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81.
Modeling regional initiation of rainfall-induced shallow landslides in the eastern Umbria Region of central Italy 总被引:3,自引:6,他引:3
Diana Salciarini Jonathan W. Godt William Z. Savage Pietro Conversini Rex L. Baum John A. Michael 《Landslides》2006,3(3):181-194
We model the rainfall-induced initiation of shallow landslides over a broad region using a deterministic approach, the Transient Rainfall Infiltration and Grid-based Slope-stability (TRIGRS) model that couples an infinite-slope stability analysis with a one-dimensional analytical solution for transient pore pressure response to rainfall infiltration. This model permits the evaluation of regional shallow landslide susceptibility in a Geographic Information System framework, and we use it to analyze susceptibility to shallow landslides in an area in the eastern Umbria Region of central Italy. As shown on a landslide inventory map produced by the Italian National Research Council, the area has been affected in the past by shallow landslides, many of which have transformed into debris flows. Input data for the TRIGRS model include time-varying rainfall, topographic slope, colluvial thickness, initial water table depth, and material strength and hydraulic properties. Because of a paucity of input data, we focus on parametric analyses to calibrate and test the model and show the effect of variation in material properties and initial water table conditions on the distribution of simulated instability in the study area in response to realistic rainfall. Comparing the results with the shallow landslide inventory map, we find more than 80% agreement between predicted shallow landslide susceptibility and the inventory, despite the paucity of input data. 相似文献
82.
83.
The impact of inhomogenous background errors on a global wave data assimilation system 总被引:1,自引:0,他引:1
One of the main limitations in current wave data assimilation systems is the lack of an accurate representation of the structure of the background errors. In this work, models for the observational error variance, background error variance and background error correlations are developed based on the results of previous studies. These are tested in a global wave data assimilation system and the resulting wave forecasts are verified against independent observations from buoys. Forecasts of significant wave height show substantial improvement over the Australian Bureau of Meteorology's current operational wave forecasting system. However, forecasts of peak period are not similarly improved. The regional impacts of the new assimilation scheme are found to vary on a seasonal basis. Overall, it is shown that the inclusion of a latitudinally dependent background error, and improved specification of the background and observational error variances can reduce the root-mean-square error of 24-hour forecast Significant Wave Height by almost 10%. 相似文献
84.
85.
Seamless integration of spatial statistics and GIS: The S-PLUS for ArcView and the S+Grassland Links
Shuming Bao Luc Anselin Doug Martin Diana Stralberg 《Journal of Geographical Systems》2000,2(3):287-306
The extension of the functional capacity of geographic information systems (GIS) with tools for statistical analysis in general
and exploratory spatial data analysis (ESDA) in particular has been an increasingly active area of research in recent years.
In this paper, two operational implementations that combine the functionality of spatial data analysis software with a GIS
are considered more closely. They consist of linkages between the S-PLUS software for data analysis and two different GIS implementations, the ArcView desktop system, which is mostly vector-oriented, and the primarily raster-based Grassland open GIS environment. We emphasize conceptual and technical issues related to the software implementation of these approaches
and suggest future directions for linking spatial statistics and GIS.
Received: 14 January 1999 / Accepted: 11 May 1999 相似文献
86.
Low-field magnetic susceptibility: a proxy method of estimating increased pollution of different environmental systems 总被引:18,自引:0,他引:18
E. Petrovský A. Kapička N. Jordanova M. Knab V. Hoffmann 《Environmental Geology》2000,39(3-4):312-318
A need for rapid and inexpensive (proxy) methods of outlining areas exposed to increased pollution by atmospheric particulates
of industrial origin caused scientists in various fields to use and validate different non-traditional (or non-chemical) techniques.
Among them, soil magnetometry seems to be a suitable tool, at least in some cases. This method is based on the knowledge that
ferrimagnetic particles, namely magnetite, are produced from pyrite during combustion of fossil fuel. Besides the combustion
processes, magnetic particles can also originate from road traffic, for example, or can be included in various waste-water
outlets. Magnetite, Fe3O4, ranks among the main ferrimagnetic minerals and its identification in various ecosystems can contribute to fast and simple
outlining of areas and sites exposed to higher pollution impact. Here the method of magnetic mapping of anthropogenic pollution
will be introduced using a review of our recent case studies on different ecosystems in the Czech Republic and Germany.
