Beyond world cities: Central America in a global space of flows   总被引：1，自引：0，他引：1  

Ed Brown  Peter J. Taylor  & Gilda Catalano 《Area》2002,34(2):139-148

Central America is a region without a world city. Traditionally, the region's national projects have been based upon openness to the world economy: how do the region's contemporary transnational projects connect to the world economy under the new conditions of openness that is contemporary globalization? Focusing upon advanced producer services, three connections into the world city network are identified: global service firms operating directly in Central American cities, local service firms operating indirectly through extra-regional world cities and global service firms operating through Latin American regional offices. Miami is confirmed as the primary world city through which Central America connects into the world economy  相似文献   

The RGS, exploration and Empire and the contested nature of surveying     

Peter Collier  & Rob Inkpen 《Area》2002,34(3):273-283

In 1879, the RGS started courses in practical surveying based on the methods used by navigators. Subsequently, RGS courses, increasingly under the influence of former members of the Survey of India, changed in character. At the same time as the nature of appropriate surveying was being negotiated within the RGS, the debate over the academic nature of geography also took shape. The development of the 'new' geography reflected the conflicts within the RGS Council over the meaning of scientific geography.  相似文献   

The application of GPR to barrier-lagoon sedimentation study in Boao of Hainan Island     

YIN Yong  ZHU Dakui  TANG Wenwu  Martini I. Peter 《地理学报》2002,12(3):313-320

Sedimentary successions and internal structure of the coastal barrier-lagoon system of Boao, eastern Hainan Island were studied through utilizing data from test holes and trenches and ground-penetrating-radar (GPR) profiles. During late Pleistocene, fluvial and delta plains developed over an unevenly eroded bedrock during low sea level stand, followed by the formation of littoral and lagoon facies and defined coastal barrier-lagoon-estuary system during the post-glacial uppermost Pleistocene-lower Holocene eustatic rise of the sea level, and the upper Holocene high stand. GPR results show that Yudaitan, a sandy coastal bar backed by a low-laying land (shoal) just east of the active lagoon, is a continuous, parallel and slightly-wavy reflectors indicating homogeneous sandy or sandy gravel sediments, and inclined reflectors partly caused by progradation and accumulation of beach sand and gravel. Quasi-continuous, hummocky and chaotic reflectors from the shoal of Nangang village correspond to mixed accumulation of sands and clay. This research indicates the GPR is a non-intrusive, rapid, and economical method for high-resolution profiling of subsurface sediments in sandy gravelly coast.  相似文献   

Changing Rural Spaces: Deregulation and the decline of tobacco farming in the Mareeba-Dimbulah Irrigation Area,Far North Queensland     

Peter Griggs 《The Australian geographer》2002,33(1):43-61

The growing of tobacco was one of the most tightly regulated industries in Australia, until deregulation in 1995. Commonwealth regulations controlled the area cultivated with tobacco, the number of growers (i.e. quota holders) and marketing arrangements for tobacco leaf. This paper begins by outlining the nature and historical development of controls in the tobacco-growing industry, and discusses how the Commonwealth government removed the industry's regulatory and protective framework in 1995. The third part of the paper examines how deregulation has impacted upon the Mareeba-Dimbulah Irrigation Area, Far North Queensland, where small farmers produced 60 per cent of Australia's tobacco in 1995. The discussion will show that the agricultural landscape once dominated by tobacco has been transformed, as local farmers abandoned growing tobacco in favour of sugar cane, avocadoes, mangoes, macadamia nuts and other small vegetable crops (e.g. navy beans, pumpkins). Tobacco, once promoted by the Queensland government as a crop to facilitate closer settlement in the Mareeba-Dimbulah Irrigation Area, will have almost vanished from the landscape by 2002.  相似文献   

Employment and Socio-spatial Relations in Australia's Cultural Economy   总被引：1，自引：0，他引：1  

Chris Gibson  Peter Murphy  Robert Freestone 《The Australian geographer》2002,33(2):173-189

This paper examines the significance and contribution of Australian 'creative' industry activities in light of recent debates on the emergence of the 'cultural economy of cities'. First, census employment data and business location counts are used to illustrate patterns of metropolitan primacy and concentration in the cultural industries both across states and in Sydney. Second, the specificities of the locations of cultural production, and the links between cultural industry activities and wider urban-regional change are explored in more detail. A set of observations of urban-regional change is used to demonstrate how the notion of 'cultural economy' should include complex interactions between the material activities of consumers and producers, and the discursive worlds of image makers and place marketers. Urban renewal, housing market pressures and intra-regional migration all mediate Australian experiences of the 'cultural economy'. Such interactions, in addition to key quantitative data on employment and business activity, suggest important policy considerations.  相似文献   

南极考察站废弃物对贼鸥食性的影响          下载免费PDF全文

王自磐 《极地研究》2003,15(3):177-185

对南极乔治王岛菲尔德斯半岛贼鸥的食性生态进行观测与研究 ,结果表明 ,本区贼鸥的食物结构中 ,自然生态类食物百分组成 ,棕贼鸥 (C .s.lonnbergi)占 63.4% ,灰贼鸥 (C .maccormic ki)占 77.8%。同期 ,取自考察站的人类废弃物中垃圾食物的百分组成分别为 36.6%和 2 2 .3%。贼鸥食性对考察站废弃物有一定的依赖性 ,与本区环境质量下降 ,尤其考察站对废弃物的疏于管理有着直接的关系。由此表明 ,强化南极考察人员环境意识 ,建立封闭式废弃物管理系统 ,对保护南极环境有重要意义  相似文献   

Economic assessment of production of flour from Prosopis alba and P. pallida pods for human food applications.     

