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自１９８８年１１月至１９８９年３月，对南极长城湾（６２°１３′Ｓ，５８°５７′Ｗ）中５个站位的水温、ｐＨ值、海水透明度、水下照度、水中和海冰中叶绿素含量、磷酸盐含量、亚硝酸盐和硝酸盐含量等理化要素，每月进行１至２次不定期的常规测定。在整个调查期间，海水温度变化范围在－１．６～２．２°Ｃ之间，ｐＨ值变化范围在８．０～９．１之间，海水中叶绿素ａ的变化范围在０．３０～１．４８ｍｇ／ｍ３之间，叶绿素ａ的最大值出现在１１月２６日５号站的表层水中，海冰中叶绿素ａ的含量远远高于海水中的含量，海冰中叶绿素ａ的变化范围在２．５５～５６．８４ｍｇ／ｍ３之间。磷酸盐含量变化范围在１．０２３～２．１８７μｇＰ／Ｌ，亚硝酸盐含量变化范围在０．０９３～０．１８６μｇＮ／Ｌ之间，硝酸盐含量变化范围在１３．３０８～２６．５８４μｇＮ／Ｌ之间。本文对以上结果作了初步探讨 相似文献
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自１９９２年４月１２日至１２月３０日对中山站附近内拉峡湾冰下水柱中浮游植物生物量以及环境因子的季节变化进行了测定。水中叶绿素ａ含量在０．０３－２１．４０ｍｇ／ｍ３之间波动，在覆冰期间，生物量基本上随深度的增加而下降；５－９月份各层次的生物量普遍低于０．５ｍｇ／ｍ３，８－９月份低于０．１ｍｇ／ｍ３。各层次中以水表含量的季节变化最为明显，成冰后在９月份形成低谷，于１２月中旬紧接着冰底水华的消失而形成单一峰值。生物量中微型浮游植物（＜２０μｍ）的比重在４－９月份的多数层次占有一半以上，１０月份后随着生物量的上升而下降，在水华期水表的比重最低，仅占总量的３．２％。其柱总生物量基本上与冰中生物量处于同一数量级，在冰藻水华期其量值甚至低于冰中生物量。营养盐（μｍｏｌ／Ｌ）的波动范围为ＰＯ４－Ｐ：０．３２－０．７９，ＳｉＯ３－Ｓｉ：２６．４７－６９．９２，ＮＯ３－Ｎ：１．４１－３１．７５，尽管水华期水表营养盐含量降至观测期间的最低点，但仍能满足冰下浮游植物的生长所需。光辐照度由于在冰水界面的量值仅为冰表入射光的不足５．３％至低于１％，成为水中产量最为可能的限制因子。 相似文献
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本文介绍南极拉斯曼丘陵湖泊水化学特征。对１３个湖泊的调查和统计分析表明，湖水以Ｎａ＋和Ｃｌ－为主要优势离子，不含有ＣＯ３２－离子，营养物质（Ｎ、Ｐ、ＳｉＯ２）在湖水中普遍偏低，而且湖水和雪样无机氮组分均以ＮＨ４＋为主，水化学类型比较单一，都属氯化物Ｎａ＋型贫营养水体。Ｎａ＋、Ｃｌ－、ＳＯ４２－的高浓度，特别是Ｂｉｇ湖、莫愁湖和Ｈｅａｒｔ湖水中离子含量明显的高，指示拉斯曼丘陵地区的降水来源以海洋气团为主，并受海洋环境影响强烈。微量元素分布在０．０１～２．０μｇ／ｌ之间，接近于水圈这些元素的浓度值。 相似文献
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黄淮海平面原沙地不同治理利用措施下土壤性质的差异 总被引：2，自引：0，他引：2
延津站经过７－８ａ改造后,试区的０农业用地,果园地用,封育沙垄地较试区未封育裸露沙垄地,粉粒含量增加９－１６．６４倍,物理性粘粒含量增加１．１７－３．６７倍,土壤有机质含量增加８．４－１２．６倍,全Ｎ含量增加３．６－５．２５倍,全Ｐ含量增加１．５２－２．１９倍。 相似文献
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塔克拉玛干沙漠膜地地下水质的应用评价 总被引：1，自引：0，他引：1
长期利用高矿化度地下水灌溉造成沙质土壤的次生盐渍化是塔克拉玛干沙膜腹地建立人工生态系统的主导限制因素之一。据１９９２年与１９９４年塔克拉玛干沙膜地满参与中三点２年的试验研究结果认为：在灌溉水的适宜应用条件下，利用矿化度为４ｇ／Ｌ－５ｇ／Ｌ的地下水灌溉种植瓜果蔬菜和固沙植物是能够成功的；生长季风土壤含盐量＜０．１％。 相似文献
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研究了不同浓度ＭｇＣｌ２（１．９９８、３．８６７、５．７３５％）溶液，在不同温度（２５、５５℃）下，对软钾镁矾在Ｋ＋，Ｍｇ２＋／ＳＯ_４￣２－，Ｃｌ－Ｈ２Ｏ四元体系中溶解转化过程的影响，采用龙格－库塔微分数值法拟合其溶解过程和结晶过程动力学方程。结果表明在一定浓度ＭｇＣｌ２溶液中软钾镁矾是不相称溶解，Ｋ２ＳＯ４先于ＭｇＳＯ４溶解进入溶液中，ＭｇＣｌ２溶液浓度越大，温度越高，溶解速度越快，Ｋ２ＳＯ４结晶速度也越快．溶解受扩散和表面反应控制，Ｋ２ＳＯ４结晶受扩散控制． 相似文献
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提高食物链硒通量防治大骨节病和克山病示范研究 总被引：23，自引：1，他引：22
本研究在黄土高原的陕西省彬县大骨节病和克山病重病区,进行小麦、蔬菜的叶面喷Ｓｅ和主食加Ｓｅ防治地方病的示范研究。结果显示,喷Ｓｅ小麦含Ｓｅ量达０．０８１μｇ／ｇ,明显高于未喷Ｓｅ的小麦（０．００９μｇ／ｇ）;示范点膳食含Ｓｅ达０．０７６μｇ／ｇ,显著高于对照点（０．０１４μｇ／ｇ）;示范点人均日摄Ｓｅ量由１３．４０μｇ／ｇ提高到６０．３９μｇ／ｇ;大骨节病Ｘ线阳性检出率由４３．３３％下降到６．４５％,达到国家控制标准。 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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《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》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
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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
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《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
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《The Professional geographer》1987,39(1):85-94
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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