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李新通 《亚热带资源与环境学报》2007,2(4):41-48
综合利用Photoshop、Geoway、MapInfo、ArcView等软件提供的处理技术,通过对扫描得到的地形、土地利用和水土流失等要素图进行图像剪切、拼接、配准、采样、跟踪、调整以及属性表的维护等一系列处理步骤,建立了大比例尺小流域地理空间框架数据集,提供了小流域空间框架数据采集与应用的技术流程与方法,提出应用各种软件进行大比例尺空间框架数据处理过程中应当注意的各种细节问题.最后,以闽南丘陵地区草子坝小流域为例,利用ArcView的3D Analyst、Spatial Analyst、Geoprocessing等扩展模块以及MapInfo SQL查询功能,对流域空间框架数据进行处理,得到了用于比较精细空间尺度上表达流域三维地形模型、坡度、坡向、河流垂直剖面、晕渲,不同高程上的土地利用类型等专题应用结果. 相似文献
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我国土壤地球化学及其在农业生产中的意义 总被引：20，自引：0，他引：20
我国土壤地球化学特征受生物,气候,母质,地形及人为作用等因素影响,形成了我国独特的土壤地球化学类型和分布格局。不同地球类型,均有各自的元素丰度。土凶素与植物生长和人体健康的关系取决于土壤中元素的有效部分。 相似文献
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《Geophysical Journal International》1990,103(3):769-775
Book Reviews in this article:
Seismology and Plate Tectonics David Gubbins, Cambridge University Press, Cambridge , 1990, 339pp, hard cover ISBN 0521 371414, £35, US $59.5, soft cover ISBN 0521 379954 £13.95, US $27.95.
Developments in four-dimensional geodesy. Lecture Notes in Earth Sciences, vol. 29 F. K. Brunner and C. Rizos (eds), Springer-Verlag, Berlin , 1990, x + 264, ISBN 3-540-52332-4, 0-387-52332-4, soft cover DM 62.
Theory of satellite geodesy and gravity field determination. Lecture Notes in Earth Sciences, vol. 25 F. Sansó and R. Rummel (eds), Springer-Verlag, Berlin , 1989, xii + 491 pp, ISBN 3-540-51528-3, 0-387-51528-3, soft cover DM 98.
Planetary Volcanism–A Study of Volcanic Activity in the Solar System Peter Cattermole, Ellis Horwood Publishers Ltd, Chichester , 1990, 443pp, ISBN 0745 805078, £35.
Sediment acoustics Robert. D. Stoll, Springer-Verlag, Berlin , 1989, 155 pp, ISBN 3-540-97191-2, soft cover DM 34. 相似文献
Seismology and Plate Tectonics David Gubbins, Cambridge University Press, Cambridge , 1990, 339pp, hard cover ISBN 0521 371414, £35, US $59.5, soft cover ISBN 0521 379954 £13.95, US $27.95.
Developments in four-dimensional geodesy. Lecture Notes in Earth Sciences, vol. 29 F. K. Brunner and C. Rizos (eds), Springer-Verlag, Berlin , 1990, x + 264, ISBN 3-540-52332-4, 0-387-52332-4, soft cover DM 62.
Theory of satellite geodesy and gravity field determination. Lecture Notes in Earth Sciences, vol. 25 F. Sansó and R. Rummel (eds), Springer-Verlag, Berlin , 1989, xii + 491 pp, ISBN 3-540-51528-3, 0-387-51528-3, soft cover DM 98.
Planetary Volcanism–A Study of Volcanic Activity in the Solar System Peter Cattermole, Ellis Horwood Publishers Ltd, Chichester , 1990, 443pp, ISBN 0745 805078, £35.
