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81.
河流型国家湿地公园功能区规划方法探析 总被引:2,自引:2,他引:0
国家湿地公园总体规划的核心工作是功能区划分,功能区划分直接影响到相关的保护和恢复工程规划,也为湿地公园的建设布局指明了方向。功能区规划前实地调查工作的重点为理清水系脉络、确定核心资源、找出威胁因子,归纳了4种适合于河流型国家湿地公园功能区划的区划方式,为湿地公园功能区规划提供参考模式。 相似文献
82.
We report for the first time the occurrence of polygonal faults in sandstone, which is compelling given that layer-bound polygonal fault systems have been observed so far only in fine-grained sediments such as clay and chalk. The polygonal faults are shear deformation bands that developed under shallow burial conditions via strain hardening in dm-wide zones. The edges of the polygons are 1–5 m long. The shear deformation bands are organized as conjugate faults along each edge of the polygon and form characteristic horst-like structures. The individual deformation bands have slip magnitudes ranging from a few mm to 1.5 cm; the cumulative average slip magnitude in a zone is up to 10 cm. The deformation bands heaves, in aggregate form, accommodate a small isotropic horizontal extension (strain <0.005). The individual shear deformation bands show abutting T-junctions, veering, curving, and merging where they mechanically interact. Crosscutting relationships are rare. The interactions of the deformation bands are similar to those of mode I opening fractures. The documented fault networks have important implications for evaluating the geometry of km-scale polygonal fault systems in the subsurface, top seal integrity, as well as constraining paleo-tectonic stress regimes. 相似文献
83.
三江源地区秋季典型多层层状云系的飞机观测分析 总被引:4,自引:0,他引:4
利用三江源地区一次机载粒子测量系统PMS(Particle Measuring Systems)的分层垂直探测资料,系统研究了该地区秋季典型多层层状云系的微物理特性,结果表明:(1)云系由4层云层组成,Cs(卷层云)和上层As(高层云)为冰云,下层As和Sc(层积云)为过冷混合态云。下层As的云粒子浓度和过冷水含量最大,Sc的云粒子尺寸及谱宽最大,且具有较明显的地区特性;(2)Sc(下层As及对流泡)中中值直径在3.5~18.5 μm(3.5~ 21.5 μm)之间的云粒子为液相,中值直径大于21.5 μm(24.5 μm)的云粒子为冰相;(3)混合态云中高过冷水区与低过冷水区云的粒子谱分布差异明显,Sc高过冷水区有较明显的淞附增长现象;(4)Sc、下层As云底、对流泡顶高过冷水区的云滴有效半径依次增加。Sc高过冷水区的过冷水含量比率均值及标准差为69.9±19.4%,且与过冷水含量存在一定的关联性;下层As云底高过冷水区的过冷水含量比率无明显变化,其均值及标准差为89.2±8.1%;(5)混合态云各高度层FSSP(前向散射粒子谱探头)平均粒子谱均为单峰型伽玛分布,混合态云和冰云各高度层2DC(二维灰度云粒子探头)平均粒子谱基本上都为负指数型分布。 相似文献
84.
Little attention has been paid thus far to the experiences of developed countries in adapting to climate change. This article addresses this research gap by providing an assessment of broad trends in progress on planning and implementing adaptation in developed countries. Primary inputs are the National Communications (NCs) by these countries to the United Nations Framework Convention on Climate Change (UNFCCC), although the article also discusses illustrative examples of recent adaptation activities that have not been covered in the NCs. NCs reflect ‘whole government’ perspectives and follow a standardized reporting format, which facilitates cross-national comparisons. The analysis shows that impacts and adaptation receive limited attention within NCs. The discussion on impacts and adaptation has typically been dominated by climate scenarios and impacts analysis, while the discussion on adaptation is often limited to the identification of generic options. There are signs of recent progress, however, in the Third and especially the Fourth NCs, in which a growing number of developed countries report on establishing frameworks for adaptation and on efforts to implement adaptation measures that take future climate into account. Although an encouraging sign, it is still too early to assess the eventual impact of such measures. 相似文献
85.
