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271.
Resource use efficiency analyses of village ecosystem are necessary for effective and efficient planning of resource utilization. This paper deals with economic and energy input-output analyses of different components of village ecosystem in representative buffer zone villages, which are practicing transhumance and settled way of lifestyles in Nanda Devi Biosphere Reserve (NDBR) of Garhwal Himalaya. While the villages practicing transhumance used various natural resources spatially segregated,the villages practicing settled way of lifestyle have to manage resources from a limited spatial area through rotation and varied extraction intensities. Forests subsidized the production activity in both type of villages and the per capita resource extractions were found to be greater in tran~humance village than settled village. Though crops provided maximum energy, in terms of economic criteria, animal husbandry played important role in both settled and transhumance villages. As villages representing both the situations showed different ways of adjustments to the conservation oriented land use changes, management authority needs to address the eco-development plans fulfilling the aspirations of all people traditionally using the resources of the Reserve to reduce the conflicts and encourage their participation in the conservation of the area.  相似文献   
272.
BOOK REVIEWS     
Books reviewed in this article: Aerial Photography and Remote Sensing Aerial photography and image interpretation for Resource Management . DAVID P. PAINE . Analytical Models and Techniques Spatial Processes Models and Applications A. D. CLIFF AND J. K. ORD Quantitative and Statistical Approaches to Geography: A Practical Manual JOHN A. MATTHEWS . Cartography and Maps Map Data Processing . HERBERT FREEMAN AND GOFFREDO G. PIERONI , eds. Computer-assisted Cartography: Principles and Prospects, 1982 . MARK S. MONMONIER . Cultural Navajo Architecture: Forms, History, Distributions . STEPHEN C. JETT AND VIRGINIA E . SPENCER . Rational Landscapes and Humanistic Geography . EDWARD RELPH . Economic The Structure and Control of a State Economy . W. L. L'ESPERANCE . Economic Geography . JAMES O. WHEELER AND PETER O. MULLER . The Myth of the Family Farm: Agribusiness Dominance of U.S. Agriculture . INGOLF VOCELER . Libya: The Experience of Oil . J. A. ALLEN . Geography of Public Finance, Welfare Under Fiscal Federalism and local Government Finance . ROBERT BENNETT . Environmental Management, Resources, and Systems Mountains and Man . LARRY W. PRICE . Environmental Geology . DONALD R. COATES . An Introduction to Environmental Systems . G. H. DURY . The Environment: Chinese and American Views . Edited by LAURENCE J. C. MA AND ALLEN G. NOBLE . Land Use in America . RICHARD H. JACKSON . Medical Conceptual and Methodological Issues in Medical Geography . MELINDA S. MEADE (ed.). Philosophy and Geographic Thought Birds in Egg/Eggs in Bird . GUNNAR OLSSON . PhysicaI Climatology: Selected Applications . J. E. OLIVER . Geomorphological Techniques . ANDREW GOUDIE (ed.). Political Politics, Geography and Behaviour . RICHARD MUIR AND RONAN PADDISON . The State of the World Atlas . MICHAEL KIDRON AND RONALD SECAL . Population The Population of the South . DUDLEY L. POSTON , JR . AND ROBERT H. WELLER , eds. Regional Latin America: Economic Development and Regional Differentiation . ARTHUR MORRIS . Developing the Amazon . EMILIO F. MORAN . Western Europe: A Systematic Human Geography . BRIAN W. ILBERY . Settlement Systems in Sparsely Settled Regions: The United States and Australia . RICHARD E. LONSDALEAND JOHN H. HOLMES , eds. African Perspectives: The Economic Geography of Nine African States . HARM DE BUJ AND ESMOND MARTIN , eds. Rural Nonmetropolitan America in Transition . AMOS H. HAWLEY AND SARA MILLS MAZIE , eds. Social Crime and Environment . R. NORMAN DAVIDSON . The Ghetto: Readings with Interpretations . JOE T. DARDEN , ed. Urban Urban Problems and Planning in the Developed World . MICHAEL PACIONE (ed.) Problems and Planning in Third World Cities . Edited by MICHAEL PACIONE . The City in West Europe . D. BURTENSHAW , M. BATEMAN , AND C. J. ASHWORTH .  相似文献   
273.
