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991.
正2014年7月6日,中国科学院科技促进发展局组织验收专家组,对新疆生态与地理研究所承担的中国科学院西部行动计划(三期)项目"援疆政策环境下新疆跨越式发展战略研究"和"新疆油田作业废液无害化和资源化处理技术体系研究与示范"进行了验收。"援疆政策环境下新疆跨越式发展战略研究"的开展,旨在从全局角度统筹新疆的跨越式发展的战略部署,规划援疆行动,分析新形势下新疆跨越式发展的目标、战略重点、发展途径和政策措施,并针对援疆行动可能存在的重复建设、无效援建、生态环境继续恶化等问题提出解决方案。项目组通过该项目的实施,构建了援疆行动与新疆县域发展动态监测与分析平台,可动态监测与发  相似文献   
992.
以新疆干旱区绿洲城市为研究对象,对2005-2008、2011年TSP和PM10监测指标数据进行相关性分析,对比研究TSP与PM10监测指标对应的API污染指数分布和空气质量等级。结果显示:这两种大气颗粒物指标对新疆干旱区城市环境空气质量级别的影响显著,在春季沙尘多发期和冬季采暖期,以TSP标准评估的API空气质量等级与PM10为评价标准的空气质量结果偏离明显;监测指标采用PM10代替TSP后,城市环境空气质量出现较大幅度提升,环境空气质量优良率偏高,年均污染天数减少约50~60 d,以PM10作为空气质量监测指标的空气质量级别严重偏低,无法真实评价干旱区城市的空气质量现状,而TSP作为评价指标则更能如实反映当地空气质量的真实状况,建议在新疆城市在开展PM10监测的同时不应简单废弃TSP监测指标,TSP监测指标在干旱区环境空气质量监测体系中应该继续保留,同时建议在今后环境空气质量标准修订中适当收严PM10的日均值标准,使评价结果与TSP和PM10两指标评价结果不至于相差悬殊。  相似文献   
993.
正森林土壤是陆地生态系统土壤中最大的碳库,约占全球土壤碳库的3/4,在全球C循环中起至关重要作用[1]。土壤异养呼吸(Heterotrophic respiration,Rh)是森林生态系统土壤碳库损失的主要途径。土壤异养呼吸是指土壤在微生物参与下的矿化过程,主要包括根际微生物呼吸、矿质土壤呼吸(无根土壤)和枯枝落叶层呼吸,由于土壤动物呼吸量不大,因此森林生态系统的异养呼吸主要表现为矿质土壤呼吸[2-4]。土壤异养呼吸具有高度的空间变异性,在全球范围内,异养呼吸所占总呼吸的比例为7%~83%,其中在热带和温带(30%~83%)森林生态系统中所占比例高于寒带地区(7%~  相似文献   
994.
Land cover change affects surface radiation budget and energy balance by chang- ing surface albedo and further impacts the regional and global climate. In this article, high spatial and temporal resolution satellite products were used to analyze the driving mechanism for surface albedo change caused by land cover change during 1990-2010. In addition, the annual-scale radiative forcing caused by surface albedo changes in China's 50 ecological regions were calculated to reveal the biophysical mechanisms of land cover change affecting climate change at regional scale. Our results showed that the national land cover changes were mainly caused by land reclamation, grassland desertification and urbanization in past 20 years, which were almost induced by anthropogenic activities. Grassland and forest area decreased by 0.60% and 0.11%, respectively. The area of urban and farmland increased by 0.60% and 0.19%, respectively. The mean radiative forcing caused by land cover changes during 1990-2010 was 0.062 W/m2 in China, indicating a warming climate effect. However, spatial heterogeneity of radiative forcing was huge among different ecological regions. Farmland conversing to urban construction land, the main type of land cover change for the urban and suburban agricultural ecological region in Beijing-Tianjin-Tangshan region, caused an albedo reduction by 0.00456 and a maximum positive radiative forcing of 0.863 WIm2, which was presented as warming climate effects. Grassland and forest conversing to farmland, the main type of land cover change for the temperate humid agricultural and wetland ecological region in Sanjiang Plain, caused an albedo increase by 0.00152 and a maximum negative radiative forcing of 0.184 W/m2, implying cooling climate effects.  相似文献   
995.
