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James A. Tyner 《Singapore journal of tropical geography》1999,20(2):193-209
In the last three decades, there has been an increased "feminisation" of international migration within the Asian region. In part, the increased mobility of women migrant workers within Asia has resulted from the increased bureaucratic regulation of labour migration. This commodification of the migratory process, however, has placed women in significantly more vulnerable positions vis-´-vis their male counterparts. Comparatively little research, however, has examined the critical role of private recruitment agencies, and especially the use of the Internet, within the migratory process. In this paper, I examine the Web-based recruitment strategies of private recruitment agencies in Asia. Based on a qualitative analysis of 25 recruitment-related Web sites, I suggest that the commercialisation of migration serves an important "socialisation" process that contributes to the vulnerability and exploitation of female foreign domestic workers. 相似文献
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飞蝗Locusta migratoria (Linnaeus)系斑翅蝗科Oedipodidae飞蝗属Locusta Linnaeus洲际性农业重大害虫，在我国主要包括东亚飞蝗L.migratoria manilensis (Meyen)、亚洲飞蝗[WTBX]L.migratoria[WTBZ] (Linnaeus)和西藏飞蝗L.migratoria tibetensis Chen。掌控飞蝗灾害的地理空间分布并预测起潜在的适宜分布区，对于我国飞蝗灾害的综合防控具有重要意义。结合三种中国飞蝗灾害记录地理信息和生物环境环境因子参数，应用最大熵模型(MaxEnt) 和地理信息技术(GIS) ，在3 km×3 km尺度上对三种飞蝗灾害在中国的地理分布空间格局梯度、灾害风险概率和风险等级进行了模拟预测与分析，并对影响分布的关键生物气候环境因子进行了分析。结果显示，蝗灾害风险区的地理分布模拟结果与历史记录完全符合，ROC检验表明MaxEnt 模型预测可靠性极高。三种飞蝗东亚飞蝗、亚洲飞蝗和西藏飞蝗在中国的灾害风险区总面积依次分别为315.87×104 km2、395.80×104 km2和125.00×104 km2，分别占国土面积的33.43%、41.96% 和13.25%。东亚飞蝗和亚洲飞蝗的灾害风险区存在75.8×104 km2的空间重叠，主要分布于我国农牧交错区及以南区域。三种飞蝗灾害风险区的地理梯度与分布格局与中国三大自然地理区高度吻合，其地理分布格局表现出显著的经度和纬度空间梯度异质性。刀切法检测（Jackknife test）表明，三种飞蝗灾害的主导生物—气候影响因子的不同导致了其地理分布格局的显著差异，表明蝗灾爆发概率同时受到各自不同飞蝗物种对气候环境的适应性与地理空间隔离作用的共同制约。研究结果可为我国飞蝗灾害的跨界联合全程防控、区域联网监测联控和综合治理提供参考依据。 相似文献
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迁移八律与中国人口迁移 总被引：3，自引：0，他引：3
胡兆量 《云南地理环境研究》1994,6(1):45-53
中国人口迁移具有下列八个特征：１，提高生活质量是经济目的迁移的主要原因，非经济目的迁移违反经济规律时不能巩固；２，在城市化过程中，乡村迁往城市是主要迁移方向；３，整体男性迁移多，轻工劳务和婚姻迁移突出地区女性迁移多；４，独身青年迁移多；５，短距离迁移多，高素质人口迁移距离较长；６，迁移有圈层递补现象；７，强迁移方向必然带来较弱的迁移回流，当两地经济势能接近和递转时，回流加强；８，城市化过程中大城市迁入人口比重大，吸引迁移的范围广。可见，列文斯坦提出的人口迁移规律基本上适合中国的实际，中国人口迁移的实际又丰富了列文斯坦的人口迁移规律。 相似文献
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以三亚为例,基于对256位候鸟旅游移民的实地调研,采用因子分析及方差分析等方法,探讨了候鸟旅游移民迁移驱动力的结构、强度及群体差异。结果表明：1）三亚候鸟旅游移民经济收入和文化水平相对较高,但也存在显著的内部差异;2）三亚候鸟旅游移民迁移驱动力由风景环境、社会资本、社会象征、城市服务、生活方式、家庭氛围及健康养生等7个因子组成,其中,健康养生居得分最高,城市服务得分最低;3）与国外主要对“美好生活”的积极追求不同,三亚候鸟旅游移民多受年龄增长带来的健康问题所驱使;4）文章揭示了“旅游休闲—日常生活”这一动力连续体,反映了三亚候鸟旅游移民迁移驱动力的复杂性;5）不同性别、文化程度、年龄、旅居时间的三亚候鸟旅游移民迁移驱动力具有一定差异,尤其是不同文化程度及年龄,意味着收入水平、消费观念及健康状况的不同,对其驱动力影响较大,在社会资本方面区别显著。 相似文献
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Data recorded by the Italian Telemetered Seismic Network (ITSN) of the Istituto Nazionale di Geofisica (ING) have been widely used in recent years to image slab structures and to find evidence for active processes along the Italian Peninsula. However, the use of seismic data for geostructural purposes may be affected by the well-known trade-off between earthquake location and seismic-velocity parameters. Furthermore, the confidence ellipse predicted by standard procedures may be inadequate for the representation of the probable error of a computed localization. This paper evaluates the probable errors on the hypocentre determinations of the seismic events recorded by the ITSN, using a Monte Carlo method.