Sediment acoustics Robert. D. Stoll, Springer-Verlag, Berlin , 1989, 155 pp, ISBN 3-540-97191-2, soft cover DM 34. 相似文献
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YueFang Li Zhen Li Ju Huang Giulio Cozzi Clara Turett Carlo Barbante LongFei Xiong 《寒旱区科学》2017,9(6):568-579
Although previous investigations of the trace elements in snow and ice from the Qinghai-Tibetan Plateau obtained interesting information about pollution from human activities on the plateau, most were based on traditional acidification methods. To emphasize the influence of the different sample-preparation methods on the records of trace elements and rare earth elements, snow samples were collected from glaciers on the Qinghai-Tibetan Plateau in China and prepared using two methods: traditional acidification and total digestion. Concentrations of 18 trace elements (Al, Ti, Fe, Rb, Sr, Ba, V, Cr, Mn, Li, Cu, Co, Mo, Cs, Sb, Pb, Tl, and U), along with 14 rare earth elements (REEs: La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu), Y, and Th in the snow samples, were measured using inductively coupled plasma-sector field mass spectrometry (ICP-SFMS). The results showed that the mass fraction of the trace elements (defined as ratio of concentration in the acid-leachable fraction to that in the digested sample) such as Mo, Ti, Al, Rb, and V, varied from 0.06 to 0.5. The mass fraction of other trace elements varied from about 0.6 to more than 0.9; those of the REEs, Y, and Th varied from 0.34 to 0.75. Lower mass fractions will lead to an overestimated contribution of other sources, especially human activities, and the underestimated fluxes of these trace elements (especially REEs, Y, and Th, as well as dust) if the REEs are used as the proxy for the crust dust. The two sample-preparation methods exhibited different REE normalized distribution patterns, REE ratios, and provenance-tracing results. The REE normalized distribution patterns and proxies in the digested samples are more reliable and integrated than those found in traditional acidification method for dust-provenance tracing. 相似文献
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该文分析重庆市地质、地貌、矿产、气候、水文、生物、土壤等自然地理背景和行政区划、人口、科教、城镇、工农业、交通、通讯、商贸、旅游等人文地理背景 ,总结重庆市地理区位的七大特征。并提出重庆市带动西部经济发展的若干建议。 相似文献
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三江源区生态型产业的发展与示范区建设思路 总被引：1，自引：0，他引：1
从三江源地区生态保护与区域建设的双重目标出发,分析了三江源地区经济发展与产业结构的基本特征。首先,分析了三江源自然保护区发展生态产业在我国西部生态型产业发展与生态环境建设中的战略影响、在青藏高原生态型产业发展与生态环境建设中的战略影响及在青海省生态型产业发展与生态环境建设中的战略影响,阐明三江源地区发展生态型产业的重大意义;接着分析三江源地区经济社会的基本特征,发现三江源地区由于地处高原地区,气候高寒干燥,并将三江源地区经济发展水平和青海省及全国发展水平作比较,认为三江源地区的经济发展表现出脆弱独特的高寒降效特征。分析该地区经济结构,发现三江源地区经济结构表现出粗放落后的经济特性,产业结构过分单一,地区发展基本上是依靠农牧经济,由于过分的依赖畜牧业和采矿业等资源开发型产业,本地资源开发很大程度上只进行初步利用,资源的深加工和再利用程度低,各产业链单一、短小,前向产业、后向产业和侧向产业发展滞后,造成中下游产业不发育,产业发展呈现封闭性、源头性、粗放性的特征。再者,该地区发展畜牧业经济产生的效益远小于生态环境破坏所造成的生态经济效益,旅游经济发展中旅游设施和开发靠基本靠外来投资,实际上造成经济效益在地区经济贡献中流失的实际情况,经济发展表现出典型的投入漏出特性。另外,从三江源地区的人口承载统计数据发现,该地区长期处于人畜超载特性,人口超载和利益驱动加剧地区脆弱生态环境的恶化。针对当地实际情况,文章提出了三江源地区生态型产业发展的基本思路与重点。整体发展思路立足于生态地区生态保护,从保护与可持续发展的双重角度出发,针对三江源保护区的特殊性和生态-生产-生活承载力,尊重自然规律和科学发展观,分阶段、分层次(核心层、缓冲层、试验层、外未层)提出三江源自然保护区产业发展的总体定位、发展目标、保护重点与发展方向,进而提出与资源优化配置及生态环境建设相适应的生态型产业体系和产业结构培育方案,建设若干个不同类型的示范区,推进三江源自然保护区国民经济的生态化和经济社会活动的生态化。