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1.
This paper investigates the settlement patterns of the foreign population across the Spanish provinces over the period 2000–2009 and identifies the key determinants of these patterns. To this end, the paper determines the spatial distribution of foreign residents and, based on it, incorporates explanatory variables into a model designed to understand settlement patterns. After addressing the issue of spatial dependence, the model is estimated at both the aggregate level and for major areas of origin. The results reveal that social networks and economic factors, such as unemployment and per capita income in the hosting provinces, play a key role in explaining foreigners' settlement patterns in Spain. Significant differences exist, however, when areas of origin are allowed for. 相似文献
2.
Immigration settlement patterns are examined within a pooled cross-section time-series framework. Trends in settlement patterns from 1970 to 1979 differentiate the immigration streams from various source areas. Certain “new'’immigrants show an increasing propensity to concentrate, while immigrants from traditional source areas deconcentrate in some cases. The analysis suggests that immigration is a dynamic process with characteristics and determinants that change over time. 相似文献
3.
Zelinsky and Lee recently unveiled a model of the sociospatial process of immigrant settlement designed to augment and possibly supplant the well-known theories of assimilation and pluralism. Although in some ways new, their work continues a tradition in social science that treats the settlement geography of immigrants as a measure of their more general fit into American society. The authors question the prevailing assumption that immigrant settlement patterns represent a barometer of their adaptation, or lack thereof, to a host society. This critique of the concepts of assimilation, pluralism and Zelinsky and Lee's alternative "heterolocal" model of immigrant settlement pivots around the issues of spatial scale and race. The authors argue that the contestations over immigration and how well immigrants fit into society are increasingly constructed at the regional scale. The authors also assert that questions race infuse almost all aspects of these debates. The transformation of America's largest city-regions into places of non-White immigrants, and the shifting political balance of power to states like California through immigration-driven reapportionment, are touchstones for anti-immigration initiatives and associated local and national debate. Fear of racial regional changes underpins an increasingly powerful response to immigration. The reactions elicited by these settlement geographies fall under the heading the authors call the "territorial politics of immigration". 相似文献
4.
William Norton 《The Professional geographer》1978,30(2):128-134
Relationships between process and form are complex. Historical geographers concerned with the evolution of form may profitably investigate such relationships by analyzing both real processes and various counterfactual processes. Simulation is an appropriate method. For Southern Ontario two dissimilar settlement processes are used to generate settlement forms during the period 1782 to 1851. The resulting forms are initially different, but they converge through time and by 1851 have become similar. Different processes can generate similar forms although form evolution is not similar. 相似文献
5.
无定河流域全新世中期人类聚落选址的空间分析及地貌环境意义 总被引：1，自引：1，他引：0
以无定河流域的数字高程模型为主要研究对象,利用地理信息系统软件进行空间分析,与陕西北部无定河流域龙山时期遗址的分布位置叠置和聚类分析,讨论聚落选址与地貌类型、距河流水平距离、河网等级等6个地形地貌因子之间的关系。结果发现,全新世中期无定河流域人类在聚落选址时,对水文条件、地貌和地面坡度条件有较强的倾向性,而对地面朝向无明显倾向性。选址时选择地形地貌影响因子的优先顺序为:地貌类型、遗址距河流距离、遗址处地面坡度、遗址处河流等级、遗址处地面朝向。 相似文献
6.
《The Professional geographer》2013,65(2):128-134
Relationships between process and form are complex. Historical geographers concerned with the evolution of form may profitably investigate such relationships by analyzing both real processes and various counterfactual processes. Simulation is an appropriate method. For Southern Ontario two dissimilar settlement processes are used to generate settlement forms during the period 1782 to 1851. The resulting forms are initially different, but they converge through time and by 1851 have become similar. Different processes can generate similar forms although form evolution is not similar. 相似文献
7.
