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121.
BOOK REVIEWS     
Book Reviewed in this article: Unfairly Structured Cities . Blair Badcock Religion and Rural Revolt . Janos M. Bak and Gerhard Benecke The Industrial Geography of Canada . Anthony Blackbourn and Robert G. Putnam The Cuban-American Experience, Culture, Images, and Perspectives. Thomas D. Boswell and James R. Curtis Quaternary Paleoclimatology . R. S. Bradley Development and Crisis in Brazil, 1930–1983 . Luiz Bresser Pereiras Centres of Origin in Biogeography . John C. Briggs Analytical Urban Geography . Martin Cadwallader Geomorphology . Richard J. Chorley , Stanley A. Schumm, and David E. Sugden South Africa: The Impact of Past Geographies . A. J. Christopher The Geography of Underdevelopment. A Critical Survey . D. K. Forbes Health Care in Developing Countries . Wilbert M. Gesler Place to Grow Old: The Meaning of Environment in Old Age . Stephen M. Golant The Emerging Marine Economy of the Pacific . Chennat Gopalakrishnan An Introduction to Agricultural Geography . David B. Grigg The Soviet Union: A Geographical Study . G. Melvyn Howe Geographical Aspects of Health: Essays in Honour of Andrew Learmonth . N. D. Mc Glashan and J. R. Blunden Physical Geography: A Landscape Appreciation . Tom L. Mc Knight Mountain Experience. The Psychology and Sociology of Adventure. Richard G. Mitchell Jr . Systematic and Regional Biogeography. Stanley A. Morain The Economic Transformation of American Cities. T. J. Noyelle and T. M. Stanback , Jr . Normal Accidents: Living With High-Risk Technologies. Charles Perrow Vanishing Farmland: A Legal Solution for the States. Sarah E. Redfield Applied Methods of Regional Analysis: The Spatial Dimensions of Development Policy. Dennis A. Rondinelli Urbanization in Romania. A Geography of Social and Economic Change Since Independence. Per Ronnas Statistical Techniques in Geographical Analysis. Gareth Shaw and Dennis Wheeler The Granite Garden: Urban Nature and Human Design. Anne Whiston Spirn Political Geography: Recent Advances and Future Directions. Peter Taylor and John House Geographia y Medio Ambiente. Manuel Valenzuela -Rubío Nãgara and Commandery: Origins of the Southeast Asian Urban Traditions. Paul Wheatley The Common Fisheries Policy of the European Community. Mark Wise Geography and Gender. Women and Geography Study Group of the IBG Technological Hazards. D. J. Zeigler , J. H. Johnson , S. D. Brunn  相似文献   
122.
Warm-sector heavy rainfalls along the south China coast from April to June during 2009–2014 can be divided into two main types based on their low-level circulations. Type I is the southerly pattern with meridional convergence line at the west of the Pearl River estuary, which is formed by the convergence of southeasterly, southerly, and southwesterly flows. Type II is the southwesterly pattern with a latitudinal convergence line at the east of the Pearl River estuary, which is formed by the convergence of westerly and southwesterly flows. Statistics on 6-hourly heavy rainfall events indicates that, during the afore-mentioned 6 years, there were on average 73.2 occurrences of the southerly pattern and 50.3 occurrences of the southwesterly pattern per year. After the onset of summer monsoon in the South China Sea, the occurrence frequencies of both patterns increase remarkably. The synthetic diagnosis of pattern circulation shows that, at 500 hPa, for the southerly pattern, there is a broad warm high ridge, and a temperature ridge is behind the high ridge, which causes an obvious warm advection at the high ridge area. There is no frontal region. For the southwesterly pattern, the circulation is a weak trough with a temperature trough behind it. The position of the frontal region is near Yangzi River, and the south China coast is in the warm-sector of the frontal region. At the vertical cross-section of each of the two categories of heavy rainfall, there is a strong vertical motion center stretching to 400 hPa, where the convergence layer in the rainfall region is deep and with several vertical convergence centers overlapping one another. Both types of heavy rainfalls are with abundant water vapor, accompanied with deep convective instability energy layers, and with strong release of latent heat caused by condensation of water vapor. The release of latent heat leads to the warming-up and stretching of the air column, thus strengthens deep convergence and vertical velocity upward. There is a stronger latent heat-release in the southwesterly pattern than in the southerly pattern, while in the southerly pattern, the warm advection at middle and upper levels is stronger than the latent head release. To study the thermo-dynamic development mechanisms, weather research and forecasting model (WRF) numerical simulations are made and the results show that, in the two rainstorm regions, latent heat release warms up the air column, hence significantly increase the depth and strength of the vertical velocity. Moreover, the release of latent heat strengthens convergent circulation at lower levels and weakens divergent circulation at middle levels, whose influence can be as strong as 30%–50% of the wind circulation strength of the two types of the warm-sector heavy rainfall over the south China coast, and further enhances deep convection, promoting warm-sector storm development.  相似文献   
123.
