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991.
基于2010年《山东统计年鉴》和全国第六次人口普查数据,本文以县域为研究单元,通过空间自相关分析人口的空间分布模式,运用因子分析和Pearson相关分析探究人口空间分布模式的影响因素。研究结果表明:山东省人口分布呈现"东北-西南"的空间分布模式,人口空间分布整体上呈现显著的空间集聚,主要集中在青岛市的中心城区;经济增长因素和地形条件是山东省人口空间分布模式形成的主要推动力。 相似文献
992.
陆内克拉通盆地是我国重要的含油气盆地类型之一,其层序地层学研究相对薄弱.以我国典型的陆内克拉通盆地-鄂尔多斯盆地山西组的层序地层学研究为例,提出陆内克拉通盆地长期持续退积、短期进积"溯源退积"层序构型的模式.其涵义是指陆内克拉通盆地所形成的三级层序的层序构型均以LST为主,TST和HST相对不发育,对应的基准面旋回具有长期持续退积(水进)、短期进积(水退)旋回特征;不同级别层序地层格架控制下的砂体,自下而上(从老到新),具有向北部物源区依次退积叠置的"溯源退积"特征. 相似文献
993.
B. J. J. Embleton 《Australian Journal of Earth Sciences》2013,60(1-2):121-122
Volcanic rocks, mainly of intermediate composition, occupy several basins within the rift zone along which the Yangtze River flows in its lower reaches. Potassium‐argon (K‐Ar) age measurements on minerals and whole rock samples from lavas and syenitic intrusives in the Lujiang‐Tzungyang volcanic basin range from 131 to 123 m.y., and biotites from two lavas in the Nanjing‐Wuhu basin have measured ages of 127 and 130 m.y. Incremental heating experiments by the 40Ar/39Ar method on biotite from two volcanic rocks, one from each basin, yield simple age spectra with plateau ages of 129 to 130 m.y. These data provide evidence that the two biotites have remained undisturbed since crystallisation. The combined results show that volcanism was contemporaneous within the two basins in the Early Cretaceous. Vol‐canism in the Yangtze Volcanic Zone is thought to be related to adjustments within the Eurasian plate as a consequence of collision between the earlier Pacific (Kula) plate and the Eurasian plate. 相似文献
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996.
《The Professional geographer》2013,65(4):430-435
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 McMillen, 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
997.
Patrick Laube Matt Duckham Marimuthu Palaniswami 《International journal of geographical information science》2013,27(2):273-292
This article presents an algorithm for decentralized (in-network) data mining of the movement pattern flock among mobile geosensor nodes. The algorithm DDIG (Deferred Decentralized Information Grazing) allows roaming sensor nodes to ‘graze’ over time more information than they could access through their spatially limited perception range alone. The algorithm requires an intrinsic temporal deferral for pattern mining, as sensor nodes must be enabled to collect, memorize, exchange, and integrate their own and their neighbors' most current movement history before reasoning about patterns. A first set of experiments with trajectories of simulated agents showed that the algorithm accuracy increases with growing deferral. A second set of experiments with trajectories of actual tracked livestock reveals some of the shortcomings of the conceptual flocking model underlying DDIG in the context of a smart farming application. Finally, the experiments underline the general conclusion that decentralization in spatial computing can result in imperfect, yet useful knowledge. 相似文献
998.
Changes in precipitation patterns and inputs have the potential to cause major changes in productivity, composition, and diversity of terrestrial plant communities. Vegetation response to altered timing of precipitation was assessed during a 7-year experiment in an Artemisia tridentata spp. wyomingensis community in the northern Great Basin, USA. Four permanent rainout shelters excluded natural rainfall, with seasonal distribution of precipitation controlled with the use of an overhead sprinkler system. Precipitation treatments under each shelter were WINTER, SPRING, and CURRENT. The WINTER treatment received 80% of its water between October and March; in the SPRING treatment 80% of total water was applied between April and July; and the CURRENT treatment received precipitation matching the site's long-term (50 years) distribution pattern. A CONTROL treatment, placed outside each shelter replicate, received natural precipitation inputs. CURRENT, WINTER, and CONTROL treatments had similar in soil water-content patterns and thus, there were few consistent differences in vegetation response. The SPRING treatment resulted in more bare-ground and lower plant productivity compared to other shelter treatments. This result contrasted with our initial hypothesis that shallower-rooted grasses would gain a competitive advantage over shrubs if precipitation was shifted from winter to spring. Our results also demonstrated the resilience of these communities to climate perturbation as many of the vegetation shifts did not begin until the fourth year after treatments were applied. 相似文献
999.
The oil migration patterns in porous medium are discussed based on the results of diphasic expulsing experiments. In the experiments, dyed kerosene was used as expulsing phase to expulse water saturated in a glass cylinder filled with sorted glass beads. Two series of experiments were done: one with different initial oil column heights and the other with variable oil injection rates. Three secondary migration patterns, including stable displacement pattern, fingering pattern and stringing pattern may be recognized in each series of experiments. Two classic dimensionless parameters, the modified Bond number and the Capillary number, were used to construct a phase diagram that may characterize the patterns. A new method was proposed to calculate the Darcian velocity of moving kerosene in the cylinder when only buoyancy force acts. It is found that when Darcian velocity is used to get the two dimensionless parameters, the data from both series of experiments, as well as those obtained from literatures, may be reasonably drawn in a phase diagram to identify the three migration patterns. 相似文献
1000.
This paper provides the first analysis at the sub-municipality scale of the relationships between population densities and deforestation in the Brazilian Amazon between 2000 and 2010. We use the database on deforestation published by the Brazilian space research center (INPE) and the population census data released by the federal geographical and statistical agency IBGE at their finest scale: the census tract level. By crossing the population density and deforestation variables, we identify ten human settlement patterns in the Amazon. There are low-low and high-high classes of population density and deforestation, but also low-high and high-low classes. This analysis helps understand the low overall relations in the Amazon for population and deforestation. We emphasize the expansion of large-scale agriculture and cattle ranching as causing the depopulation of rural areas while in many regions of the Amazon quite strong population densities coexist with relatively low extents of deforestation. Such findings stress the need to implement case-specific public policies in these regions in order to encourage human presence compatible with the conservation of forest cover and biodiversity. We also confirm the importance of the Amazon urbanization process, including the ‘discrete urbanization’ of rural areas, and the need to better recognize the distinct social and environmental problems of urban areas. 相似文献