当代国际移民创业研究进展

移民创业活动是经济地理学研究中一个重要主题。创业是一种经济活动,但不同群体的创业活动蕴含着不同文化内涵和行为选择。移民创业的研究是解读移民群体社会与文化形成的一个关键的维度。移民群体具有明显的边界,其内部的空间秩序、社会网络、族裔文化以及共同的身份认同都是值得探讨话题,因此学界对移民创业活动给予了持续的关注。移民活动日益频繁,所涉及的行业地域日益扩大,对移民创业群体的研究有利于促进区域经济发展、了解全球政治网络,沟通地理学与社会学和经济学的研究融合,是经济地理学研究中值得关注的问题。本文基于Citespace软件,运用文献分析法,从国际移民创业概念内涵阐述、研究动态、研究前沿及演变、未来研究可能四个方面出发,阐述移民创业研究的历史脉络及进展。研究发现美国和英国在移民创业中占有重要地位。区域创业环境是研究者们主要关注的话题,与创业联系最为紧密的是绩效（0.28）、自雇佣（0.17）和组织（0.17）等关键词研究。全球化趋势不可逆转,跨国主义日趋强盛,未来关于移民及移民创业的研究大有可期。     

当代国际人口迁移的新形势

战后以来,国际人口迁移规模显著扩大,由发展中国家流向发达国家成为当代国际人口迁移的主流,1950～2000年间,由前者流向后者的净移民共达5800余万人,占同期内后者人口总增量的16%,但占前者自然增量的比重则不足2%。相对于本国自然增长,受移民迁入影响较大的有两类国家：（1）以往人口较少者,如西亚诸石油输出国;（2）自然增长率极低者,如西欧诸国。     

The geography of highly skilled international migration

"The present paper provides a research review of recent literature on international migration by the highly skilled. Its principal aim is to identify the themes which are being discussed, and suggest where research into the subject might best proceed.... [The authors outline] the two most important perspectives in extant research, economic and socio-cultural, [and review] what is known about the geography of migration by the highly skilled.... The paper proposes...a reconceptualisation of migration by the highly skilled as one element in the international movement of expertise."     

环境移民国际研究态势的文献计量评价

随着人口增加和环境压力日益增大,环境移民问题已成为生态、环境以及人口学方面的研究热点。以SCIE和SSCI数据库研究论文为数据源,利用Thomson Data Analyzer(TDA)和UCINET软件对其进行数据挖掘和定量分析。结果表明:相关研究的发文量整体呈稳态增长趋势;美国及其主要机构在该领域处于领先地位。在国家和机构层面,中国及中国科学院发文量较多,且近年来研究较为活跃,但研究水平、影响力有待提高;美国、德国、英国在国际合作研究中占有重要位置,中国及其研究机构与其他国家和机构的合作研究关系较弱;研究主题主要关注生态保护、扶贫性移民、移民迁出地和安置区、移民社会学及其政策等方面。     

Dilemmas in international migration: a global perspective

This paper addresses the migration situation and the increasingly passionate public debate that is a result of the presence of aliens in a state's territory. Foreign workers provide the labor necessary to maintain an industrial climate during times of critical labor scarcities. Due to this condition of selected labor shortages, labor importers become increasingly dependent on a constant supply of foreign labor, while the labor supply becomes more independent of the host's actual labor needs. The reality of permanence, especially with second generation migrants, creates social and cultural dilemmas--migrants become more assertive of their economic rights, and natives react negatively to the economic competition. International migration is a process structurally central both to the sending and to the receiving societies. The process has accomplished at least one important goal: it has significantly improved the economy of many families whose members have emigrated. What is needed is better attention to timing, structure, and the consequences of migration in the context of a class analysis that addresses the phenomenon of labor migration in terms of class struggle by migrants, capital, and domestic labor. Home community remains a primary reference point and a principal determinant of behavior for the emigrant. Societies are still quite inept, not only at predicting migration flows and their impacts on receiving societies, but also in understanding the linkages between emigration, return, and the development of the countries of worker origin.     

