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41.
1985-2015年中国省际人口迁移网络特征   总被引:1,自引:0,他引:1  
朱孟珏  李芳 《地理科学进展》2017,36(11):1368-1379
随着中国城市经济的发展以及城镇化的快速推进,人口迁移的空间格局发生了重大变化。本文基于1985-2015年全国省际人口迁移矩阵数据,运用社会网络分析方法,探讨中国省际人口迁移网络的整体特征以及每个节点在网络中的地位作用。研究结论为:①省际人口迁移网络密度经历了1985-2000年的缓慢下降、2000-2015年持续上升的过程,与西北、西南和中部主要人口迁出地向东部经济发达地区的集中性迁移成为发展主流密切相关。②人口迁移网络的内向中心势明显大于外向中心势,说明人口迁入地相对集中,人口迁出地相对分散。③省际人口迁移网络可分为东北—华北人口联动区、中原—长三角人口联动区、中南—华南人口联动区、西南人口联动区、西北人口联动区5个子群。其中,中原—长三角人口联动区是群内和群间联系最紧密的区域;中南—华南人口联动区是全国人口累计迁移量最高的区域;东北—华北人口联动区内部联系较强,对外仅与西北人口联动区联系较强。④基于中心性分析以及核心—边缘结构划分,各省(市、区)对于人口迁移网络的贡献意义不同,广东、北京具有全局控制意义,江苏、陕西、四川、浙江基本处于核心节点序列,上海、天津、内蒙古、福建核心作用逐渐增强,河南、湖北、河北、新疆核心作用出现下降,全国人口迁移路径总体向北偏移。  相似文献   
42.
Mount Pinatubo volcano erupted in June 1991 in the main island of Luzon belonging to the Philippines archipelago. Huge economic losses and population exodus have followed. This major crisis has been relayed with other crises due to rain-fed lahars which have been supplied with eruption deposits. These lahars have occurred every year since 1991 during the rainy season. They will probably last until 2005. After a brief presentation of the Philippine official response system to disasters, this paper draws up a critical analysis of the different kinds of institutional and social responses deployed to manage the different crisis and post-crisis phases of this event. Based on three viewpoints: from population, media and other actors, this analysis attempts to point out the strengths and weaknesses of the official management system, especially by studying the efficiency and the range of the solutions taken. So, it appears that the management of the June 1991 main crisis (eruption) was a success. On the other hand, difficulties have occurred with lahars risk management. Indeed, these lahars have obliged the authorities to protect and relocate thousands of people. In spite of persistent problems, the management system (monitoring/warning/evacuation) of lahar crises improves year after year. Failures appear especially within the rehabilitation program (protection/rehousing). Many direct (lack of means, preparedness, coordination, dialog, etc.) and indirect (politico-administrative, socio-economic, cultural contexts) factors come together to lock the wheels of the institutional response system. They defer the socio-economic start of this vital northern Philippines area. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
43.
ABSTRACT

Coastal communities are part of the Australian identity but little is known about their characteristics and their long-term prosperity prospects. Increased migration to coastal areas and increased exposure to extreme climatic events indicates a need for social and economic data to inform socio-ecological systems planning. Here, we undertake a geo-spatial analysis to develop a typology of Australian coastal communities and assess relative vulnerability to climate-driven environmental change for a range of social and economic indicators. The aim of this study is to understand how the vulnerability of Australian coastal communities varies with geographic location or community size, and in comparison to other community types. Results show that both the population size and location of a coastal community matter and that coastal communities overall are more vulnerable on some socio-economic dimensions to climate-driven environmental change than their rural equivalents. However, results also demonstrate that the smallest coastal communities are strong in some important aspects of the human, social and financial domains, putting them in a good position to deal with some changes. Scale-appropriate and context-specific social policies are needed to address identified socio-economic vulnerabilities, supported by a range of formal and informal institutional structures, such as strategies to improve education and female workforce participation, and encourage participation in volunteering to increase human and social capital.  相似文献   
44.
随着我国国民核算体系向SNA体系的转变,使国民核算的生产范围扩大了,社会产品的内容更丰富了,社会产品分配的界限不同了,社会产品分配的结果也变化了。通过对社会产品内容的确定,分析了社会产品在各部门的分配情况,提出了如何用帐户法核算各部门的分配结果——各部门的最终收入。  相似文献   
45.
Support for a Freeze on nuclear weapons is greatest in the East with pockets of support in the Middle West and Pacific Coast States. Factors influencing the spatial pattern are Walker's innovativeness rankings, the number of peace/Freeze activist groups and the pattern of defense employment.  相似文献   
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代内公平、国际贸易与可持续发展   总被引:5,自引:0,他引:5  
现阶段,不同国家或区域之间商品交流的种类与数量日益增大。由于发达国家与发展中国家在国际贸易中所扮演的角色不同,因此,在等经济价值交换规律的作用下,发展中国家的环境状况逐渐恶化。文章通过构建开放经济的物质流模型,探讨了物质交换行为对系统内部的自然环境的影响,并对1987年日本的物质流动状况进行了案例研究。分析表明,发达国家的经济发展水平在很大程度上依赖于其它国家内部自然资源与环境的支撑作用。  相似文献   
49.
知识经济与传统的农业经济和工业经济显著不同,由它推动着的社会信息化及经济全球化所带来的地理发展效应,无论是在发展因素的加入上,还是在地域的建造上都愈来愈向着全息化的方向发展。与之相应,世界地理的研究范式,也应该向着更为开放、更为兼容化的方向改进。为此笔者提出全息景观论,并以韩国为例,以展示这种理论的科学解释价值。  相似文献   
50.
This study examines the spatial distribution and impact of nonroutine accidental releases of hazardous materials relative to the demographic composition of residents in nearby communities. First, atmospheric dispersion modeling methods are used to delineate the impact zones of worst‐case accidents in two New York counties over the last ten years. Next, using accidental reports for 1997, GIS and statistical operations are used at the census tract level of the two counties to determine whether these incidents disproportionately affected disadvantaged neighborhoods. The results suggest that the areas of high‐impact from accidental releases of hazardous materials are best characterized by a large proportion of families below the poverty line, Hispanics, and other minorities.  相似文献   
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