并对建设方案的实施过程进行动态监测评估,对实施效果进行滚动预警。把三江源自然保护区建设成为生态、生产、生活共同繁荣的自然保护区、国家级可持续发展实验区和国家循环经济示范区。提出产业结构调整中“三个转变”的整体思路。即引导产业结构由单一畜牧业向林牧业-加工业-旅游业的多元化生态产业结构转变,建立生态型产业体系;引导产业结构由投入楼出型向投入产出型转变,推行集约型经济增长方式;引导产业结构由生产-生活型向生态-生产-生活型转变,推进国民经济生态化。进而提出要立足生态资源优势,培育和延伸生态型产业链,选择优化现代草畜业、现代医药和生态旅游业为主的支柱产业,建立资源节约型、环境友好型和生态型产业结构体系。文章进一步深入,提出生态农林牧业、生态工业和生态旅游业的发展思路与重点;生态型城镇建设目标与重点;与生态型产业体系和生态城镇建设相适应的生态移民的重点与方向以及生态能源建设与发展方向。鉴于三江源地区面积广大,地域辽阔,保护与开发过程中首先必须选择典型地区先行试验示范,在积累示范区成果和成功经验的基础上再逐步向周围广大地区因地制宜地推广。为此,建议根据三江源自然保护区综合保护与建设方案,选择重点建设地区和适宜建设地区,立足这些重点地区的资源禀赋条件及组合状况,经济社会发展基础、宗教民俗风俗、发展潜力和前景等,有选择、有重点地规划若干个生态经济示范区、生态重建示范区、生态旅游示范区和生态型小城镇建设示范区,对这些示范区提出详细规划设计方案,指明示范区内容、示范方向、示范重点和示范技术,提出各示范区的建设规模和建设模式。立足当地优势,提出要重点建设生态林牧业(种植、养殖、水利等)、生态工业(清洁生产)、生态旅游、生态城镇和生态科研产业示范区5种类型。为保障三江源地区从保护和建设的双重角度推进三江源地区生态型产业体系建设步伐,还从政策保障、基础设施建设、项目保障、空间管制、经费支持保障、动态滚动评估与滚动监测预警等方面提出了对策建议。 相似文献
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We investigate patterns of residential and nonresidential land use in 311 United States metropolitan (Extended Urban) areas in 2000 using four measures: intensity, compactness, mixing, and core-dominance. A cluster analysis revealed four distinctive groups of land use patterns: (1) Most-Intense, Least-Compact, Least-Mixed, More-Monocentric Development, (2) Less-Intense, Most-Compact, Less-Mixed, Less-Monocentric Development, (3) Least-Intense, Less-Compact, Most-Mixed, Most-Monocentric Development, (4) More-Intense, More-Compact, More-Mixed, Polycentric Development. Bivariate statistics demonstrated that geographic, historic, economic, demographic, and transport variables differentiate land use pattern types. Based on their multidimensional distinctions, we label the four types of metropolitan areas: Ascendants, Insulars, Redevelopers, and Cosmopolitans. 相似文献
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风沙运动理论体系的创建与研究 总被引：6，自引：2，他引：4
确定风、沙源、风沙流、下垫面和沙地地表形态是构成风沙运动体系的5个基本要素。确定风速的强弱、沙粒的走停、气流含沙量的盈亏、下垫面的扬抑作用和沙地地表的蚀积变化是这些基本要素各自参与风沙运动的主要表现特征。这些表现特征都能一分为二, 于是10个对立侧面的相互作用构成了风沙运动发展变化的总体。系统地研究这些侧面的组合关系、揭示它们相互促进相互制约的演变机理, 进而依其内在联系进行排序, 将其串联成一体, 并绘出图式, 这样便形成了名之曰"强、弱、扬、抑、走、停、盈、亏、蚀、积十纲辩证"的风沙运动理论体系。其中"强、弱、走、停、盈、亏、蚀、积八纲辩证"是本理论体系的核心。 相似文献
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民勤绿洲不同演化阶段白刺灌丛沙堆表面土壤理化性质研究 总被引：12，自引：3，他引：9
以民勤绿洲作为研究区域,对不同演化阶段灌丛沙堆表面土壤样品进行了采集和分析。结果表明,随着灌丛沙堆的不断演化,土壤性质发生了显著的变化。不同演化阶段灌丛沙堆表面颗粒组成仍以砂粒为主,从雏形阶段到稳定阶段,砂粒含量逐渐减少,在稳定阶段达到最小,pH值和砂粒的变化趋势一致,粉砂、粘粒、有机质、全氮、全磷、全钾、速效氮、速效磷和速效钾含量增加,在稳定阶段均达到最大;灌丛沙堆活化后,其砂粒含量和pH值重新出现增加趋势,而粉砂和粘粒的含量开始减少,有机质、全氮、全磷、全钾、速效氮、速效磷和速效钾含量也迅速下降;除稳定阶段迎风坡和背风坡有机质、全氮和全磷含量差异比较显著外,其他演化阶段不同坡向粒度和养分差异均不显著;有机质、全氮、速效氮的含量在灌丛沙堆演化过程中变幅最大,全磷和速效磷次之,全钾和速效钾的变幅最小。 相似文献
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空间数据挖掘技术研究进展 总被引：22，自引：0，他引：22
空间数据具有海量、非线性、多尺度、高维和模糊性等复杂性特点,空间数据挖掘技术是对空间数据中非显性的知识、空间关系等模式的自动提取。该文从空间数据挖掘的知识类型、方法、体系结构、过程以及与GIS系统集成等方面对其进行综述。重点阐述空间特征及区分规则、空间分类及聚类规则、空间分布及关联规则、空间序列及演化规则等知识类型以及统计分析、机器学习、探索性数据分析、可视化分析等数据挖掘方法。通过对空间数据挖掘理论、应用和系统实现等方面研究方向、存在问题的分析,指出集数据库、知识库、专家系统、决策支持系统、可视化工具、网络等技术于一体的空间数据挖掘系统是其主要发展方向。 相似文献
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受地质条件和地理环境的影响和制约,新疆地质遗迹分布具有明显的空间分异特征。本文以影响地质遗迹空间格局的关键因素--深大断裂和大地构造单元为主要依据,首次建立了包括5个地质遗迹带、13个地质遗迹区和35个地质遗迹亚区的新疆地质遗迹三级区划系统,设计了地质遗迹的数量、级别、类型、保护开发条件等4类定量表征指标和8项具体指标因子,对新疆地质遗迹的空间格局特征进行全面刻画和定量表征,最终根据各项指标数值的优劣程度对二级区划单元进行分类,为基于地质遗迹资源与人地关系耦合的新疆地质遗迹保护开发布局研究奠定基础。结果表明,二级区划单元中北天山、西昆仑、南天山、北阿尔泰地质遗迹区为优异(Ⅰ级),吐哈、准中、塔东、东昆仑－阿尔金、中昆仑、塔西区为良好(Ⅱ级),南阿尔泰区为一般(Ⅲ级),准西、准东区为较差(Ⅳ级)。 相似文献
