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991.
形态学图像处理方法在扎龙湿地景观格局分析中的应用 总被引:1,自引:0,他引:1
以数学形态学图像处理技术为主要方法,对扎龙湿地景观格局进行分类,形成核心、斑块、边缘和孔隙4种格局类型,并在此基础上与土地覆盖类型图叠加处理,分析湿地不同景观格局与土地覆盖类型的关系。结果表明,基于形态学图像处理技术的景观格局分类保持了像元水平的精度,优于传统的分类方式。1979-2008年,扎龙湿地的核心湿地减少,斑块、边缘和孔隙都相应增加。作为湿地中的优势类型,含地表水的湿地逐渐转移到非核心的斑块、边缘和孔隙湿地中,原有的核心湿地逐渐变得破碎。 相似文献
992.
本文利用1987、1997和2007年遥感数据,结合野外调查,以玉树藏族自治州为例,研究20年来景观空间格局的时空变化特征。结果表明,研究区草地景观面积减少,农田和荒地增加;草地斑块的分布越来越分散,斑块面积减小。草地和森林植被是玉树藏族自治州主要的植物资源景观,草地的连通性比较高;人为干扰和气候的变化是研究区景观时空变化的主要原因。研究结果为该区域生态保护对策的制定和环境的可持续发展管理提供了理论依据和技术的指导。 相似文献
993.
泾河流域是农业旱灾的多发地区,但是对该地农业旱灾的发生规律、旱灾影响及旱灾恢复和准备措施方面开展的研究还较少。本文根据自然灾害风险评估的理论框架,建立了1km栅格精度的泾河流域农业旱灾风险空间评估模型,并对农业旱灾致灾因子危险性及农业承险体脆弱性进行评估,最后综合评估该地区农业旱灾风险。在此基础上,分析研究区农业旱灾危险性、承险体脆弱性及风险的空间特征。本研究采用Z指数方法评估泾河流域农业旱灾致灾因子的强度,选取农作物生长季缺水率、土壤有效含水量、有效灌溉面积比以及坡度等4个指标评估研究区1km空间尺度的农业旱灾脆弱性。农业旱灾风险综合评估的结果表明,泾河流域农业旱灾风险的高风险区位于该地区北部,低风险区位于该地区南部,且不同等级风险区呈现出自东向西、自南向北逐渐降低的总体趋势,但不同等级风险区呈现间隔分布的趋势。 相似文献
994.
《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
995.
996.
Pang Guizhen 《地球科学与环境学报》1997,(1)
从地学的角度研究关中地区旅游景观不难发现:关中地区山水景观具有深刻的地学成因内涵;古遗址景观具有深刻的环境地学内涵;古建筑的选址和布局充分表现出古代中国人民对地学环境的深刻理解和适度的把握与利用;古遗址与古建筑的表层“风水模式”具有深刻的地学内涵,而赋予一定的科学意义. 相似文献
997.
《The Professional geographer》1987,39(2):238-266
Book Reviewed in this article: Women, Work, and Ideology in the Third World . Haleh Afshar, ed. The Birth of the National Park Service. The Founding Years 1913–33 . Horace M. Albright Theatres of Accumulation: Studies in Asian and Latin American Urbanization . Warwick Armstrong and T.G. McGee. New Tools for Social Scientists, Advances and Applications in Research Methods . William D. Berry and Michael S. Lewis -Beck , eds . Uncertain Dimensions: Western Overseas Empires in the Twentieth Century . Raymond F. Betts. Geography of Sugar Cane . Helmut Blume. The Mines of Neptune: Minerals and Metals from the Sea . Elisabeth Mann Borgese. Geographical Dimensions of Energy . F.J. Calzonetti and B.D. Solomon, eds. Statistical Methods for Geographers . W. A. V. Clark and P. L. Hosking. In The Wake of Columbus, Islands and Controversy . John DeVorsey, Jr., and John Parker, eds. Housing, States and Localities . Peter Dickens, Simon Duncan, Mark Goodwin and Fred Gray. Physician Location and Specialty Choice . Richard L. Ernst and Donald E. Yett. Practical Ecology for Geography and Biology: Survey, Mapping, and Data Analysis . D.D. Gilbertson , M. Kent and F.B. Pyatt Large Scale Water Transfers: Emerging Environmental and Social Experiences . Genady N. Golubev and Asit K. Biswas, eds. The Nature of the Environment . Andrew Goudie. Planning for Population Change . W.T.S. Gould and R. Lawton. The Niger and its Neighbors: Environmental History and Hydrobiology. Human Use and Health Hazards of the Major West African Rivers . A.T. Grove, ed. Remote Sensing of Ice and Snow . Dorothy K. Hall and Jaroslav Martinec. Atlas of Antebellum Southern Agriculture . Sam Bowers Hilliard. Galilee Divided; The Israel-Lebanon Frontier, 1916-1984 . Frederic C. Hor . Plains Country Towns . John C. Hudson. Agricultural Geography: A Social and Economic Analysis . Brian W. Ilbery. Industry in the 1980s: Structural Change and Interdependence . U.N. Industrial Development Organization. Crabgrass Frontier: The Suburbanization of the United States . Kenneth T. Jackson. The Industrial Geography of Italy . Russell King. Studies in Linguistic Geography: The Dialects of English in Britain and Ireland . John M. Kirk, Stewart Sanderson, J.D.A. Widdowson, eds. Tourism: A Community Approach . Peter E. Murphy. Cities and Services: The Geography of Collective Consumption . Steven Pinch. An Historical Geography of Europe 1800–1914 . Norman J. G. Pounds. An Introduction to Human Ecology Research on Agricultural Systems in Southeast Asia . A. Terry Rambo and Percy E. Sajise, eds. Discovering Past Landscapes . Michael Reed, ed. Managing the Ocean: Resources, Research, Law . Jacques G. Richardson, ed. Carta fitosociologica de la transecta botanica de la Patagonia Austral . F.A. Roig , Juan Anchorema , Orlando Dollenz , A.M. Faggi and Eduardo Mandez Intermetropolitan Migration in Canada: Changing Determinants over Three Decades . R. Paul Shaw. Chinese Cities—The Growth of the Metropolis since 1949 . Victor F. Sit, ed. Urbanization in the World-Economy . Michael Timberlake, ed. The Al Business: Commercial Uses of Artificial Intelligence . Patrick H. Winston and Karen A. Prendergast, eds. 相似文献
998.