Peter Felker  Nora Grados  Gaston Cruz  Dante Prokopiuk 《Journal of Arid Environments》2003,53(4):517-528

This paper presents a detailed cost accounting of the processes involved in the production of flours from the mesocarps of the fruits of Prosopis alba and P. pallida to be used in human foods. The flours from both species are similar and contain 7–8% protein, 0·8–2% fat, 26–32% total dietary fiber and 48–59% sucrose. The data were based on actual production rates in use at the Universidad de Piura pilot plant using simple machinery. Machinery hourly charges were based on equivalent rental costs in order to avoid interest charge calculations. As opposed to other analyses which only included processing costs delivered to the plant, our analysis ascribed value to the owner of the trees in order to provide incentives to plant and care for the trees. The sensitivity analyses showed that the most economically important factor was the conversion efficiency of pods into flour. When a 40% conversion efficiency, such as that which has been obtained in both Peru and Argentina was obtained, and by-product credits for high fiber containing fraction were assumed, the wholesale selling price with a 5% marketing cost and a 40% profit direct costs was estimated to be $0·66 kg⁻¹ for Peru (using a $0·40 h⁻¹ labor rate ) and $1·76 kg⁻¹ for Argentina (using a $1·5 h⁻¹ labor rate).  相似文献   

碧口群火山岩的时代——SHRIMP锆石U—Pb测年结果   总被引：12，自引：0，他引：12  

闫全人  王宗起闫臻 AndrewD.Hanson PeterA.Druschke刘敦一  宋彪简平 王涛 《地质通报》2003,22(6):456-458

碧口群火山岩系是从原碧口系(叶连俊等,1944,后称碧口群)中解体出来的一个岩石单元(陶洪祥等,1993)。虽经过近60年的研究,但对某些关键问题,特别是碧口群火山岩系的时代,仍存在不同认识。在早期研究阶段(20世纪40～50年代)和60～70年代的区域地质调查工作中,碧口群和横丹群被视做一个整体,并通过地层层序关系探讨其时代。如,叶连俊等(1944)提出碧口系形成于志留—泥盆纪,黄振辉(1959)则认为碧口群属寒武—志留系。80年代以来对碧口群火山岩系进行的同位素年代学和地古生物学研究给出了从新元古代(赵祥生等,1990;胡正东,1990;李耀敏,1991;秦…  相似文献   

Flow and fracture maps for basaltic rock deformation at high temperatures     

Valentina Rocchi  Peter R. Sammonds  Christopher R.J. Kilburn   《Journal of Volcanology and Geothermal Research》2003,120(1-2):25-42

Understanding how the strength of basaltic rock varies with the extrinsic conditions of stress state, pressure and temperature, and the intrinsic rock physical properties is fundamental to understanding the dynamics of volcanic systems. In particular it is essential to understand how rock strength at high temperatures is limited by fracture. We have collated and analysed laboratory data for basaltic rocks from over 500 rock deformation experiments and plotted these on principal stress failure maps. We have fitted an empirical flow law (Norton’s law) and a theoretical fracture criterion to these data. The principal stress failure map is a graphical representation of ductile and brittle experimental data together with flow and fracture envelopes under varying strain rate, temperature and pressure. We have used these maps to re-interpret the ductile–brittle transition in basaltic rocks at high temperatures and show, conceptually, how these failure maps can be applied to volcanic systems, using lava flows as an example.  相似文献   

Imaging buried Quaternary valleys using the transient electromagnetic method   总被引：3，自引：0，他引：3  

Flemming Jrgensen  Peter B. E. Sandersen  Esben Auken 《Journal of Applied Geophysics》2003,53(4):199

Buried Quaternary valleys in Denmark are complex structures filled with various deposits consisting primarily of glacio-lacustrine clay, till and meltwater sand, and gravel. The valleys are important geophysical targets, because they often contain significant volumes of groundwater used for public water supply. About 700 km of buried valley structures have been imaged in the western part of Denmark by the transient electromagnetic (TEM) method. The ability to map the valleys depends primarily on valley geometry, infill architecture and the resistivity of the fill sediments as well as the substratum. One-dimensional (1-D) inversion models of the TEM soundings have been used to construct contour maps of 20 m average resistivities and depth to a good conductor, which provide images for geological interpretation. Images of buried valley morphology, fill properties, infill architecture, such as cut-and-fill structures, valley distribution and valley generations, are characterized for case studies from Hornsyld, Holstebro and the Vonsild/Agtrup areas of Denmark.  相似文献