Over the past two decades development has been shifting its focus toward smaller scales and particular problems. As a result, the household has become an increasingly important institution for development, and has come under increased scrunity as development practitioners and scholars seek to better understand this institution’s functions and foundations, trying to ‘get the household right’. These efforts, rather than clarifying the character and the function of the household, have contributed to its indeterminacy by reifying the very institution they seek to analyse. Arguing that these efforts fundamentally miss the point of examining the household, this paper introduces a different framework of analysis that addresses the household not as a fixed object of research, but as a local construction that embodies flows of power and knowledge both within and transcending the local. Using the example of varying constructions of the household in two villages in Ghana’s Central Region, this article illustrates how such an approach allows us to address the various functions of the household as particular embodiments of these flows, an approach that better explains the endurance or ephemerality of these functions. Such an approach provides a stronger foundation for the consideration of how particular constructions of this institution may have troubling implications for issues like gender equity and sustainability.  相似文献   
274.
A pilot study of spatial patterns of agricultural drought hazard in the south-central Pacific is presented. The durations of crop stress periods are estimated using a water balance approach. A rainfall approach is used to identify dry periods corresponding to different durations. Strong correlation between the results of the two methods indicates that monthly rainfall data are sufficient for estimating the patterns of agricultural drought hazard in the region. The simpler rainfall method is particularly useful for high islands where data required for the water balance approach are not sufficient to characterize the complex climatic patterns. Drought hazard is greatest in the eastern and southwestern parts of the study area. Great spatial variation in drought hazard is observed in a small area on the high islands of Western Samoa, where the range of values found within a few tens of kilometers is about the same as the range found across thousands of kilometers for low islands.  相似文献   
275.
中国区域土地利用/覆被变化对陆地碳收支的影响   总被引:2,自引:0,他引:2  
准确估计土地利用/覆被变化(LUCC)对陆地生态系统碳收支的影响已成为当前全球变化和全球碳循环研究的重点内容。本文通过文献调研和数据的整合分析方法总结讨论了近年来中国区域LUCC时空特征及其对陆地碳收支影响,为合理评价中国区域陆地碳平衡以及确定未来研究发展方向提供参考。已有大量研究对近年来中国区域LUCC主要特征进行了探讨,并分别利用卫星遥感方法和IPCC清单法对中国区域陆地碳源汇影响进行了评估。结果表明,目前全国土地利用活动,特别是农林活动正对陆地生态系统碳收支产生了比较显著的积极作用,但基于以上两种方法的研究结论之间差异很大,反映出中国LUCC导致陆地碳收支变化的评估结果仍存在着较大的不确定性。通过分析认为,中国未来的研究工作应着重于发展和利用基于土地利用相互转化面积的计量方法,以提高对中国区域LUCC导致陆地碳收支变化评估的准确性。  相似文献   
276.
澜沧江流域农业灌溉需水的时空变化(英文)   总被引:1,自引:0,他引:1  
Based on the data of eight meteorological stations from the 1950s to 2007, current cropping patterns, field water moisture management, we use the Mann-Kendall and the Re-scaled Range Analysis methods to research the changes of humidity and crop irrigation water requirements in the Lancang River Basin. The results show that the annual and dry season average temperatures significantly increased, and the dry season rainfall increased while wet season rainfall decreased. Evaportranspiration (ET0) increased during both dry and wet seasons at all stations except Dali, Jianchuan and Gengma, and the aridity-humidity index decreased at most of the stations. The turning points of weather factors, ET0, the arid-ity-humidity index, paddy irrigation requirements and total agricultural water requirements occurred from the 1960s to the 1990s. The spatial changing tendency of paddy irrigation quota increased with the increase of altitude and latitude, and the correlation coefficients are 0.513 and 0.610, respectively. The maximum value is observed in Weixi, while the minimum in Mengla.  相似文献   
277.
