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流域交通运输地理在区域交通运输地理的理论框架下,以流域或流域的部分区域为研究区开展交通运输组织及其发展规律研究。论文从交通网络、运输联系及区域效应3个方面梳理了流域交通运输地理的研究进展。 ① 交通网络相关研究围绕综合交通发展水平与格局、网络连接特征与可达性、港口体系的空间结构与供应链等展开,多式联运正成为流域交通运输地理研究的新热点;② 运输联系主要研究客货运输联系规律和交通流,流域物流地理的研究重点正从物流产业布局与企业选址向物流网络与空间组织、物流供应链转移;③ 区域效应偏重于经济增长效应,资源环境生态效应研究较为薄弱。基于流域交通运输地理研究的侧重点,结合当前研究进展与流域发展需求,流域交通运输地理学未来应重视流域港口体系与水运发展,关注综合交通网络构建与运输组织以及多式联运,探究不同层级流域交通运输间的关联性,同时应加强流域交通运输的资源环境与生态效应研究。 相似文献
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稳态风沙流中瞬态输沙特征 总被引：1，自引：0，他引：1
风沙流中沙粒运动在来流风速不变时也会表现出非稳态特征。在风洞内利用粒子图像测速系统（PIV）测量了风沙运动的时间序列,并基于PIV测量技术提出风沙流中沙粒平均直径、数密度、平均水平速度和输沙通量等参数在某一时刻的计算方法,其中输沙通量的计算考虑沙粒大小垂向分布的影响。结果表明：来流风速不变时,沙粒平均直径、数密度、平均水平速度和输沙通量随时间具有明显的波动性;沙粒平均直径和平均水平速度的标准偏差一般随高度增加而增加,沙粒数密度和输沙通量标准偏差随高度增大而减小;这些参数的相对标准偏差均随高度增加而增大。 相似文献
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D.C. Johnston 《Singapore journal of tropical geography》2007,28(2):171-187
Public passenger transport services receive relatively little space in the literatures on rural transport in developing economies, which mostly focus on the provision, or socioeconomic impacts, of roads. The implication is either that rural people are able to purchase or have access to motorized transport – or that they can walk on thoroughfares intended for vehicles. Statistics from Indonesia show that a low proportion of rural households own motor vehicles, but that rural bus services have seen a substantial expansion since the late 1970s; however, the coverage of the rural population is not complete. Based on survey data from villages ( desa ) in West Java, Indonesia, this paper explores several issues with respect to bus operations and motorcycle taxi ( ojek ) services in rural areas: the nature of public passenger services, the users of those services and the nature of trips made. 相似文献
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本文从河口塑造与输沙关系、流域泄沙与输移模式,以及口外来沙与潮流输移特征等三方面,探讨河口区的泥沙运移规律和补给来源。并在此基础上,提出粗细不同粒级的造床泥沙按不同方式治理的设想。 相似文献
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瓯江河口输沙模式与应用研究 总被引：2，自引：1，他引：2
本文从河口塑造与输沙关系、流域泄沙与输移模式,以及口外来沙与潮流输移特征等三方面,探讨河口区的泥沙运移规律和补给来源。并在此基础上,提出粗细不同粒级的造床泥沙按不同方式治理的设想。 相似文献
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Hongbo Yu 《The Professional geographer》2013,65(3):435-437
Books reviewed: D. Graham Burnett, Masters of All They Surveyed: Exploration, Geography, and a British El Dorado Garrett A. Sullivan, Jr., The Drama of Landscape: Land Property and Social Relations on the Early Modern Stage Sergio Díaz-Briquets and Jorge Pérez-López, Conquering Nature: The Environmental Legacy of Socialism in Cuba Karl F. Nordstrom, Beaches and Dunes of Developed Coasts Robin W. Doughty, The Eucalyptus: A Natural and Commercial History of the Gum Tree James K. Mitchell, ed., Crucibles of Hazard Gerald T. Koeppel, Water for Gotham: A History Arnold R. Alanen and Robert Z. Melnick, eds., Preserving Cultural Landscapes in America Kavita Pandit and Suzanne Davies Withers, eds., Migration and Restructuring in the United States Steven R. Nivin, Regional Innovation Potential: The Case of the U.S. Machine Tool Industry Douglas Meyer, Making the Heartland Quilt: A Geographical History of Settlement and Migration in Early Nineteenth-Century Illinois David R. Meyer, Hong Kong as a Global Metropolis Mark Cleary and Goh Kim Chuan, Environment and Development in the Straits of Malacca David Zurick and P. P. Karan, Himalaya: Life on the Edge of the World Christer Jönsson, Sven Tägil, and Gunnar Törnqvist , Organizing European Space Tor Bernhardsen, Geographic Information Systems: An Introduction, 2nd ed. 相似文献
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中国区域交通优势的甄别方法及应用分析 总被引：67，自引：9，他引：58
