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81.
For assessing the social dimension of vulnerability, population exposure mapping is usually considered the essential starting point. Integration of social structure then further differentiates situation-specific vulnerability patterns on a local scale. Census data available in heterogeneous spatial reference units are still considered the standard information input for assessing potentially affected people, for example, in case of an emergency. There is a strong demand for population data in homogeneous spatial units that are independent from administrative areas. Raster representations meet this demand but are not yet available for all European countries. In this paper, we present an approach of spatial disaggregation of population data for a European transect referring to current population statistics and anticipated future prospects. Recently published data providing the degree of soil sealing are applied as basic proxy for population density in the spatial disaggregation model. In order to assess future patterns of climate change-related vulnerability, results of a European regional climate model are considered for projecting the situation in the 2030s. “Heat wave frequency” is accounted for as climate variable featuring conditions regarded as especially strenuous for elderly or physically weak persons. Integrated analysis of the population and climate prospects enables identification of hot spots in the European transect examined, that is, regions of particularly demanding projected climatic patterns as well as high population density and case-specific vulnerable structure (elderly people). Integrated and consistent spatial analyses on European scale are essential for decision support in the context of climate change impact mitigation as well as for risk communication and future safety and security considerations.  相似文献   
82.
Zusammenfassung Die Serien der Schuppenzone Elbas zeigen eine durchlaufende stratigraphische Folge vom Paläozoikum bis ins Tertiär. Ein intensiver ostvergenter Falten- und Schuppenbau führt zu einer mehrmaligen Wiederholung bestimmter Gesteinsserien. Es sind 5 größere Schuppen oder Schuppenzonen auszuscheiden, die dem im Süden sich heraushebenden Autochthon überschoben sind. Die syntektonisch aufgedrungenen Granite haben das tektonische Geschehen beeinflußt. Das benachbarte Festland und das übrige toskanische Archipel zeigen denselben Baustil wie die Insel.
Imbricated zones of the Isle of Elba display a continuous sequence from Paleozoic to Tertiary beds in several repetitions. Five larger thrust-zones override an autochthonous Eastern unit which appears (tilted up) in the South. Syntectonic granites. The tectonic style corresponds to the neighbouring continental situation.

Résumé Les séries de la zone des écailles de l'île d'Elbe montrent une succession stratigraphique continue allant du Paléozoïque jusqu'au Tertiaire. Une structure en écailles et en plis fortement déversés vers l'est amène de nombreuses répétitions de certaines séries de roches. On peut distinguer 5 écailles et zones d'écaillés majeures qui sont refoulées sur l'autochtone affleurant au Sud. Les granites, mis en place syntectoniquement, ont influencé la tectonique. Le continent avoisinant et le reste de l'archipel toscan montrent le même style structural que les îles.

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83.
A suite of metasomatised xenoliths from the Letlhakane kimberlite (Botswana) forms a metasomatic sequence from garnet peridotite to garnet phlogopite peridotite to phlogopite peridotite. Before the modal metasomatism, most of the Letlhakane xenoliths were depleted harzburgites that had been subjected to an earlier cryptic metasomatic event. Modal phlogopite and clinopyroxene - Cr-spinel increase at the expense of garnet and orthopyroxene with increasing degrees of metasomatism. The most metasomatised xenolith is a wehrlite. With progressive modal metasomatism, the clinopyroxene becomes enriched in Sr, Sc and the LREE, orthopyroxene becomes depleted in Ca and Ni, but enriched in Al and Mn, and olivine becomes depleted in Al and V. Garnet chemical composition largely remains unchanged. The garnet replacement reaction seen in most xenoliths allows the measurement of the flux of trace elements through detailed modal analysis of the pseudomorphs. Mass balance calculations show that the modally metasomatised rocks became enriched in incompatible elements such as Sr, Na, K, the LREE and the HFSE (Ti, Zr and Nb). Major elements (Al, Cr and Fe) and garnet-compatible trace elements (V, Y, Sc, and the HREE) were removed during this metasomatic process. The modal metasomatism caused a strong depletion in Al, and the results challenge previous suggestions that this metasomatic process merely occurred within an Al-poor environment. The data suggest that the xenoliths represent the mantle wallrock adjacent to a major conduit for an alkaline basic silicate melt (with high contents of volatile and incompatible elements). The volatile and incompatible element-enriched component of this melt percolated into the wallrock along a strong temperature gradient and caused the observed range of metasomatism.  相似文献   
84.
