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331.
长三角一体化下的金融流动格局变动及驱动机理——基于上市企业金融交易数据的分析 总被引:2,自引:0,他引:2
金融资本是区域进行生产活动并进一步带动经济增长的原动力。结合新经济地理学与金融地理学的理论,将金融资源流动纳入市场化、全球化、分权化和一体化的研究框架之下,用网络分析的方法,构建区域金融流动的格局及机理的分析框架。基于长三角16 市金融发展状况和上市公司2002 年、2005 年、2008 年和2011 年的交易数据,构建了金融资源流动和联系的网络,并进一步测量了网络密度和中心度。结果显示,长三角金融发展与金融资源分布形成了差异显著但有缩小趋势的发展格局,除上海金融中心作用凸显之外,南京、杭州和宁波也成为金融流动网络中的重要空间节点;金融流动网络密度不断增强,跨省金融流动增多。分别选取表征市场化、全球化、分权化和一体化的指标,使用QAP网络分析方法揭示了长三角金融流动的动力机制。相关和回归分析结果表明,进出口总额、FDI、文化差异、外资金融法人数量和行政边界均对金融流动有显著的影响,相反金融业比重和地方财政收入自治率则并无显著作用。本文探讨了从地理学空间差异和空间相互作用的角度来解释金融差异与金融流动的方法,对于深入研究金融一体化问题有借鉴作用。 相似文献
332.
Yehua Dennis Wei Xinyue Ye 《Stochastic Environmental Research and Risk Assessment (SERRA)》2014,28(4):757-765
China’s economic reforms and unprecedented growth have generated many fascinating issues for scholarly research. An understanding of urbanization and land use change in China is required for appropriate strategies and policies to facilitate future sustainable development. This paper reviews the literature on urbanization, land use and sustainable development in China with a focus on land use change. We argue that land use and environmental research are embedded in the complex economic-geographical processes and multiple trajectories of development and urbanization in China. This paper highlights the important role of space–time modeling in a multi-disciplinary setting in the study of urbanization, land use and sustainable development. It also points out potential areas for future research. 相似文献
333.
Climate change impacts on water management and irrigated agriculture in the Yakima River Basin, Washington, USA 总被引:1,自引:0,他引:1
Julie A. Vano Michael J. Scott Nathalie Voisin Claudio O. Stöckle Alan F. Hamlet Kristian E. B. Mickelson Marketa McGuire Elsner Dennis P. Lettenmaier 《Climatic change》2010,102(1-2):287-317
The Yakima River Reservoir system supplies water to ~180,000 irrigated hectares through the operation of five reservoirs with cumulative storage of ~30% mean annual river flow. Runoff is derived mostly from winter precipitation in the Cascade Mountains, much of which is stored as snowpack. Climate change is expected to result in earlier snowmelt runoff and reduced summer flows. Effects of these changes on irrigated agriculture were simulated using a reservoir system model coupled to a hydrological model driven by downscaled scenarios from 20 climate models archived by the 2007 Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report. We find earlier snowmelt results in increased water delivery curtailments. Historically, the basin experienced substantial water shortages in 14% of years. Without adaptations, for IPCC A1B global emission scenarios, water shortages increase to 27% (13% to 49% range) in the 2020s, to 33% in the 2040s, and 68% in the 2080s. For IPCC B1 emissions scenarios, shortages occur in 24% (7% to 54%) of years in the 2020s, 31% in the 2040s and 43% in the 2080s. Historically unprecedented conditions where senior water rights holders suffer shortfalls occur with increasing frequency in both A1B and B1 scenarios. Economic losses include expected annual production declines of 5%–16%, with greater probabilities of operating losses for junior water rights holders. 相似文献
334.
Rudolf Brázdil Petr Dobrovolný Jürg Luterbacher Anders Moberg Christian Pfister Dennis Wheeler Eduardo Zorita 《Climatic change》2010,101(1-2):7-40
Temperature reconstructions from Europe for the past 500 years based on documentary and instrumental data are analysed. First, the basic documentary data sources, including information about climate and weather-related extremes, are described. Then, the standard palaeoclimatological reconstruction method adopted here is discussed with a particular application to temperature reconstructions from documentary-based proxy data. The focus is on two new reconstructions; January–April mean temperatures for Stockholm (1502–2008), based on a combination of data for the sailing season in the Stockholm harbour and instrumental temperature measurements, and monthly Central European temperature (CEuT) series (1500–2007) based on documentary-derived temperature indices of the Czech Republic, Germany and Switzerland combined with instrumental records from the same countries. The two series, both of which are individually discussed in greater detail in subsequent papers in this special edition, are here compared and analysed using running correlations and wavelet analysis. While the Stockholm series shows a pronounced low-frequency component, the CEuT series indicates much weaker low-frequency variations. Both series are analysed with respect to three different long-period reconstructions of the North Atlantic Oscillation (NAO) and are compared with other European temperature reconstructions based on tree-rings, wine-harvest data and various climate multiproxies. Correlation coefficients between individual proxy-based series show weaker correlations compared to the instrumental data. There are also indications of temporally varying temperature cross-correlations between different areas of Europe. The two temperature reconstructions have also been compared to geographically corresponding temperature output from simulations with global and regional climate models for the past few centuries. The findings are twofold: on the one hand, the analysis reinforces the hypothesis that the index-data based CEuT reconstruction may not appropriately reflect the centennial scale variations. On the other hand, it is possible that climate models may underestimate regional decadal variability. By way of a conclusion, the results are discussed from a broader point of view and attention is drawn to some new challenges for future investigations in the historical climatology in Europe. 相似文献
335.
