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771.
四川森林的地域分异特点 总被引:1,自引:1,他引:0
四川的地形主要是山地,因而四川森林属山地类型,其中以松Pinaceae林和栎Fa-gaceae林为主。松林和栎林在四川森林中具有代表性。在地理分布上四川森林的地域分异极为明显。根据森林的地域分异特点,将四川林区划分为9个森林分布区。 相似文献
772.
《The Professional geographer》1986,38(1):105-130
Book Reviewed in this article: Unfairly Structured Cities . Blair Badcock Religion and Rural Revolt . Janos M. Bak and Gerhard Benecke The Industrial Geography of Canada . Anthony Blackbourn and Robert G. Putnam The Cuban-American Experience, Culture, Images, and Perspectives. Thomas D. Boswell and James R. Curtis Quaternary Paleoclimatology . R. S. Bradley Development and Crisis in Brazil, 1930–1983 . Luiz Bresser Pereiras Centres of Origin in Biogeography . John C. Briggs Analytical Urban Geography . Martin Cadwallader Geomorphology . Richard J. Chorley , Stanley A. Schumm, and David E. Sugden South Africa: The Impact of Past Geographies . A. J. Christopher The Geography of Underdevelopment. A Critical Survey . D. K. Forbes Health Care in Developing Countries . Wilbert M. Gesler Place to Grow Old: The Meaning of Environment in Old Age . Stephen M. Golant The Emerging Marine Economy of the Pacific . Chennat Gopalakrishnan An Introduction to Agricultural Geography . David B. Grigg The Soviet Union: A Geographical Study . G. Melvyn Howe Geographical Aspects of Health: Essays in Honour of Andrew Learmonth . N. D. Mc Glashan and J. R. Blunden Physical Geography: A Landscape Appreciation . Tom L. Mc Knight Mountain Experience. The Psychology and Sociology of Adventure. Richard G. Mitchell Jr . Systematic and Regional Biogeography. Stanley A. Morain The Economic Transformation of American Cities. T. J. Noyelle and T. M. Stanback , Jr . Normal Accidents: Living With High-Risk Technologies. Charles Perrow Vanishing Farmland: A Legal Solution for the States. Sarah E. Redfield Applied Methods of Regional Analysis: The Spatial Dimensions of Development Policy. Dennis A. Rondinelli Urbanization in Romania. A Geography of Social and Economic Change Since Independence. Per Ronnas Statistical Techniques in Geographical Analysis. Gareth Shaw and Dennis Wheeler The Granite Garden: Urban Nature and Human Design. Anne Whiston Spirn Political Geography: Recent Advances and Future Directions. Peter Taylor and John House Geographia y Medio Ambiente. Manuel Valenzuela -Rubío Nãgara and Commandery: Origins of the Southeast Asian Urban Traditions. Paul Wheatley The Common Fisheries Policy of the European Community. Mark Wise Geography and Gender. Women and Geography Study Group of the IBG Technological Hazards. D. J. Zeigler , J. H. Johnson , S. D. Brunn 相似文献
773.
东部三大经济区城市流动人口的多维度社会融入及其地区差异 总被引:2,自引:0,他引:2
以流动人口集中的京津冀、长三角和珠三角三大经济区35个城市2012年流动人口动态监测数据为基础,采用均方差权值法,综合经济、社会、心理、制度和公共服务5个维度构建衡量流动人口社会融入的指标体系,在此基础上计算和比较了三大经济区及其35个城市流动人口各维度社会融入指标和社会融入综合水平得分及其地区差异。研究结论显示,社会融入综合水平得分由高到低依次是京津冀、长三角、珠三角。同一地区流动人口的融入状况在各个维度不均衡,京津冀地区流动人口社会维度的融入程度最高,制度维度融入程度最低;长三角地区流动人口的心理维度融入居前列,但社会维度融入位列最后;珠三角地区流动人口的社会维度融入程度最高,公共服务维度融入不足。此外,就整体而言,三大地区流动人口的工作强度大、交往对象固化于流动人口、在流入地长期居住意愿多数仍处于举棋不定的状态;三大地区都存在落实居住证/暂住证制度和流动人口享有城镇医保等方面较为薄弱等诸多问题并共同制约着流动人口真正融入流入城市。为此,需要在政策制定中予以关注。 相似文献
774.
Florian Heinz Ralf Hartmut Güting 《International journal of geographical information science》2018,32(9):1737-1769
Moving object databases are designed to store and process spatial and temporal object data. An especially useful moving object type is a moving region, which consists of one or more moving polygons suitable for modeling the spread of forest fires, the movement of clouds, spread of diseases and many other real-world phenomena. Previous implementations usually allow a changing shape of the region during the movement; however, the necessary restrictions on this model result in an inaccurate interpolation of rotating objects. In this paper, we present an alternative approach for moving and rotating regions of fixed shape, called Fixed Moving Regions, which provide a significantly better model for a wide range of applications like modeling the movement of oil tankers, icebergs and other rigid structures. Furthermore, we describe and implement several useful operations on this new object type to enable a database system to solve many real-world problems, as for example collision tests, projections and intersections, much more accurate than with other models. Based on this research, we also implemented a library for easy integration into moving objects database systems, as for example the DBMS Secondo (1) (2) developed at the FernUniversität in Hagen. 相似文献
775.
