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521.
Francisco Javier Monclús 《GeoJournal》2000,51(1-2):57-63
Planning strategies in Barcelona are linked to its capital city aspirations. Like other European cities, capitals and non-capitals, Barcelona throughout the course of the 20th century has drawn upon a number of different planning strategies, directed towards reinforcing its prestige at both a national and international level. During this period Barcelona has sought to become Spain's second capital, the cultural capital, the industrial capital, capital of Catalonia, capital of the West Mediterranean, etc. Always in competition with Madrid, the aspirations of capital status ranking have been ambiguous. The dream of the great monumental Barcelona of the start of the century tried to emulate the European capital cities (especially Paris). By contrast more recent strategies emphasise the new role that Barcelona can play within a south-west European macro-region. The subject raised in this paper then is two-fold. On the one hand the continuity or not in the capital aspiration starting from the recuperation of Catalonia's autonomy, with its corresponding urbanistic and architectonic connotations. On the other hand the originality and analogies between strategies carried out in Barcelona, in relation to other European cities, capitals and non-capitals. 相似文献
522.
Javier Pereda-Suberbiola 《地学学报》1992,4(6):641-648
Nodosaurid ankylosaurs illustrate well the differences between European and North American faunal assemblages during the Late Cretaceous. A revised checklist of the nodosaurid specimens from the Late Cretaceous (mainly Campanian and Maastrichtian) localities of Europe reveals a more important diversity than commonly envisaged, with at least two distinct species represented. Struthiosaurus nustriacus and a new nodosaurid from the Basque-Cantabric Basin were small (body length about 3 m), presumably dwarf insular forms. AIthough a detailed stratigraphic correlation is not yet availabIe, the disappearance orrelationisnotof the nodosaurids in the Western Interior of North America and in Europe may not be simultaneous but asynchronous. If so, the extinction of the Nodosauridae occurred in the latest Maastrichtian and Struthiosaurus could be the last representative of the group. 相似文献
523.
Arkin Yaacov Karnieli Arnon Issar Arie Mtz.-Esparza Javier Diaz 《Environmental Geology》1986,8(4):185-192
Accelerated erosion of a desert cliff due to uncontrolled sewage water disposal was investigated at the Sede Boqer Campus
in the Negev, Israel An erosional cirque formed by this water was studied as a model simulating natural processes. The cliffs
consist of loess and conglomerate underlain by soft marl, clay, and chalk.
The rate of erosion is of the order of 5%–8% of the volume of water discharged. The rate of incision ranges from 10 2 to 13.3
m/yr and is several orders higher than that expected under normal rainfall conditions
The introduction of this new hydrological factor resulted in a severe disturbance of the morphological balance in the vicinity
of the cliffs, accelerated erosion, and generated circular slides 相似文献
524.
Luis M. Sender Jos B. Diez Javier Ferrer Denise Pons Cristbal Rubio 《Cretaceous Research》2005,26(6):898-905
A newly discovered plant fossil assemblage in the Albian Escucha Formation, located at Valle del Río Martín (Teruel, Spain), shows similarities with the classic early Cretaceous flora of the Potomac Group in the USA. This is the first time that a flora of this age and composition has been found in Spain. It comprises representatives of ferns, Ginkgoales, Bennettitales, Caytoniales, conifers and angiosperms and suggests a possible mixing of the European and Potomac provinces in the early Cretaceous within the Iberian Peninsula, in a subtropical, semi-arid climate. 相似文献
525.
Javier Sánchez-España Francisco Velasco Adrian Joseph Boyce Fernando Tornos 《Mineralium Deposita》2006,40(6-7):749-754
526.
Ángel Fernández-Cortés José María Calaforra Javier García-Guinea 《Environmental Geology》2006,50(5):707-716
The discovery of the giant Geode of Pulpí (Almería, Spain) was considered as an important highlight in the geological heritage of Spain. Projects developed for their conservation were immediately initiated with legal figures of protection and tourist projects. The Geode has a tourist interest, which must be tempered by environmental restrictions limiting the public visits. First results demonstrate that a continuous visit of two or three people for more than 10 min provokes the appearance of condensation and risks corrosion of the gypsum crystals. In addition, the electron microprobe analyses confirms (1) the hydrothermal phases of iron–manganese in carbonated host rock; (2) the presence of sulphides with Fe–Zn–Pb–Ag–Sb–Cu–Hg–As–Te–Se; and (3) Ba, Ca, and Sr sulphates with mercury traces. The present proposal to label the geode and the mining environment as geological-natural heritage is feasible, although any tourist adaptation must not permit visits to the geode indoor and Hg levels must be controlled. 相似文献
527.
