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991.
使用DEA-Malmquist方法在对比1994~2013年间中国东北三省、东部、中部和西部地区之间创新全要素生产率(TFP)时空差异的基础上,分析了东北三省内部创新TFP的时空演变特征,并运用PVAR模型对东北三省创新TFP的发展趋势进行了预测。研究表明:从空间格局上看东北三省创新TFP增速略高于西部地区,但低于中部和东部地区;东北三省创新TFP增长的主要动力来源于技术进步,在东北三省内部吉林省创新TFP的增长最快,其增长动力主要源于纯效率变化,其次为技术进步;而辽宁省和黑龙江省创新TFP的动力主要是技术进步;预测显示东北三省创新TFP增长幅度未来会逐渐放缓,其增长的主要动力将会由技术进步转变为规模效率的改进。  相似文献   
992.
东北地区未来气候变化对农业气候资源的影响   总被引:5,自引:1,他引:4  
初征  郭建平  赵俊芳 《地理学报》2017,72(7):1248-1260
为探求未来气候变化对东北地区农业气候资源的影响,本文基于区域气候模式系统输出的东北地区IPCC AR5提出的低辐射和高辐射强迫RCP_4.5(低排放)、RCP_8.5(高排放)情景下2005-2099年气象资料,通过与东北地区1961-2010年91个气象站点观测资料同化,分析了历史资料(Baseline)、RCP_4.5、RCP_8.5情景下东北地区农业热量资源和降水资源空间分布及其变化趋势。结果表明:① 年均温度空间分布自南向北降低,未来各地区温度均有升高,RCP_8.5情景下升温更明显,Baseline情景年均温度为7.70 ℃,RCP_4.5和RCP_8.5年均温度分别为9.67 ℃、10.66 ℃;其他农业热量资源随温度变化一致,具体≥ 10 ℃初日提前3 d、4 d,初霜日推迟2 d、6 d,生长季日数延长4 d、10 d,积温增加400 ℃·d、700 ℃·d;水资源稍有增加,但不明显。② 历史增温速率为0.35 ℃/10a,未来增温速率最快为RCP_8.5情景0.48 ℃/10a,高于RCP_4.5的0.19 ℃/10a。21世纪后期,RCP_8.5增温趋势明显快于RCP_4.5,北部地区增温更加速。其他农业热量资源随温度变化趋势相一致,但具体空间分布有所不同。生长季降水总体呈增加趋势,但不显著,年际间变化较大;东部地区降水增加,西部减少。未来东北地区总体向暖湿方向发展,热量资源整体增加,但与降水的不匹配可能将会对农业生产造成不利的影响。  相似文献   
993.
东北地区气候变化CMIP5模式预估   总被引:3,自引:0,他引:3  
利用CMIP5的多模式集合资料,从时间变化和空间分布两方面分析了不同情景下(RCP2.6、RCP4.5、RCP8.5)中国东北地区未来100年的气候变化。结果显示:3种排放情景下,21世纪东北地区气温和降水呈显著增长趋势,中期和末期增幅较明显,冬季增幅高于其他季节,RCP8.5情景下气温增暖最为显著,RCP4.5次之,RCP2.6最小,随着年代的推移,气温和降水年较差逐渐减小;空间分布显示:3种排放情景下各个时期的增温分布形式基本一致,由南向北逐渐增大,辽宁南部增温幅度最小,最显著地区位于黑龙江大兴安岭;不同情景下气温变化率的分布形势略有不同,但均呈显著增温趋势;3种排放情景下降水距平百分率均为增加趋势,呈由东向西逐渐增大的经向分布特征;不同情景下的降水变化率分布形势相似,呈南大北小特征,辽宁地区增长最为明显,黑龙江西部地区增长相对较小。  相似文献   
994.
Geografisk Tidsskrift—Danish Journal of Geography 110(2):155–174, 2010

The Thule culture of the Wollaston-Clavering Ø area is analysed and their settlement pattern as recorded within the area is presented and analysed in relation to the following high arctic seasons: winter, spring and summer. From the analysis it is seen that a defined and stable seasonal mobility between coast, fjords and inland existed and that the “Sirius Water Polynya” off Wollaston Forland and Sabine Ø, holds the key to understanding the human economy and settlement patterns in the research area, as well as in the region.

The cooling of the Little Ice Age, interpreted from the analysed data, does not affect the Inuit exploitation of the research area or their material culture in general. The main Inuit response to the cooling is migration, a response that can only be analysed when Northeast Greenland is studied regionally and interregionally. As migration is defined as an important part of prehistoric ‘Inuit being’, the Inuit made no additional strategies or inventions during the LIA. Inuit migration is, in this way, demonstrated to be a substantial contributor to the Inuit's cultural resilience and to their long-term existence in the Arctic.  相似文献   
995.
Northeast region covers an area of 1.24 million km, making up 12.9% of the total area of China, with a population of 103 million, 9.9% of the total population of China. The grain commodity rate is over 35%. It is one of the very important regions of grain production in China. As population and grain demand unceasingly increase, the potential of grain production, and the commodity grain provided for the nation are the major problems about grain consumption and distribution in the future. And they directly affect the realization of national planning objective of grain production.The analysis of grain production conditions and history indicates that: 1) The increase of total grain output is mainly dependent on the increase of grain yield per unit area, but not the enlargement of grain sown area. 2) The factor to affect grain yield per unit area are materials input, correct policies, yearly climatic variation. 3) By the year 2000 and 2010 the total grain output in this region will be respectively 66.16-66.2  相似文献   
996.
