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161.
时间地理学的起源,主要概念及其应用 总被引:24,自引:3,他引:21
时间地理学是瑞典地理学家哈格斯特朗及其领导的隆德大学研究小组提出的,最初应用于城市规划中的居民日常活动与设施规划的计算机模拟模型中。70年代末以前的时间地理学应用研究是沿哈格斯特朗的基本观点进行的,主要表现在对区域规划、人地关系及社会史的研究中。进入80年代以后的应用研究则在个人生活与社会结构关系、女性地理学、福利地理学及城市地域研究、城市交通规划等方面有创造性的展开。 相似文献
162.
163.
Solute transport in rivers and streams with hyporheic zone exchange and/or in-stream storage is typically affected by the prevailing flow rate. The research reported here focuses on stream tracer experiments repeated many times along the same Austrian (Mödlingbach) and Italian (Torrente Lura) channel reaches to characterize parameter dependency on flow rate. Both groups of data sets showed an increase of storage zone area and main stream area with discharge. In either case, a strong negative correlation was obtained between storage zone residence time and flow rate. From the Mödlingbach data, no clear relationship with Q emerged for the dispersion coefficient and the dead zone ratio, whereas Torrente Lura showed a clear positive correlation of the dispersion coefficient with the flow rate and a slightly negative Q-dependency for the dead zone ratio. Mödlingbach and Torrente Lura results are presented against the background of other repeat experiments reported in literature. 相似文献
164.
基于单次散射模型的尾波功率谱分析法,利用安徽省蒙城区域数字地震台1999年12月30日记录震中距35 km,M_S 4.1地震波形资料计算蒙城地震台周边半径约55 km范围内区域地球介质不同频率的Q值,发现0.5—20 Hz频率范围内,Q值随频率的变化关系近似服从幂函数关系Q_c=Q_0f~η,Q_0为1 Hz时的Q值,即Q_c=27.04f~(0.9952±0.0004),其中Q值在13—533范围内,平均值为273,η值在0.9952±0.004。结果表明,蒙城地震台附近范围内Q值具有较强的频域依赖性,与他人研究求得的Q作比较,平均值结果接近该Q值可以较好反映当地地球介质的品质因子;给出当地地震波传播介质的平均自由程为15 km,探讨介质的品质因子Q(Q_c)值的物理意义及应用,对研究本地区的地震活动习性及震后趋势预测具有重要意义。 相似文献
165.
《The Professional geographer》1986,38(4):430-457
Book Reviewed in this article: Latin America: Case Studies . Richard G. Boehm and Sent Visser Locality and Rurality: Economy and Society in Rural Regions . Tony Bradley And Philip Lowe The City and the Grassroots . Manuel Castells Geopolitics and Conflict in South America. Quarrels among Neighbors . Jack Child Post-Industrial America: A Geographical Perspective . David Clark Coastal Research: UK Perspectives . Malcolm W. Clark A Rural Policy for the EEC? Hugh Clout Peasant Agriculture in Assam: A Structural Analysis . M. M. Das . Environmental Change and Tropical Geomorphology . I. Douglas and T. Spencer Advances in Abandoned Settlement Analysis: Application to Prehistoric Anthrosols in Colombia, South America . Robert C. Eidt Measuring Culture . Jonathan L. Gross and Steve Rayner North America: A Human Geography . Paul Guinness and Michael Bradshaw A Geographical Bibliography for American Libraries . Chauncy D. Harris et al. Geography and the Urban Environment: Progress in Research and Applications, Vol. VI . D. T. Herbert and R. J. Johnston Changes in Global Climate: A Study of the Effect of Radiation and Other Factors During the Present Century . K. Ya . Kondrat'ev . Rural Development and the State: Contradictions and Dilemmas in Developing Countries . David A. M. Lea and D. P. Chaudhri The Martial Metropolis: U.S. Cities in War and Peace . Roger W. Lotchin The Climate of the Earth . Paul E. Lydolph . Weather and Climate . Paul E. Lydolph . Spatial Divisions of Labor: Social Structures and the Geography of Production . Doreen Massey . Panorama of the Soviet Union . N. Mikhailov . Soviet Armenia . K. S. Demirchian . USSR: Geography of the Eleventh Five-Year Plan Period . K. Spidchenko . Planung und Verwirklichung der Wiener Ringstrassenzone (Planning and Materialization of the Ringstrasse-Zone of Vienna). Kurt Mollik , Hermann Reining , Rudolf Wurzer . The American West Transformed: The Impact of the Second World War Gerald D. Nash . An Overview of the Survey of Income and Program Participation . Dawn Nelson , David Mc Millen, and Daniel Kasprzyk . Phenomenology, Science and Geography: Spatiality and the Human Sciences . John Pickles . Biological Diversification in the Tropics . Ghillean T. Prance Die Wanderviehwirtschaft im gebirgigen Westen der U.S.A. und ihre Auswirkungen im Naturraum . Gisbert Rinschede . Social and Economic Aspects of Radioactive Waste Disposal: Considerations for Institutional Management . World-Wide Weather . K. Takahashi Coastal Geomorphology in Australia . B. G. Thom Settlement System in Rural India: A Case Study of the Lower Ganga-Yamuna Doab . Ram Chandra Tiwari . Computer Programming for Geographers . David J. Unwin and John A. Dawson . Late Quaternary Environments of the Soviet Union . A. A. Velichko, ed . H. E. Wright , Jr. and C. W. Barnosky Ethics in Planning . Martin Wachs 相似文献
166.