The thaw settlement of pipeline foundation soils in response to the operation of the first China-Russia Crude Oil Pipeline along the eastern flank of the northern Da Xing'anling Mountains in Northeast China was simulated in a physical model test(with a similitude ratio of 1/73) in a geotechnical centrifuge. Two pipes of a supported and an unsupported section were evaluated over a testing period for simulating 20 years of actual pipeline operation with seasonal cyclically changing oil and ambient temperatures. The results show that pipe settlement of the supported pipe was 45% of settlement of the unsupported pipe. Settlement for the unsupported section was approximately 35% of the thaw bulb depth below the initial pipe elevation, only 30% of that for the supported pipe due to the influence of the supports. The final thaw bulbs extended approximately 3.6 and 1.6 times of the pipe diameter below the unsupported and supported pipe bottom elevations, respectively. The sandbag supports kept frozen during the test period because of cooling effect of the thermosyphons. The maximum bending stress induced over the 20 m span length from bearing of the full cover over the pipe would be equivalent to40% specified minimum yield strength(SMYS). Potential buckling of the pipe should be considered as the ground thaws.This study also offers important data for calibration and validation of numerical simulation models. 相似文献
8.
基于DPSIRM模型的社区人居环境安全空间分异——以大连市为例 总被引：4，自引：1，他引：3
以DPSIRM因果关系模型拟定指标体系,运用模糊层次分析法和综合比较法赋权并量化计算,基于地理信息系统空间分析方法,对大连社区人居环境状况和全空间分异格局进行研究,结果表明:大连市社区人居环境安全单元分为五个类别,即社区人居环境安全评价很差单元、社区人居环境安全评价较差单元、社区人居环境安全评价过渡单元、社区人居环境安全评价较好单元、社区人居环境安全评价优良单元;大连市人居环境安全的空间分布中各分区所占的比例为:人居环境安全区30.598%,人居环境较安全区30.232%,人居环境安全过渡区9.678%,人居环境较不安全区12.299%,人居环境不安全区17.193%;南部滨海区人居环境安全好,北部城乡结合部人居环境安全差,呈现由南向北递减趋势;中部是国家森林公园等植被覆盖好的区域,人居环境安全好。研究表明本文所建评价模型具有普遍性,可用于不同社区人居环境因子的评价与比较。 相似文献
9.
岩溶山地聚落人口空间分布与演化模式 总被引：6，自引：1，他引：5
中国西南山区人口与聚落的演化对岩溶山区乡村规划、新农村建设、生态系统的管理和石漠化土地的治理有着重要的参考意义。利用长时间序列的高精度航片与卫片,结合实地农户调查,从20世纪60年代至2010年的聚落与人口耦合变化过程出发,在村级景观尺度开展了贵州高原中部典型峰丛洼地及其周边地区聚落空间格局变迁的定量研究,以探讨岩溶山地人口与聚落演化的模式及其机制,揭示聚落变迁过程中的人地关系动态。结果表明：① 在研究区农村37年的发展过程中,尽管农村聚落总数在不断增多,但还是形成了一些规模相对发展较快的中心村、镇;② 自然条件、交通相对较好和原来规模相对较大的聚落得到了优先发展;③ 由于农户外迁,位于中部峰丛洼地区通达性较差的部分规模较小的聚落消失或逐渐空心化;④ 在聚落和人口的自发演变过程中,一方面使部分退化的石漠化土地得到了恢复,另一方面聚落扩展严重占用了相当的优质耕地。 相似文献
10.
Beer A 《The Australian geographer》1998,29(2):223-240
"This paper examines national immigration processes and demographic change in South Australia and Tasmania over the last four decades. Particular attention is paid to the inter-censal period 1986-1991.... The paper investigates the impact of the historic make-up of immigrant flows on settlement patterns, and examines the impact on policies intended to increase immigrant settlement in these states. It argues that the policies being pursued by state and federal governments are unlikely to add to the numbers settling in these states, because they pay too little attention to migration processes, and especially the attraction of others from the source country." 相似文献
11.
草原生产力及其对气候变化的响应是全球变化研究的热点。利用ArcGIS插值技术,将蒙古高原32个气象站点数据插值成1°×1°的格点数据,然后利用CENTURY模型模拟了蒙古高原1961—2016年草原地上净初级生产力（ANPP）时空分布特征。结果表明：（1） CENTURY模型模拟的蒙古高原草原ANPP时空分布能够很好地反映该区域草原生产力的变化,草原ANPP分布由北向南,由东向西逐渐减少。（2） 草甸草原和典型草原单产均呈波动下降趋势,草甸草原下降速率较大,荒漠草原单产呈波动上升趋势,草原总产以典型草原最大,荒漠草原面积虽然最大,但总产最低。（3） 降水对草原生产力起主导作用,湿期会有荒漠草原→典型草原→草甸草原的转化,而干期的转化过程正好相反。从暖湿期→冷干期转换时,蒙古草原总产下降幅度最大,相反,则增产幅度最大。 相似文献
12.
