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1.
This study assessed spatial context and the local impacts of putative factors on the proportion of prostate cancer diagnosed at late-stages in Florida during the period 2001–2007. A logistic regression was performed aspatially and by geographically-weighted regression (GWR) at the nodes of a 5 km spacing grid overlaid over Florida and using all the cancer cases within a radius of 125 km of each node. Variables associated significantly with high percentages of late-stage prostate cancer included having comorbidities, smoking, being Black and living in census tracts with farmhouses. Having private or public insurance, being married or diagnosed in a for-profit facility, as well as living in census tracts with high household income reduced significantly this likelihood. Geographically-weighted regression allowed the identification of areas where the local odds ratio is significantly different from the ratio estimated using aspatial regression (State-level). For example, the local odds ratios for the comorbidity covariates were significantly smaller than the State-level odds ratio in Tallahassee and Pensacola, while they were significantly larger in Palm Beach. This emphasizes the need for local strategies and cancer control interventions to reduce the percentage of prostate cancer diagnosed at late-stages and ultimately eliminate health disparities. 相似文献
2.
居住选择对流动人口城市居留意愿的影响——基于一项对福建省流动人口的调查 总被引：2，自引：1，他引：2
采用2015年福建省流动人口抽样调查数据,使用序次回归模型,系统分析由住房产权类型、居住区位、居住家庭化程度和住房支付能力衡量的居住选择如何影响流动人口的城市居留意愿。结果发现：当将长期居住意愿、户籍迁移意愿和永久定居意愿3部分指标的加和定义为城市居留意愿指标时,流动人口在城市居留意愿远低于预期,真正愿意将长期居住、户籍迁移、永久定居三者统一起来的流动人口不足二成。回归模型结果表明,居住选择的确对流动人口的城市居留意愿产生显著影响,在控制流动人口的个人、家庭特征和流动状况等变量后,拥有住房所有权、居住在中心城区、与家人一起居住和更高的住房支付能力的流动人口,更愿意在城市永久定居。 相似文献
3.
基于农户调研的中国农村居民点空心化程度研究 总被引：8，自引：0，他引：8
基于中国范围的乡村人居环境调研数据,分析了中国农村宅基地空心现象。结果表明：① 中国农村宅基地空心化严重,93.5%的调研村庄有空心化现象,平均空心化率达到10.2%。② 省域农村宅基地空心化差异明显,其中华北、华东、华中地区普遍较高;③ 多种因素导致农村宅基地空心化,认为是“外出务工”、“户口迁移”、“房屋年久失修”及“一户多宅” 的受访者分别占39.94%,19.51%,25.73%和14.82%。④ 中国农村空心化宅基地再利用潜力巨大,但再利用难度大,需要从改革城乡二元体制和乡村空间重构的角度进行空心村整治。 相似文献
4.
The prevailing pattern in much of the social sciences, including geography and criminology, relies on count data. “Hotspots” — geospatial areas with disproportionally more crime than the rest of the city — are usually identified by the number of events in these areas. Yet no attention is given to their severity, or any other weighting system of harm, despite the common-sense view that not all crimes are created equal. To illustrate the value of focusing on harm in addition to count data, we turn to a spatial analysis of crime by observing crime concentrations (hotspots) against harm concentrations (harmspots), across fifteen councils in the United Kingdom. The definition of “harm” is based on the Sentencing Guidelines for England and Wales, as each crime category (n = 415) attracts a different severity weight. Both “hotspots” and “harmspots” are defined as being at least 2 standard deviations from the mean distribution within each city: This procedure creates comparable datasets. The data suggest that half of all crime events are concentrated within 3% of all street segments in the selected councils, yet harm is even more heavily concentrated, with half of all harm located in just 1% of each council [OR = 3.49; 95% CI 3.268–3.728]. The intra-unit variance was also reduced by approximately half — from 0.75% to 0.45%. We discuss the implications of using harm, in addition to counts, for research and policy by arguing that a shift in focus is required both for the development of theories and for cost-effective prevention strategies. 相似文献
5.
