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361.
《Climate Policy》2013,13(3):242-254
The Clean Development Mechanism (CDM) under the Kyoto Protocol allows industrialized countries to use credits from greenhouse gas (GHG) abatement projects in developing countries. A key requirement of the CDM is that the emission reductions be real, measurable and additional. This article evaluates how the additionality of CDM projects has been assessed in practice. The analysis is mainly based on a systematic evaluation of 93 registered CDM projects and comes to the conclusion that the current tools for demonstrating additionality are in need of substantial improvement. In particular, the application of the barrier analysis is highly subjective and difficult to validate in an objective and transparent manner. Key assumptions regarding additionality are often not substantiated with credible, documented evidence. In a considerable number of cases it is questionable whether the emission reductions are actually additional. Based on these findings, practical recommendations for improving the assessment of additionality are provided.  相似文献   
362.
2000—2019年中国重大生态工程生态效益遥感评估   总被引:1,自引:0,他引:1  
本文提出了重大生态工程实施生态效益评估理论框架,在选取生态系统宏观结构、生态系统质量和生态系统服务3大类、6个一级指标和9个二级指标的基础上,利用地面和遥感数据,结合模型模拟,生成了2000—2019年长时间序列评估指标参数数据集,定量评估了中国重大生态工程实施20年后的生态效益。结果表明:生态恢复程度中等、较高和高的区域面积分别占全国国土面积的24.1%、11.9%和1.7%,生态工程实施数量越多的地区,生态恢复程度越高,生态恢复程度较高和高的区域主要集中在黄土高原、北方农牧交错带、东北平原、川滇黔渝湘结合部等地区;气候因素和生态工程对植被净初级生产力变化的贡献率分别为85.4%和14.6%,对水蚀模数变化的贡献率分别为69.5%和30.5%;中国植被覆盖度有20%的恢复潜力,森林植被覆盖度恢复潜力为6.4%,草地植被覆盖度恢复潜力为23%;气候条件是生态恢复的重要限制因素,生态恢复程度较高和高的区域主要分布在年均温大于0 ℃和年降水量大于300 mm的地区。因此,重大生态工程的部署,应充分考虑气候条件的限制性,避免实施单一生态工程或单一生态恢复措施,充分发挥生态工程组合措施的综合效应,提高生态投入资金的最大效益。  相似文献   
363.
To alleviate the severe rocky desertification and improve the ecological degradation conditions in Southwest China, the national and local Chinese governments have implemented a series of Ecological Restoration Projects (ERPs) since the late 1990s. This study proposed a remote sensing based approach to evaluate the long-term efforts of the ERPs started in 2000. The method applies a time-series trend analysis of satellite based vegetation data corrected for climatic influences to reveal human induced vegetation changes. The improved residual method is combined with statistics on the invested project funds to derive an index, Project Effectiveness Index (PEI), measuring the project effectiveness at county scale. High effectiveness is detected in the Guangxi Province, moderate effectiveness in the Guizhou Province, and low and no effectiveness in the Yunnan Province. Successful implementations are closely related to the combined influences from climatic conditions and human management. The landforms of Peak Forest Plain and Peak Cluster Depression regions in the Guangxi Province are characterized by temperate climate with sufficient rainfall generally leading to a high effectiveness. For the karst regions of the Yunnan and Guizhou Provinces with rough terrain and lower rainfall combined with poor management practices (unsuitable species selection, low compensation rate for peasants), only low or even no effect of project implementations can be observed. However, the effectiveness distribution is not homogeneous and counties with high project effectiveness in spite of complex natural conditions were identified, while counties with negative vegetation trends despite relatively favorable conditions and high investments were also distinguished. The proposed framework is expected to be of high relevance in general monitoring of the successfulness of ecological conservation projects in relation to invested funds.  相似文献   
364.
A method is proposed for the prospecting prediction of subsurface mineral deposits based on soil geochemistry data and a deep convolutional neural network model.This method uses three techniques(window offset,scaling,and rotation)to enhance the number of training data for the model.A window area is used to extract the spatial distribution characteristics of soil geochemistry and measure their correspondence with the occurrence of known subsurface deposits.Prospecting prediction is achieved by matching the characteristics of the window area of an unknown area with the relationships established in the known area.This method can efficiently predict mineral prospective areas where there are few ore deposits used for generating the training dataset,meaning that the deep-learning method can be effectively used for deposit prospecting prediction.Using soil active geochemical measurement data,this method was applied in the Daqiao area,Gansu Province,for which seven favorable gold prospecting target areas were predicted.The Daqiao orogenic gold deposit of latest Jurassic and Early Jurassic age in the southern domain has more than 105 t of gold resources at an average grade of 3-4 g/t.In 2020,the project team drilled and verified the K prediction area,and found 66 m gold mineralized bodies.The new method should be applicable to prospecting prediction using conventional geochemical data in other areas.  相似文献   
365.