近年来,合成孔径雷达干涉测量（InSAR）技术应用于地表沉降监测研究领域的方法与实例在国内外工程实践和科研活动中经常出现。近几十年来由于地下水的长期超量开采,华北平原已成为世界上超采地下水最严重、地下水降落漏斗面积最大、地面沉降面积最大、沉降类型最复杂的地区,地表沉降监测周期长、成本高、数据量大,通过In SAR技术的应用可有效提高地表沉降观测的精确性,为预防和减少经济损失发挥积极重要作用。 相似文献
13.
传统村落承载着中华民族的血脉和基因,乡村转型背景下,如何留住这份“乡愁”显得尤为重要。论文以湖南岳阳张谷英村和通道皇都村为例,从景观基因修补和文化基因修复的视角,探讨自组织和他组织模式下人居环境转型发展的演变路径和空间特征。研究显示：① 自组织模式下,传统村落人居环境转型机制较为灵活,实效性强,但短期稳定性差;他组织模式下的转型机制短期稳定性较强,但缺乏一定的实效性。② 自组织模式下的转型发展由内生力量自下而上推动,“双修”理念下沉发展较好,创新与适应能力强,但“双修”效果缺乏一定的规范性和整体性;他组织模式下的转型发展由外部力量自上而下推动,“双修”效果具有较强的规范性和秩序性,整体呈环状格局,但内生力量较弱,理念下沉较差,主动创新能力与适应能力低。③ 自组织模式下的转型发展具有一定的逻辑性,即文化基因修复为先,景观基因修补在后,整体呈波状起伏路径;他组织模式下的发展逻辑与自组织相反,整体呈阶梯式路径。④ 自组织模式在传统村落未来发展中能够稳固延续;他组织模式下,虽短期内可以延续,但随着内外主体的强弱转化,最终将被自组织模式取代。 相似文献
14.
针对“定居兴牧”水源工程勘测设计、建设管理中的难点问题和关键环节,分析和阐述了立项审批、建设资金、建设管理及质量安全三项保障措施,以及建立的坝工建设、工程水文计算及工程地质勘察、工程设计与施工技术体系三项技术支撑,提出了工程规模“择小放大”、泄水建筑物规模“择大放小”、抗震设计“评Ⅶ设Ⅷ”、灌溉模式“择高有压”、地质条件复杂“避让放弃”等技术措施和应把握的原则,建立了“定居兴牧”水源工程技术支撑体系;并针对牧民定居水资源保障和安置模式、水源工程水价及管理、受水区开发规模等问题进行了分析讨论,指出新疆已不具备大规模开发水土资源的条件,采取“集中定居、插花定居、分流转产”三种定居模式,是切合新疆实际的;水源及其配套工程效益的发挥,需要加快饲草饲料基地开发建设,走集约化、现代化发展之路;水价应考虑牧民承受能力和工程良性运行的需要,可采取财政扶持、分阶段逐步到位,实施定居区水务一体化管理,发挥项目的规模效应;定居区规模要做到“水土平衡、供需平衡”,防止“小马拉大车”;工程建成后,要加强水文监测,为水库安全度汛和调度提供可靠的基础依据.定居兴牧水源工程的顺利实施,赋予了“新疆效率”深刻的科学内涵,对于加速现代草原生态畜牧业发展,具有一定的借鉴、指导作用. 相似文献
15.
Kudryavstev OK 《Soviet geography》1983,24(6):430-443
The concept of a basic framework of settlement consisting of the largest cities in the USSR is developed. "The present framework shaped by cities over 100,000 and by cities over 500,000 is analyzed in terms of clusters of concentration and outlying centers. Changes in the framework over time are discussed in terms of varying sets of the 50 largest cities in various stages over the last 80 years." 相似文献
16.