We compute synthetic arrival times using a 1-D velocity model appropriate as an average for the Italian area. The hypocentres used are all those recorded by the ITSN during the period January 1992 to March 1994 (1972 events). Station locations are those of the current ITSN configuration. The synthetic arrival times are perturbed with a Gaussian distribution of errors and input to ING's standard hypocentral location procedure, but using crustal velocities differing by 10 per cent from those used to generate them. Each simulation is repeated at least 30 times. Average absolute shifts of hypocentres are assessed in grid cells of linear dimension 33 km covering the whole Italian region.
For regions within the ITSN, shifts are typically 5–10 km in location and up to 20 km in depth. However, for offshore and coastal regions, they are much greater: 50 km or more in both location and depth (far exceeding the equivalent uncertainties quoted by ING bulletins). Possible consequences of this are highlighted by producing a cross-section of subcrustal hypocentres from the Adriatic to the Tyrrhenian Sea, where the large uncertainty in depth precludes any confident interpretation of dipping tectonic features. 相似文献
We compute synthetic arrival times using a 1-D velocity model appropriate as an average for the Italian area. The hypocentres used are all those recorded by the ITSN during the period January 1992 to March 1994 (1972 events). Station locations are those of the current ITSN configuration. The synthetic arrival times are perturbed with a Gaussian distribution of errors and input to ING's standard hypocentral location procedure, but using crustal velocities differing by 10 per cent from those used to generate them. Each simulation is repeated at least 30 times. Average absolute shifts of hypocentres are assessed in grid cells of linear dimension 33 km covering the whole Italian region.
For regions within the ITSN, shifts are typically 5–10 km in location and up to 20 km in depth. However, for offshore and coastal regions, they are much greater: 50 km or more in both location and depth (far exceeding the equivalent uncertainties quoted by ING bulletins). Possible consequences of this are highlighted by producing a cross-section of subcrustal hypocentres from the Adriatic to the Tyrrhenian Sea, where the large uncertainty in depth precludes any confident interpretation of dipping tectonic features. 相似文献
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鄱阳湖水利枢纽工程水位调控方案的探讨 总被引：5，自引：0，他引：5
利用历史水文资料、越冬候鸟分布调查资料及基础地理数据等, 从鄱阳湖形态的历史演变和鄱阳湖越冬候鸟生境保护的角度, 探讨鄱阳湖水利枢纽工程的水位调控方案。研究得到以下结论和建议:(1) 在维持鄱阳湖形态不变的情况下, 为有效保护越冬候鸟生境不受水利枢纽工程水位调控的影响, 工程调控水位不宜超过12 m, 但由于低水位运行不利于水利枢纽工程工程效益的发挥, 而高水位运行不利于越冬候鸟栖息地的保护, 为调和工程效益和候鸟保护之间的矛盾, 建议实施适当退田还湖, 以促进鄱阳湖水利枢纽工程的规划实施;(2) 根据地形、越冬候鸟分布范围、圩堤内居民点分布以及圩堤内土地利用现状, 提出了约640 km2实施退田还湖范围;(3) 以退田还湖为前提, 按照“调枯不调洪”原则, 提出鄱阳湖水利枢纽工程的水位调控方案, 为工程的推进和实施提供参考。 相似文献
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We provide a test of the hypothesis that most Palaearctic-African migratory passerines breeding to the east of Eastern Europe avoid crossing western deserts of Central Asia during autumn migration and make a detour through the steppes and semi-deserts north of the Caspian Sea. Trapping data at a migratory stopover and moon-watch observations in September 2003 in western Kazakhstan in a semi-desert location 375 km north of the Caspian Sea support this hypothesis. 相似文献
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近30 a来,意大利产业区成为西方学术界研究的热点与争论焦点。传统的意大利产业区模式主要强调中小企业为主的＂弹性专业化＂生产系统与本地社区的嵌入性。在全球化与知识经济的宏观背景下,意大利产业区正在经历一系列的以集团化、创新与国际化为主要特征的产业重组过程：产业区的组织结构开始由中小企业为主的＂弹性专业化＂生产系统向＂产... 相似文献
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Otomo A 《Population geography : a journal of the Association of Population Geographers of India》1983,5(1-2):44-59