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Eric T. Karlstrom 《自然地理学》2013,34(4):301-327
A chronosequence of 17 soils in late Quaternary alluvium on Black Mesa, northeast Arizona, permits quantification of rates of pedogenesis in a semi-arid region. Based on 24 tree-ring, radiocarbon, and archaeological dates, soil ages range from about 100 to 20,000 to 30,000+ years. Data indicate that ochric, cambic, argillic, natric, and calcic horizons form within about 100, 500, 1000, 3000, and 15,000 years, respectively, whereas mollic epipedons form within 1000 years. Bk horizons with Stage I, I+, II+, and III carbonate morphologies form within about 1000, 4000, 10,000, and 15,000 years, respectively. Thickness of Bt and Bk horizons, and Harden profile development and clay accumulation index values increase in a linear manner with increasing soil age. High resolution dating suggests rates of pedogenesis on Black Mesa are rapid relative to those documented elsewhere in the southwest United States and in the Rocky Mountains. Rates of soil formation recorded on Black Mesa, however, necessarily incorporate the combined effects of slight variations in elevation, climate, vegetation, topography, and parent materials throughout the region, as well as the influence of additions of atmospheric dust at the soil surface. [Key words: soil, pedogenesis, soil geomorphology, Quaternary, Arizona.] 相似文献
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This study conducted computer-aided image analysis of land use and land cover in Xilin River Basin, Inner Mongolia, using 4 sets of Landsat TM/ETM+ images acquired on July 31, 1987, August 11, 1991, September 27, 1997 and May 23, 2000, respectively. Primarily, 17 sub-class land cover types were recognized, including nine grassland types at community level: F. sibiricum steppe, S. baicalensis steppe, A. chinensis + forbs steppe, A. chinensis + bunchgrass steppe, A. chinensis + Ar. frigida steppe, S. grandis + A. chinensis steppe, S. grandis + bunchgrass steppe, S. krylavii steppe, Ar. frigida steppe and eight non-grassland types: active cropland, harvested cropland, urban area, wetland, desertified land, saline and alkaline land, cloud, water body + cloud shadow. To eliminate the classification error existing among different sub-types of the same gross type, the 17 sub-class land cover types were grouped into five gross types: meadow grassland, temperate grassland, desert grassland, cropland and non-grassland. The overall classification accuracy of the five land cover types was 81.0% for 1987, 81.7% for 1991, 80.1% for 1997 and 78.2% for 2000. 相似文献
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在25 a生的马尾松林下分别套种1 a生的火力楠、闽粤栲、苦槠、格氏栲、青栲和拉氏栲幼苗,经过16 a的培育后形成了郁闭的针阔混交异龄林,分别以马-火（Pm-Mm）、马-闽（Pm-Cf）、马-苦（Pm-Cs）、马-格（Pm-Ck）、马-青（Pm-Cm）、马-拉（Pm-Cl）表示。对上述6种混交林的蓄积量、生物量、凋落物、物种多样性、土壤肥力等10个指标进行分析和综合,以揭示混交林的经济效益、生态效益和地力维持。在此基础上,应用层次分析法（AHP）确定各指标的权重,构建多目标决策模型,对混交林综合效益进行了评价。根据综合评价值的大小,各混交林的优劣顺序为：马-闽→马-苦→马-拉→马-青→马-格→马-火,从而为马尾松混交模式的选择提供科学依据。 相似文献