Zbelo Tesfamariam Jan Nyssen Tesfaalem Ghebreyohannes Kelemework Tafere Amanuel Zenebe Jean Poesen Seppe Deckers Veerle Van Eetvelde 《Singapore journal of tropical geography》2019,40(3):476-495
Transhumance between the Afar lowlands and Tigray escarpments has been a common practice in northern Ethiopia. However, the impact of transhumance on landscape changes in the marginal grabens has not been significantly researched. Hence, this study aims to understand the process of transhumance and the linkages between social and biophysical aspects of the graben landscapes of northern Ethiopia. Google Earth (2010?2016) and Landsat Imageries (1995?2015) were used to analyse the spatio‐temporal landscape changes. Normalized Difference Vegetation Index (NDVI) was applied to measure the change in vegetation cover. Interview and Focus Group Discussions were used to collect perceptions of communities on transhumance and landscape change. The findings reveal that transhumance caused conflicts between the lowlanders and highlanders, which in turn led to displacement of communities. Consequently, the NDVI value of the abandoned settlement increased over time. Conversely, the analysis of Google Earth Imageries and NDVI values show that vegetation cover of the new settlement has decreased. Moreover, the NDVI values of the transhumance areas showed little increase due to the establishments of exclosures in the escarpments. The findings of this study can, therefore, be used to develop targeted interventions aimed at solving transhumance‐induced conflicts, displacement of communities and conservation of natural resources. 相似文献
17.
郑洛地区史前聚落遗址人居环境宜居度指数模糊综合评价 总被引：6，自引：4，他引：2
以地貌、土壤、坡向、坡度、高程5个指标构建郑洛地区史前聚落遗址人居环境指数模糊综合评价体系,使用基于地理探测器的因子探测法确定各单因素权重,根据环境驱动因子分级标准及等级值,采用梯形和三角形隶属函数计算单因素评价值,再使用加权平均的综合评价类型和等距法,得到了郑洛地区史前聚落遗址人居环境指数综合等级,运用SPSS数据探索功能,分析宜居度最高地区的具体环境特征,并分别以仰韶后期和龙山时期的实际遗址分布数据对该等级评价系统的准确性进行验证。研究结果表明,该模型评价结果较为准确可靠。 相似文献
18.
本文根据乌鲁木齐河流域7个雨量站点多年(17~61年)的月平均降水数据的统计规律,提出一种新的、能够同时满足空间维和时间维插值需求的降水分布及降水量计算模型——高斯函数参量化法。该模型根据高斯函数的几何意义和降水分布规律,给高斯函数的参数赋予了明确的物理意义,从而把对降水量和分布函数规律的计算转化为对高斯函数少量参数(1~3个)的估计。不仅能够实现山区降水在时间上和空间上的插值,而且能够实现降水量和降水分布函数的相互转换。特别是能解决在高山区降水数据稀缺条件下的降水量和降水分布估计的问题。大大提高了降水数据的可用性。 相似文献
19.
云南省掌鸠河流域近300年来聚落空间演变 总被引：5，自引：3，他引：2
研究聚落在山地中的空间演变过程对探讨历史时期山地的土地利用变化和人地关系具有重要意义。以云南省掌鸠河流域为研究区,综合利用地名志资料、历史文献资料和田野调查资料等建立聚落信息数据库,重建了流域内近300年来聚落的分布格局和演变进程。研究表明：在时间上,近300年来掌鸠河流域聚落的发展可分为缓慢增长阶段（1701-1800年）、高速增长阶段（1801-1950年）和缓慢增长阶段（1951-2000年）。在空间上,中下游河谷地带始终是聚落密度最大的区域,并呈现出由中下游向中上游,再由中上游向中下游,由河谷向两侧边远山区扩展的趋势。影响山地流域聚落演变的主要因素中,高程2200 m和2500 m、坡度20°是聚落扩展的重要界限,人口数量的增长是聚落数量增加和空间扩展的主要驱动力,少数民族的迁移与定居增强了聚落分布的垂直性特征。 相似文献
20.
中心地模式的实验研究——江苏省赣榆县和灌云县城镇网的优化设计 总被引：2，自引：0，他引：2
中心地理论提供了研究城镇体系的空间布局和等级结构的方法，对农村地区集镇体系研究更具有指导意义。本文以中心地理论为基础，对江苏省赣榆县和灌云县集镇体系的基本结构、形成机制及现伏集镇体系的不合理性进行了分析，并提出了二县集镇体系布局的优化设计。 相似文献