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京津冀城市群大气污染的时空特征与影响因素解析 总被引:33,自引:5,他引:28
京津冀城市群是中国雾霾最严重的区域,在京津冀协同发展背景下,探究该地区大气污染的时空分布和影响因素具有重要意义。运用空间自相关分析和三种空间计量模型,分析了京津冀202个区县PM2.5的时空分异特征,创新性地对自然与人文影响因素贡献及其空间溢出效应进行系统地甄别和量化。结果表明:2000-2014年来京津冀城市群PM2.5浓度整体呈上升趋势,季节上呈秋冬高、春夏低,空间上呈东南高、西北低的特点,且城市建成区PM2.5浓度比周围郊区和农村平均高10~20 μg/m3;2014年仅有13.9%的区县空气质量达标,PM2.5浓度存在显著的空间集聚性与扩散性,城市间交互影响距离平均为200 km,邻近地区的PM2.5每升高1%,将导致本地PM2.5至少升高0.5%;社会经济内因对PM2.5主要是正向影响,自然外因主要是负向影响;影响因素中对本地大气污染的直接效应贡献强度依次是:年均风速>年均气温>人口密度>地形起伏度>第二产业占比>能源消费>植被覆盖度,人均GDP、年降水量和相对湿度对本地PM2.5没有显著影响;对邻近地区大气污染具有显著空间溢出效应的因素排序是:植被覆盖度>地形起伏度>能源消费>人口密度;对于自然和人文影响因素应分别采取针对性的适应策略和调控策略,加强区域间联防联控与合作治理,在城市群规划中注重环保规划与立法。 相似文献
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GRAPES-MESO模式不同空间分辨率对中国夏季降水预报的影响分析 总被引:3,自引:0,他引:3
国家气象中心业务运行的中尺度数值预报系统GRAPES-MESO(Global/Regional Assimilation and Prediction System mesoscale model)在升级到4.0版本后采用了与以往版本不同的三维空间分辨率设置,本文通过计算精度分析、个例分析及统计分析的方法详细阐述了两者水平分辨率和不等距垂直分层的差异,并由此深入分析了不同模式三维空间分辨率对中国夏季汛期降水预报的影响。主要结论表明,GRAPES-MESO预报系统4.0版本在水平分辨率提高到10 km并同时使用更为合理的加密垂直分层设置后,不仅提高了计算精度和计算稳定性,同时仍能满足业务预报的时效要求。对个例降水特征的分析结果表明,提高模式空间分辨率可以在一定程度上改善对降水中心的预报,但对降水落区的预报改进较为有限。对2012年7月整月批量试验的统计检验结果表明,月平均技巧评分总体变化不大,但对逐日大到暴雨评分提高较大,通过各气象要素统计检验分析可以认为,模式空间分辨率提高的主要作用是通过降低了中低层高度场、温度场和水平风场的误差,改进了对流层中层环流背景场以及对流层低层降水直接触发系统的强度预报,从而能够提高大到暴雨的降水评分。 相似文献
214.
This study explores the main direct and underlying causes of deforestation in Brazil's Legal Amazon region by considering spatial differences. The computation of localized parameters is based on geographically weighted regression (GWR). The novelty of this paper lies in its incorporation of economic, rather than Euclidean, distances into the GWR. Economic distances are measured by travel time, sourced from Google Inc. A global approach revealed several important factors that affect deforestation, including: rural population, GDP (suggesting a U-shaped environmental Kuznets curve), forest stock, cattle ranching, timber value, and road networks (both official and unofficial). Local analysis uncovered patterns not seen under global models, especially in the state of Pará. Most notably, crop cultivation was found to accelerate deforestation in southeastern Pará and northeastern Mato Grosso, while in some regions (especially in the northeastern corner of Pará), the area covered by crop plantations was negatively associated with deforestation. For Pará, rural credit constraints, larger territories designated as sustainable use areas and indigenous lands, and higher levels of precipitation inhibit deforestation. Further, rural population has a very heterogeneous impact on deforestation across Legal Amazon: it is not a significant factor of deforestation in northern Pará and Amapá, but it has a relatively strong effect in the western parts of Mato Grosso and Rondônia. Also, official and illegal roads create significantly more pressure on forests in remote regions compared to developed areas. Finally, the use of economic distances, as opposed to Euclidean distances, leads to notably different GWR results. 相似文献
215.
Understanding the geographical preferences of international tourists is critical for the tourism planning and marketing. However, it is not an easy endeavor to gather the corresponding information, given the absence of city-level tourism statistical data and high costs of participant survey. This paper characterizes the geographical preferences of international tourists using geo-tagged photos on social media (the Flickr in particular). Data are harvested for 333 prefecture-level cities in China from 2008 to 2013, and the intensity of photo sharing (IPS: the ratio between total number of uploaded photos and total area of the city/region) is used an indicator of tourist geographical preferences. IPS visualization shows the geography that tourism hotpots generally concentrate in regional capital cities and economically developed megaregions. More specifically, the East Asia and Oceania tourists exhibit more preferences towards the eastern coastal cities, while the Europe and North America visitors show increasing interest in exploring the western and northern places. Spatial regression is employed to quantify the local influential factors of tourists’ geographical preferences. It is found that international tourists usually consider the local economy, accessibility, infrastructure and cultural attractions when they choose their destinations in China. East Asia and Oceania visitors particularly appreciate the local economy and cultural attractions. Europe and North America tourists especially value the cultural attractions and local openness. The demonstrated methodological framework is not restricted to Flickr data, and it can be applicable to social media offer geo-tagging service. This paper is therefore believed to advance the applications of social media into geographical research. 相似文献
216.
对基础地学空间数据库建设中的多源数据的集成问题进行了理论上和方法上的探讨,并以WebGIS可视化信息系统为例,讨论了数据标准、整理原则和集成方法。针对数据集成中的几个问题提出了解决方案,对涉及到的关键技术进行了分析。 相似文献
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Laura M. Kracker 《The Professional geographer》1999,51(3):440-450
Rather than seeing the oceans as an expansive void, researchers using acoustic technologies can detect the heterogeneity of biological resources and view the marine environment as a three-dimensional landscape. Underwater remote sensing, using acoustics, provides high resolution maps of the spatial distribution of organisms in aquatic ecosystems. Analyzing the spatial pattern of species distribution within the water column and the impact of that organization on ecological processes bridges the fields of fisheries and spatial analysis. Tools and concepts familiar to geographers, such as remote sensing, GIS, and landscape ecology, contribute to the investigation of large lake and marine ecosystems. 相似文献
220.
《The Professional geographer》1999,51(3):469-479
Rosa Ainley (ed.) New Frontiers of Space, Bodies and Gender David Bell and Gill Valentine (eds.) Consuming Geographies: We Are What We Eat Ruth Fincher and Jane M. Jacobs (eds.) Cities of Difference Richard Grant and Jan Nihman (eds.) The Global Crisis in Foreign Aid Martin Kellman and Rosanne Tackaberry Tropical Environments: The Functioning and Management of Tropical Ecosystems Glenn R. McGregor and Simon Nieuwolt Tropical Climatology Martin Oppermann (ed.) Sex Tourism and Prostitution: Aspects of Leisure, Recreation, and Work Keith Smith and Roy Ward Floods: Physical Processes and Human Impacts 相似文献