中国东北地区晚侏罗世煤盆地有内陆断陷山间(或山前)盆地和滨海山间断坳盆地两种。内陆盆地具同一演化过程;含煤地层中部深水湖泊相的上、下均含有煤层。滨海盆地另具同一发展过程;含煤性与盆地基底结构、海水进退息息相关。  相似文献   
997.
The reliability of CRU05 rainfall dataset produced by Climatic Research Unit, University of East Anglia is examined against 22 station observations in the northern China. While this dataset has high spatial resolution and long temporal coverage, comparison with station data suggests that it only has higher quality in the last 70 years in the western China. When using this dataset to analyze rainfall variability over the northern China, significant oscillations with periods of 3, 10, and 30 yr are found, with interannual and interdecadal oscillations being the major characteristics of drought and flood events in the region in the last 100 years. Using EOF and REOF analysis, 10 divisions with coherent rainfall variations have been identified, including (i) central Asia and north of Xinjiang, (ii) North China and east of Northwest China,(iii) north and middle of Mongolia, (iv) Hexi Corridor and west of Mongolia, (v)east of the Heilong River,(vi) north of Da Hinggan Mountains, (vii) north of Central Asia, (viii) south of Xinjiang and the Qinghai-Tibetan Plateau, (ix) south of Northeast China, and (x) north of Altay Mountains. Results suggest that the pronounced feature of drought in the arid and semi-arid areas of northern China is not isolated. Of course, it is consistent with rainfall variations in the arid areas of Mongolia and Central Asia. In addition,by analyzing prominent oscillations observed in the last several decades, the trends of rainfall variations over the region in the future 10-15 years are discussed.  相似文献   
998.
LAND RECLAMATION PROCESS IN NORTHEAST CHINA SINCE 1900   总被引:2,自引:1,他引:1  
Landuse/coverchange(LUCC)isafocalthemeandemergingissueinthestudyofglobalenvironmentalchange.Humanmodificationsandalterationstotheenvironmentcauseimpactsonthesurfaceoftheearth,threatenglobalsustainabilityandlivelihoodsystems,andcontributetochangeinthebiogeochemicalcyclesoftheearth,whichinturnaffectatmosphericlevelsofgreenhouseandothertracegases.ConsequentlytheInternationalGeosphere-BiosphereProgram(IGBP)andtheInternationalHumanDimensionsProgram(IHDP)initiatedLUCCProgramtodevelopabette…  相似文献   
999.
This study investigated the drivers and physical processes for the abrupt decadal summer surface warming and increases in hot temperature extremes that occurred over Northeast Asia in the mid-1990 s. Observations indicate an abrupt increase in summer mean surface air temperature(SAT) over Northeast Asia since the mid-1990 s. Accompanying this abrupt surface warming, significant changes in some temperature extremes, characterized by increases in summer mean daily maximum temperature(Tmax), daily minimum temperature(Tmin), annual hottest day temperature(TXx), and annual warmest night temperature(TNx) were observed. There were also increases in the frequency of summer days(SU) and tropical nights(TR).Atmospheric general circulation model experiments forced by changes in sea surface temperature(SST)/ sea ice extent(SIE),anthropogenic greenhouse gas(GHG) concentrations, and anthropogenic aerosol(AA) forcing, relative to the period 1964–93, reproduced the general patterns of observed summer mean SAT changes and associated changes in temperature extremes,although the abrupt decrease in precipitation since the mid-1990 s was not simulated. Additional model experiments with different forcings indicated that changes in SST/SIE explained 76% of the area-averaged summer mean surface warming signal over Northeast Asia, while the direct impact of changes in GHG and AA explained the remaining 24% of the surface warming signal. Analysis of physical processes indicated that the direct impact of the changes in AA(through aerosol–radiation and aerosol–cloud interactions), mainly related to the reduction of AA precursor emissions over Europe, played a dominant role in the increase in TXx and a similarly important role as SST/SIE changes in the increase in the frequency of SU over Northeast Asia via AA-induced coupled atmosphere–land surface and cloud feedbacks, rather than through a direct impact of AA changes on cloud condensation nuclei. The modelling results also imply that the abrupt summer surface warming and increases in hot temperature extremes over Northeast Asia since the mid-1990 s will probably sustain in the next few decades as GHG concentrations continue to increase and AA precursor emissions over both North America and Europe continue to decrease.  相似文献   
1000.
东北地区的创新能力演化及其经济带动作用分析   总被引:5,自引:2,他引:3  
宋周莺  车姝韵  王姣娥 《地理科学》2016,36(9):1388-1396
通过建立创新能力指标体系和计算模型,并采用相关分析、回归分析、变异系数等方法,从不同空间层级剖析了东北三省的创新能力发展格局及其对经济发展的带动作用,并根据研究结果提出了相关政策建议。研究发现:从创新能力分析,吉林、辽宁的创新能力增长较快而黑龙江相对较慢,省际差异呈扩大态势;地级市之间的创新能力相差悬殊,呈现明显的省会城市及门户城市集聚效应,但市级差异呈缩小态势。 从创新贡献率分析,辽宁的科技创新转化能力及其对经济发展的带动相对较强,而吉林、黑龙江相对较弱;地级市差异较大,沈阳、大连、长春、大庆的创新贡献率比较突出,而锦州、吉林、盘锦、铁岭上升较快。大部分地级市的创新发展对经济带动模式为“低创新能力-弱经济带动”和“高创新能力-强经济带动”,说明各地级市的创新发展及其对经济带动的两极分化较严重。  相似文献   
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