一个区域的交通优势反映在“质”、“量”和“势”三个方面, 每个方面具有相对独立而具体的内涵, 对区域社会经济的发展具有不同的作用, 其中任一方面的刻画和评价仅仅反映区域交通优劣的一个侧面, 只有三方面的综合集成刻画与评价才能真正反映一个区域交通环境的优劣。基于交通地理学的基本理论, 界定了交通优势度的基本概念, 并建立了交通优势度的基本表述结构, 包括交通网络密度、交通干线影响度和区位优势度; 同时基于GIS 技术, 从分项和综合集成两个角度构筑了交通优势度评价的空间数理模型。以我国2365 个地域 单元为样本的实证分析发现, 我国的区域交通优势度呈“偏正态”分布特征, 极少数的地域 (比例为1.4%) 具有非常突出的交通优势, 社会经济发展具有非常优越的交通环境; 大约1/8 的地域(12.4%) 交通条件处于非常明显的劣势, 交通环境是其社会经济发展的不利条件; 大约70%地域处于评价样本的中游或中游偏上水平。从区域上看, 交通优势大致由沿海逐渐向内陆依次递减; 长江三角洲、京津冀、珠江三角洲三大城镇密集区有着明显的交通优势, 覆盖范围广; 成渝地区和武汉都市圈也有较好的交通优势, 但尚未连续成面或覆盖范围较小, 其他城镇密集区和省会城市周边地区有相对较高的交通优势, 但覆盖地域较小。从经济发展措施看, 利用交通优势和规避交通劣势, 应是进行经济活动和产业选择需要考虑的重要因素。 相似文献
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黄河下游泥沙输移数值模拟 总被引：2，自引：0，他引：2
本文从数学模型入手,探讨黄河下游在多年平均来水来沙条件下,泥沙输移与泥沙淤积的特性,得出黄河下游泥沙沿程淤积分布不均匀主要是由于粗沙、中沙沿程淤积不均匀造成的,如果使来沙减少42.6%,黄河下游可望达到冲淤平衡. 相似文献
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Recent viewpoints concerning the state of research in transport geography have touched on the issue of insularity and the need to bridge the divide between the largely spatial–analytical or quantitative research in transport geography and the critical or qualitative research prevalent in urban, economic, and most other subfields of human geography. Transport geography has been criticized by some for being a quiet corner of our discipline that has lost its centrality largely because it remains within the analytical framework of the 1960s. This article explores these sentiments by reexamining recent transport-oriented research in highly cited geography journals to assess the degree to which the qualitative–quantitative divide exists within transport geography and between transport and other subfield in human geography, as well as to explore issues of productivity and centrality of transport-oriented research in geography. Results indicate that geographical research involving transport topics is much more prevalent and reflects a wider range of epistemological and methodological approaches than is frequently assumed. Nevertheless, there is still a considerable divide between “mainstream” transport geography and other human geographical research that necessitates much more interaction between transport and other subfields and greater incorporation of alternative research approaches within the mainstream of transport geography. To that end, we propose a preliminary critical transport geography research agenda that is open to a variety of methodological approaches, including quantitative analysis. 相似文献
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空间运输联系的生成与增长规律研究 总被引：29，自引：2，他引：29
空间运输联系是指在自然、社会、经济诸要素综合作用下，区域间通过交通运输设施进行旅客和货物的交流。区域差异与互补是空间运输联系产生的直接原因，交通设施是空间运输联系实现的基础。本文以世界不同类型国家和我国近半个世纪的运输活动及其社会经济背景值作为研究对象，采用定量与定性相结合的实证分析方法，经过归纳、演绎和推理，深入研究了运输联系生成的内在机制和增长演变的趋势，得出了旅客生成密度和客运强度随经济增长而增长、货物生成密度和货运强度随经济增长而降低的结论。在评价指标方面，提出了生成密度、运输强度等概念和指标，并对世界主要国家的运输发展进行了对比分析。 相似文献
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《自然地理学》2013,34(5):366-380
The local topography of a landscape can have a profound influence on airflow characteristics and cause modifications to broader synoptic scale winds. This paper reports the results of a preliminary field study examining the effects of a valley on wind velocity and direction. Anemometers and wind vanes were used to measure airflow characteristics upwind, within and downwind of a 20 m deep and 175 m wide dry valley in the central Namib desert. The field data indicate an upwind region of flow acceleration, a minimum in flow velocity in the center of the valley, flow acceleration toward a maximum at the downwind valley edge and subsequent deceleration toward starting velocities downwind of this edge. The development of a flow separation region at the leading edge of the valley and the range of flow distortion are affected by the incident angle of the approaching wind to the axis of the valley. A conceptual model indicating the potential implications of these findings for aeolian sediment transport processes in the vicinity of dryland valleys is presented. 相似文献