吉林省村域尺度下居民点空间分布特征及优化重组模式 总被引：2，自引：1，他引：1
乡村聚落的空间优化与重构是提高土地资源利用效率,改善农村生产生活条件,促进乡村可持续发展的重要手段。以吉林省为例,采用核密度估计方法和景观形状指数分析了农村居民点空间分布特征,基于农户调查数据估算了吉林省不同区域的农村宅基地闲置情况,将农村居民点长期存在的“破碎化”和日益突出的“空心化”相结合,提出了在行政村尺度下农村居民点优化重组的“整小填大”新模式。结果表明：① 吉林省农村居民点规模小且零散分布,尤其中部呈破碎化分布,形态不规则,具有较大的整治潜力;② 吉林省农村宅基地平均闲置率为18.32%,西部地区最高（24.48%）,分别高于东部和中部地区约6%和12%;③“整小填大”模式可使农村居民点数量减少44.6%,增加有效耕地面积1 046.66 km2。 相似文献
6.
Nick Revington 《The Professional geographer》2018,70(1):1-10
Challenges arising from changing demographics, expensive housing, and precarious labor have prompted recent interest in the residential geographies of young adults. Yet, despite attention to young adults' diverse housing pathways, I argue that greater focus is needed on the place-based and spatial underpinnings and effects of particular housing pathways: Connections to urban processes of “youthification”—the concentration of young adults in dense neighborhoods—and “studentification”—whereby an area becomes dominated by university students—remain underdeveloped, as do linkages between these phenomena and gentrification. I explore these connections through a critical review of extant literature to show that the enactment of some pathways is associated with particular urban processes, which might foreclose certain pathways for other individuals. Finally, I identify three crucial areas of inquiry: (1) how youthification, studentification, and gentrification interact; (2) how these processes shape and are shaped by diverging individual housing pathways; and (3) how differences among young adults such as race, ethnicity, and gender intersect with age in the course of these processes. 相似文献
7.
中国人口收缩的城乡分异特征及形成机理 总被引：2，自引：0，他引：2
在县市尺度上对2000—2010年人口收缩区的城乡分异特征进行分析,划分出城增乡减型、城乡双收缩型和城减乡增型等类型,并建立人口收缩城乡分异的理论分析框架,探讨了不同类型的形成机理,主要的发现如下：① 2000—2010年,人口收缩单元占比约为38.6%,城增乡减型单元占据绝对主体,达到34.5%,而“城乡双收缩型”和“城减乡增型”单元占比均较低。② 中部地区人口收缩区城镇人口增长普遍较快,东北地区城乡双收缩的特征较为突出,而东部和西部地区存在较明显的空间分异。③ 城镇化水平和经济发展水平对人口收缩城乡分异特征的影响最为显著,城镇化水平较高而经济发展水平较低的人口收缩区越可能出现城镇人口增长缓慢甚至城乡双收缩。④ 经济发展速度、人口自然增长水平、公共服务等因素对人口收缩城乡分异特征也存在一定的影响。 相似文献
8.
The distribution of Sarcocornia pillansii (Moss) A.J. Scott was determined by water-table depth and electrical conductivity (EC) of the groundwater. Where the groundwater was accessible (<1.5 m) and had a low EC (<80 mS cm−1), S. pillansii extended its roots down to the water-table where a suitable water potential gradient was shown to exist between the soil and roots. In areas where the groundwater was too deep and/or hypersaline, the plants grew on hummocks. The unconfined aquifer below the floodplain is linked to the estuary and although diurnal tidal waves were dampened, water-table level fluctuations were recorded between tidal events. The complex geomorphology of the floodplain influences groundwater flow, in turn affecting the distribution of the salt marsh vegetation. 相似文献
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Traditionally, the effect of wood-boring insects has been related to mechanical damage, which in severe infestations results in breakage of branches and trunks. In contrast, few studies have evaluated the physiological effects of wood-borers on the radial growth of trees. Prosopis flexuosa is the main resource for rural inhabitants in the arid Chaco of Argentina and the cerambycid Torneutes pallidipennis is the principal cause of insect damage in these forests. The presence of annual growth rings in P. flexuosa allowed us to use dendrochronological methods to assess the effect of T. pallidipennis on radial tree growth. P. flexuosa with external infestation symptoms were sampled in Chancaní (Córdoba), central Argentina. Cores from “healthy” and “infested” branches were taken and processed following standard methods in dendrochronology. Generalized Linear Models were applied to compare the growth of healthy and affected tree-ring growth series. Our results showed a growth reduction in branches with cerambycid infestation. These data strongly suggest that the biological cycles of this heartwood-borer affect the growth and normal development of trees, in addition to “mechanical” effects previously proposed. Insects may produce weakening of the host plants and a pronounced reduction in radial tree growth in the most severe cases. 相似文献
10.
