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151.
2002年春季吕宋海峡海流观测及其谱分析 总被引:1,自引:0,他引:1
基于2002年春季航次在吕宋海峡海域锚碇测流站(20°49'57"N,120°48'12"E)200,500与800m锚碇测流水层观测流,进行的海流特征分析与最大熵方法谱分析,得到以下主要结果.(1)在200m处,观测期间海流平均速度为(47.4cm/s,346°),最大观测海流速度Vmax和最大日平均海流速度Vd,max分别为(103.8cm/s,10°)和(71.6cm/s,339°);在500m处,观测期间平均流速为(20.3cm/s,350°),最大观测海流速度Vmax和最大日平均海流速度Vd,max分别为(74.1cm/s,17°)和(39.1cm/s,317°).这些都表明黑潮在吕宋海峡锚碇测流站200和500m处向西北方向入侵南海.(2)在800m处,观测期间平均流速为(1.2cm/s,35°),最大观测海流速度Vmax和最大日平均海流速度Vd,max分别为(10.8cm/s,76°)和(4.7cm/s,46°).这些都表明,它们的流向皆为东北向.比较在每层实测流的结果,表明在800m层海流状况与200和500m层海流状况是不相同的,流速随深度变深明显减弱,流向向右偏转.(3)在观测期间200,500和800m处,日平均流速在4月皆比3月时要强.(4)在200~800m潮流随深度变深有所变化,除了在500m处f<0情况全日潮峰值高于半日潮峰值以及对于半日潮以逆时针方向为主以外,其余情况在200~800m水层半日潮峰值都要高于全日潮的峰值,并且皆以顺时针方向旋转为主.(5)在200~800m水层都存在15d以上或14d左右的周期振动,例如在逆时针方向分量谱(f>0)在200,500m处存在19d左右的周期振动;在800m处存在14d左右的周期振动(f<0).(6)在200~800m处都存在4~6d周期天气过程的振动和2~3d周期振动.还都存在34.5h左右惯性振动周期,它的振动方向为顺时针方向.(7)通过交叉谱的计算,揭示:1)200与500m层两组流速时间序列对于半日潮周期、全日潮周期、15d以上的周期振动、2~3d的周期振动等都有很好的相关性,且对15d以上的长周期振动几乎是同步的;2)500与800m层两组流速时间序列对于4~6d天气过程的周期振动与2~3d的周期振动等都有很好的相关性,但它们之间有相位差,有滞后或提前现象. 相似文献
152.
文章首先指出“测量学”课程在测绘科学知识体系中起着奠基性的作用,而教材建设是“测量学”课程教学改革中的一项重要的基础性工作。然后,在简要分析现行“测量学”教材中存在的问题的基础上,分别从“测量学”教材的定位、名称、内容体系等几个方面提出几点思考意见供同行参考。 相似文献
153.
基于卓越工程师培养诉求的教学改革的理性思考——面向CDIO理念的地图学教改构想 总被引:3,自引:1,他引:2
文章根据卓越工程师的培养诉求,基于科学发展观,对地图学的教学现状进行了反思,对改革进行了构想,确立了"强化内涵"、"巩固外延"、突出"特色资源"的教改思路.提出了教学中要努力实现师生关系"人性化"、教学手段"现代化"、教学内容"科学化"、教学方式"多样化"、实践教学"工程化"、评价体系"客观化"的教改设想.作者认为教学... 相似文献
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Ecosystem-based marine spatial management: Review of concepts, policies, tools, and critical issues 总被引:1,自引:0,他引:1
Stelios Katsanevakis Vanessa Stelzenmüller Andy South Thomas Kirk Sørensen Peter J.S. Jones Sandy Kerr Fabio Badalamenti Christos Anagnostou Patricia Breen Guillem Chust Giovanni D’Anna Mike Duijn Tatiana Filatova Fabio Fiorentino Helena Hulsman Kate Johnson Aristomenis P. Karageorgis Ingrid Kröncke Simone Mirto Carlo Pipitone Susan Portelli Wanfei Qiu Henning Reiss Dimitris Sakellariou Maria Salomidi Luc van Hoof Vassiliki Vassilopoulou Tomás Vega Fernández Sandra Vöge Anke Weber Argyro Zenetos Remment ter Hofstede 《Ocean & Coastal Management》2011,54(11):807-820
Conventional sectoral management and piecemeal governance are considered less and less appropriate in pursuit of sustainable development. Ecosystem based marine spatial management (EB-MSM) is an approach that recognizes the full array of interactions within an ecosystem, including human uses, rather than considering single issues, species, or ecosystem services in isolation. Marine spatial planning and ocean zoning are emerging concepts that can support EB-MSM. EB-MSM is driven by high-level goals that managers aim to achieve through the implementation of measures. High-level goals and objectives need to be translated into more operational objectives before specific targets, limits and measures can be elaborated.Monitoring, evaluation and adaptation are necessary to ensure that marine management measures are both effective and efficient. Solid monitoring frameworks are the foundation of adaptive management, as they provide the necessary information to evaluate performance and the effectiveness of management actions. Marine protected areas (MPAs) - possibly set up in networks - constitute a key component in EB-MSM policies and practises and have been applied as a cornerstone in conservation of marine biodiversity, management of fish populations, development of coastal tourism, etc. Moreover, MPA experiences have provided methods and concepts (such as zoning) to a wider EB-MSM context. The assignment of values to biophysical features of the