》2005,(2):61-65,73
三峡地区与东部平原的不同地理环境,导致了峡区和平原地区的考古学文化的差异。古代人类对不同地理环境适应的结果,是反映在考古学文化中的环境因素。  相似文献   
5.
Crown Prince Mohammed bin Salman is moving across the international stage as the future King of Saudi Arabia. He has the support of his father, Saudi royals, and the oil income of his country. He also has 10‐year plan he agreed upon with the King called Vision 2030. The three components of the Vision are to diversify the oil‐based economy to include technology and tourism, to make the country the heart of Islam and Arab culture and to become the economic and geographic hub of Asia/Europe and Africa. His rise in power will depend upon his skill in expanding the religious tolerance of Saudi people, the current economic structure of the country, and the education of the youth. He is simultaneously addressing all these challenges in order to cement the country's future sustainability. Suggestions for enhancing his multifaceted impact on his country are provided.  相似文献   
6.
孙凌宇 《攀登》2009,28(2):72-76
随着技术创新的加速和经济全球化的日益扩展,变化已成为企业外部环境的基本特征,战略柔性的重要性日益凸显。本文详细分析了动态环境的涵义,探讨了动态环境中战略柔性的理论内涵,并提出了在动态环境下企业增强战略柔性的基本途径。  相似文献   
7.
姜运仓 《攀登》2009,28(2):81-85
在影响中国国家利益建构的各种变量中,国内环境所面临的机遇与挑战起着基础性的作用,其它变量的作用都要经过这一环节;国际环境与国际机制构成中国国家利益建构的舞台与背景;中国国际地位的提高及其对自己的定位则是中国国家利益建构中的内在因素和主观因素。  相似文献   
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9.
    
Substantial changes to the built environment, urbanisation patterns, and societal norms have contributed to limiting children's opportunities for being independently mobile. Several linear causal pathway models have been developed to understand the influences on children's independent mobility; however feedback loops between and within the various levels of influence cannot be modelled using such an approach. The purpose of this paper is to refine the interrelationships of factors related to children's independent mobility, taking into account earlier models, broader contextual factors, recent children's geographies literature, and feedback loops. Systems model components were informed by attributes known to influence children's independent mobility, related qualitative findings, and the development of a framework that could lend itself to multilevel modelling approaches. This systems model may provide a useful structure for identifying how best to develop and monitor interventions to halt the declining rates of children's independent mobility.  相似文献   
10.
    
Site selection processes whereby companies choose a location for an expansion or relocation have changed substantially over the past several decades. One key shift has been the emergence of collaboration among both individual economic developers and cooperation among the communities they represent. The rise in collaborative practices has also been increasingly reflected in the contemporary economic development literature outside the discipline of geography. The aim of this paper is to provide an overview of economic development studies of collaboration and then to suggest ways that geographers might use concepts from that scholarship to inform and extend the limited number of studies exploring site selection practices. The paper begins by offering a context for the emergence of collaboration trends by highlighting the ways that information asymmetry in site selection processes create a demand for greater collaboration among industry practitioners. It then turns to an overview of the burgeoning literature on collaboration that has evolved over the last decade in the interdisciplinary scholarship on economic development. Next, the paper shifts to a discussion of the ways that geographers might use the literature on collaboration to inform studies of site selection, specifically focusing on geographic scale and research on site selection consultants as possible areas for future investigation. The article concludes by arguing that studying collaboration in the context of geographies of site selection holds the potential for greater insights into the broader outcomes of economic development.  相似文献   
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