以南京都市圈、苏锡常都市圈和徐州都市圈为例,从城市与区县两个尺度,研究住房价格、城市发展质量及其耦合协调度的空间格局及区域差异。结果表明:(1)3个都市圈的耦合协调度与区域差异均呈现城市尺度大于区县尺度的特征。(2)住房价格与城市发展质量空间分布格局具有相对一致性,“组团式”格局明显,南京都市圈的区域差异均最大。(3)3个都市圈耦合协调度水平整体不高,处于中级及以下协调水平,且分布呈空间依赖性;住房价格与城市系统及其经济、社会、文化、生态4个子系统发展质量的耦合协调度由大到小依次为苏锡常都市圈、南京都市圈、徐州都市圈,且耦合协调度区域差异既表现出共振性又表现出尺度敏感性。(4)根据协调状态及主导低耦合失调的原因,将城市划分为6种类型,区县划分为8种类型。 相似文献
11.
Most scholarship on rural–urban migration in Sub-Saharan Africa demonstrates that migrants tend to move in a “circular” fashion and only spend short periods of time in cities before returning home to rural villages. However, some scholars working on the impacts of climate change on migration suggest that deteriorating environmental conditions may undermine rural livelihoods and lead people to move to cities for longer periods of time. If this is true, then climate change threatens to accelerate urbanisation and lead to renewed stress on urban infrastructure. The purpose of this paper is to explore these positions and we do so by collecting survey [n = 241], in-depth interview [n = 75] and focus group [n = 123 participants] data from rural and urban Malawi. Two key results stand out as significant. The first is that migrants in Malawi's capital city tend to stay in the urban environment for longer periods of time than conventional understandings of migration would predict. The second key result is that climate change may actually lead, in the case of Malawi, to reverse (i.e urban–rural) migration. This is because many of the people in Malawi's cities depend on products produced in rural environments (e.g. food and fuelwood). If climate change undermines rural livelihoods, then many urban residents will find the basis of their livelihoods removed and will likely respond by moving back to rural villages. Overall, our results, therefore, suggest that in at least one case the effect of climate change on migration may not be to increase migration towards cities but to stimulate an exodus from cities and back to the rural countryside. 相似文献
12.
The semiarid southwestern United States is an area of rapid population growth. Urban development is encroaching upon many ecosystems, including riparian areas. Because most stream miles in the southwestern United States occur along ephemeral streams, recognizing how these ecosystems are affected by increasing urban land covers is imperative. In this study, we recorded air temperature at 30 cm above the ground surface within riparian ecosystems along nine ephemeral stream reaches in three levels of housing density: High Density (HD: >13 houses/hectare); Moderate Density (MD: 4–8 houses/hectare); Low Density (LD: <1 house/hectare) for two years in a rapidly growing city in southern Arizona. Annual and seasonal average diurnal 30-min air temperatures for each treatment show that HD air temperatures were consistently higher than LD and MD temperatures (∼0.5–1.5 °C) during the late-evening/early-morning and midday hours. Winter temperatures had the largest differences between HD and LD sites, as much as 1.4 °C. Because physiological activity in these riparian ecosystems is largely temperature-dependent, temperature shifts associated with increased housing density could result in major ecosystem changes in these semiarid areas. 相似文献
13.
This study aims to investigate the spatial and temporal dynamics of housing prices associated with the 2007 U.S. housing-market bubble in Midwest Pinellas County, Florida. Two methods were used to examine the spatial and temporal dynamic of price levels: housing characteristic influence estimation and a hedonic modeling approach. Two consistent spatial patterns emerged in the estimated coefficients associated with various housing characteristics, with definitive changes occurring at 600 m and 2200 m from the coast. These changes suggested the existence of three geographical submarkets: a coastal, an intermediate or transitional, and an inland submarket. Three temporal stages were observed from the coefficient trends associated with various housing characteristics: 2002–2005 (bubble-growing), 2006–2008 (bubble-burst), and 2009–2011 (post-bubble). The hedonic models demonstrated a complexity in the determinant of housing prices during the housing peak-bubble period. The inclusion of submarket dummy variables in the hedonic models improved the amount of explained variation. The R2 values of the hedonic models from 2002 through 2008, followed by a decrease after the bubble-burst period. The pre-bubble-burst trend in R2 suggests that predictable market forces were at work; partly driven by irrational expectations of housing buyers and the perceptions of run-away housing prices during the growth phase of the bubble. 相似文献
14.