甘肃敦煌西湖荒漠湿地植物群落物种多样性特征研究   总被引:5,自引:1,他引:4  
 基于375个样方和150条样线的调查,对甘肃敦煌西湖荒漠-湿地生态系统植物群落物种多样性进行了研究。结果表明:①区内共记录植物26种,分属16科24属,芦苇(Phragmites australis)、多枝柽柳(Tamarix ramosissima)和胡杨(Populus euphratica)为绝对优势种,苏枸杞(Lycium ruthenicum)、疏叶骆驼刺(Alhagi sparsifolia)和胀果甘草(Glycyrrhiza inflata)为主要伴生种,其平均重要值依次为0.4728、0.4563、0.4342、0.2908、0.2594和0.2455。植物群落分多枝柽柳群落、胡杨群落、胀果甘草群落、疏叶骆驼刺群落、多枝柽柳沙包群落、苏枸杞群落、芦苇沼泽群落和芦苇群落8个类型。②植物群落物种多样性指数偏低(0.784~1.379),多枝柽柳群落、胡杨群落和芦苇群落物种多样性指数最大(1.379、1.266和1.194),群落之间差异显著(P<0.05);疏叶骆驼刺群落和苏枸杞群落次之(1.154、1.077),胀果甘草群落、芦苇沼泽和多枝柽柳沙包群落最低(0.919、0.881、0.784),各群落之间不存在显著差异。③灌(乔)木层是敦煌西湖植被主要层次,灌(乔)木层物种多样性指数(0.549~1.077)大于草本层(0.052~1.038)。④物种多样性指标H′、D、J和Ma随海拔梯度增加基本均显下降趋势,而指数C变化趋势则相反,表现为上升,均匀度指数变化幅度不显著。⑤物种多样性指标H′、D、J和Ma随经纬度升高变化趋势基本一致,均表现为先下降,后上升,再下降,而优势度指数C变化趋势则相反。  相似文献   
278.
葛小东  黄超  叶青 《中国沙漠》2012,32(5):1457-1462
 基于数据包络分析方法对通辽市各旗县2000—2008年农业生产技术效率进行综合评价。结果表明:①通辽市农业生产技术效率整体上较低,但呈逐年上升的趋势。②通辽市各旗县农业生产技术效率的时空差异明显,霍林郭勒和开鲁县的农业生产技术效率表现为先降低后上升;库伦旗和科尔沁左翼中旗农业生产技术效率表现为持续上升;科尔沁左翼后旗、扎鲁特旗和奈曼旗的农业生产技术效率表现为随时间呈现一定波动性;各旗县中奈曼旗年均效率最高。③通辽市农业生产技术效率主要受投入冗余影响,各旗县均存在降水冗余,反映出当地农业生产投入的盲目性。降水的波动性和不确定性导致灌溉用水、耕地面积投入过多,进而影响了各旗县农业生产技术效率。不同旗县在不同年份的投入冗余有所差异,显示农民应对降水变动的措施也具有一定盲目性。建议针对气候的不确定性对农业生产的干扰展开研究,改进农业生产技术。  相似文献   
279.
青海省海东地区土地利用变化及其生态服务价值响应   总被引:2,自引:0,他引:2  
根据青海省海东地区2002~2008年土地利用变更数据,采用土地利用动态度模型和土地利用综合指数分析该地区近7年来土地利用变化情况,并参考谢高地等人建立的中国陆地生态系统单位面积生态服务价值当量表对该区域当量表进行适当调整,测算了土地利用变化所引起的生态服务价值变化情况。研究表明:(1)2002~2008年,各类型土地利用变化速度各不相同,其中以水利设施用地变化速度最快为12.24%,土地利用程度波动上升;(2)土地利用变化所引起的生态服务价值总体上呈逐步上升趋势,由2002年的82.01×10^8元增加至2008年的88.16×10^8元,增加了6.15×10^8元;(3)各种土地利用类型的生态系统服务价值的敏感性指数均小于1,表明生态系统服务价值对价值系数的变化缺乏弹性,研究结果可信。  相似文献   
280.
李冰  毕军  田颖 《地理科学》2012,(4):471-476
通过对太湖流域重污染区1999年、2007年遥感影像数据解译结果的分析,获取了太湖流域重污染区主要土地利用类型的信息,分析了8 a来研究区内土地利用与覆被变化趋势,对区域土地利用类型的生态系统服务价值进行评估。结果表明,1999~2007年,太湖流域重污染区内耕地面积从2 033.53 km2减少到1 401.04 km2,而林地、建设用地、园地、水域总体呈增加的趋势,其中减少的耕地主要转化为建设用地。1999~2007年太湖流域重污染区的生态系统服务价值呈减少趋势,土地利用变化使研究区生态资产减少了2.40亿元,除气体调节和原材料以外,各单项服务功能的价值量均呈现递减的趋势。  相似文献   
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