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当前在干旱区土壤水分研究工作中,开展利用微波遥感技术高精度估算稀疏植被覆盖条件下地表粗糙度参数的研究是一项非常有意义的工作。基于微波遥感数据,结合土壤水分实测资料,以IEM模型为基础,分析雷达后向散射系数与土壤含水量、地表粗糙度参数之间的关系,利用最小二乘法和非线性回归的方法,建立光滑地表条件下的土壤含水量模型。结果表明:模型提取的土壤水分与实测值之间有很好的相关性,决定系数达到0.886,所建立的土壤水分信息提取模型在裸土以及稀疏植被覆盖地区能够得到较好的应用效果。 相似文献
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基于支持向量机回归算法的土壤水分光学与微波遥感协同反演 总被引：1，自引：0，他引：1
《地理与地理信息科学》2017,(6)
利用遥感技术反演土壤水分对于我国西北地区农业干旱问题研究具有重要意义。该文以新疆焉耆盆地为研究区域,分别利用微波遥感数据(Sentinel-1ASAR)和光学遥感数据(Landsat8)计算土壤后向散射系数(σ0soil)和改进型温度植被干旱指数(MTVDI),并将σ0soil和MTVDI参数作用于支持向量机(SVM)回归算法,探讨了不同参数条件下SVM模型在土壤水分反演中的适应性。实验结果表明,相比只用单因子(σ0soil或MTVDI)作为模型参数,以σ0soil和MTVDI两者共同作为SVM模型输入参数时,土壤水分监测精度显著提高,其建模集决定系数R2=0.81,均方根误差RMSE=3.16%;验证集R2=0.89,RMSE=3.15%。最后,利用最优模型对研究区土壤水分进行了反演,并对不同土地类型含水量进行了评价,可为光学遥感与微波遥感协同反演土壤水分提供参考。 相似文献
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TVDI用于干旱区农业旱情监测的适宜性 总被引：8，自引：0，他引：8
基于地表温度/植被指数(Ts/VI)特征空间建立的温度植被干旱指数(TVDI)受诸多因素的影响,其中一个重要的影响因素是植被指数,该指数在高、低植被覆盖时的敏感性不同,从而导致TVDI对旱情监测的准确度不同.针对这一问题,以新疆塔里木盆地北缘渭干河-库车河三角洲绿洲为研究区,选择2011年4月、8月两景TM影像,利用归一化植被指数(NDVI)和比值植被指数(RVI)分别建立Ts/VI特征空间,线性拟合特征空间的上、下边界,计算得到两种温度植被干旱指数(TVDI-NDVI、TVDI-RVI).用TVDI与同期野外实测的土壤含水量数据进行回归分析.结果表明:(1)植被指数、地表温度、土壤水分之间有显著互动关系,以不同植被指数计算得到的两种TVDI与表层土壤水分相关性较好,均能够反映区域土壤干旱状况;(2)由于植被指数对植被探测的敏感性,在4月低植被覆盖时,TVDI-NDVI与表层土壤水分的相关性较高,为0.4299,8月高植被覆盖时,TVDI-RVI与表层土壤水分的相关性较高,达到0.5791;(3)在低植被覆盖区域,NDVI较RVI敏感,而在高植被覆盖区域,RVI敏感性较高.RVI适用于高植被覆盖时反演土壤湿度,NDVI则更适用于中、低植被覆盖时. 相似文献
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城市地域地表温度-植被覆盖定量关系分析——以深圳市为例 总被引：33，自引：6，他引：33
地表温度-植被覆盖间的关系一直是城市热岛研究的热点之一,两者均为描述生态系统特征的重要参数。本文利用深圳市2004年的ETM+影像,基于遥感技术提取相关的下垫面类型、地表温度和植被覆盖等信息,探讨不同下垫面类型对地表温度-植被覆盖关系的影响,并结合分形维度计算方法,比较不同分辨率下地表温度、植被覆盖及其相关关系的变化。研究结果表明,植被覆盖程度与地表温度之间存在明显的负相关,并且在不同的植被覆盖程度下,地表温度-植被覆盖关系呈现分段线性关系。下垫面类型及其组合主要通过植被覆盖的分布对地表温度产生影响。而在不同空间分辨率下(30m至960m),地表温度和植被覆盖的空间变异程度均表现为先升后降,在120m的分辨率下,两者的相关程度达到最高。结果证实区域植被覆盖状况可直接影响辐射、热动力以及土壤水分等多种地表特征,从而导致地表温度分异等。 相似文献
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基于地表温度-植被指数特征空间的区域土壤水分反演 总被引：6，自引：1，他引：5
针对目前西北地区广泛存在的农业干旱问题,选取了新疆塔里木盆地北缘渭干河-库车河三角洲绿洲为研究区,选择云量较少的两幅TM影像,建立地表温度-植被指数特征空间。首先利用线性方程拟合了特征空间的上下边界,比较利用归一化植被指数(NDVI)建立的地表温度-植被指数特征空间Ts/NDVI和利用改进型土壤调整植被指数(MSAVI)构建的地表温度-植被指数特征空间Ts/MSAVI形状的差异,并计算得到两种温度植被干旱指数(Temperature vegetation dryness index-TVDI,分别为TVDIN和MTVDI)。对TVDI与同期野外不同深度的实测土壤重量含水量数据进行回归分析,建立TVDI估测土壤水分的经验模型并对模型进行验证。研究结果表明,TVDIN和MTVDI均能够反演表层土壤水分,其中MTVDI与土壤水分相关性比TVDIN与土壤水分相关性要高,MTVDI能够更好地反映区域土壤水分状况,是一种更有效的土壤水分监测方法,对农业干旱监测具有一定的科学依据。 相似文献
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沙坡头地区固沙植被土壤水分动态研究 总被引：81，自引：26，他引：55
沙坡头地区始建于1956年的无灌溉人工固沙植被,是我国交通干线防沙体系的成功模式。利用40余年的土壤水分定位观测数据,分析了不同期间建立的固沙植被土壤水分的时空变化特征及对植被的影响。结果表明,固沙植被发展至9~10a后土壤含水量开始明显下降,特别是较深层(>100cm)的含水量下降明显;0~40cm层土壤水分含量与降水相关显著,而降水对40~300cm层土壤水分的含量影响不显著;深根系固沙植物对根际区域水分的利用,进一步恶化了固沙区土壤深层的水分状况,进而抑制了这些植物的生长和生存,间接地影响了原有固沙植被组成和稳定性;经过40多年的演变,固沙植被中优势灌木种的盖度从最大盖度47.6%降至6%~9%,群落中草本和微生物结皮层得到发育。当深根系灌木的盖度降低至6%~9%时,深层土壤可维持一个相对稳定的低含水量。 相似文献
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额济纳绿洲不同植被覆盖下土壤特性的时空变化 总被引：3，自引：1，他引：2