Social change in rural China is to be understood as a complex interaction of global effects, state and regional actions and competing systems of valuation. An important implication of this model of path dependence is the development of distinctive forms of markets in different regions of the country. One such distinctive model that is emerging in southern Inner Mongolia is based on the independent commodity production of milk (on small dairy farms) for large, capitalist dairy corporations. Yet this production system is also being challenged by the emergence of large, capitalist dairy farms in this region. The outcome of the competition between these two forms of production will depend on locally specific trajectories of costs and opportunities. The long run evolution of this production system is thus not plannable in advance and is locally contingent. 相似文献
167.
Eco-dependency in Latin America 总被引:1,自引:0,他引:1
Jonathan R. Barton 《Singapore journal of tropical geography》2006,27(2):134-149
This article develops an argument around the perpetuation of socioeconomic development models based on non-renewable natural resource exploitation, weak management and regulation of renewables and the deterioration in environmental quality across different natural resources. It concludes that the structural constraints pointed out during the 1940–80 period by the dependentistas (advocates of the various theorizations of dependency) and to a lesser extent the cepalista structuralists (policy analysts at the United Nations Economic Commission for Latin America and the Caribbean) were alive and well in Latin America in the period 1980–2000. A theoretical case is made for the political economy reading of dependency into the realm of natural resources and environmental issues. It is argued that Latin American history and the region's more contemporary insertion into the global political economy has been determined by its use of natural resources and ongoing degradation of diverse environments. The conclusions emphasize the importance of responding to this historical condition, recognizing the concerns of the structuralists of the 1940s and 1950s and the threats highlighted by the dependentistas in the 1970s, but through the lens of contemporary changes. 相似文献
168.
不同贝龄毛蚶壳形态性状对体质量的影响 总被引:4,自引:0,他引:4
选取毛蚶(Scapharca subcrenata Lischke)1龄、2龄和3龄个体各100粒,分别测量壳长、壳高和壳宽等壳形态性状,并称其体质量,采用多元分析的方法分析了各表型性状间的相关性,以及壳形态性状对体质量的影响效果。结果表明,各性状间呈正相关,且达到极显著水平(P0.001);通径分析与决定程度分析的结果相似,不同贝龄期影响毛蚶体质量的主要因素是不同的,壳长是影响1龄毛蚶体质量的主要因素,壳长和壳宽是影响2龄毛蚶体质量的主要因素,且两者的共同决定系数最大(0.244),壳宽是影响3龄毛蚶体质量的主要因素,其与壳高的共同决定系数最大(0.230)。 相似文献
169.
磴口县景观格局演变特征及生态网络构建 总被引:2,自引:0,他引:2
城市生态基础设施是城市可持续发展的基础,西部干旱区生态脆弱性大,县域尺度的生态基础设施网络是保证干旱区城市稳定与发展的重要保障。在快速城市化的背景下,选择西部典型生态脆弱区磴口县为研究区,运用景观格局指数、景观转移网络及核密度分析等方法,分析景观格局演变,在此基础上确定生态源地并分级,基于Cost Path模型提取生态廊道与生态节点,构建城市化背景下基于景观格局演变的磴口县生态基础设施网络。结果表明:2014年磴口县域景观破碎化程度高,景观生态流流动性差,城市与建设用地、荒漠灌木林地、耕地、沙漠之间的转移情况决定了磴口县整体景观变化的特征,2001-2014年共存在28种景观转移关系;基于Cost Path模型构建的县域尺度生态基础设施优化网络共包含391块生态源地、47 466条生态廊道和799个生态节点。针对干旱区构建的县域尺度的城区防护型生态网络,能够为磴口县城市化发展提供重要保障,对干旱区城市生态规划具有重要的参考价值。 相似文献
170.
利用1980—1984年和2004—2020年锦州市农业气象观测站春玉米物候观测资料和气象观测资料,采用趋势系数、倾向率、相关分析和通径分析等方法,分析了锦州市春玉米生育期长度和水热条件的变化趋势,并探讨了锦州市春玉米生育期长度与水热条件的关系。结果表明:1980—1984年和2004—2020年锦州地区春玉米各生育期长度变化趋势不同,除抽雄期、成熟期和生殖生长期外,其他生育期长度均呈缩短的趋势。营养生长期长度极显著缩短,生殖生长期长度极显著延长,因此全生育期呈弱的延长趋势,变化不明显。春玉米各生育期水热条件变化趋势不同,热量条件变化显著,而水分条件变化不显著,多数生育期≥10℃活动积温(DT10)和生长度日(GDD)呈增加的趋势,其中抽雄期、成熟期和生殖生长期、全生育期热量条件呈极显著增加趋势,表明热量条件对春玉米生长发育影响最大。相关分析和通径分析表明,DT10和GDD对春玉米生育期长度影响最大,水分条件对春玉米生育期长度影响较小,其中出苗期、成熟期和全生育期长度与水分条件相关显著。可见,锦州地区水热因子之间相互制约、相互影响,共同影响春玉米的整个生育期。 相似文献