A GIS-based model framework, designed as a raster module for the Open Source software GRASS, was developed for simulating the mobilization and motion of debris flows triggered by rainfall. Designed for study areas up to few square kilometres, the tool combines deterministic and empirical model components for infiltration and surface runoff, detachment and sediment transport, slope stability, debris flow mobilization, and travel distance and deposition. The model framework was applied to selected study areas along the international road from Mendoza (Argentina) to Central Chile. The input parameters were investigated at the local scale. The model was run for a number of rainfall scenarios and evaluated using field observations and historical archives in combination with meteorological data. The sensitivity of the model to a set of key parameters was tested. The major scope of the paper is to highlight the capabilities of the model—and of this type of models in general—as well as its limitations and possible solutions.  相似文献   
85.
The aquifer Westliches Leibnitzer Feld, Austria, is a significant resource for regional and supraregional drinking water supply for more than 100,000 inhabitants, but the region also provides excellent agricultural conditions. This dual use implicates conflicts (e.g., non-point source groundwater pollution by nitrogen leaching), which have to be harmonized for a sustainable coexistence. At the aquifer scale, numerical models are state-of-the-art tools to simulate the behavior of groundwater quantity and quality and serve as decision support system for implementing groundwater protecting measures. While fully and iteratively coupled simulation models consider feedback between the saturated and unsaturated zone, sandy soil conditions and groundwater depths beneath the root zone allow the use of a unidirectional sequential coupling of the unsaturated water flow and nitrate transport model SIMWASER/STOTRASIM with FEFLOW for the investigation area. Considering separated inputs of water and nitrogen into groundwater out of surface water bodies, agricultural, residential and forested areas, first simulation results match observed groundwater tables, but underestimate nitrate concentrations in general. Thus, multiple scenarios assuming higher nitrogen inputs at the surface are simulated to converge with measured nitrate concentrations. Preliminary results indicate that N-input into the groundwater is strongly dominated by contributions of agricultural land.  相似文献   
86.
Planning the use of fish for food security in the Pacific   总被引:1,自引:0,他引:1  
Fish is a mainstay of food security for Pacific island countries and territories (PICTs). Recent household income and expenditure surveys, and socio-economic surveys, demonstrate that subsistence fishing still provides the great majority of dietary animal protein in the region. Forecasts of the fish required in 2030 to meet recommended per capita fish consumption, or to maintain current consumption, indicate that even well-managed coastal fisheries will only be able to meet the demand in 6 of 22 PICTs. Governments of many PICTs will need to increase local access to tuna, and develop small-pond aquaculture, to provide food security. Diversifying the supply of fish will also make rural households in the Pacific more resilient to natural disasters, social and political instability, and the uncertainty of climate change.  相似文献   
87.
GNSS receivers estimate 3D antenna position and receiver clock bias when at least four satellites are tracked. If only three satellites are available, a 2D antenna position solution is still possible. We derive an almost exact algorithm for the determination of two possible antenna positions and the corresponding receiver clock biases based on pseudorange measurements to three GNSS satellites and a height measurement. The two ambiguous solutions exactly reflect the same height measurement. One of the solutions can be eliminated if some prior knowledge of the user position, for example, near the Earth, is available. In general, a less accurate height measurement gives a less accurate 2D GNSS solution, and vice versa. The determination of the receiver antenna position is based upon the intersection of two confocal hyperboloid sheets and the ellipsoid, resulting in a hyperbola along which the user is located. The algorithm is verified by numerical computations.  相似文献   
88.