额济纳绿洲地处干旱内陆河地区。在分析额济纳绿洲土壤特性的基础上,以不同植被类型下的土壤作为分析对象,根据观测的土壤含水量数据及环境因子的观测数据,研究了额济纳绿洲土壤水分的时空变化规律,分析了土壤水分变化与环境因子之间的关系,建立了土壤含水量与环境因子之间的回归模型。研究结果表明,土壤剖面土壤类型及结构差异较大,土壤类型的差异主要受成土条件的制约和外部自然环境的影响,戈壁地区与其他几种植被类型下的土壤差异最为显著;土壤类型及结构的差异,土壤容重变化的特性及土壤水势、土壤含水量的变化,直接影响着植被的生长和分布;额济纳绿洲不同植被类型下的土壤含水量变化差异显著;土壤含水量的季节变化分析表明,土壤剖面中不同层的土壤含水量变化也存在着一定的差异,可以分成不同的稳定变化层,急剧变化层和相对稳定层;土壤含水量的日变化受环境因子的影响较为明显,空气温湿度、土壤温度及地下水水位埋深是影响土壤含水量最为显著的因素。 相似文献
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摘要：土壤水分是全球水循环的重要组成成分,对研究土壤水分的空间分布、农作物长势和产量 、气候变化、水资源时空分布等有着重要意义 。本文利用Sentinel（哨兵）系列主动微波雷达卫星SAR（Sentinel-1）结合光学卫星（Sentinel-2）对格尔木中下游低矮植被覆盖下的地表土壤水分进行反演研究, 探讨不同极化组合方式和水云模型前后的土壤水分含量反演方法的适用性。结果表明：其中VV (VV Polarization) 极化对比VH (VH Polarization) 极化更加适用该区域,VV极化结合归一化水指数 (NDWI）反演地表土壤水分精度达到42.6%,拟合精度最高,VH极化仅为22.6%;利用水云模型去除植被覆盖后对地表土壤水分的反演精度有所提升,其中,VV极化精度提高约3.5%,VH极化提高1.5%;Sentinel系列卫星影像对于干旱区的土壤水分的反演具有较好的适用性。本文旨在探索一种适用于该研究区乃至柴达木盆地土壤水分实现大面积实时监测的可靠依据和手段。 相似文献
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《The Professional geographer》1984,36(1):106-142
Book Reviewed in this article: Development and Environment in Peninsular Malaysia . S. Robert Aiken, Colin H. Leigh, Thomas R. Leinbach, Michael R. Moss. The Rural-Urban Fringe: Canadian Perspectives . Ken B. Beesley and Lorne H. Russwurm, eds. Women and Development . Lourdes Benería, ed. The Border that Joins: Mexican Migrants and U.S. Responsibility . Peter G. Brown and Henry Shue, eds. Cities of the World: World Regional Urban Development . Stanley D. Brunn and Jack L. Williams, eds. Time Resources, Society, and Ecology: On the Capacity for Human Interaction in Space and Time (Vol. I, Preindustrial Societies). Tommy Carlstein. Urban Geography . David Clark. Spanish City Planning in North America . Dora P. Crouch, Daniel J. Garr, and Axel I. Mundigo. Not On Our Street: Community Attitudes to Mental Health Care . M. J. Dear and S. M. Taylor Unequal growth: Urban and Regional Employment Change in the U.K. Stephen Fothergill and Graham Gudgin. Agricultural Land in an Urban Society . Owen J. Furuseth and John T. Pierce. The Petroleum Industry in Oil-Importing Developing Countries . Fariborz Ghadar. Historical Understanding in Geography, An Idealist Approach . Leonard Guelke. Regional Planning in Europe . R. Hudson and J. R. Lewis, eds. Remote Sensing for Resource Management . Chris J. Johannsen and James L. Sanders, eds. Geography and The State . R. J. Johnston. Texas Graveyards: a Cultural Legacy . Tlrry G. Jordan. The Politics of Location: An Introduction . Andrew Kirby. A Social Geography of the City . David Ley. Energy and the Future . Douglas MacLean and Peter Brown, eds. The Natural Environment of Newfoundland Past and Present . A. G. Macpherson and J. B. Macpherson, eds. Tourism: Economic, Physical and Social Impacts . Alister Mathieson and Geoffrey Wall. Railroads and Land Grant Policy: A Study in Government Intervention . Lloyd J. Mercer. Progress in Rural Geography . Michael Pacione, ed. Progress in Urban Geography . Michael Pacione, ed. Models of Spatial Inequality: Settlement Patterns in Historical Archaeology . Robert Paynter. Natural Hazard Risk Assessment and Public Policy, Anticipating the Unexpected . William J. Petak and Arthur A. Atkisson. The Nature of Geomorphology . Alistair F. Pitty. Regional Conflict and National Policy . Kent A. Price Women and Spatial Change: Learning Resources for Social Science Courses . Arlene