《The Professional geographer》1982,34(4):458-490
Books reviewed in this article: Aerial Photography and Remote Sensing. Terrain Analysis and Remote Sensing . JOHN R. G. TOWNSHEND , ed. Environmental Data Use in Computer-assisted Data Handling Systems: The Results of a Survey of Applications in the Pacific Northwest States . KENNETH E. GORDON . Applied Land Use: A Spatial Approach . JOHN F. LOUNSBURY , LAWRENCE M. SOMMERS , AND EDWARD A. FERNALD , eds. The Second Battle of New Orleans: A History of the Vieux Carre Riverfront-Expressway Controversy . RICHARD O. BAUMBACH , JR. AND WILLIAM E. BORAH . Cultural Environmental Archaeology . MYRA SHACKLEY . The Immoral landscape: Female Prostitution in Western Societies . RICHARD SYMANSKI . life Among the Poor in Cairo . UNNI WIKAN , translated by Ann Henning. Women, Work and Property in Northwest India . URSULA SHARMA . The Domestication of Women: Discrimination in Developing Societies . BARBARA ROGERS Economic Optimization in Locational and Transport Analysis . A. G. WILSON , J. D. COELHO , S. M. MACGILL , H. C. W. L. WILLIAMS . New Tools for Economic Development: The Enterprise Zone, Development Bank, and RFC . GEORGE STERNLIEB AND DAVID LISTOKIN , eds. Regional Wage Inflation . R. L. MARTIN , ed. Finding A Place For Energy-Siting Coal Conversion Facilities . FRANK J. CALZONETTI WITH MARK S. ECKERT . Environmental Management, Resources, and Systems Environmentalism. Second Edition . T. O'RIORDAN . Countryside Conservation . BRYN GREEN . Medical Spatial Diffusion: An Historical Geography of Epidemics in an Island Community . A. D. CLIFF , P. HAGGETT , J. K. ORD , AND G. R. VERSEY . Philosophy and Geographic Thought Order and Skepticism: Human Geography and the Dialectic of Science . RICHARD SZYMANSKI AND JOHN A. AGNEW . Measurement of Subjective Phenomena . D. F. JOHNSTON , ed. Conceptions of Space in Social Thought: A Geographic Perspective . ROBERT DAVID SACK . The Association of American Geographers: The First Seventy-five Years: 1904-1979 . PRESTON E. JAMES AND GEOFFREY J. MARTIN . The Life and Thought of Isaiah Bowman . GEOFFREY J. MARTIN . Physical River Basin Planning: Theory and Practice . SURANJIT K. SAHA AND CHRISTOPHER J. BARROW , eds. Soils and landforms: An Integration of Ceomorphology and Pedology . A. I. GERRARD Climatic Change and Society. Consequences of Increasing Atmospheric Carbon Dioxide . WILLIAM W. KELLOGG AND ROBERT SCHWARE . Political Political Redistrictings and Geographic Theory . RICHARD L. MORRILL . Population Studies in Spanish American Population History: Dell Plain Latin American Studies NO. 8 . DAVID J. ROBINSON , ed. Population Redistribution in the Midwest . CURTIS C. ROSEMAN , ANDREW J. SOFRANKO , AND JAMES D. WILLIAMS , eds. Geographical Perspectives on the Elderly . A. M. WARNES , ed. Regional Perspective On the American South . MERLE BLACK AND JOHN SHELTON REED , eds. The Prairies and Plains: Prospects for the 80s . JOHN R. ROGGE , ed. Rural Rural Settlement in an Urban World . MICHAEL BUNCE . Social Accident at Three Mile Island: The Human Dimensions . DAVID L. SILLS , C. P. WOLF , AND VIVIEN B. SHELANSKI , eds. The American Small Town: Twentieth-Century Place Images . JOHN JAKLE . Urban A House of My Own . SUSAN LOBO . The City: Patterns and Processes in the Urban Ecosystem . CHRISTOPHER H. EXLINE , GARY L. PETERS , AND ROBERT P. LARKIN . Movement in Cities . P. W. DANIELS AND A. M. WARNES . Urbanization and Urban Planning in Capitalist Society . MICHAEL DEAR AND ALLEN J. SCOT , eds. 相似文献
86.
多比例尺空间数据的表达与处理是GIS的一个固有问题,本文用土地信息多级网格代替多级土地数据库中的多比例尺数据库及其多比例尺表达,以解决多级土地数据库建库过程中制图综合带来的地类数据变化问题,同时也为土地数据的共享提供了方便. 相似文献
87.
The Tornado Hazard In Southern New England: History,Characteristics, Student And Teacher Perceptions
《The Journal of geography》2012,111(6):258-266
Abstract People generally do not perceive New England to be tornado-prone. Yet, there is a long history of such storms in the six states going back to the late seventeenth century. Usually, New England tornadoes are small and short-lived; even so, some have caused many deaths and much property damage. There is a greater probability for a person to be affected by a tornado in southern New England than in much of the American Midwest. As building and population density increases, so does the hazard potential. Data from awareness surveys indicate that the lack of tornado knowledge remains a serious problem for teachers, students, and the public, and government information about such storms is not being widely disseminated. 相似文献
88.
《The Journal of geography》2012,111(3):105-112
Abstract Geography teacher preparation is an ongoing problem for the discipline. Changes in certification requirements and federal and state educational policies have diminished the role of colleges and universities in educating teachers. At the same time, geography education reform efforts have resulted in higher standards and an increased quantity of geography in the curriculum, pre-service programs have failed to produce an adequate supply of highly qualified geography teachers. This paper suggests that geographers implement geography mentoring programs to improve the quality of geography instruction in early-career teachers. A model developed for the National Geographic Society is described. The model uses Teacher Consultants as mentors to assist novice teachers at the stage in their development when they are most ready to improve practice: between years two and five of their career. 相似文献
89.
2008~2010年,在鱼类资源调查的基础上,分析了莫莫格国家级自然保护区的鱼类多样性特征。调查结果显示,莫莫格国家级自然保护区有鱼类物种5目11科42属49种,其中本区土著种5目10科38属45种,包括中国特有种4种,中国易危种5种,冷水种8种,国家II级保护动物1种。土著种群落中,有鲤形目(Cyprini-formes)鱼类32种,鲤科(Cyprinidae)鱼类29种,鮈亚科(Gobioninae)鱼类13种;古北界北方区黑龙江亚区黑龙江分区的物种为22种;源于东部平原和北方平原生态类群的鱼类有27种;适应于江—湖缓流环境和淡水定居生活的鱼类有33种;草上产卵和水层产卵繁殖的鱼类有37种;杂食性和初级肉食性种类有28种,它们均相对占优势。莫莫格国家级自然保护区与嫩江的鱼类群落物种结构Jaccard系数和Morisita-Horn相似性指数分别为0.918和0.838;稀有种(包括中国易危种)和常见种分别为14种和25种;物种多度格局近似于对数正态分布。这些结果表明,莫莫格国家级自然保护区的鱼类多样性与嫩江密切相关,鱼类区系复杂,物种组成与生态类型多样;群落结构相对较稳定,多样性程度相对较高,但仍面临着稀有种(包括中国易危种)尚占有一定比例而导致群落结构脆弱的潜在威胁。保持嫩江鱼类群落结构的稳定,对维护和发展莫莫格国家级自然保护区的鱼类多样性具有特别重要的意义。 相似文献
90.