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861.
《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
862.
试论我国煤炭城市产业结构的调整 总被引:9,自引:1,他引:9
在对淮南、淮北两个典型煤炭城市进行实地调研的基础上,经过深入分析后认为,产业结构失衡是造成多数煤炭城市陷入困境的重要原因。进行产业结构的调整是促进其经济振兴和实现可持续发展的重要举措,目前,制约煤炭城市产业结构调整的因素主要有体制性和非体制性两大类,文章对此进行了分析,并提出了产业结构调整的原则,作者认为,加强产业结构调整的统筹规划,优先发展主导产业,打破条块分割,增量与存量调整并举,实行团党委有企业的产权制度改革等是进行产业结构调整的基本对策。 相似文献
863.
等高固氮植物篱技术——山区坡耕地保护开发利用的有效途径 总被引:22,自引:1,他引:22
固氮植物篱近年来被热带地区用作防治坡耕地的水土流失和肥力退化的有效手段。在地处亚热带金沙江干热河谷区的中国科学院成都生物研究所宁南持续发展实验站的研究结果表明:与传统顺坡耕作方式相比,利用新银合欢(L.1eucocephala)或山毛豆(T.candida)在坡耕地上每隔4m培植高密度的双行等高植物篱可使坡耕地的径流量平均减少49.6%以上,土壤侵蚀及其产生的养分流失均减少98%以上,土壤有机质、全氮、阳离子交换量等养分有很大程度的恢复和改善。农作物产量得以维持和提高,这说明等高固氮植物篱对我国亚热带坡耕地的水土保持和土壤改良同样具有十分良好的效果。 相似文献
864.
865.
方差──协方差分量的LS估计和有偏估计 总被引:1,自引:0,他引:1
本文利用离差一均值对应方法,提出了随机模型中方差一协方差分量的最小二乘估计、岭估计、广义岭估计和Stein压缩估计等有偏估计,并研究了其优良性质。 相似文献
866.
867.
高士纯 《武汉大学学报(信息科学版)》1996,(1)
针对大型测量控制网给出了两种附有限制条件的间接分组平差的函数模型。利用分组平差理论及相关最小二乘原理,推导了该两种函数模型的平差计算及精度评定公式。 相似文献
868.
869.
四平市矿业产业结构调整原则与优化浅析 总被引:1,自引:0,他引:1
四平市已发现矿种48种,其中探明储量23种,已开发利用19种,依据矿业产业结构存在的主要问题,建议做如下调整;建立以省内优势矿产资源(银、锌、硫、玻璃用砂、玻璃用白云岩、硅灰石、膨润土)为龙头,以能源(石油、天然气、煤)为保证,以建材原料(水泥用灰岩、砖瓦用粘土、建筑石材)为骨干,其它矿产资源为辅的矿业产业结构体系,实现矿业增长方式的根本转变,以保持与四平市近期中长期地方国民经济发展规划中提出的增长速度同步。 相似文献
870.
Kai W. Wirtz 《Marine pollution bulletin》2001,43(7-12):209-214
Simulation tools used for management purposes should fulfill several conditions by being computationally fast, user-friendly, realistic, generic and reliable. These traits are often counteracting since they simultaneously demand for model complexity as well as simplicity. Here we develop a strategy to overcome this general problem of environmental modelling for management use. Major ingredients are model analysis and reduction as new core components of the modelling process. In detail, a set of combined methods is proposed. Within a large class of models the set allows for automatically exploring model behaviour and for aggregating fine scale process knowledge together with spatio temporal resolution. Applications to a huge aquatic European regional seas ecosystem model (ERSEM), a complex photosynthesis model (PGEN) as well as a simple diagenetic model are presented. The analysis and aggregation methods provide first steps towards a new generation of decision support tools able to cope with an increase in scientific knowledge as well as management demands. 相似文献