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1.
An analysis of internal migration in two regions, or dukuh, of Yogyakarta Special Region, Indonesia, is presented. Three types of migration are identified, commuting, circular migration, and out-migration. The focus of the study is on the increase in commuting and circular migration that has occurred since the 1970s; its relationships with education, agricultural innovation, and improved transportation; and the importance of circular migration as a link between rural and urban areas.  相似文献   

2.
刘涛  张家瑞  曹广忠 《地理研究》2022,41(10):2680-2696
持续活跃的迁移流动不仅深刻改变着中国的人口分布格局,也已成为影响区域人口结构的关键因素。为量化估计人口流动对老龄化进程的影响,本研究构建了一个方法论框架,将人口流动的作用分解为规模效应和年龄结构效应,并从地级尺度分析中国人口流动对区域老龄化进程的作用,解读其空间规律和内在机制。总体而言,人口流动导致多数地区老龄化加深,仅有少数地区的老龄化得到缓解;人口流入对老龄化的降低作用和流出的提升作用并非绝对。人口流动的老龄化效应具有显著的空间分异和聚散特征:“胡焕庸线”是重要分界,人口大量流入的东部沿海城市群、内陆省会等区域性中心城市、西部多数地区降低作用突出,人口大量流出的长江中上游和淮河流域提升作用明显。规模效应在人口流动对老龄化及其空间格局的影响中发挥主导作用;按流入、流出分解后,结构效应的解释力得以体现。规模和结构效应在不同地区存在差异化的作用模式。最后开展了类型分析,并探讨了各类型区人口流动影响老龄化的特征和未来趋势。  相似文献   

3.
《Urban geography》2013,34(1):22-38
It is argued that the spatial patterns of place-ties collectively held by potential metropolitan-to-nonmetropolitan migrants are broader than those held by potential nonmetropol itan-to-metropol itan migrants. Consistent with this argu ment, it is hypothesized that metropolitan migration fields are asymmetrical , i.e., out-migration fields are more cosmopolitan than in-migration fields for the period 1965-1 970 within the United States. The hypothesis is accepted generally, and the asymmetry is found to be greatest for the largest metropolitan areas, some of which were also experiencing net out-migration during the period. It is concluded that the micro-level concept of place-ties and the macro-level concept of migration fields are important inputs to the understanding of population redistribution patterns.  相似文献   

4.
"This article examines union republic migration trends in the USSR between 1979 and 1987 and prospects for indigenous out-migration from rural areas in Central Asia. The study is based on migration data derived by the residual technique and migration data from the 1985 microcensus. Results indicate that a south-to-north and probably Russian-dominated migration trend emerged in the 1980s, one which marks an almost complete reversal from earlier periods, especially 1959-70. Although Central Asia continues to have low levels of indigenous out-migration, labor surpluses and relatively waning capital investment in Central Asia may change this situation."  相似文献   

5.
Sparsely populated areas in present-day North West Europe are almost automatically associated with demographic decline, in particular when studied on a local level. An image of an urn-like age pyramid, bulging near the top and with a slim base, presents itself to the observer. But it should not be forgotten that such a situation, with more deaths than births, is a long-term elTect of years and years of net out-migration. The analysis of geographic mobility thus becomes more important than fertility and mortality stud- ies. We want to understand how the age pyramid has become an urn.  相似文献   

6.
This paper indexes rural male out-migration and explains changing intensity patterns in Uttar Pradesh, India, since 1961. The sex ratio among non-migrants serves as an indicator of regional variations in rural out-migration. The paper highlights 2 population divergence zones in the underdeveloped Northern hilly and Eastern plain regions. The process of infrastructural development combined with cultural factors and inadequate employment opportunities seem to stimulate rural outmigration. Regional imbalance in economic development seems to be working as a suction economic system. The developed regions in India are utilizing the labor force of backward areas. The number of districts of high and moderately high rural male outmigration has increased, reflecting a wider gap between individual income and regional inequality. Unless the process is reversed in favor of rural areas, strategies for development will only work in capitalistic frameworks which serve the interests of developed regions.  相似文献   

7.
风暴洪水主要承灾体脆弱性分析——黄浦江案例   总被引:3,自引:2,他引:3  
脆弱性分析是自然灾害风险研究的热点问题之一。风暴洪水是上海黄浦江流域所面临的最主要自然灾害类型,历史上对该区域造成极为严重的灾害损失。通过多次灾后调查,结合前人研究成果,构建该区域7种主要承灾体经济损失脆弱性方程和人口脆弱性方程。基于前期黄浦江风暴洪水多情景危险性成果,开展实证研究,结果显示:经济损失和人口脆弱性分布自黄浦江上游地区向下游逐渐降低。最后,提出未来脆弱性研究中有待进一步完善和发展的工作。  相似文献   