C. Rengert and Janice J. Monk, eds. Urban and Regional Analysis for Development Planning . Richard Rhoda. Rivers: Form and Process in Alluvial Channels . Keith Richards. This Remarkable Continent: An Atlas of United States and Canadian Society and Culture . John F. Rooney, Jr., Wilbur Zelinsky, and Dean R. Louder, gen. eds. The Origins of Open-Field Agriculture . Trevor Rowley, ed. Residential Location Determinants of the Older Population . Gundars Rudzitis. Borderland Sourcebook: A Guide to the Literature on Northern Mexico and the American Southwest . Ellwyn R. Stoddard, Richard L. Nostrand, and Jonathan P. West, eds. Arctic and Antarctic . David Sugden. Tall Timbers Ecology and Management Conference, February 22–24, 1979, Proceedings No. 16 . Graphic Communication and Design in Contemporary Cartography (Progress in Contemporary Cartography , Vol. II). D. R. Fraser Taylor, ed. Living with Energy Shortfall: A Future for American Towns and Cities . Jon Van Til. The United States: Habitation of Hope . J. Wreford Watson. Air Photo Interpretation for Archaeologists . D. R. Wilson. Urban and Rural Change in West Germany . Trevor Wild, ed. Population and Resources . Harry Robinson. 相似文献
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《The Professional geographer》1984,36(2):250-283
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
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<正>1 Introduction In 2013,Chagusaba,which is traditional tea-grass integrated system in Shizuoka,were accepted as new world heritage site of agriculture.Shizuoka prefecture occupies a variety of elevations,from 0 to 3000m or more above sea level.Because of the diversity of land features and climates,this area produces 167 agricultural commodities.In addition,a lot of traditional agriculture and over200 local native varieties of crops have been conserved in Shizuoka 相似文献
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MIN Qingwen 《资源与生态学报(英文版)》2014,5(4):289-290
<正>There are more than 10000 years of agricultural development history in the world that has provided very fruitful and ingenious traditional knowledge and experiences reflecting the evolution of humanity and the nature.In2002,the Food and Agriculture Organization of the United Nations(FAO)initiated an international partnership initiative of"Conservation and Adaptive Management of Globally Important Agricultural Heritage Systems 相似文献
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《The Professional geographer》2013,65(1):85-89
Reviews of geographic software in this article: DEMO-GRAPHICS: WORLD POPULATIONS AND PROJECTIONS. ESP GAUSS. CEMODEL S. Damus LIMDEP. William H. Greene MICROSTAT 4.1 OTIS PCIPS. (Personal Computer Image Processing System). H.J. Meyers and R. Bernstein. REGRESSION ANALYSIS OF TIME SERIES (RATS) SPSS/PC+ URBAN DATA MANAGEMENT SOFTWARE (UDMS) 相似文献
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《The Professional geographer》1985,37(2):226-262