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Ye Qingchao 《地理学报(英文版)》1995,(1)
TheYelowfover,risingintheYawiiebasinatthenofthofBayanthrMts.onTibanPatheu,istheseCOnlaperiverinChina.ItflowseaStWrdthrowtnineprownasorngonsof~i,Sichuan,Gansu,Ningha,InnerMonghia,Sbo,Shaaha,Ham,andShanwtintotheBohaiSeaatKedicoUnty,ShandongProvince.Itcovers… 相似文献
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大气——植被——土壤之间物质和能量输送过程与机制的分析 总被引：8，自引：0，他引：8
在绿洲－荒漠交界处，由于绿洲荒漠之间的相互影响，相互作用，使得大气－植被－土壤之间的特和能量交换形成其特有的过程，本文对这些交换过程与机制进行了较为详细，准确的讨论。 相似文献
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80年代以来我国区域旅客生成特征分析 总被引：1，自引：0，他引：1
我国改革开放以来旅客运输迅速发展,空间分布格局发生了重要变化,与我国区域社会经济发展有着十分密切的关联.利用空间运输联系理论和实证分析方法,对于旅客生成特征、区域差异及其原因进行的分析表明:20世纪80年代以来全国以及各地区的旅客生成密度大幅度增长.同时,省级区域旅客生成密度分布格局发生了明显的变化;省级区域旅客生成密度的相对差距20世纪80年代上升、90年代有所下降;高客运密度区从相对均衡分布变为向南方区域倾斜.这种变化的主要影响因素有三:经济增长、人口流动和交通网发展. 相似文献
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l.TheNewTowllsofHongKo11gInanattempttotestifytheintimateandvitalrelationshipbetweennewtownsandthemetroPOlitanarea,andtheil1teractingrolesbetweentheplanningandprovisionofpublictransPOrtfacilitiesontheonehand,andthechangingfunctionsofnewtownsontheother,thispaperpresentssomeexperiencegainedinastudyofnewtowntransportplaninnginHongKong.HongKonghasatotallandareaofabout1o74kinandwasinhabitedbyabout5.9millionPeopleinl992.About77percentofthemlivedinthemetroPOlitanarea.TheeconomicsystemofHongKong… 相似文献
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Wind forces and related saltation transport 总被引：7，自引：1，他引：7
The effect of several wind characteristics on sand transport was studied in three experiments in north Burkina Faso, West Africa. The first experiment is used to analyse the relation between wind speed and shear stress fluctuations across height. The second experiment is used to study the relation of these wind characteristics with saltation transport for fourteen convective storms, registered during the rainy seasons of 2002 and 2003. The effect of sampling time is studied for two of these convective storms. The third experiment relates the turbulent structures of four convective storms to saltation transport. Wind speed measurements were undertaken with two sonic anemometers and sediment transport was measured by two saltiphones. The sampling frequency was either 8 or 16 Hz. The sonic frame of reference was rotated according to a triple rotation.Horizontal fluctuations showed a (fairly) good correlation with height because the wind speed at both sensors was affected by the same vortices. The correlation coefficients ranged from 0.42 (when the distance between the sensors was 1.75 m) to 0.92 (when the distance was 0.25 m). The instantaneous Reynolds' stress had the weakest correlation (correlation coefficient of 0.05 at 1.75 m between the sensors and 0.56 at 0.25 m between the sensors), because the momentum at 2 m above the soil surface is transported by different eddies than those close to the ground. This also explains the fairly good correlation coefficients between the horizontal components of the wind and saltation compared to the poor correlations between instantaneous Reynolds' stress and saltation. An increase in sampling time did not have much impact on these correlation coefficients up to sampling periods of about 30 s. However, this sampling interval would be too coarse to describe the vertical wind component adequately. The classification of the moments of shear stress into the turbulent structures, sweeps, ejections, inward and outward interactions, showed that the mean saltation flux is higher at sweeps and outward interactions than at ejections and inward interactions. Also, saltation occurred more often during sweeps and outward interactions than during ejections and inward interactions. 相似文献