1990—2015年亚洲内部人口迁移格局及影响因素

把握亚洲内部跨国/地区人口迁移规律,有助于新时期中国制定合理的国际移民政策,推动“一带一路”倡议迈向高质量发展。本文基于1990—2015年国际双边移民流量数据,运用社会网络分析和空间滤波面板负二项引力模型,阐明亚洲内部跨国/地区人口迁移的时空格局与驱动因素。研究发现：① 1990—2000年亚洲主要迁移流集中在西亚、南亚和东南亚各区域内部,且大多发生在邻国之间,2000—2015年出现多条横跨上述三大区域的大规模迁移流;② 人口迁移网络强度相对较低,联系紧密程度先升后降;③ 政治不稳定与战乱冲突是人口迁移的重要推动力,经济发展水平差异和国民收入差异是重要驱动力,多维邻近因素（经济邻近和文化邻近）也起到一定的推动作用;④ 25年间,经济差异的影响先增后减;政治不稳定一直是人口迁移的主要影响因素,且对人口迁出的影响更大;进出口贸易发展在部分时期积极促进人口流动,留学吸引力影响呈波动趋势;⑤ 非经济和结构性力量在亚洲内部跨国/地区人口迁移过程中起到决定性作用。     

“一带一路”沿线国家或地区间人口迁移的空间格局及其演化特征

基于联合国人口司国际移民存量数据,借助社会网络分析等方法,对1990—2017年“一带一路”沿线国家或地区间人口迁移的空间格局及其演化特征进行研究。主要结论如下：（1）沿线国家或地区间人口迁移规模扩大,增速加快,迁移路径更加多样化;（2）沿线国家或地区间人口迁移空间分布呈集中性特征,迁移目的地集中于俄罗斯、印度、沙特阿拉伯等国,来源地集中于俄罗斯、印度以及亚洲大部分国家;（3）沿线国家或地区间人口迁移网络具有临近效应、国际地缘政治效应和路径依赖效应;（4）沿线国家或地区间人口迁移网络具有明显的社团结构特征,可分为独联体社团、中东欧社团、中东社团、伊拉克-伊朗-阿富汗社团、北非-海湾-南亚-东南亚社团、中国内部社团。     

Emigration,return, immigration: a review and evaluation of Greece's postwar experience of international migration

"This paper offers a review and evaluation of the Greek experience of international migration.... The analysis is based partly on available published data, and partly on qualitative appraisals. Three major international migration phases are analysed--emigration, return migration and immigration--and the main socio-economic and cultural effects of these migration trends are discussed. The paper pays particular attention to the recent mass immigration movements, noting their heterogeneity...and describing their impact on the Greek labour market. The article concludes with some comments on the difficulties of formulating a Greek migration policy in the light of the country's location, open borders and internationalized economy."     

黄河口不同粒度泥沙沉积与扩散分析

本文采集和收集大量黄河三角洲沉积物剖面和钻孔泥沙粒度资料以及黄河口来沙粒度组成数据,定量研究了黄河口泥沙的沉积与扩散特征.结果 显示黄河口来沙以粉砂为主,黏土次之,砂最少,年均中值粒径无长期变化趋势.黄河三角洲平原相泥沙与来沙的黏土、粉砂和砂含量无显著差异;前缘相泥沙比来沙的黏土含量较低,砂含量较高;前三角洲相泥沙比来...     

Questions of migration and belonging: understandings of migration under neoliberalism in Ecuador

This paper explores alternative understandings and experiences of migration under neoliberalism in Ecuador. Through the case study, the study examines migrants' multiple motivations for mobility and their ambivalence toward the process. Insights from the transnational migration literature were drawn in order to think through the implications of an increasingly contradictory context of economic modernization and its impact upon the sense of possibilities and belonging of migrants. In-depth interviews with urban-destined migrants in Ecuador were drawn to argue that mobility produces ambivalent development subjects. This argument is developed in three sections. First, the paper centers on the epistemological and theoretical basis for the relevance of migrant narratives in extending theorizations of migration. Second, in-depth interviews with migrants to Quito are drawn to explore migrants' sense of belonging and regional affiliation, identity formation through migration, and experiences of alienation and disruption in their lives. Lastly, this paper concludes with a retheorization of the role of migration places in the migrant identity construction.     

长江口北支湿地分类及生境特征

长江口北支湿地可以划分为海岸潮滩湿地生境、河口湿地生境和人工湿地生境3大类,生境类型丰富。分析了每类湿地生境的特征,最后指出由于人类的高强度干扰,生境破碎化严重,生物多样性降低,湿地生态服务功能减弱。     

Pendulum population migration and the formation of settlement systems

Systems of circular migration existing in the USSR are described. The role that such migration plays in linking settlement systems is noted, and the influence of city size on migration is discussed.     