<正>近日在京召开的2014年全国地质调查工作会议提出,今后一个时期,地质调查工作重点要进行调整,在紧紧围绕"358"目标加强矿产调查的同时,基础地质调查向森林、沼泽、湿地、海岛、海岸带等特殊地质地貌区拓展,同时调查内容更加综合,方式更加先进。会议提出,今后一个时期,地质调查工作要紧紧围绕找矿突破战略行动"358"目标,坚持找矿新机制,评估3年地质调查的服务支撑完成情况,总结经验,分析问题,及时调整地质调查实施方案,全力助推"358"第二阶段目标实现。资源调查要从点上评价走向面上调查,突出整装勘查  相似文献   
996.
<正>2014年一季度呼和浩特市地价动态监测面积仍保持为210.01平方公里,共布设标准宗地201个。一季度呼和浩特市地价总体水平为3,042元/平方米,环比增长2.29%,与上一季度相比,下降了1.73%;商业用地地价总体水平为4,283元/平方米,环比增长1.88%,与上一季度相比,下降了2.83%;住宅用地地价总体水平为3,365元/平方米,环比增长2.25%,与上一季度相比,  相似文献   
997.
县级耕地质量等别时空变化特征   总被引:1,自引:0,他引:1  
掌握区域耕地质量时空变化特征,对于科学制定基本农田保护、土地整治、耕地质量监测对策具有重要意义。本文选取位于农牧交错带的内蒙古达拉特旗为研究案例,根据2000年、2007年、2010年、2011年达拉特旗土地利用现状数据,同时依据国土资源部农用地分等和内蒙古上轮分等技术参数,分析了达拉特旗耕地质量等别时空变化分布特征。研究结果表明,该地区四个时期的耕地质量结果发生了显著变化,总体上耕地质量呈现增加趋势,且北部平原区尤为明显,南部丘陵区变化不大。这种耕地质量的变化与近年来开展的大规模农业结构调整和土地综合整治等工程密切相关。根据耕地等别时空变化特征,可以对研究区内的耕地等别演化方向进行预测,以期为制定区域耕地保护和土地整治对策提供科学依据。  相似文献   
998.
The normalized difference vegetation index (NDVI) is used extensively to describe vegetation cover and ecological environ- ment change. The purpose of this study was to contrast the response of different tree species growing in the same habitat to climate change and retrieve past NDVI using tree-ring width data from tree cores collected from the transitional zone of Pinus tabulaeformis and Picea crassifolia in the Luoshan Mountains in the middle arid region of Ningxia. Correlation analysis indi- cated that radial growth ofP tabulaeJbrmis is more sensitive to precipitation and temperature change than that ofP crassifolia. Natural factors such as water availability and heat at this elevation are more suited to the growth ofP crassifolia, and are more advantageous to its renewal and succession. P. crassifolia is probably the better of the two species for protecting the forest ecosystem and conserving water in the Luoshan desertification area. Ring width of P. crassifolia correlates significantly with average NDVI for April-May (r =0.641, p 〈0.01), and both of them are influenced positively by precipitation in April-May. The reconstructed NDVI for 1923-2007 shows the relatively low vegetation cover occurred in the 1920s-1930s, the 1960s-1970s, and the early 21 st century. The reconstructed NDVI better reflected the drought climate in the study area.  相似文献   
999.
Because of similar reflective characteristics of snow and cloud, the weather status seriously affects snow monitoring using optical remote sensing data. Cloud amount analysis during 2010 to 2011 snow seasons shows that cloud cover is the major limitation for snow cover monitoring using MOD10A1 and MYD10A1. By use of MODIS daily snow cover products and AMSR-E snow wa- ter equivalent products (SWE), several cloud elimination methods were integrated to produce a new daily cloud flee snow cover product, and information of snow depth from 85 climate stations in Tibetan Plateau area (TP) were used to validate the accuracy of the new composite snow cover product. The results indicate that snow classification accuracy of the new daily snow cover product reaches 91.7% when snow depth is over 3 cm. This suggests that the new daily snow cover mapping algorithm is suitable for monitoring snow cover dynamic changes in TP.  相似文献   
1000.
Global climate warming which began in the second half of the twentieth century is continuing. It is associated with increased risks for ecological management, especially in permafrost areas comprising over 65% of Russia. Of special concern are dams constructed on permafrost. They are subject not only to climatic impacts, but also to additional hydrothermal loads from water reservoirs. This paper presents the concept of geocryological monitoring of dams and other water resource projects and substantiates its necessity in view of climatic change. It also presents methods, scope and implementation of geocryological monitoring at medium and small dams, considering the specific nature of Far Northern areas, as well as the complicated geotechnical, hydrogeological and permafrost conditions.  相似文献   
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