8.
This article examines linkages between recent domestic out-migration from immigrant gateway metropolitan areas and nonmetropolitan migration gains, based on data of the 1990 census, 1996 Current Population Survey, and population estimates for the 1990–1996 period from the Bureau of Census. Our analysis of these data suggests that there is a mirror image of migration patterns between high immigration metropolitan area losses and nonmetropolitan area gains. This is especially evident in the West with the relationship between Los Angeles and San Francisco areas' losses on the one hand, and the region's nonmetropolitan gains on the other. While pre-elderly and elderly retirees have contributed to these nonmetropolitan gains, much of it is attributable to the destination choices of suburban-like populations—Whites with children, not college educated, and with lower incomes—that have been leaving high immigration metropolitan areas. This new, more dispersed form of “White flight” holds the potential for reinvigorating smaller, nonmetropolitan communities, but creating, as well, new demographic divisions across space.  相似文献   

9.
"This article presents newly-available migration data from the 1990 U.S. census to assess immigration and internal migration components as they affect state poverty populations. New immigrant waves are heavily focused on only a few 'port-of-entry' states. It is suggested that these immigrants have begun to impact upon internal migration into and out of these 'high immigration states', and have also altered the national system of internal migration patterns. This article addresses three questions: How do the magnitudes of poverty population out-migration from high immigration states compare with those of other states? Is this out-migration selective on particular social and demographic groups? Is immigration a significant determinant of internal migration of the poor population? The results of this analysis are consistent with the view that recent, focused immigration is associated with out-migration among a state's poor longer-term residents."  相似文献   

10.

This article examines linkages between recent domestic out-migration from immigrant gateway metropolitan areas and nonmetropolitan migration gains, based on data of the 1990 census, 1996 Current Population Survey, and population estimates for the 1990–1996 period from the Bureau of Census. Our analysis of these data suggests that there is a mirror image of migration patterns between high immigration metropolitan area losses and nonmetropolitan area gains. This is especially evident in the West with the relationship between Los Angeles and San Francisco areas' losses on the one hand, and the region's nonmetropolitan gains on the other. While pre-elderly and elderly retirees have contributed to these nonmetropolitan gains, much of it is attributable to the destination choices of suburban-like populations—Whites with children, not college educated, and with lower incomes—that have been leaving high immigration metropolitan areas. This new, more dispersed form of “White flight” holds the potential for reinvigorating smaller, nonmetropolitan communities, but creating, as well, new demographic divisions across space.  相似文献   

11.
中国省际人口迁移格局演变及其对城镇化发展的影响   总被引:11,自引:3,他引:8  
杨传开  宁越敏 《地理研究》2015,34(8):1492-1506
基于2000年和2010年人口普查数据,利用多种指标和方法研究了中国省际人口迁移的格局演变及其对城镇化的影响。研究发现:省际迁入和迁出人口在空间分布上均呈分散化态势,迁入迁出重心均向北向东偏移,迁入地由广东省“一枝独秀”向多极化演变,安徽、四川、河南、湖南成为新的四大迁出地。利用净迁移流构建的省际人口迁移网络,表现出紧凑化和均衡化趋势;迁移流仍然是从中西部地区指向东部地区,但新增加迁移流集中指向长三角、京津以及福建。综合考虑省际人口迁移强度和方向,可将全国31个地区划分为净流入型活跃区、平衡型活跃区、净流出型活跃区以及非活跃区四种类型。省际迁移改变了迁入地和迁出地的城乡人口结构,通过不同模式促进了城镇化率的提高和省际差异的缩小,对2000-2010年全国城镇化率增加的贡献占到了18.13%。  相似文献   

12.
四川省拐卖儿童犯罪的时空演变过程及影响因素分析   总被引:1,自引:1,他引:0  
拐卖儿童犯罪给受害者带来身心创伤、给家庭带来巨大悲痛和长期困扰,已成为社会和学界关注的焦点问题。该领域犯罪地理学视角的研究兴起较晚,且主要侧重宏观整体分析,当前亟需聚焦高发源地和重点人群作精细解析。为此,论文针对中国拐卖犯罪重灾源区四川省,综合运用数理统计、空间分析、文本分析、案例分析等方法探究四川省拐卖儿童犯罪的时空演变过程与影响因素。研究发现:① 数量上,被拐男童明显多于女童,被拐儿童主要来自乡村,虽呈现1~6岁和14~17岁的“双峰”型特征,但整体趋向低龄化。② 时间上,犯罪年际分布大致呈倒“V”型波动态势,高发期为1981—2000年;犯罪年内分布集中于夏半年,周内分布周末高发,日期分布每月1日的被拐儿童数量最多。③ 空间上,存在一个被拐高发区和多个被拐次高发区;县域尺度上的犯罪格局呈现“高—高”和“低—低”聚集;随着时间的变化,拐出热点区不断向南部和东部蔓延;宏观贩运路径上,向中东部地区分散拐入,华北和华南是重点拐入的“南北两汇”。④ 对1981—2000年犯罪高发期的原因解析发现,受教育水平与城乡收入差距是影响拐卖儿童犯罪的主导因素。  相似文献   