Book Reviewed in this article: The City in Cultural Context . John Agnew, John Mercer, David Sopher, eds. Soils and Geomorphology Peter W. Birkeland. Urbanization and Settlement Systems, International Perspectives . L. S. Bourne, R. Sinclair, and K. Dziewoński. eds. An Introduction to Urban Historical Geography . Harold Carter. Overshoot, The Ecological Basis of Revolutionary Change . William J. Catton, Jr. Rivers of the World . Eberhard Czaya. Jewish Communities in Frontier Societies: Argentina, Australia and South Africa . Daniel J. Elazar with Peter Medding. Color in Public Spaces: Toward a Communication-Based Theory of the Urban Built Environment. Kenneth E. Foote. Spatial Statistics and Models. Gary L. Gaile and Cort J. Willmott, eds. Mega-Geomorphology. Rita Gardner and Helen Scoging, eds. Technological Change and Regional Development. Gillespie, ed. The Arid Lands: Their Use and Abuse. R. L. Heathcote. The Location of Industry in Britain. A. G. Hoare. Groundwater as a Geomorphic Agent . R. G. LaFleur, ed. Rural Public Services: International Comparisons. Richard E. Lonsdale and Gyorgy Enyedi, eds. Saving Water in a Desert City. William E. Martin, Helen M. Ingram, Nancy K. Laney, and Adrian H. Griffin. Water Resources: Distribution, Use and Management. John R. Mather. Transnationals and the Third World: The Struggle for Culture. Armand Mattelart. South Hadley, MA: USGS Digital Cartographic Data Standards. R. B. McEwen, R. E. Witmer, and B. S. Ramey, eds. The Ecosystem Concept in Anthropology. Emilio F. Moran, ed. Boulder, CO: Women, Men, and the International Division of Labor. June Nash and Maria Patricia Fernandez-Kelly, eds. Nuclear Power: Assessing and Managing Hazardous Technology. Martin J. Pasqualetti and K. David Pijawka, eds. Mary Somerville and the Cultivation of Science 1815-1840. Elizabeth Chalmers Patterson. An Introduction to Coastal Geomorphology. John Pethick. Late Quaternary Environments of the United States , Vol. 1, The Late Pleistocene. Stephen C. Porter, ed. Planning and Ecology. R. D. Roberts and T. M. Roberts, eds. Regionalism and the Pacific Northwest. William G. Robbins, Robert J. Frank, and Richard E. Ross, eds. Environment and Health. Anthony J. Rowland and Paul Cooper. Sunbelt/Snowbelt: Urban Development and Regional Restructuring. Larry Sawers and William K. Tabb, eds. The Bad Earth. Environmental Degradation in China. Vaclav Smil. Armonk, NY: Voyage into Substance: Art, Science, Nature, and the Illustrated Travel Account, 1760–1840. Barbara Maria Stafford. The Institute of British Geographers: The First Fifty Years. Robert W. Steel. Visions of the Past. Christopher Taylor and Richard Muir. Glacial Lake Agassiz. J. T. Teller and Lee Clayton, eds. The Tule Breakers: The Story of the California Dredge. John Thompson and Edward A. Dutra. The Balkan City 1400–1900. Nikolai Todorov. Explanation, Prediction and Planning: the Lowry model. Michael J. Webber. Mercedes Reales: Hispanic Land Grants of the Upper Rio Grande Region. Victor Westphall. The World Atlas of Revolutions. Andrew J. M. Wheatcroft. The West European City, A Social Geography. Paul White. Urban Elites and Mass Transportation. J. Allen Whitt. Princeton, NJ: Urban Life In Contemporary China. Martin King Whyte and William L. Parish. The Demand for Energy in the Soviet Union. David Wilson. London and Canberra: Rethinking Geographical Inquiry. J. David Wood, ed. 相似文献
18.