marine environment allows the direct assessment of related management choices and may assist EB-MSM.A range of monetary valuation techniques have been proposed to reduce attributes of goods and services to a single metric. However, in the marine environment such an approach is often over simplistic, and thus less reductive techniques may be necessary. Rather than producing a single metric, the results of non-monetary assessments guide policy allowing weight to be given as necessary to potential areas of conflict and consensus.Strategies to take into account climate change effects and geohazard risks in EB-MSM have been applied or proposed worldwide. EB-MSM regimes must be alert to such risks and flexible to account for changes. 相似文献
156.
《The Professional geographer》1986,38(2):195-222
Book Reviewed in this article: The Vanishing Farmland Crisis, Critical Views of the Movement to Preserve Agricultural Land . John Baden Protecting Farmlands . Frederick R. Steiner and John E. Theilacker Ecological Effects of Fire in South African Ecosystems . Peter de V. Booysen and Neil M. Tainton Geography in China . Wu Chuanjun , Wang Nailiang , Lin Chao and Zhao Songqiao Resource Inventory and Baseline Study Methods for Developing Countries . Francis Conant , Peter Rogers , Marion Baumgardner , Cyrus Mc Kell , Raymond Dasmann, and Priscilla Reining Principles of Remote Sensing . Paul J. Curran Famine As A Geographical Phenomenon . Bruce Currey and Graeme Hugo The Suburban Squeeze: Land Conversion and Regulation in the San Francisco Bay Area . David E. Dowall Senses of Place . John Eyles Uneven Development and the Geographical Transfer of Value . D. K. Forbes and P. J. Rimmer Issues in Wilderness Management . Michael Frome Land-use and Prehistory in South-east Spain , The London Research Series in Geography 8. Antonio Gilman and John B. Thornes with Stephen Wise Regions in Question, Space, Development Theory and Regional Policy . Charles Gore The Colorado River: Instability and Basin Management . William L. Graf Hazardous Waste Sites: The Credibility Gap . Michael R. Greenberg and Richard F. Anderson Peasants, Subsistence Ecology, and Development in the Highlands of Papua New Guinea . Lawrence S. Grossman Silver Cities: The Photography of American Urbanization, 1839-1915 Peter B. Hales Silicon Landscapes . Peter Hall and Ann Markusen Remaking Ibieca: Rural Life in Aragon under Franco . Susan F. Harding The European Energy Challenge: East and West . George W. Hoffman The Global Climate . John T. Houghton The Urban Jobless in Eastern Africa . Abel G. M. Ishumi . The Tourist: Travel in Twentieth-Century North America . John A. Jakle City and Society: An Outline for Urban Geography . R. J. Johnston Residential Segregation, The State and Constitutional Conflict in American Urban Areas . R. J. Johnston Accessibility and Utilization: Geographical Perspectives on Health Care Delivery . Alun E. Joseph and David R. Phillips To the Heart of Asia: The Life of Sven Hedin . George Kish North American Culture , Vol 1. Ary J. Lamme III Past and Present in the Americas: A Compendium of Recent Studies . John Lynch Ethnicity in Contemporary America: A Geographical Appraisal . Jesse O. Mc Kee The Shell Countryside Book . Richard Muir and Eric Duffey 1990 Planning Conference Series. Proceedings of the National Geographic Areas Conference . Proceedings of the Regional Geographic Areas Conferences Wood, Brick, and Stone: The North American Settlement Landscape . Vol. 2: Barns and Farm Structures . Allen G. Noble Bangladesh: Biography of a Muslim Nation . Charles Peter O'donnell 相似文献
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