13.
Land surface emissivity is known to be affected by land cover, surface roughness, and soil moisture. In this study we used land surface emissivity data from National Aeronautics and Space Administration's Advanced Microwave Scanning Radiometer for Earth Observing Systems for 2003 to 2007 to detect areas of significant emissivity change and identify its potential causes. Data distribution of annual emissivity averages on a global scale revealed that the western coastlines of the continents, deserts, and the polar areas showed the lowest emissivity values, whereas the higher emissivity values were concentrated in large cities, heavily forested areas, and large mountain ranges. A two-tailed Z test was then used to identify regions that showed statistically significant changes at the 99 percent confidence interval. At the regional scale, three regions that showed statistically significant annual change values at the 99 percent confidence interval—the Iranian Plateau, the La Plata basin, and the Indus basin—were then isolated. An analysis of variance was then performed to determine whether the variability was due to phenomena across the region or within each region. In the La Plata River basin, areas of significant negative emissivity change (≤–0.0156) were noted, which are associated with deforestation, whereas the areas of significant emissivity gain (≥0.0165) were concentrated in floodplains. In the Indus basin and Iranian Plateau, the significant negative emissivity change was associated with variations in surface wetness. Using emissivity as an indicator of land surface properties can assist in more detailed analysis of changes on the surface of the earth.  相似文献   

14.
Located in the foothills of the Indian Himalaya, Rajaji National Park was established to protect and enhance the habitat of the Asian elephant (Elephas maximus) and tiger (Panthera tigris). In 2002 the Van Gujjars, indigenous forest pastoralists, were voluntarily resettled from the Chilla Range (an administrative unit of Rajaji National Park) to Gaindikhata, a nearby area where they were granted land for agriculture. In this study we used a variety of remote sensing approaches to identify changes in land cover associated with the resettlement. The methods comprise two main approaches. First, we used object-based image analysis (OBIA) to identify the pre-resettlement land cover classes of use areas (representing agricultural expansion and adjacent areas of grazing, and collection of fuelwood and fodder) and recovery areas (representing areas where settlements were removed, and the adjacent areas of resource use). Secondly, we used trend analysis to assess the gradual and abrupt changes in vegetation that took place in use and recovery areas. To conduct the trend analysis we used BFAST (Breaks For Additive Season and Trend), which separates seasonal variation from long-term trends, and identifies breaks that can be linked back to disturbances or land cover changes. We found that the OBIA classification yielded high average class accuracies, and we were able to make class distinctions that would have been difficult to make using a traditional pixel-based approach. Pre-resettlement, the recovery areas were classified as mixed forest and riparian vegetation. In contrast, the use areas were classified primarily as grass dominated, brush dominated, and plantation forest, and were located relatively far away from riparian areas. Following the resettlement, the trend analysis showed a sudden change in the seasonal variation of NDVI in areas converted to agriculture. Areas neighboring the new agricultural land experienced sudden decreases in NDVI, suggestive of disturbances, at a higher rate than the same land cover types elsewhere. At the same time, these neighboring areas experienced a gradual overall increase in NDVI which could be caused by an expansion of leafy invasive shrubs such as Lantana camara in areas heavily used for biomass collection. The recovery areas also experienced a gradual increase in NDVI as well as sudden breaks to this trend, but we lacked evidence to connect these changes to the resettlement. Our findings support the claim that the resettlement has shifted pressure from more ecologically valuable to less ecologically valuable land cover types, and suggest that to some degree resource use pressure has increased outside the park. The study employs a novel synthesis of OBIA and trend analysis that could be applied to land change studies more broadly.  相似文献   

