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排序方式: 共有172条查询结果,搜索用时 15 毫秒
71.
As a result of the opening of the borders of the former Soviet Union, Israel has been the destination of numerous immigrants. This article deals with the impact of immigration between 1989 and 1994, upon three towns in the south of Israel, Be'er Sheva, Ashkelon and Kiriat Gat. These towns correspond to three socio-economic levels of urban area in the southern region. On the one hand, the immigrants from the former Soviet Union arrive with specific demands, on the other hand the political, economical and social context in Israel is very unusual. The sucessful integration of immigrants and the constructive development of the host country depend on the conformity of these demands and proposals. What the government offers in terms of housing, reception and employment in each of the three towns plays a key role: the town's social and economical heritage influences the integration of the new population while at the same time the arrival of a new workforce influences the development of the local area. Every town wants to grow and reinforce its position in the region, but only the large town, Be'er Sheva, is able to offer a certain diversity and therefore answers more fully the needs and wants of this new population. Government decisions and policies are not made to oppose the liberal economic system and to suppress the spacial inequalities despite some measures aiming at a more equal balance. The importance of heritage and the lack of communal development schemes within regions together ensure the continuation of qualitative inegalities in the south of Israel and even accentuate the problem. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
72.
天津市潮滩活体和埋藏有孔虫群的分布及地质环境意义   总被引:1,自引:0,他引:1  
对天津市潮滩8条垂直于海岸线剖面的57个表层沉积物样品进行了活体和死体有孔虫分析鉴定、粒度分析、含盐量测定,利用全站仪对剖面进行了水准测量,同时测定了海水盐度。研究了天津市潮滩有孔虫群的组成、数量及分异度等特征;通过聚类分析将天津市潮滩活体有孔虫群分为7个带,埋藏有孔虫群(活体+死体)分为5个带,但除了埋藏群Ⅰ、Ⅳ与活体有孔虫群Ⅰ、Ⅳ组合特征一致外,其他各带的组合特征及分带界线均不一致。通过分析活体有孔虫群分带与沉积物含盐量、海水盐度、潮位、沉积物组成等生态环境参数的关系,探讨了活体有孔虫群的主要控制因素;通过分析埋藏有孔虫群分带与潮位、沉积物粒径、现代沉积速率等沉积环境参数的关系,探讨了埋藏有孔虫群的搬运及沉积作用。指出了天津市海岸带活体有孔虫群和埋藏有孔虫群的关系、环境特征及地质意义,为该区高精度的古沉积环境划分提供了重要指标。  相似文献   
73.
Autumn living coccolithophores in the Yellow Sea and the East China Sea   总被引:1,自引:0,他引:1  
An investigation was carried out on living coccolithophores(LCs) distribution in the Yellow Sea and the East China Sea from October 17 to November 24, 2011. A total of 223 samples from different depths were collected at 48 stations. Totally 18 taxa belonging to coccolithophyceae were identified using a polarized microscope at the 1 000× magnification. The maximum species abundance was found at the outside of Transect P. The dominated species were Gephyrocapsa oceanica, Emiliania huxleyi, Helicosphaera carteri, and Algirosphaera robusta. The abundance of coccoliths and cells ranged 0–2 965.73 coccoliths/mL, and 0–119.16 cells/mL, with the average values of 471.00 coccoliths/mL and 23.42 cells/mL, respectively. The LCs in surface layer were mainly observed on the coastal belt and middle part of the survey area. The comparison among Transects A, F, P and E indicated lower species diversity and less abundance in the Yellow Sea than those of the East China Sea. The highest abundance of LCs was found in transect F and P. The coccolith abundance increased slightly from surface to bottom in the water column, but the highest value of the cell abundance was observed in the depth of 10–30 m. Temperature, depth and nutrient concentration were suggested as the major environmental factors controlling the distribution and species composition of LCs in the studying area based on canonical correspondence analysis(CCA).  相似文献   
74.
Small-scale fisheries are crucial for improving livelihoods by providing fisher employment, and food security. As part of their work, fishers frequently move to different fishing communities to catch and trade in fish. This paper analyses the living circumstances of artisanal fishers and discusses their mobility patterns, lodging arrangements, and the difficulties they encounter as they carry out their work. This paper is based on a study that involved 385 artisanal fishers in the fishing community of Elmina in the Komenda Edina Equafo Abirem (KEEA) Municipality in the Central Region of Ghana. The results show that there are not many suitable places to stay for fishers when they travel from home to other fishing locations, and the few places that do offer affordable lodging also lack toilets, bathrooms and drinkable water. The paper also reflects on the gendered dynamics of these and related issues of insecurity for women in this case study. District authorities whose economies are heavily dependent on fishing ought to collaborate with private housing developers and the state to build affordable lodging facilities with standard household amenities like water, toilets and baths in fishing destinations to address the housing issues faced by fishers while travelling.  相似文献   
75.