The shared Torres Strait rock lobster (Panulirus ornatus) fishery provides important income for commercial and traditional fishers in Australia and Papua New Guinea. The lobster stock is first fished in Torres Strait by divers from both countries and then becomes vulnerable to Australian prawn trawlers, followed by Papua New Guinea trawlers during its annual breeding migration. Lobster catch sharing arrangements are governed by the Torres Strait Treaty ratified in 1985, but the sequential trawling of breeding lobsters has been controlled by bilateral agreements. A trawl ban was implemented in 1984 in both countries to conserve the breeding stock, but some trawling has been conducted in the Gulf of Papua since then and there is renewed interest in Papua New Guinea to resume trawling. To evaluate the impact of trawling migratory breeding lobsters on the lobster fishery, a model that combines a cohort depletion model with a stock recruitment relationship was developed in this study. The model showed that when the fishery is fully or over‐exploited by the dive fishery, trawling breeding lobsters would reduce both the spawning stock and the total catch of the fishery. The reduction in catch would increase with increasing fishing mortality. If trawling occurred on the Papua New Guinea side only, a redistribution of catch between Australia and Papua New Guinea would result in a small gain in catch for Papua New Guinea at the expense of the Australian dive fishery. But when fishing mortality reaches a certain level, any trawling in any country will incur catch loss to both countries. For the long‐term sustainability and maximum production of the fishery, regulations should be implemented in both countries under a co‐management scheme of a shared fish stock. 相似文献
336.
Two notable species of erect cyclostome bryozoans from a nearshore benthic fauna off Spirits Bay, northernmost New Zealand, are described here for the first time. The first, Spiritopora perplexa gen. et sp. nov., is an endemic cerioporine‐grade genus which is abundant in this area. Colonies are characterised by an unusual combination of fixed‐and free‐walled skeletal morphologies: autozooids forming the extensive encrusting colony bases are normally fixed‐walled, whereas those forming the short, bifoliate erect branches are usually free‐walled. The highly distinctive morphology of S. perplexa, very different from any other fossil or Recent cyclostome, together with its success in overgrowing competitors for space, makes its restricted geographical distribution puzzling and highlights the importance of conservation in this area now closed to trawling, Danish seining, and commercial scallop dredging. The second species, Calvetia osheai sp. nov., is less common, and has small, tree‐like colonies. It is the third species assigned to this distinctive cancellate genus, previously known only from Recent of Tierra del Fuego and the Eocene of Antarctica. 相似文献
337.
YU Guirui CHEN Zhi ZHANG Leiming PENG Changhui CHEN Jingming PIAO Shilong ZHANG Yangjian NIU Shuli WANG Qiufeng LUO Yiqi CIAIS Philippe BALDOCCHI D. Dennis 《资源与生态学报(英文版)》2017,8(2):115-120
As the Earth entering into the Anthropocene, global sustainable development requires ecological research to evolve into the large-scale, quantitative, and predictive era. It necessitates a revolution of ecological observation technology and a long-term accumulation of scientific data. The ecosystem flux tower observation technology is the right one to meet this requirement. However, the unique advantages and potential values of global-scale flux tower observation are still not fully appreciated. Reviewing the development history of global meteorological observation and its scientific contributions to the society, we can get an important enlightenment to re-cognize the scientific mission of flux observation. 相似文献
338.
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340.
Dennis Odijk 《GPS Solutions》2001,5(2):29-42
Due to the maximum of the solar cycle, ionospheric activity increased considerably last year. At frequent times warning were
sent out announcing geomagnetic storms disturbing the ionospheric electron content. In this article the influence of such
geomagnetic storms on fast and precise GPS positioning (for surveying applications at midlatitude regions) is studied. And
here with “fast” it is aimed at the shortest observation time possible: carrier ambiguity resolution and position estimation
using only one single epoch of data. To apply this instantaneous data processing technique successfully to GPS baselines of
medium length (up to 50 km), additional ionospheric information is inevitable, not only under geomagnetic storm but also under
more quiet conditions. However, in this article it will be shown that under geomagnetic storm conditions, even for rather
short baselines (<10 km), for which the ionospheric delays under more quiet conditions could be neglected, one has to account
for significant relative ionospheric delays. Therefore an important facet of this contribution is the investigation of how
to process baselines of varying length in a more uniform way, making use of a permanent GPS network (if available in the surveying
area) and a stochastic modeling technique of the ionospheric delays. ? 2001 John Wiley & Sons, Inc. 相似文献