15.
毒品犯罪是全球共同关注的犯罪问题,许多学者从不同的专业领域开展了大量研究。已有文献对毒品犯罪的成因进行分析,由于数据的局限性,较少从微观尺度对毒品犯罪热点的时空分布进行研究。论文以SZ市NH、DM街道内社区为例,基于毒品犯罪案件数据,利用探索性数据分析和时空扫描识别毒品犯罪时空热点分布,结合用地类型、动态人流量等数据定量分析毒品犯罪案件的时空分布影响因素。研究结果如下:① 毒品犯罪主要分布在商业发达地区和城中村地区,且城中村的毒品犯罪时空热点分布的起始时间较商业发达地区更早,影响范围也更大;② 毒品犯罪在不同用地类型分布是不均匀的,其中“住宿旅游娱乐”“商业百货批发零售”“餐饮经营服务品牌”3类用地类型与毒品犯罪具有高度相关性;③ 人流量高热区的面积占比与毒品犯罪的发生有一定的相关性,高热区面积占比大于5%或为0时,能够抑制毒品犯罪的发生;高热区面积占比在0~5%之间,能够促进毒品犯罪的发生。  相似文献   

16.
The aim of this Q methodology study was to identify perceptions of farmers and agricultural specialists toward agricultural water poverty concept and its causes in Marvdasht County, Iran. Seventy five participants completed the Q sort procedure. Data analysis identified seven types of perceptions toward agricultural water poverty: Management-adherents, Adaptive-adherents, Fatalists, Support-seekers, Farmer blamer Pessimists, Technocratic Realists and Optimists. The first four types of perceptions were dominated by farmers and the last three by agricultural specialists. These different perspectives indicated that various individuals think differently about the nature, causes, effects and permanency of agricultural water poverty. Understanding the multiple meaning systems of agricultural water poverty for decision and policy makers will be critical as they may provide the basis for the development of more appropriate strategies to mitigate water poverty in agricultural sector.  相似文献   

17.
An analysis is made of the information-communication network deployment into the center–periphery systems, heterochronous formations and network areas which are derivative territorial structures with respect to the initial network. By using an example of changes in the network position of a number of administrative centers of Asian Russia for 200 years, it is shown that the partitioning of settlements into the information-communication center and the periphery is relatively stable across time. An assessment is made of the transformation of peripheral settlements having regard to the relationship of the status and topological centrality as well as infocommunication–geographical location. The study revealed homochronous, rhythmic- and arrhythmic-heterochronous networks. By analyzing, for different times, the distribution dynamics of elementary postal networks of Asian Russia between the center and the near, middle and far periphery, it was possible to determine a number of characteristic features of the deployment process. It is established that the postal-network areas of the region produce a linear territorial entity. A comparison of the regionalization schemes from different times provided a means of assessing the transformation mechanism of the territorial structure that manifests itself in an extensive, unevenly differently directed deployment of the network with a topological separation between settlements, an increase in their network inequality, and with the consolidation of the linear structure.  相似文献   

18.
人文因子在荒漠化中的作用   总被引:16,自引:3,他引:13  
董玉祥 《中国沙漠》1992,12(1):16-26
分析四个典型区荒漠化的形成条件、历史过程与现代过程,从而阐明人文因子在荒漠化中的作用,得出荒漠化历史过程是自然过程、现代过程是人为加速过程的结论,其中荒漠化现代过程中人文因子的作用占60%。  相似文献   

19.
针对中国东南沿海部分地区未通过大规模人口迁移而实现转型的就地城镇化现象,选择3个就地城镇化发达地区,在问卷调查数据的支撑下,构建了“乡村拉力一城市拉力”(“双拉力”)概念模型,探讨乡村劳动力迁移行为、迁移意愿及其城镇化效应。结果显示,居民迁移行为不太频繁,且多数为就地就近的近距离迁移;同时迁移意愿不够强烈,并且倾向于近...  相似文献   

20.
It is widely accepted that environmental change can influence human migration. In particular, the environment plays a role in migration processes in drylands, in which environmental change—including increasing variability of rainfall, increasing frequency of droughts, chronic water shortage, and land degradation—can heavily influence migration. However, systematic large-scale studies of the relationship between environmental factors and human migration are rare, and a global, consistent picture of environmental drivers of migration is lacking. In this study, we sought to fill this gap by analysing spatial patterns of environmental drivers of migration in drylands by performing a cluster analysis on spatially explicit global data. In this analysis, we focused explicitly on precipitation, aridity, drought, land degradation, soil constraints, and availability of cropland and pastures as potential environmental drivers of migration in drylands. In addition, we linked the identified clusters to two observed hotspots of out-migration—Burkina Faso and Northeast Brazil—to gauge the cluster results. Our results show that environmental drivers can be grouped into eight distinct clusters, and we identified the most severe environmental constraints for each cluster. These results suggest that out-migration—both in absolute and relative terms—occurs most frequently in a cluster that is constrained primarily by land degradation rather than water availability.  相似文献   

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