Luis Gómez-Orellana Pablo Ramil-Rego Javier Ferreiro da Costa Castor Muñoz Sobrino 《Boreas: An International Journal of Quaternary Research》2021,50(4):1131-1145
The intertidal environment of the Ponzos beach (NW Iberian Peninsula) hosts a sedimentary sequence (including large wood fragments) deposited during the first half of the Holocene in a hygrophilous continental wetland. Pollen and macrofossil data alongside radiocarbon dating allow reconstruction of the changes that occurred during the Early and Middle Holocene in the landscape of the NW Iberia coastal lowlands, as well as the local wetland plant communities, in response to the climate variations and the eustatic sea-level oscillations. The sequence represents the evolution of a coastal wetland from its initial phases as a hygrophilous wetland towards the subsequent installation of a freshwater lagoon. Pollen data show the dominant role of Atlantic (mainly deciduous) woody taxa, the scarcity of conifers and the lack of Mediterranean elements in the coastal landscapes around the Ponzos site. The presence and abundance of some taxa such as deciduous Quercus, Castanea, Fagus, Tilia and Ulmus during the Early Holocene provides further support for the occurrence of glacial refuges in the Cantabrian-Atlantic area during the Last Glaciation. The diverse vegetation that characterizes the modern landscapes in this territory established later, spreading from these glacial reservoirs of biodiversity. In this sense, the notable and early presence of Fagus at the beginning of the Holocene, a tree also previously recorded during several phases of the Last Glacial Cycle on the NW Iberia coasts, is noteworthy. In addition, during the Early and Middle Holocene are recorded other trees that are currently extirpated as natural taxa in the area, such as Pinus, Tilia and Carpinus. 相似文献
528.
Hron Karel Coenders Germá Filzmoser Peter Palarea-Albaladejo Javier Faměra Martin Matys Grygar Tomáš 《Mathematical Geosciences》2021,53(7):1643-1666
Mathematical Geosciences - Even though the logratio methodology provides a range of both generic, mostly exploratory, and purpose-built coordinate representations of compositional data, simple... 相似文献
529.
The spatial–temporal patterns of cloud-to-ground (CG) lightning covering the period 2010–2015 over the northwest Iberian Peninsula were investigated. The analysis conducted employed three main methods: the circulation weather types developed by Jenkinson and Collison, the fit of a generalized additive model (GAM) for geographic variables, and the use of a concentration index for the ratio of lightning strikes and thunderstorm days. The main activity in the summer months can be attributed to situations with eastern or anticyclonic flow due to convection by insolation. In winter, lightning proves to have a frontal origin and is mainly associated with western or cyclonic flow situations which occur with advections of air masses of maritime origin. The largest number of CG discharges occurs under eastern flow and their hybrids with anticyclonic situations. Thunderstorms with greater CG lightning activity, highlighted by a higher concentration index, are located in areas with a higher density of lightning strikes, above all in mountainous areas away from the sea. The modeling of lightning density with geographic variables shows the positive influence of altitude and, particularly, distance to the sea, with nonlinear relationships due to the complex orography of the region. Likewise, areas with convex topography receive more lightning strikes than concave ones, a relation which has been demonstrated for the first time from a GAM. 相似文献
530.
Eulogio Pardo-Igúzquiza Peter Dowd Antonio Pulido Bosch Juan A. Luque-Espinar Javier Heredia Juan J. Durán-Valsero 《Hydrogeology Journal》2018,26(8):2617-2627
A mathematical model of a highly heterogeneous functioning karst aquifer is described. The aquifer is in a high-relief karst massif and, as is common for such locations, data are scarce and there are no borehole, piezometer or pumping-test data. The scarcity of data in this case required a parsimonious approach to ensure that the level of complexity of the model was commensurate with the amount, type and quality of the available data. Parsimony also requires the model to include the minimum essential components that account adequately for the data, which in this and similar cases are the functional dualities of the karst system: duality in recharge, flow and discharge. The model is three-dimensional (3D) in the sense that the aquifer is discretized into 3D voxels, although the flow is one-dimensional (1D) and vertical in the vadose zone, and horizontal and two-dimensional (2D) in the saturated zone. The parsimonious model was designed by coupling a 1D unsaturated gravity-driven flow along the vertical (along each column of voxels that discretize the aquifer) and a 2D unconfined Darcy flow in the saturated zone. In the context of this type of aquifer, preferential recharge through the network of karst conduits implies a rapid rise in the water table, the location and extension of which are model parameters. The karst springs are simulated by drains. The methodology, which is completely general, is illustrated by application to the karst aquifer in the Sierra de las Nieves mountains in southern Spain. 相似文献