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891.
POSINGTHEPROBLEM“ComplexityandSelf-OrganizedCriticalityofSolidEarthSystem”isanewproblemaswelasanewproposition.Theauthorputsfo...  相似文献   
892.
从同位素到板块构造:化学地球动力学   总被引:3,自引:0,他引:3  
化学地球动力学是地球化学的分支学科,它在研究地球内部化学组成和演化时,把地球视为一个完整的动力学系统而不是彼此孤立的地质集合体。通过研究地球各层圈内部的化学结构和过程以及不同层圈之间的化学相互作用,从本质上研究和认识发生在地球内部的各种地质作用。文中概括了化学地球动力学的特点和突出成果,分析了化学地球动力学研究的科学意义,并对在中国开展壳幔相互作用的化学地球动力学研究提出了建议。  相似文献   
893.
张福祯 《化工矿产地质》1998,20(4):325-327,330
改革开放以来,全国地勘行业发生了深刻变化,取得了一定成绩,但也存在一些问题。有的固体矿产普查项目面积过大,工程间距过稀,致使普查任务难以完成。控制固体矿产普查区面积不宜过大,以满足“三线(勘探线)两点(探矿工程)”的布设为宜。普查区内工程的布置要达到总体控制,亦即该矿种该勘探类型C级储量控制网度放稀一倍。  相似文献   
894.
Diatom remains were analysed in two short sediment cores from a subalpine Italian lake (Lake Orta), known for its major industrial pollution dating from the late 1920s, which has only recently been stopped. Copper was recognised as the main toxic agent for diatoms during the first 30 years of pollution (peak value: 100 g l-1 in the late 1950s). A diatom community similar to other deep subalpine lakes existed in the past, and was disrupted by the pollution events. Acute and long-term effects of Cu contamination were tracked by changes in three distinct groups of species around the sharp boundary corresponding to the onset of the pollution. These groups were respectively composed of: (1) Species quickly extirpated by the discharge, mostly belonging to Fragilaria and Cyclotella and never reappearing; (2) Species apparently not affected, or not immediately affected, by the pollution, showing no definite trends with time. Synedra species, with various deformities, were conspicuous among these; (3) Species with accumulation rates increasing with time irrespective of pollution, mostly belonging to Achnanthes. Properties and tolerances of these groups (e.g. Synedra and Achnanthes) are discussed in detail.  相似文献   
895.
中国北方海岛县经济区及其划分的初步研究*   总被引:7,自引:2,他引:5  
张耀光 《地理研究》1998,17(3):289-288
在我国海岛县经济类型(或类型区)划分的基础上,划分出我国海岛经济区的框架,以我国北方海岛县经济区为重点,探讨海岛经济区的划分方法,提出发展方向与对策。  相似文献   
896.
广东云浮硫铁矿矿床多因复成富集机制   总被引:1,自引:0,他引:1  
从历史-因果论出发,运用陈国达教授提出的多因复成成矿理论,对广东云浮硫铁矿的成矿作用重新进行了研究和解剖。首次研究并论证了矿床形成的裂谷背景,提出了本矿床是一种经历了晚元古代裂谷期海底喷流初始沉积,加里东期裂谷回返动力变质过程中的矿体塑性流动和剪切固态迁移集中富集(有混染了的变质热液的叠加),印支或岩浆热液叠加富化的多因复成矿床的新观点。  相似文献   
897.
BOOK REVIEWS     
Book Reviewed in this article: Geography and the Third World. International Seminar, 14–18 May 1980, Kuala Lumpur, Malaysia . Ishmail Ahmad and Jamaluddin Md Jahi, eds. The Growth Dilemma: Residents' Views and Local Population Change in the United States . Mark Baldassare. Sport and Place: A Geography of Sport in England, Scotland & Wales . John Bale. The Deindustrialization of America: Plant Closings, Community Abandonment, and the Dismantling of Basic Industry . Barry Bluestone and Bennett Harrison. Selected Essays 1963–1975: Carl O. Sauer . Bob Callahen, ed. Housing and Planning in the Countryside . G. Clark. Conflict, Politics and the Urban Scene . Kevin R. Cox and R. J. Johnston, eds. Thematic Maps: Their Design and Production . David J. Cuff and Mark T. Mattson. Wine: A Geographic Appreciation . Harm Jan de Blij. USSR in Maps . J. C. Dewdney. Political Geography: A Contemporary Perspective . Ramesh D. Dikshit. Rethinking Human Adaptation . Rada Dyson-Hudson and Michael A. Little, eds. Sacred Sands: The Struggle for Community in the indiana Dunes . J. Ronald Engel. Geography of the Biosphere . A. Furley and Walter W. Newey. Disaster and Reconstruction . Robert Geipel. Glasgow: The Making of a City . Andrew Gibb. Design for Arid Regions . Giden S. Golany, ed. Urbanization and Cancer Mortality: The United States Experience, 1950–1975 . Michael R. Greenberg. Geology in the Nineteenth Century: Changing Views of a Changing World . Mott T. Greene. Colonización y Destrucción de Bosques en Panamá . Stanley Heckadon Moreno and Alberto McKay, eds. Urban Geography: A First Approach . David T. Herbert and Colin J. Thomas. The Visual and Spatial Structure of Landscapes . Tadahiko Higuchi. Climate from Tree Rings . M. K. Hughes, P. M. Kelly, J. R. Pilcher, and V. C. LaMarche, Jr., eds. The structure of Nineteenth Century Cities . James H. Johnson and Colin G. Pooley, eds. The American Planner: Biographies and Recollections . Donald A. Krueckeberg, ed. Urban Land Policy For the 1980s, the Message for State and Local Government . George Lefcoe, ed. Regional Planning: Evolution, Crisis and Prospects . Gill C. Lim, ed. Relevance and Ethics In Geography . Bruce Mitchell and Dianne Draper. China: The Geography of Development and Modernization . Clifton W. Pannell and Laurence J. C. MA. The Urban Retailing System . Robert B. Potter. Hants. Nonconventional Energy Resources . Philip R. Pryde. Caribbean Migrants: Environment and Human Survival on St. Kitts and Nevis . Bonham C. Richardson. Population and Resources . Harry Robinson. East Los Angeles: History of A Barrio . Ricardo Romo. Integrated Impact Assessment . Frederick A. Rossini and Alan L. Porter, eds. Environmental Aesthetics: Essays in Interpretation . Barry Sadler and Allen Carlson, eds. Earthwatch . Charles Sheffield. Field Techniques and Research Methods in Geography . Robert H. Stoddard. Haiti: Land of Poverty . Robert J. Tata. Weathering and Erosion: Sources and Methods in Geography . Stephen T. Trudgill. Once Beneath the Forest. Prehistoric Terracing in the Río Bec Region of the Maya Lowlands . B. L. Turner, II. The Historical Geography of Scotland since 1707 . David Turnock.  相似文献   
898.