对2008—2014年中国东部海域春季海上发展气旋进行了统计与诊断分析。结果表明:1)这类气旋属于较浅薄的低值系统,垂直伸展高度多在600 h Pa以下,水平尺度多在1 500 km以内。伴随的强天气为大风、大浪与强降水,落区主要位于气旋东南部。2)气旋环流各层的大风急流区构成了气旋的东南部位,称为气旋急流。从高层到低层,气旋急流轴在垂直方向上呈逆时针旋转,形成气旋上大下小的漏斗形状。3)气旋急流左侧的气旋式切变有利于气旋中心强度的维持,上层气旋急流左侧对应下层气旋急流前部流速辐合区,有利于气旋式动力抽吸及在气旋东南部形成强的垂直上升运动区。各层气旋急流配置导致气旋的非对称结构,以及气旋要素的非对称分布。气旋急流向气旋中输入螺旋度以及充足的水汽,并在东南部强烈抬升,增强了凝结潜热释放,从热力和动力两方面促进气旋发展及强天气落区。4)春季下垫面温度分布(锋区)有利于气旋急流的增强,并通过西北部非绝热冷却和东南部非绝热加热,增强气旋斜压性。高空环境西风急流位于气旋右侧,形成了整层偏差风辐合,有效增强低层气旋急流。同时高空动量下传位于气旋西侧,首先增强气旋西北部的弱流部分(即气旋螺旋结构的下沉支),进而增强整个气旋的螺旋环流,促使气旋急流也从下层开始增强。  相似文献   
124.
基于联合国多维贫困指数、世界经济论坛旅游竞争力报告及国际货币基金组织提供的贫困国家经济数据,构建了旅游竞争力与经济发展评价指标体系,通过信息熵值法确定指标权重,再运用耦合协调度模型测度2008-2017年间贫困国家旅游竞争力与经济发展之间的耦合协调度,研究其时空演变规律及成因机制。研究发现:①贫困国家旅游竞争力与经济发展的的耦合协调现状不容乐观,基本都处于失调或接近失调状态,但从时间发展来看,有向协调方向缓慢发展的趋势,且耦合协调度的区域差异正在缓慢缩小;②从耦合协调类型上看,大部分贫困国家为经济滞后型,其余为旅游—经济同步型,尚无旅游滞后型;③贫困国家旅游竞争力与经济发展的耦合协调度等级分布呈现较明显的空间集聚特征,非洲地区耦合协调度等级相对最低,南美洲及加勒比地区耦合协调状态相对较好,东南亚地区则呈现局部异质性。  相似文献   
125.
