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101.
ANANALYSISOFWATERRESOURCECHARACTERISTICSOFTHERIVERSINTHENORTHERNSLOPEOFTHEKUNLUNMOUNTAINSXuYoupeng(许有鹏);GaoYunjue(高蕴珏)(Depart...  相似文献   
102.
BOOK REVIEWS     
Book Reviewed in this article: Marine Resources of Kuwait: Their Role in the Development of Non-oil Resources . Fatimah H. Y. al -Abdul -Razzak Recollections of a Revolution: Geography as Spatial Science . Mark Billinge , Derek Gregory and Ron Martin Entre l'Eden et l'Utopie . Luc Bureau Developments in Political Geography . M. A. Busteed The Elements of Graphing Data . William S. Cleveland Rural Resource Management . Paul J. Cloke and Chris C. Park Third World Atlas . Ben Crow and Alan Thomas Exploitation, Conservation, Preservation: A Geographic Perspective on Natural Resource Use . Susan L. Cutter , Hilary Lambert Renwick, and William H. Renwick . Wine Regions of the Southern Hemisphere . Harm Jan de Blij Regional Development: Problems and Policies in Eastern and Western Europe . George Demko The Geographer at Work . Peter R. Gould Change in the Amazon Basin . John Hemming Geography Since the Second World War . R. J. Johnston and P. Claval Urbanization in China: Town and Countryside in a Developing Economy 1949–2000 A.D. , R. J. R. Kirkby Transport and Communications for Pacific Microstates: Issues in Organisation and Management . Christopher C. Kissling Fluvial Forms and Processes . David Knighton The Urban Millennium . Josef W. Konvitz Technological Transition in Cartography . Mark Stephen Monmonier Field Guide to Soils and the Environment: Applications of Soil Surveys . Gerald W. Olson Northern Australia: The Arenas of Life and Ecosystems on Half a Continent . Don Parkes A Killing Rain: The Global Threat of Acid Rain . Thomas Pawlick From the Family Farm to Agribusiness: The Irrigation Crusade in California and the West, 1850–1931 . Donald J. Pisani Hybrid Maize Diffusion in Kenya . Franz -Michael Rundquist Warning and Response to the Mount St. Helens Eruption . Thomas F. Saarinen and James L. Sell Coastal Geomorphology in Australia . B. G. Thom Tropical Rain Forests of the Far East , 2nd ed . T. C. Whitmore The Dark Side of the Earth . Robert Muir Wood Categorical Data Analysis for Geographers and Environmental Scientists , Neil Wrigley  相似文献   
103.
国际海洋新秩序及其对我国海洋经济的影响   总被引:1,自引:0,他引:1  
国际海洋新秩序的形成以<联合国海洋法公约>的生效为标志.<公约>不仅赋予了沿海国对200 n mile专属经济区的主权权利等海洋权益,带来国际海洋形势的新趋势,而且会对我国海洋经济产生重要影响.<公约>的生效一方面促进了我国海洋法律的建设进程,扩大了海洋管辖;另一方面又使我国海洋经济权益受到新的威胁.专属经济区制度对我国海洋渔业生产和管理也将产生重要影响.  相似文献   
104.
Abstract

How beginning teachers organize themselves to teach new or unfamiliar topics is an important issue for research. This paper discusses information about rivers in pre-service teachers' lessons taught to fourth grade students. Lessons were videotaped and transcribed for analysis. The data consisted of all information about rivers found in the lessons. Lesson content was analyzed for accuracy, coherence, centrality, over-simplification, and undue emphasis.

Seven kinds of problems with lesson content occurred because the beginning teachers lacked sufficient knowledge about rivers. Inaccurate information was either presented or allowed to stand unchallenged in the lessons. The lessons lacked coherence, because the beginning teachers tended to make passing references to concepts. About twice as many of the lesson concepts were peripheral to the study of rivers, the problem of centrality. The relationships between some river-related ideas were misunderstood or ignored. Both physical and human geography concepts were consistently over-simplified. The recreational use of rivers was consistently over-emphasized.  相似文献   
105.
南海问题的大周边地缘环境   总被引:6,自引:1,他引:5  
南海的西沙、南沙等历来是中国的领土,但如今海洋国土存在重大争议,南海已经成为世界上最复杂、最紧张的水域之一,南海周边的政治、军事、经济地缘环境也越来越为复杂。本文以南海问题为切入点,基于南海地理区位中的要素联系对南海周边国家的地缘环境进行探讨。结果得出:南海问题是涉及多元利益和跨国机构关联的复杂问题,南海周边是一个包含域内争端国家、域外干涉国家和具有复杂组织机构关联的"大"周边,南海周边地缘环境是超出地理毗邻的"大"地缘环境,中国南海的维权维稳势必要在域内双边地缘环境、域外多边地缘环境、国际多元多边地缘环境等构成的大周边地缘环境下做出战略决策。  相似文献   
106.
章锦河  刘珍珍  陈静  周晶  李曼 《地理科学》2012,(10):1161-1167
出境旅游是国际服务贸易的重要组成部分,是世界经济全球化的响应。出境旅游与国际服务贸易关系分析是制定出境旅游政策的基础之一。根据1985~2011年中国出境旅游和国际服务贸易时间序列的相关数据,采用计量经济学分析方法,系统探讨了出境旅游与国际服务贸易的关系。得出结论:①出境旅游与国际服务贸易之间存在正相关关系;②出境旅游与国际服务贸易存在长期稳定的动态均衡关系;③出境旅游与国际服务贸易存在短期波动回归长期均衡关系;④出境旅游是国际服务贸易出口的Granger原因,但不是国际服务贸易进口的Granger原因,国际服务贸易进出口均是出境旅游的Granger原因。  相似文献   
107.