Alternative and Virtual Rurality: Agriculture and The Countryside as Embodied in American Imagination 总被引：1，自引：0，他引：1 
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下载免费PDF全文 Lisa M. Butler Harrington 《Geographical review》2018,108(2):250-273
Affection for agrarian livelihoods and rural and small‐town environments has long been held by residents in many of the world's “more developed” countries. Although the rural proportion of the U.S. population has shrunk to a minority over the last century, fondness for rurality continues to manifest itself in a number of ways. Attachment to the rural ideal or rural idyll can be considered as attachment to the idea of a type of place, rather than specific place attachment. Based on literature, field observation, computer searches, and data from the U.S. Census of Agriculture, connections to idea(l)s of rurality apparent in popular culture are identified and illustrated. These include rural and agricultural tourism, small‐scale farming and large‐lot rural subdivisions, urban agriculture, farmers’ markets and community‐supported agriculture, creation of housing developments around farm activities, and rural‐named housing and business developments. Idealized relationships with rurality call upon health and well‐being, connecting to nature, aesthetics, privacy, and respect and nostalgia for rural livelihoods. 相似文献
15.
除了工业发展的动力之外,旅游作为一种市场动力,已被证明可以有效引导乡村城市化的实现。因此,在旅游发展的引导下,乡村城市化背后的驱动力以及各动力主体之间的作用关系亟待新的探索和突破。文章引入“国家―市场―社会”作为分析城市化驱动力的三元框架,以云台山景区内的乡村为例,通过观察、访谈等定性研究方法,认为在旅游发展所引导乡村城市化的背后,国家、市场、社会这三元动力在动力主体、作用发挥、角色扮演上和原本框架中各个动力的所指相比都已经发生了转变,主要体现在市场动力从市场供给一方转变为市场需求一方,社会动力从村民组织转变为村民个体。通过案例的实证分析,总结出了地方政府、需求市场、村民个体作为旅游发展引导下乡村城市化的三元驱动力,“地方政府―需求市场―村民个体”的分析框架也是对“国家―市场―社会”分析框架针对具体研究问题的有效修正和补充。 相似文献
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17.
电子商务在农村推进中，出现了淘宝卖家集聚于某些村落的现象，这些村落被称为淘宝村。近几年淘宝村在农村地区快速发展，有些淘宝村甚至成为带动县域经济发展的新引擎。以河北省羊绒产业集聚区为案例，运用ArcGIS空间分析方法，探讨了县域尺度下基于当地产业发展起来的淘宝村的时空发展特征，并尝试分析其影响因素及影响机理。研究发现：（1）河北清河、南宫等地以羊绒产业为主导，其发展主要经历了两个时期：羊绒产业快速集聚时期和羊绒产业转型升级电子商务时期；（2）淘宝村的时空发展过程大致可以分为三个阶段：初步发展—迅速发展—平稳发展，以东高庄村为中心，淘宝村通过渐进式、跳跃式向外围呈环状展开分布，最终形成“小范围集聚，大范围分散”的空间格局，并呈现近地缘扩散及沿交通轴线发展的空间特征；电子商务扩散强度随距离增长逐渐衰减，目前淘宝村的辐射范围仅涉及清河县东北部及南宫市的东南部地区，而两县的其他地区尚未出现淘宝村；（3）能人效应、农区特有的社会网络关系、雄厚的产业基础、交通条件以及政府的扶持等多重因素共同促进了县域电子商务蓬勃发展。 相似文献
18.