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An integrated program, “Microbiological and ecological responses to global environmental changes in polar regions” (MERGE), was proposed in the International Polar Year (IPY) 2007–2008 and endorsed by the IPY committee as a coordinating proposal. MERGE hosts original proposals to the IPY and facilitates their funding. MERGE selected three key questions to produce scientific achievements. Prokaryotic and eukaryotic organisms in terrestrial, lacustrine, and supraglacial habitats were targeted according to diversity and biogeography; food webs and ecosystem evolution; and linkages between biological, chemical, and physical processes in the supraglacial biome.MERGE hosted 13 original and seven additional proposals, with two full proposals. It respected the priorities and achievements of the individual proposals and aimed to unify their significant results. Ideas and projects followed a bottom-up rather than a top-down approach. We intend to inform the MERGE community of the initial results and encourage ongoing collaboration. Scientists from non-polar regions have also participated and are encouraged to remain involved in MERGE.MERGE is formed by scientists from Argentina, Australia, Austria, Belgium, Brazil, Bulgaria, Canada, Egypt, Finland, France, Germany, Italy, Japan, Korea, Malaysia, New Zealand, Philippines, Poland, Russia, Spain, UK, Uruguay, USA, and Vietnam, and associates from Chile, Denmark, Netherlands, and Norway. 相似文献
18.
通过检索美国科学引文索引(SCI)、社会科学引文索引(SSCI)、工程索引(EI)、Scopus等国际期刊数据库以及相关学术组织网站中列举的国际地理期刊,整理和分析国际上区域研究期刊的基本信息,包括刊名、检索收录机构、刊期、出版机构、创刊年份和期刊网站六大基本信息。截至2016年,全球已有20个国家共出版了52种专门刊发区域研究的期刊。其中,12种区域研究期刊被SSCI收录。区域研究期刊的语种涵盖中文、英文、日文、法文、德文、俄文、波兰文、意大利文、西班牙文、葡萄牙文10种文字。最后,分析了区域研究期刊快速发展的主要原因。 相似文献
19.
《The Journal of geography》2012,111(8):504-505
Abstract MEKONG… A RIVER OF ASIA, Public Relations Dept., 50 West 50th Street, New York, New York, 30 minutes, 16mm, sound, color, no date. Free loan. DAIRY—FARM TO DOOR, Charles Cahill and Associates, 5746 Sunset Boulevard, Hollywood, California 90046, 10 minutes, 16mm, sound, color and black and white, 1965. $120 and $65. NORTH AMERICA: THE CONTINENT, Coronet Films, 65 East South Water Street, Chicago 1, Illinois, 14 minutes, 16mm, sound, color and black and white, 1965. Collaborator: Earl B. Shaw. MODERN FRANCE: THE LAND AND THE PEOPLE (Second Edition) Coronet Films, 65 East South Water Street, Chicago 1, Illinois, 14 minutes, 16mm, sound, color and black and white, 1965. $120 and $60. Collaborator: Clyde F. Kohn. LIFE ZONES OF THE CENTRAL ROCKIES, International Film Bureau, Inc., 332 South Michigan Ave., Chicago 4, Illinois, 21 minutes, 16mm, sound, color, 1965. $195. Produced by Walter H. Berlet. WATER HARVESTING, LeMont Films, P.O. Box 63, Northridge, California 91323, 15 1/2 minutes, 16mm, sound, color, no date. $168. 相似文献
20.
土壤有效态Cd、Cu、Pb的分布特征及影响因素研究 总被引：12，自引：0，他引：12
采集126个表层土壤样品分析了江苏省昆山市土壤有效态Cd、Cu、Pb的分布特征,并采用相关系数、通径系数和决策系数综合研究重金属有效态的含量影响因素。研究结果表明,昆山市土壤受有效态Cd、Cu和Pb的风险较大,生物有效性系数分别达63.75%,19.17%和13.51%。不同土地利用方式中交通用地的生物有效性显著高于其它各土地利用类型。随着剖面层次的下降,重金属有效态含量和生物有效性逐渐减小。土壤重金属总量对有效态均具有最大的正向影响作用,有机质对有效态含量均为较大的正向作用,FeOx含量通过吸附固持重金属离子对有效态含量也有较大负作用。 相似文献