《The Professional geographer》1983,35(2):230-260
Book Reviewed in this article: Rabat: Urban Apartheid in Morocco . Janet Abu -Lughod . Marketplaces in a Developing Country: The Case of Western Nigeria . Isaac Ayinde Adalemo . Farming Development and Space: A World Agricultural Geography . Bernd Andreae . Section and Party: A Political Geography of American Presidential Elections, from Andrew Jackson to Ronald Reagan . J. Clark Archer and Peter J. Taylor . Women and Space: Ground Rules and Social Maps . Shirley Ardener , ed. European Progress in Spatial Analysis . R. J. Bennett , ed. The Origins of Academic Geography in the United States . Brian W. Blouet Geographic Perspectives on Global Problems . Ronald Reed Boyce . Seasonal Dimensions to Rural Poverty . Robert Chambers , Richard Longhurst and Arnold Pacey eds. The New Nationalism and the Use of Common Spaces: Issues in Marine Pollution and the Exploitation of Antarctica . Jonathan I. Charney , ed. Communications Tomorrow: The Coming of the Information Society . Edward Cornish , ed. The Design of Suburbia . Arthur Edwards . Explorer on the Northern Plains: Lieutenant Gouverneur K. Warren's Preliminary Report of Explorations in Nebraska and Dakota in the Years 1855–56–57. With an Introduction by Frank N. Schubert . The Changing Climate: Responses of the Natural Flora and Fauna . Michael J. Ford . Essentials of Physical Geography . Robert E. Gabler , Robert J. Sager , Sheila Brazier , and Daniel L. Wise. The Road to Jaramillo . William Glen . Valued Environments . John R. Gold and Jacquelin Burgess , eds. Proximity and Preference: Problems in the Multidimensional Analysis of Large Data Sets . Reginald G. Golledge and John N. Rayner , eds. A Search for Common Ground . Peter Gould and Gunnar Olsson , eds. Geography: Its History and Concepts . Arild Holt -Jensen . A Population Geography . Huw R. Jones . The Human Mosaic: A Thematic Introduction to Cultural Geography, 3rd ed. Terry G. Jordan and Lester Rowntree . Urban Social Geography: An Introduction . Paul Knox . The Anatomy of Job Loss: The How, Why and Where of Employment Decline . Doreen Massey and Richard Meegan . The Information Society as Post-Industial Society . Yoneji Masuda . Map Librarianship, 2nd ed. Harold Nichols . India: Cultural Patterns and Processes . Allen G. Noble and Ashok K. Dutt , eds. The God that Limps: Science and Technology in the Eighties . Colin Norman . Geography: An Introductory Perspective . Robert E. Norris , Keith D. Harries and John D. Vitek . The Politics of Technology Assessment . David M. O'Brien and Donald A. Marchand . Ethnic Segregation in Cities . Ceri Peach , Vaughan Robinson and Susan Smith , eds. Churches and Church Membership in the United States, 1980 . Bernard Quinn , Herman Anderson , Martin Bradley , Paul Goetting and Peggy Shriver . Energy in Australia: Politics and Economics . Hugh Saddler . Development from Above or Below? The Dialectics of Regional Planning in Developing Countries . Walter B. Stóuhr and D. R. Fraser Taylor , eds. Human Impact on the Ecosystem . Joy Tivy and Greg O'Hare . Plants and People: Vegetation Change in North America . Thomas R. Vale . The Mapmakers: The Story of the Great Pioneers in Cartography from Antiquity to the Space Age . John Noble Wilford . 相似文献
19.