论产业集群的知识协作机制   总被引:11,自引:0,他引:11  
产业集群的知识协作机制包括:信任机制和知识共享机制。其信任机制表现为:集群信任的形成是企业个体(或私人)的内在利益诉求的必然结果,也是集群环境下市场选择与市场竞争监督的“社会实施”的产物;其知识共享机制表现为:集群的空间集聚与信任特征创造了“面对面交流”的有利条件,集群的社会文化特征促进集群整体默会性知识的扩散与共享,集群的网络特征加速知识外溢与创意流动,为群内企业工作人员的知识开发与创造构筑协作平台。  相似文献   
899.
BOOK REVIEWS     
Book Reviewed in this article: Portable Utopia: Glasgow and the United States 1820–1920. Bernard Aspinwall. Studies in Russian Historical Geography. James H. Bater and R. A. French, eds. Water and Sanitation: Economic and Sociological Perspectives. Peter G. Bourne, ed. Green Politics. Fritjof Capra and Charlene Spretnak. The Southern Cone: Realities of the Authoritarian State. César N. Caviedes. Women in Third World Development. Sue Ellen Charlton. Land Management: New Directions. David Chiddick and Alan Millington, eds. Geography and Ethnic Pluralism. Colin Clarke, David Ley, Ceri Peach, eds. Geomorphological Hazards in Los Angeles. R. U. Cooke. Regional Impacts of United States-Mexico Economic Relations. Alfonso Corona and Lay James Gibson. eds. Patterns of Jobs and Geographic Mobility. Torvald Gerger. Cities and Sickness: Health Care in Urban America. Ann Lennarson Greer and Scott Greer, eds. Neighborhoods: Their Place in Urban Life. Howard W. Hallman. Development and the Rural-Urban Divide. John Harriss and Mick Moore, eds. Patterns of Undocumented Migration: Mexico and the United States. Richard C. Jones, ed. Central Place Theory. Leslie J. King. The Geography of Western Europe: A Socio-economic Survey. Paul L. Knox. Regions and Resources: Strategies for Development. David T. Krisge, Daniel A. Seiver, Oliver S. Goldsmith and Michael J. Scott. Geography of Crowding and Human Response. A Study of Ahmedabad City. K. M. Kulkarni. Haciendo Pueblo. The Development of a Guadalajaran Suburb. Kathleen Logan. The Imperial Lion: Human Dimensions of Wildlife Management in Central Africa. Stewart A. Marks. Water in the Hispanic Southwest: A Social and Legal History, 1550–1850. Michael C. Meyer. Imlil: A Moroccan Mountain Community in Change. James A. Miller. Tourism in Canada: Selected Issues and Options. Peter E. Murphy, ed. David Harvey's Geography. John L. Paterson. Raster Scanning, Processing and Plotting of Cartographic Documents. Donna J. Peuquet and A. Raymond Boyle. The USSR and the Muslim World: Issues in Domestic and Foreign Policy. Yaacov Ro'i, ed. Environmental Perception and Behavior: An Inventory and Prospect. Thomas F. Saarinen, David Seamon, and James L. Sell. Incised channels, Morphology, Dynamics, and Control. Stanley A. Schumm, Michael D. Harvey, and Chester C. Watson. The Gap Between Rich and Poor: Contending Perspectives on the Political Economy of Development. Mitchell A. Seligson, ed. Twentieth-Century Richmond. Planning, Politics and Race. Christopher Silver. Land Conservation and Development: Examples of Land-Use Planning Projects and Programs. F. R. Steiner and H. N. van Lier, eds. Biogeography: Recent Advances and Future Directions. J. A. Taylor, ed. Late Quaternary Environments of the Soviet Union. A. A. Velichko, ed. H. E. Wright, Jr. and C. W. Barnosky, eds.  相似文献   
900.
South African industrial fisheries have been dominated by a few large companies. The Marine Living Resources Act (MLRA) of 1998 emphasised that equity was to be achieved by redistribution through co-operative strategies among stakeholders. Instead, the reallocation of fishing rights has been treated as a resource management issue rather than a socio-economic challenge. Further, the institutional structures for transformation have been inappropriate. This paper investigates the institutional dynamics and discrepancies associated with transformation and concludes that the process became locked in a path dependency, which will eventually undermine the intentions of transformation.  相似文献   
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