Pejrup, Morten: Bottom sediments in Ho Bugt—a wadden sea environment. Geografisk Tidsskrift 81: 11–16, Copenhagen, June 1981.

Twenty eight samples of bottom sediment from Ho Bugt, located at the west coast of Jutland, have been anlysed, and the variations within the fine and the coarse fractions described in detail. A method for classifying estuarine- and wadden-sea sediments is presented. The classification together with special characteristics found for the coarse fraction is used as a basis for a sediment chart for the northern part of Ho Bugt.  相似文献   
76.
通过分析大连市商品住宅售价的分布情况,发现大连市居住空间分异现象已初见端倪,城市社会极化、空间隔离明显,居住空间混合居住依然存在,但尚未出现明显集聚的“富人区”和“穷人区”,居住空间分异较合理.就此对其特征及产生原因进行了综合研究,探讨居住空间分异的形成机制,认为多层次居住区分化、住宅商品化和自主性择居是大连市居住空间分异形成原因,针对大连市居住空间分异的现状特征的形成机制,采取以下调控策略:加强城郊结合部的公共基础设施建设;注重居住区的文化建设,创造多样化交往空间;采用混合居住的布局模式.  相似文献   
77.
城市老年人居家养老满意度的影响因子与社区差异   总被引:5,自引:2,他引:3  
颜秉秋  高晓路 《地理研究》2013,32(7):1269-1279
针对社区居家养老服务供给滞后、设施及服务功能单一、布局不合理等问题,基于北京市区内6 类典型社区的问卷调查数据,运用结构方程模型,构建了包含老年人居住环境因子在内的城市老年人居家养老满意度模型;并引入社会学及心理学常用的结构方程模型多群组分析(SEM Multiple-Group Analysis) 方法,以分析不同社区内各个老年特征群体的不同养老需求。分析结果表明:① 老年人的社会支持度(指来自家庭、朋友、邻里和社会的各种支援) 构成居家养老满意度的首要影响因子;② 社区养老服务发展程度对居家养老满意度的影响广泛而显著;③ 按照不同社区的居家养老模型及其影响路径特征,可将城市居住社区划分为居住环境影响型社区、基本因子影响型社区、社会环境影响型社区、社会环境+居住环境影响型社区等4 种类型,不同类型社区的老年人在居家养老需求方面具有显著差异。以上结果揭示了提升对老人的社会支持度的重要意义以及因地制宜完善社区居家养老服务的迫切性。  相似文献   
78.
基于GIS的新疆和田地区人居环境适宜性评价   总被引:1,自引:0,他引:1  
人居环境是人类生存和发展的基础。运用GIS和RS技术采用单因子评价和综合评价模型,系统地归纳了国内外人居环境评价研究的理论基础和应用研究成果,利用DEM与[WTBX]NDVI[WTBZ]数据将多年平均气温、降水量、人口和GDP等要素的栅格数统一到1 km×1 km的栅格尺度,以此反映干旱区适宜性的空间分布特征。通过数字评价模型分析,结果表明:和田地区的人居环境指数介于1.139~4.495之间;整体分布景观是从和田河流域、克里雅河流域等绿洲区向北部沙漠区和南部山脉区递减,大部分地区受到自然条件的限制,人居环境中高级适宜区面积最少,占全研究区面积的1.04%,较适宜区占5.95%,中等适宜区占21.13%、难适宜区和不适宜区占71.68%,表明自然环境基础很恶劣,生态环境相当脆弱。因此,开展和田地区人居环境适宜性评价研究,对干旱区生态环境保护具有现实意义。  相似文献   
79.
Harmful algal blooms of the dinoflagellate Cochlodinium polykrikoides are of worldwide environmental concern. Previous field studies have demonstrated the association of such algal blooms with free‐living bacteria (FLB) and particle‐associated bacteria (PAB). In the present study, we report evidence for bacterial association with C. polykrikoides in laboratory culture. Sampling was performed at different growth stages (lag, exponential and stationary) and pyrosequencing was used to identify taxa. As a result, the community structures of FLB and PAB were elucidated and significant differences between FLB and PAB were identified by hierarchical cluster analysis and the similarity profiles test (= .05). The relative abundances of bacterial operational taxonomic units distinctly changed in response to the different phases of C. polykrikoides growth. The Roseobacter genus Marivita and the Flavobacterium genus Winogradskyella were dominant in the FLB and PAB associated with C. polykrikoides, respectively. The Roseobacter clade, which has also exhibited associations with C. polykrikoides blooms in field samples, may influence host cell growth through the provision of vitamins.  相似文献   
80.
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