This paper discloses, istly, the spatial mobility of Japanese women and its change mainly between 1970 and 1980, through comparison with the men's mobility, in respect of distance of movement, age patterns, and labor force status, using population census data. Secondly, the chief reasons for the migration of women by types of migratory flows are examined using the data derived from the survey on reasons for migration conducted in 1981 by the Land Agency of the Government of Japan. Results show that the spatial mobility of Japanese women is smaller than that of men in long distance movements but is almost the same in short distance moves, and that the age pattern of spatial mobility of the women is nearly the same between both distances of movement. Also, it is disclosed that the mobility of women not in the labor force is higher for the whole country but lower in metropolitan areas than that for men. The prime reason for the migration of women is employment, the as same as that for men for the whole nation, but this varies between the types of migratory flows. 相似文献
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《The Journal of geography》2012,111(9):525-540
Abstract This paper is concerned with examination of jet streams, their number, nature, energy relationships, fluctuating location, and steering effect upon extra-tropical cyclones. Jet streams are analyzed in the context of a series of waves, in the upper-level zonal westerlies, that vary in length and oscillate between high and low-index stages. Features of special significance are: (1) a jet stream need not be accompanied by a surface cyclonic system, but the latter presupposes presence of the former; (2) the cyclonic system is one of the two major energy sources in the scheme of mid-latitude circulation; and (3) the transfers of angular momentum, water vapor, heat, and energy required to balance the global budget are accomplished, in part, by migratory eddies associated with wave motions aloft. 相似文献
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广东湛江红树林国家级自然保护区位于中国大陆最南端的湛江市,分布有全国最大面积的红树林。红树林生态系统生物多样性丰富,非常适宜鸟类生存,而保护区地处西伯利亚-澳大利亚候鸟迁徒路线,每年都有大量候鸟在红树林区内栖息繁衍。如何保护这些珍贵鸟类及红树林栖息地是保护区的主要工作之一。介绍了湛江红树林保护区鸟类资源特点及变化情况,并提出了一些可行的保护措施。 相似文献
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L. Papa 《Geophysical Journal International》1983,75(3):659-667
Summary. A depth-integrated hydrodynamical model of the Ligurian Sea has shown the existence of a seiche motion of the basin with a 5.8 hr period. This result was obtained by using an open model boundary from Nice, France to Calvi, Corsica and an artificial solid boundary from Corsica to Elba and the Italian mainland. This seiche has been identified with a 5.8 hr period wave which was revealed in the sea-level variations at Genoa and Imperia. 相似文献
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Àngels Pascual-de-Sans 《Area》2004,36(4):348-357
The aim of this article is to explore a methodological approach relevant to the study of population mobility. The approach considers not only the whole migratory process and the sequence of connected movements, but also what happens between each of them. The study of mobility is considered inseparable from the study of passage, permanence and settlement. This paper establishes the interest in elaborating concepts that express the interaction between people and places, and how these interactions contribute to an understanding of migratory processes and of 'place histories'. In this sense, geographical identification (idiotopy) and place identification (idiotope) are put forward as useful concepts. 相似文献