Generic 3D interpolation of Holocene base‐level rise and provision of accommodation space,developed for the Netherlands coastal plain and infilled palaeovalleys 下载免费PDF全文
下载免费PDF全文 We present an interpolation model that describes Holocene groundwater level rise and the creation of accommodation space in 3D in the Rhine‐Meuse delta – the Netherlands. The model area (ca. 12 400 km2) covers two palaeovalleys of Late Pleistocene age (each 30 km wide) and the overlying Holocene deposits of the Rhine‐Meuse delta, the Holland coastal plain, and the Zuiderzee former lagoon. Water table rise is modelled from 10 800 to 1000 cal. BP, making use of age‐depth relations based on 384 basal peat index points, and producing output in the form of stacked palaeo groundwater surfaces, groundwater age‐depth curves, and voxel sets. These products allow to resolve (i) regional change and variations of inland water table slopes, (ii) spatial differences in the timing and pacing of transgression, and (iii) analysis of interplay of coastal, fluvial and subsidence controls on the provision of accommodation space. The interpolation model is a multi‐parameter trend function, to which a 3D‐kriging procedure of the residuals is added. This split design deploys a generic approach for modelling provision of accommodation space in deltas and coastal lowlands, aiming to work both in areas of intermediate data availability and in the most data‐rich environments. Major provision of accommodation space occurred from 8500 cal BP onwards, but a different evolution occurred in each of the two palaeovalleys. In the northern valley, creation of accommodation space began to stall at 7500 cal BP, while in the southern valley provision of new accommodation space in considerable quantities continued longer. The latter is due to the floodplain gradient that was maintained by the Rhine, which distinguishes the fluvial deltaic environment from the rest of the back‐barrier coastal plain. The interpolation results allow advanced mapping and investigation of apparent spatial differences in Holocene aggradation in larger coastal sedimentary systems. Furthermore, they provide a means to generate first‐order age information with centennial precision for 3D geological subsurface models of Holocene deltas and valley fills. As such, the interpolation is of use in studies into past and present land subsidence and into low land sedimentation. 相似文献
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Medium term (decadal) beach profile response to external forcing was assessed on two adjacent embayed beaches (North and South Sands) in Pembrokeshire, West Wales. Both have contrasting physical and geological characteristics: a headland bay backed by dunes and a constrained embayment backed by geological promontories, promenades, walls and rock revetments. Paired t-tests showed significant changes at all cross-shore profile locations (95% confidence), with south and north shores respectively exhibiting falling and rising beach levels. South to north sediment transport was revealed by volumetric variation (r = 0.83), and longshore sediment distribution (r = 0.91). North Beach level variations lagged behind South Beach by one-year (r = 0.85). A reduction in high wind speed frequency, coincidental to spring tides, was correlated with falling South Beach levels (r = 0.87) and rising North Beach levels (r = −0.92). Heavily refracted Atlantic swells also have contrasting effects on these systems. Multiple regression models applied to beach level change for both systems showed high correlation (R2 = 0.93 and 0.85 respectively), suggesting that swell wave period and strong north-westerly winds that occur during high spring tides had cumulative effects. Furthermore, variations in the North Atlantic Oscillation (NAO) index were correlated to cumulative changes in mean sea level, wind wave height and south-westerly winds (R2 = 0.75). While NAO variations were linked to variations in South Beach morphology, it was insignificant on North Beach (r = −0.72 and −0.14 respectively). Cross-correlation analyses showed that North Beach morphological changes lagged behind NAO Index variation by one-year with much improved correlation (r = 0.77). A similar scenario existed when comparing Mean Sea level and beach level differences (r = −0.54 and −0.32 respectively). Similar behaviour should be exhibited at other worldwide embayments, and it is suggested that this work is repeated to establish specific responses, to will underpin intervention or no active intervention strategies. 相似文献
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采用网络资料收集、深度访谈和问卷调查等方法，对潮汕宗祠的地方意义、情感互动和内生效用展开分析，探讨了潮汕宗祠对地方感的塑造作用及其与乡村治理的内在关联。研究发现，潮汕宗祠作为同姓宗亲地域联系和情感连结的物质空间载体，通过其蕴含的地方文化、宣传展演和节庆活动等构建乡村地域的情感依恋与价值认同，进而形成地方依恋和地方认同。此外，潮汕宗祠通过建筑的形式扎根于地方，并作为乡村地域的异质性空间重构着乡村的地方性，并赋予乡村空间更多的文化内涵，以塑造乡村主体的共同价值和情感认同。诚然，潮汕宗祠的地方意义是通过多主体的共同缔造来实现的，以历史文化、个体记忆和物质资本等塑造自身的地方、民族的地方和跨界的地方。研究基于地方感和乡村治理的视角，强调物质文化载体的社会建构作用，探索乡村文化空间与乡村治理的互动，在实证层面回应了文化治理的积极意义。就现实意义而言，文章通过对潮汕宗祠地方性和根植性的讨论，旨在为乡村文化空间的营造、文化自信的建立和乡村治理提供一定的参考价值。 相似文献