Raanan Katzir 《寒旱区科学》2013,5(6):0767-0768
Desertification is a global phenomenon that affects about two billion people. It occurs in arid zones where the annual precipitation is below 400 mm, partic- ularly in the marginal areas of the world＇s largest deserts. It is a result of water and wind erosion, over- grazing, global warm-ing, improper soil cultivation, and increased pressure ot population growth, and it causes degradation of soil and natural and agricultural vegetation. The direct result is less food for people and livestock, which influences pop- ulation and animal husbandry fluctuations. Despite ef- forts to combat and reduce desertification, the affected areas are annually increasing. 相似文献
20.
《The Professional geographer》1987,39(1):94-129
Book Reviewed in this article: The Rice Economy of Asia . Randolph Barker and Robert W. Herdt with Beth Rose. Using Microcomputers: A Guidebook for Writers, Teachers, and Researchers in the Social Sciences . Blaine A. Erie—the Lake that Survived . Noel M. Burns. Geology and Society . Donald R. Coates. Caves and Karst of Kentucky . Percy H. Dougherty, ed. Altered Harvest: Agriculture, Genetics, and the Fate of the World's Food Supply . Jack Doyle. The Middle East and North Africa, A Political Geography . Alasdair Drysdale and Gerald H. Blake. Clamor at the Gates. The New American Immigration . Nathan Glazer, ed. Development and the Landowner: An analysis of the British experience . Robin Goodchild and Richard Munton. Discovering Landscape in England and Wales . Andrew Goudie and Rita Gardner. The Modern Plantation in the Third World . Edgar Graham and Ingrid Floering. Social Relations and Spatial Structures . Derek Gregory and John Urry, eds. The World Food Problem 1950–1980 . David Grigg. Costa Rica: A Geographical Interpretation in Historical Perspective . Carolyn Hall. The Urbanization of Capital: Studies in the History and Theory of Capitalist Urbanization . David Harvey Consciousness and the Urban Experience: Studies in the History and Theory of Capitalist Urbanization . David Harvey. Reviving Main Street . Deryck Holdsworth, ed. Rural Roads and Poverty Alleviation . John Howe and Peter Richards, eds. Uneven Development in Southern Europe: Studies of Accumulation, Class, Migration and the State . Ray Hudson and Jim Lewis, eds. Karst Geomorphology . J. N. Jennings. The Geomorphology of North-west England . R. H. Johnson, ed. Climate Impact Assessment: Studies of the Interaction of Climate and Society . Robert Kates, Jesse Ausubel, Mimi Berberian, eds. Public Service Provision and Urban Development . Andrew Kirby, Paul Knox, and Steven Pinch, ed. State and Market: The Politics of the Public and the Private . Jan-Erik Lane, ed. Living Cities . Twentieth Century Fund Task Force on Urban Preservation Policies. World Climatic Systems . John G. Lockwood. Urban Ethnicity in the United States. New Immigrants and Old Minorities . Lionel Maldonaldo and Joan Moore, eds. Culture and Conservation: The Human Dimension in Environmental Planning . Jeffrey A. McNeely and David Pitt, eds. The Andean Past. Land, Societies, and Conflicts . Magnus Mörner. Gaia: An Atlas of Planet Management . Norman Myers, ed. Progress in Industrial Geography . Michael Pacione, ed. Progress in Political Geography . Michael Pacione, ed. Rivers and Landscape . Geoff Petts and Ian Foster. Urbanization and Planning in the 3rd World: Spatial Perceptions and Public Participation . Robert B. Potter. One Island, Two Nations? A Political Geographical Analysis of the National Conflict in Ireland . D. G. Pringle. Circulation in Third World Countries . R. Mansell Prothero and Murray Chapman. The Ozarks Outdoors: A Guide for Fishermen, Hunters, and Tourists . Milton D. Rafferty. Suburban Burglary: A Time and a Place for Everything . George Rengert and John Wasilchick. Geomorphology and Soils . K.S. Richards, R.R. Arnett, and S. Ellis, eds. The Homes and Homeless of Post-War Britain . Frederick Shaw. Indochinese Refugees in America . Paul J. Strand and Woodrow Jones, Jr. Wild Horses and Sacred Cows . Richard Symanski. Forever Wild: Environmental Aesthetics and the Adirondack Forest Preserve . Philip G. Terrie. The Regional Economic Impact of Technological Change . A.T. Thwaites and R.P. Oakey, eds. The Good Life . Yi-Fu Tuan. 相似文献