Olivier Coutard 《Geoforum》2008,(6):1815-1820
This paper introduces a collection of case studies aimed at “Placing Splintering Urbanism”, in reference to the thesis developed by Graham and Marvin [Graham, S., Marvin, S., 2001. Splintering Urbanism. Networked Infractructures, Technoloical Moblilities and the Urban condition. Routledge, London]. Whilst acknowledging the value of the thesis as an analytical framework in opening the way to innovative understandings of contemporary urban dynamics, the paper argues that, taken together, the articles in this themed issue seriously challenge the “splintering urbanism” thesis theoretically, empirically and methodologically. They question in particular the postulated universality of the “modern infrastructural ideal” and of “unbundling” and “bypass” processes — all of which are key elements in Graham and Marvin’s argument — as well as the assertion that reforms in infrastructure sectors should generally result in more discriminatory, socially regressive patterns of provision of essential services and more splintered urban spaces. Based on these fundamental critiques, the paper concludes that one cannot speak of “splintering urbanism in general” — i.e., as a global trend — in any meaningful analytical way.  相似文献   
126.
工业用水零增长的条件分析——发达国家的经验   总被引:25,自引:2,他引:25  
本文探讨发达国家工业用水零增长出现的时间及其原因。发达国家的经验表明 :较高的环境保护要求是工业用水减少的宏观社会背景,产业结构升级则是工业用水实现零增长的直接原因。第二产业所占的 GDP比重和就业比重的开始降低是工业用水减少的前奏,第二产业比重的明显降低——其实质是高耗水的重化工行业规模的绝对萎缩——几乎是工业用水停止增长的充分条件。  相似文献   
127.
发达国家森林资源分布特点和开发利用现状   总被引:1,自引:0,他引:1  
本文分析了发达国家森林资源的分布特点、开发利用现状和影响林业发展的问题,并试用区域非均衡理论对发达国家的森林资源的合理开发利用及发展战略提出一些见解。  相似文献   
128.
90年代全球环保浪潮对世界贸易的影响   总被引:1,自引:0,他引:1  
本文阐述了90年代全球环保浪潮对世界贸易的影响,重点分析了新的环境和贸易政策对世界贸易的制约,绿色产业的发展及在优化世界贸易商品结构中的作用,“绿色壁垒”下发展中国家面临的新挑战。  相似文献   
129.
Summary In Kenya 1974/5 and in Malawi 1984/5 trial sections of bituminous-surfaced low volume roads were constructed using as-dug laterite in place of stone or stabilized material as a base course.The laterite did not conform with any accepted specifications but performed equally well when compared with adjoining sections of road using stone or stabilized material as a base.The construction procedures employed are described. A period of 4–6 weeks between the compaction of the base and its surfacing is considered essential if the road is to perform satisfactorily. During this period it is exposed to the weather and traffic or to periodic watering and rolling. This treatment fills any cracks with dust or mud and closes them by the kneading action of rubber-tyred traffic. The bituminous surfacing is applied where the base has dried out to about half the optimum moisture content and is extended about 1.5 m beyond each edge of the carriageway.In 1984, $40000 US per km was saved in Malawi in this way, approximately 70% being in convertible currency without incurring additional maintenance or vehicle operating costs.  相似文献   
130.
中国农民工聚居区研究进展   总被引:1,自引:0,他引:1  
作为快速城市化、工业化、相关制度和文化背景等多种因素影响下形成的一种聚落形态,中国农民工聚居区诞生于20世纪80年代。本文在梳理相关研究的基础上,将农民工聚居区研究划分为起步阶段、扩展阶段、社会空间转向和社区治理3个阶段。总体上看,对农民工聚居区的研究,在空间形态方面从静态走向动态,社会网络方面从群体走向空间,形成机制方面从传统的社会学、城市地理学视角转向制度经济学、文化地理学和空间生产视角,聚居区从改造管理走向合作治理,研究方法日益多元化。论文从研究思潮、研究视角、研究重点等方面比较了中国农民工聚居区与西方移民聚居区的差别,并对未来研究作了展望。  相似文献   
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