Received: 20 June 1998 · Accepted: 9 November 1998 相似文献
87.
Kátia Martinello James C.Hower Guilherme L.Dotto Claudete G.Ramos Carlos E.Schnorr Diana Pinto 《地学前缘(英文版)》2022,(1):498-505
Because incomplete confirmation is available concerning the influential role of atmosphere contamination on conjunctivitis,myopia,asthma,and allergic rhinitis in Brazil,the focus of the present work is to explore the possible relations among atmosphere contamination and eye problems.Rather that a case study on eye diseases,by way of questionnaires supplemented by the investigation of nanoparticles(NPs)on eyeglasses,the study examines the mechanisms in which NPs and ultra-fine particles are deposited on the glasses of children up to 10 years of age in urban and rural area.The important connection between atmosphere contaminants and individual protection equipment justifies improving indoor school properties in order could protect children’s eyes,particularly in high-pollution/high-particulate areas. 相似文献
88.
Mental preparation for climate adaptation: The role of cognition and culture in enhancing adaptive capacity of water management in Kiribati 总被引:3,自引:0,他引:3
Natasha KuruppuAuthor Vitae Diana LivermanAuthor Vitae 《Global Environmental Change》2011,21(2):657-669
In many Least Developed Countries (LDCs) and Small Island Developing States (SIDS), such as in Kiribati, formal national adaptation programmes are currently being operationalised or are in the pipeline. A key focus is on motivating householders to adapt in anticipation of climate change through pilot community projects. In this paper, we argue that the water sector must pay equal attention to how communities cognitively perceive the process of adaptation if interventions are to be effective. Adopting a cognitive model to gain such insights we conclude that individual's belief in their own abilities to manage water stress play a crucial role in driving intentions to adapt and therefore greater attention needs to be placed on understanding the underling drivers shaping such beliefs. 相似文献
89.
Hana Grison Eduard Petrovský Neli Jordanova Aleš Kapička 《Studia Geophysica et Geodaetica》2011,55(4):697-716
The enhanced magnetic susceptibility of modern soils is assumed to have several reasons including, e.g., weathering of an
iron-rich geological basement, natural fires, bacterial processes and atmospheric deposition of anthropogenic particles. We
report on a case where none of the above sources of magnetic enhancement is evident: a modern soil with high magnetic susceptibility
over the whole soil profile, developed on nonmagnetic limestones, in an area with no industrial activities. The surface magnetic
susceptibility varies from 60 to 110×10−5 SI, while that of the rock basement is nearly zero. Moreover, significant frequency-dependent magnetic susceptibility (>
12%) suggests that superparamagnetic secondary magnetite/maghemite plays an important role. Possible mechanisms, responsible
for this magnetic enhancement, are discussed. 相似文献
90.
Impact of mining activities on sediments in a semi-arid environment: San Pedro River, Sonora, Mexico
Agustín Gómez-Álvarez Jesús L. Valenzuela-García Diana Meza-Figueroa Margarita de la O-Villanueva Jorge Ramírez-Hernández Javier Almendariz-Tapia Efrén Pérez-Segura 《Applied Geochemistry》2011,26(12):2101-2112
A study of the San Pedro River (SPR), which is located in a semi-arid region in Sonora, Mexico, was conducted to evaluate the chemical, spatial and temporal (mobilization) trends of potentially harmful metals in its sediment in the rainy and dry seasons. High total concentrations of metals were detected in the following order: Fe > Cu > Mn > Zn > Pb > Cd. All studied metals except for Pb were increased during the dry season showing the effect of climate on the metal distribution in sediments. The results of sequential extraction indicated that the residual and Fe/Mn oxide fractions were the most important with regard to retaining potentially harmful metals in the sediments. In the exchangeable carbonate and Fe oxide fractions, high concentrations of metals were detected, representing high environmental risk. The geoaccumulation index shows slight to moderate contamination in most samples, and sampling point E4 (related to cattle activity) shows strong contamination for Cd, Cu, Pb and Zn. Enrichment factors (EFs) demonstrate anthropogenic origins for Pb (EF: 3–57), Cd (EF: 6–73) and Cu (EF: 1.5–224). This study shows that sediments are impacted by anthropogenic activities related to the mining industry, untreated wastewater discharges from the city of Cananea and cattle activities. Metal mobility in the SPR can disrupt the development of aquatic species in the river. 相似文献