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In Israel, a well-known avian migratory bottleneck, there is a temporal and geophysical divide in the flyways. The migration at Eilat, at the southern tip of Israel, is disjunct from the flyway in central and northern Israel. In order to elucidate the differences between the two flyways, we compared the data collected simultaneously at the Kfar Ruppin ringing station in northern Israel, and in the IBRCE Bird Sanctuary in Eilat at the southern tip of Israel. We chose the three most common species that are typical long distance, trans-Saharan, passerine migrants: Blackcap (Sylvia atricapilla), Lesser Whitethroat (Sylvia curruca) and Reed Warbler (Acrocephalus scirpaceus). At both ringing stations, the number of migrants recorded in spring was considerably greater than in autumn for all three species. Individuals from all species analysed in both passage seasons at Kfar Ruppin had longer wings than in Eilat, and in spring all three species were heavier in Kfar Ruppin. Our study is the first to show that there are biometric differences within Israel and stress the need to study the eastern migratory flyway of the Western Palaearctic in order to fully understand the intercontinental movements of the EurAsian migratory passerine populations. 相似文献
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青岛胶州湾湿地水鸟资源现状及保护对策 总被引：1，自引：0，他引：1
胶州湾是山东半岛面积最大的河口海湾型湿地,湿地总面积约3.7万hm2,由于其特殊的地理位置和丰富的湿地生物资源,成为亚太地区水鸟迁徙的重要停歇地和越冬地。目前胶州湾湿地鸟类有12目26科156种,其中包括许多全球濒危和国家级重点保护种类。鉴于目前胶州湾的不断萎缩及湿地生物多样性和生态环境的不断破坏现状,为保护湿地水鸟资源,恢复胶州湾良好的生态环境,应尽早建立湿地自然保护区,开展水鸟资源的保护和湿地环境生态改造,为亚太地区候鸟的顺利迁徙提供良好的栖息地,推动青岛市自然保护区建设事业。 相似文献
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"This article presents results from a longitudinal study using data from the Norwegian population register, combined with data from the 1970 and 1980 censuses. For two generations, those born in 1948 and 1958, successive migrations are considered and the effects of various sociodemographic characteristics on migratory behaviour are explored....Event-history analysis is used to examine the duration of stay at the place reached at age 22, and the effects of individual characteristics on this duration. Since a distinction is made between intra- and inter-regional migration, it has been possible to show that these effects vary significantly depending on whether we are dealing with short- or long-distance migration." 相似文献
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BARBARA PINI 《The Australian geographer》2003,34(2):211-222
This paper reports on a doctoral study which investigated why women are absent in positions of leadership within the Australian sugar industry's agri-political group CANE-GROWERS. Its purpose is to confront and unsettle the explanation that this is a result of 'the Italians' in the industry. The paper begins by highlighting the pervasiveness of this claim and the way in which it was so often presented during the research as a known and unproblematic truth. Following this, I draw on feminist post-structural theory to offer three challenges to the claim that it is because of 'the Italians' that men dominate decision-making positions in the sugar industry. These are: a singular Italian culture does not exist; constructions of being Italian are not fixed or absolute; and a range of possibilities exist for negotiating, resisting and transcending notions of what it means to be an Italian wife/woman/daughter. This discussion reveals the usefulness of feminist post-structural theory for avoiding monolithic and homogeneous constructions of identity. 相似文献
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改革开放后,中国社会出现了同乡同业集聚的现象,新化文印产业就是其中具有代表性的一类。对文印人员流出地“故乡”与流入地“他乡”进行考察,运用质性研究方法,探究了在文印产业发展过程中“故乡”与“他乡”所发生变化、承担的功能与相互联系。研究表明：文印产业对“故乡”与“他乡”的社会、经济文化等各方面影响巨大;“故乡”的功能体现在为文印产业的发展提供了人力资源、为从业人员提供了从业路径,及感情交流与回归的空间;“他乡”促进了产业的技术革新,形成了集聚效应并为从业人员提供了向上社会流动的空间;“故乡”与“他乡”是产业背后推动文印产业发展的虚实两只手,并通过文印产业与从业人员的社会关系及构建的文化紧密相连,形成了产业、空间、人口相互联系、动态循环的新化模式。 相似文献