Geography and migration policies: the Indian experience

This paper attempts to examine the differences in sex preference and its impact on fertility behavior among various age groups in the State of Haryana. In India, male children have greater utility over females because of religious, social and economic reasons. Various studies have established the fact that there is a prevalence of sex preference and a marked relationship between son preference and family size. This leads to increased fertility, and ultimately towards population growth rate. Data were collected from the National Family Health Survey report in 1993. The intensity of sex preference on fertility was computed on the basis of contraception method. Moreover, detailed analysis was carried out on the basis of desired additional children and their sex ratio. This study also presents an examination of the Indian system, family planning measures, sex ratio of desired additional children taken as a basis for the measurement of overall effect of sex preference on fertility.     

Elongation and migration of sand dunes

Two distinct processes are known to act on dynamic dunes, the process of migration by erosion on the windward side and deposition on the lee side, typical for transverse dunes, and the process of elongation typical for linear dunes. These two processes are determined by wind direction relative to the dune alignment. This article reviews the assertion that linear dunes experience lateral displacement in addition to elongation. Fieldwork on vegetated linear dunes (VLDs) and GIS work on seif dunes indicates no lateral migration for these dunes. Linear dunes can shift laterally only when a slip face, formed on the lee side, reaches the plinth of the dune. The winds from both sides of the seif dune are never symmetric; usually winds from one direction are more dominant and effective. The outcome is the formation of peaks and saddles along the dune. The strongest winds create a slip face on the lee side of the peak segments of the dune, oblique to the dune alignment, which reaches the base of the dune and displaces the peak downwind along the dune alignment. The internal structure of the seif dune is formed mostly by this dominant wind direction and gives the impression that the dune has shifted laterally. On the other hand, there are cases in which the wind directions relative to dune alignment fall between those of transverse and seif dunes. In such cases, both processes act on the dune, which subsequently experiences migration as well as elongation.     

国际干旱区研究发展态势简析

基于SCI-E的国际干旱区研究科学计量指标明显上升,灰色预测显示未来仍将保持较大幅度的上升态势；美国是国际干旱区研究的科学活动中心,国际产出力指标居前的机构绝大多数出自美国；中国是国际干旱区研究产出力排名仅次于美国的第二大国；中国科学院是国际干旱区研究连续八年排名第一、产出力最高的科研机构；国际干旱区研究领域已经形成结构稳固、特征显著的核心支撑学科群。     

创新地理学——一门新兴的地理学分支学科

知识经济时代，创新成为人类社会，经济，政治活动的核心，在这种情况下，传统的地理学正受着来自学科自身的来自实践需要的双重挑战，以人地系统为研究对象的地理学，该如何适应这一变化并作出创造性选择呢？文章用唯物辨证法的观点，对这一问题进行了思索，并适时地提出了创新地理学这一新概念，阐述了创新地理学的产生背景，研究意义，研究对象及其内容。     

Geologic and societal factors affecting the international oceanic transport of aggregate

Crushed stone and sand and gravel are the two main sources of natural aggregate, and together comprise approximately half the volume and tonnage of mined material in the United States. Natural aggregate is a bulky, heavy material without special or unique properties, and it is commonly used near its source of production to minimize haulage cost. However, remoteness is no longer an absolute disqualifier for the production of aggregate. Today interstate aggregate routinely is shipped hundreds of kilometers by rail and barge. In addition, during 1992, the United States imported 1,317,000 metric tons of aggregate from Canada and 1,531,000 metric tons from Mexico. A number of ports on the Atlantic Coast and Gulf Coast of the United States receive imports of crushed stone from foreign sources for transport to various parts of the eastern United States. These areas either lack adequate supplies of aggregate or are augmenting their supplies because they have difficulties meeting current demand. These difficulties may include poor stone quality, environmental permitting problems, or transportation. Certain societal and geologic conditions of New York City and Philadelphia along the Atlantic Coast, and Tampa and New Orleans along the Gulf Coast, are discussed to demonstrate the different combinations of issues that contribute to the economic viability of importing crushed stone.