JOHN A. CROSS 《Geographical review》2006,96(1):1-23
ABSTRACT. As the number of American dairy farms rapidly declines, the character and spatial distribution of the remaining farms is undergoing fundamental change. Concentrating on an examination of both the smallest commercial farms (with 10–49 cows) and the largest dairy operations (with at least 500 cows), this study shows that megadairies are spreading from California into Idaho and America's traditional dairy belt, while Amish farmers are growing in prominence among those milking fewer than fifty cows. Although the greatest proportional declines in dairy farms have been among the smaller operations, average farm size throughout much of the nation remains well below 100 cows. Within a decade Amish farmers may operate one‐fifth of the nation's dairy farms as they expand across the traditional dairy belt, and 500‐cow dairies in the Midwest will outnumber those in California. 相似文献
999.
《The Professional geographer》1987,39(3):363-386
Book Reviewed in this article: Hillslope Processes. Binghamton Symposia in Geomorphology International Series: 16. Athol D. Abrahams , ed. The Atlas of Central America and the Caribbean. The Diagram Group . The Cultural Atlas of Islam. Isma'il R. al Faruqi and Lois Lamaya'al Faruqi . Atlas of Israel Contemporary Africa: Development, Culture and the State. Morag Bell . Fundamentals of Physical Geography. David Briggs and Peter Smithson . The Bicentennial Census: New Directions for Methodology in 1990. Constance F. Citro and Michael L. Cohen , eds . World Patterns of Modern Urban Change: Essays in Honor of Chauncy D. Harris. Michael P. Conzen , ed . New Directions for Agriculture and Agricultural Research: Neglected Dimensions and Emerging Alternatives. Kenneth A. Dahlberg , ed . Water Resources Atlas of Florida. E.A. Fernald and D.J. Patton , eds . Landscape Ecology. R.T.T. Forman and M. Godron . The Myth of the North American City: Continentalism Challenged. Michael Goldberg and John Mercer . The Permafrost Environment. Stuart A. Harris . Climate and Circulation of the Tropics. Stefan Hastenrath . The Island of South Georgia. Robert Headland . The Making of Urban Europe, 1000-1950. Paul M. Hohenberg and Lynn Hollen Lees . Bombay in Transition: The Growth and Social Ecology of a Colonial City, 1889–1980. Meera Kosambi . Plant Closings; Public or Private Choices? Richard B. McKenzie , ed . Malaysia: Tradition, Modernity and Islam. R.S. Milne and Diane K. Mauzy . Technology on the Frontier: Mining in Old Ontario. Dianne Newell . The Maritime Political Boundaries of the World. J.R.V. Prescott . Tall Office Buildings in the United States. James W. Pygman and Richard Kateley (Real Estate Research Corporation). Technology, Regions, and Policy. John Rees , ed . The United States and the Regional Organization of Asia and the Pacific: 1965-1985. W.W. Rostow . Renewable Energy: Progress, Prospects. Stephen W. Sawyer Wisconsin Foundations. Gwen Schultz . Dwelling, Place and Environment: Towards a Phenomenology of Person and World. David Seamon and Robert Mugerauer , eds . Power and Place: Canadian Urban Development in the North American Context. Gilbert A. Stelter and Alan F.J. Artibise , eds . Small Firms in Regional Economic Development: Britain, Ireland and the United States. D. J. Storey , ed . Mathematical Methods in Human Geography and Planning. A. G. Wilson and R. J. Bennett . El Niño North: Niño Effects on the Eastern Subarctic Pacific Ocean. W. S. Wooster and D. L. Fluharty , eds . The Soviet Iron and Steel Industry. Craig ZumBrunnen and Jeffrey Osleeb . 相似文献
1000.