Surfboard-making is concentrated in regions with vibrant surfing subcultures, suitable waves and sufficient expertise in crafting boards, by hand, to suit prevailing coastal conditions. This article charts the rise of the Gold Coast as Australia's most concentrated cluster of surfboard-making, from its origins as do-it-yourself craft in backyards and sheds, to professional, export-oriented industry. Out of highly informal, subcultural origins, a regional cluster emerged in the 1960s, fuelled by the growth of surfing, tourism and suburban development, and by the needs of surfers for customised boards that suit their body size, surfing style and local wave conditions. What transpired was a vernacular form of coastal creative industry combining craft skills, subcultural knowledge and design flair. Nevertheless, a mix of factors, including automation, increased competition from cheap imports, increasingly aggressive retail trade, and mistrust among board-makers, has threatened viability. Some workshops overextended into export production, marketing and automation, and consequently suffered from exposure to risk (as well as a commensurate decline in regional tourism). Others survived, and in some ways turned full circle: those small workshops continuing to service local markets, within their means, were most able to ride out the industry's turbulent times. Small-scale cultural production persists despite the volatility of the larger brands, geared instead around loyal customers who want hand-crafted boards made by shapers who they know and trust.  相似文献   
366.
广西田林县高龙金矿成矿模式探讨   总被引:3,自引:1,他引:2  
高龙金矿是滇黔桂金三角典型的微细浸染型金矿床之一,矿体产于中三叠统百逢组硅化砂泥岩中,顶板为中、上三叠统碎屑岩,底板为高龙隆起核部二叠系碳酸盐岩地层。高龙隆起和周缘的断裂系统是金矿产出和形成的关键控矿因素,硅化与金矿化关系十分密切。本文通过对高龙金矿矿床地质特征、元素地球化学、同位素地球化学、流体包裹体等方面的分析研究,认为高龙金矿具有热液石英脉活动强烈、流体形成温度高温可达330~400℃、Au,As,Hg,Sb等元素富集明显、隆起边缘环形断裂导矿明显等特点,初步认为金元素应源自围岩碎屑岩地层,但成矿热液活动则可能与岩浆热液活动有关,成矿流体运移的通道则为隆起边缘的张性断裂系统。最后在本次研究成果基础上,初步建立了高龙金矿成矿模式。  相似文献   
367.
研究发现后期岩浆热液作用是造成哈图金矿床两类金矿体之一的石英脉型矿体的产生,构造活动对金矿体后期变化的影响较小,含矿石英脉上部因风化剥蚀作用消火,勘查中需要考虑矿床后期变化因素.  相似文献   
368.
大麦地金矿为赋存于峨眉山玄武岩组与茅口组之间因区域构造和热液蚀变作用形成的构造蚀变体(Sbt)中的原生中型金矿床,位于贵州西部峨眉山玄武岩分布区盘县莲花山背斜南东翼.本文系统总结大麦地金矿详查成果,以期对莲花山背斜区域原生金矿找矿提供参考,初步认为贵州西部玄武岩分布区原生金矿找矿具有较大的潜力.  相似文献   
369.
基性岩脉与金成矿的关系   总被引:1,自引:0,他引:1       下载免费PDF全文
张良  胡菲菲 《江苏地质》2013,37(2):208-211
基性岩脉是大陆伸展背景下,主要来自陆下软流圈或地幔岩石圈的岩浆侵入岩体.大量研究成果表明基性岩脉发育与金矿脉在空间展布、构造格局和形成时间具有紧密依存关系,虽然对基性岩脉是否为金矿脉提供金源尚无统一定论,但是根据基性岩脉与金矿化紧密的时空关系,基性岩脉可以作为找金矿的良好标志.  相似文献   
370.
基于NDVI时空序列数据,利用GLOPEM-CEVSA模型,本文估算并分析了长江源区1997-2012年植被覆盖度及植被净初级生产力时空变化特征,并在此基础上评估了生态工程实施前、后长江源区宏观生态状况变化。结果表明:工程实施后,长江源区宏观生态状况显著好转,植被覆盖度及植被净初级生产力明显增加。从多年平均值来看,工程实施后,植被覆盖度好转区域面积占植被区总面积的72.10%,净初级生产力增加区域面积占植被区总面积的73.82%;从变化趋势来看,植被覆盖度好转区域面积净增加13.02%,植被净初级生产力好转区域面积净增加24.62%。工程实施前后相比,各流域宏观生态状况恢复程度具有差异,其中楚玛尔河源头植被覆盖度上升最明显,通天河流域植被净初级生产力上升最明显。长江源区宏观生态状况的好转受益于气候的湿润化及生态工程的共同影响,若要全面有效改善仍需持续努力。  相似文献   
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