Spatiotemporal characteristics of urban air quality in China and geographic detection of their determinants 总被引:4,自引:2,他引:2
Ambient air pollution brought by the rapid economic development and industrial production in China has exerted a significant influence on socio-economic activities and public health, especially in the densely populated urban areas. Therefore, scientific examination of regional variation of urban air quality and its dominant factors is of great importance to regional environmental management. Based on daily air quality index (AQI) datasets spanning from 2014 to 2016, this study analysed the spatiotemporal characteristics of air quality across different regions throughout China and ascertained the determinants of urban air quality in disparate regions. The main findings are as follows: (1) The annual average value of the urban AQI in China decreased from 2014 to 2016, indicating a desirable trend in air quality at the national scale. (2) The attainment rate of the urban AQI exhibited an apparent spatially stratified heterogeneity, wherein North China retained a high AQI value. The increase of Moran’s I Index reported an apparent spillover effect among adjacent regions. (3) Both at the national and regional scales, the seasonal tendency of air quality in each year is similar, wherein good in summer and relatively poor in winter. (4) Results drawn from the Geographic Detector analysis show that dominant factors influencing AQI vary significantly across urban agglomerations. Topographical and meteorological variations in urban areas may lead to complex spatiotemporal variations in pollutant concentration. Whereas given the same natural conditions, the human-dominated factors, such as industrial structure and urban form, exert significant impacts on urban air quality.The spatial spillover effects and regional heterogeneity of urban air quality illustrated in this study suggest the governments and institutions should set priority to the importance of regional cooperation and collaboration in light of environment regulation and pollution prevention. 相似文献
776.
Environmental concern is crucial as bottom-up support for policies that aim to tackle the multiple ecological crises. This paper investigates which characteristics of 206 European regions are robust drivers of generalized environmental concern. To this end, 25 Eurobarometer survey waves between 2009 and 2019 were combined with measures of the regional economy, population, geography, environmental quality, and meteorological events. Bayesian model averaging is used to systematically account for model uncertainty in the estimation of partial correlations. The results indicate that environmental concern increases with income level, a more equal distribution of income and wealth, and a less greenhouse gas-intensive industrial sector. Furthermore, regions with younger and better educated populations exhibit higher levels of environmental concern. In terms of environmental characteristics, both geographical vulnerability to natural hazards and meteorological events affect environmental concern. The results highlight the importance of the socio-economic and environmental context of opinion formation and have implications for designing and communicating environmental policies. 相似文献
777.
778.
多模态地理大数据时空分析旨在融合地理大数据的多模态信息发现有价值的时空分布规律、异常表现、关联模式与变化趋势,是全空间信息系统的核心研究内容,并有望成为推进地理学人地关系研究的重要突破口。为应对地理大数据时代的新机遇与挑战,本文围绕4类核心的时空分析方法(时空聚类分析、时空异常分析、时空关联分析与时空预测分析),系统归纳了国内外研究现状,探讨了时空分析中多尺度建模、多视角协同、多特征认知与多特性表达的研究难点。进而,介绍了多模态地理大数据时空聚类、异常、关联与预测分析模型,更加全面、客观、精准地认知与理解时空大数据中潜在的地理知识,并且能够在气象环境监测、公共安全管理、城市设施规划等多个应用领域发挥关键作用。 相似文献
779.
Christopher J. Eastoe Barry J. Hibbs Alfredo Granados Olivas James F. Hogan John Hawley William R. Hutchison 《Hydrogeology Journal》2008,16(4):737-747
Stable isotope data for the Hueco Bolson aquifer (Texas, USA and Chihuahua, Mexico) distinguish four water types. Two types relate to recharge from the Rio Grande: pre-dam (pre-1916) river water with oxygen-18 and deuterium (δ18O, δD, ‰) from (?11.9, ?90) to (?10.1, ?82), contrasts with present-day river water (?8.5, ?74) to (?5.3, ?56). Pre-dam water is found beneath the Rio Grande floodplain and Ciudad Juárez, and is mixed with post-dam river water beneath the floodplain. Two other types relate to recharge of local precipitation; evidence of temporal change of precipitation isotopes is present in both types. Recharge from the Franklin and Organ Mountains plots between (?10.9, ?76) and (?8.5, ?60) on the global meteoric water line (GMWL), and is found along the western side of the Hueco Bolson, north of the Rio Grande. Recharge from the Diablo Plateau plots on an evaporation trend originating on the GMWL near (?8.5, ?58). This water is found in the southeastern Hueco Bolson, north of the river; evaporation may be related to slow recharge through fine-grained sediment. Pre-dam water, recognizable by isotope composition, provides information on groundwater residence times in this and other dammed river basins. 相似文献
780.
基于天桥的几何与属性特征,提出了一种志愿者地理信息中自动识别天桥的方法。天桥从几何结构上可分为主桥和附属设施两个部分,主桥部分特征鲜明,可以视为两类分类问题,依据其几何特征和属性特征构建特征空间,利用支持向量机的方法进行识别;附属设施部分可依据已识别的天桥主桥,按照路段的长度、属性等判定规则进行识别,从而完成整个天桥的自动识别。以北京市OpenStreetMap(osm)数据进行试验验证的结果表明,本文提出的方法能有效地识别出志愿者地理信息中的典型天桥结构,可以为志愿者地理信息道路网的多尺度建模与化简、步行导航等提供帮助。 相似文献