三江源地区草地退化对中国区域气候影响的数值模拟研究   总被引:8,自引:2,他引:6  
廉丽姝  束炯  李朝颐 《气象学报》2009,67(4):580-590
人类活动导致的土地利用变化是区域气候变化的一个重要驱动因素.位于青藏高原腹地的三江源地区,生态系统十分脆弱,其独特的地理位置决定了源区的生态环境对中国乃至全球的气候变化、生态环境均有十分重要的影响.该研究应用区域气候模式RegCM3,通过两组数值模拟试验结果的对比分析,探讨三江源地区的草地退化对中国区域气候的影响.模拟试验的区域模式水平分辨率为60 km,模拟区域中心位于35°N,105°E,水平格点数为92×82,相当于5520 km×4920 km的范围.研究结果表明:RegCM3对中国区域气候具有较好的模拟能力,能够用于定量研究土地利用变化对区域气候的影响.三江源地区的草地退化引起的气候变化在不同的地区是不一致的,变化最明显的地区是青藏高原地区.草地退化将会引起青藏高原地区的冬季降温和其他季节升温,气温变化最显著的季节是春季(0.46℃),冬季变化最小(0.03℃);三江源地区的草地退化对中国中、东部地区的气候影响较复杂,主要表现为夏季长江以北地区有不同程度的升、降温现象.由于青藏高原夏季热源作用的加强,导致夏季青藏高原低层大气的热低压有所加强,太平洋副热带高压向东退缩.降水量的变化主要表现在夏季降水的普遍减少.草地退化后,青藏高原地区的气候有向暖于方向发展的趋势.  相似文献   
108.
应对气候变化的国际技术协议评述   总被引:1,自引:1,他引:0  
 国际技术协议通过促进技术的转让与升级,在发展中解决气候变化问题,因此受到越来越多的关注。根据"巴厘路线图"中的重要议题,在对国际技术协议进行简要介绍的基础上,评价了国际技术协议内在的价值与局限性。最后对国际技术协议的前景进行了展望,指出国际技术协议应当着眼于通过促进环境友好的先进技术由发达国家向发展中国家的转让,推动在应对气候变化领域内更深层次的南北合作,实现发展中国家的可持续发展,逐步解决气候变化问题。同时,为中国如何参与国际技术协议给出了建议。  相似文献   
109.
The sources and fluxes of sediment to the Great Barrier Reef lagoon from north‐eastern Australian rivers have been the subject of much concern and study, with the large catchments of the Burdekin and Fitzroy Rivers thought to be the key sources at present. Here, the utility of newly developed magnetic ‘fingerprinting’ methods for identifying sediment provenance, both onshore and offshore, and in association with individual large flood events, is investigated. Within the Burdekin catchment, sediments are mobilized from different subcatchments by runoff generated by intense, localized rainfall events. Magnetic measurements were made on untreated and acid‐treated samples of river channel sediments within the Burdekin River subcatchments and from the estuarine and inner shelf depocentres of Burdekin River sediments. The acid treatment removes all discrete magnetic particles and coatings, and leaves magnetic inclusions (protected within host silicate grains) as the basis of the measured magnetic signature of a sample. The magnetic properties of the acid‐treated samples display statistically distinct sediment provenance groupings. Sand samples from the Upper Burdekin River appear magnetically distinct from samples from tributaries of the Burdekin (e.g. Hann Creek, Fanning River) and also from nearby coastal rivers, including the Haughton. Suspended sand samples from a Burdekin flood event in 2000 appear to have a different source compared with those from floods in 1998 and 1999. Comparisons of the terrestrial, acid‐treated sand fractions with the same, acid‐treated, sand‐size fractions from transects taken offshore suggest that the surface sediments in Upstart Bay and Bowling Green Bay have different sources. Some of these sources are as yet unidentified but may represent the unsampled, lower‐discharge south‐western Burdekin subcatchments, and/or along‐shore drift of sand from the south, perhaps even from the Fitzroy River, over millennial timescales of cyclone pumping. The magnetic inclusion method precludes any obfuscation or confounding of sediment source, which might arise from hydraulic sorting and/or post‐depositional magnetic diagenesis or authigenesis.  相似文献   
110.
Assumptions about fluvial processes and process–form relations are made in general models and in many site-specific applications. Many standard assumptions about reach-scale flow resistance, bed-material entrainment thresholds and transport rates, and downstream hydraulic geometry involve one or other of two types of scale invariance: a parameter (e.g. critical Shields number) has the same value in all rivers, or doubling one variable causes a fixed proportional change in another variable in all circumstances (e.g. power-law hydraulic geometry). However, rivers vary greatly in size, gradient, and bed material, and many geomorphologists regard particular types of river as distinctive. This review examines the tension between universal scaling assumptions and perceived distinctions between different types of river. It identifies limits to scale invariance and departures from simple scaling, and illustrates them using large data sets spanning a wide range of conditions. Scaling considerations and data analysis support the commonly made distinction between coarse-bed and fine-bed reaches, whose different transport regimes can be traced to the different settling-velocity scalings for coarse and fine grains. They also help identify two end-member sub-types: steep shallow coarse-bed ‘torrents’ with distinctive flow-resistance scaling and increased entrainment threshold, and very large, low-gradient ‘mega rivers’ with predominantly suspended load, subdued secondary circulation, and extensive backwater conditions. © 2020 The Authors. Earth Surface Processes and Landforms published by John Wiley & Sons Ltd  相似文献   
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