The current study deals with a parameterization of diapycnal diffusivity in an ocean model. The parameterization estimates the diapycnal diffusivity depending on the location of tidal-related energy dissipation over rough topography. The scheme requires a bottom roughness map that can be chosen depending on the scales of topographic features. Here, we implement the parameterization on an ocean general circulation model, and we examine the sensitivity of the modeled circulations to different spatial scales of the modeled bottom roughness. We compare three simulations that include the tidal mixing scheme using bottom roughness calculated at three different ranges of spatial scales, with the largest scale varying up to 200?km. Three main results are discussed. First, the dependence of the topographic spectra with depth, characterized by an increase in spectral energy over short length scales in the deep ocean, influences the vertical profile of the diffusivity. Second, the changes in diffusivities lead to different equilibrium solutions in the Atlantic meridional overturning circulation and bottom circulation. In particular, the lower cell of the Atlantic overturning and the bottom water transport in the Pacific Ocean are stronger for stronger diffusivities at the corresponding basins and depths, and the strongest when using the small-scale roughness map. Third, a comparison of the density fields of the three simulations with the density field of World Ocean Atlas dataset, from which the models are initialized, shows that among the simulations with three different roughness maps, the one using small-scale bottom roughness map has the smallest density bias.  相似文献   
89.
A sediment core section from Längsee, a small meromictic lake in the southern Alpine lowland (Carinthia, Austria) close to the Würmian ice margin, was investigated by means of diatoms and pollen. The main aims of the study were to reconstruct water temperature as a signal of climate change during the last glacial termination, compare the aquatic and terrestrial response to the changing climate, and place our findings into a climatic frame on the northern hemispheric scale. A calibration data set (ALPS06) of 116 lakes was constructed using data from newly studied lakes and from two previously published data sets and we established a transfer function for predicting summer epilimnetic water temperatures (SEWT). A locally weighted weighted average regression and calibration model (R jack 2  = 0.89; RSMEP = 1.82°C) was applied to the fossil diatom assemblages in order to reconstruct SEWT. Three major sections were distinguished in the time window of approximately 19–13 cal ka BP, which fitted well with the oxygen isotope curve and the isotope-event stratigraphy from the Greenland ice-core GRIP. The first section was a warming period (SEWT range from 11.6 to 18.0°C; average 15.8°C = ca. 6°C below present) called the Längsee oscillation, which probably correlates with the warmer sub-section (GS-2b) of the Greenland Stadial 2. The subsequent section represents a climate cooling, called the Längsee cold period (SEWT range between 10.6 and 15.9°C; average 12.9°C), which probably corresponds with the sub-section GS-2a of the Greenland Stadial 2, the Heinrich 1 cold event of the North Atlantic, and partially the Gschnitz Stadial in the Alps. The Längsee cold period shows a tri-partition: Two colder phases are separated by a warmer inter-phase. The passive ordination of the core sample scores along maximum water depth indicated that the Längsee cold period was drier than the Längsee oscillation. Strong short-term fluctuations during the Längsee oscillation and the Längsee cold period indicate climate instability. The third section represented climate warming during the Längsee late glacial interstadial (=Greenland Interstadial 1, GI-1) with an average SEWT of 17.5°C. From the minor climatic fluctuations during this interstadial, mainly indicated by pollen, the fluctuation most likely related to the Gerzensee oscillation showed a SEWT decline. During the early immigration and expansion period of shrubs and trees, aquatic and terrestrial records showed distinct discrepancies that might have arose because of time lags in response and differences in sensitivity.  相似文献   
90.
Subsidence analysis of 16 wells in the Austrian Molasse basin documents major spatial and temporal changes in tectonic subsidence as well as a late-stage surface uplift. The timing of the main phase of tectonic subsidence shifted from early Oligocene in the western part of the peripheral foreland to the early Miocene in the eastern part. These temporal and spatial changes in tectonic subsidence reflect a change from oblique dextral to sinistral convergence between the Alpine nappe stack and its foreland. The main phase of sediment accumulation was delayed to the early Miocene and led to the infill of the basin and a major second, sediment-load driven phase of basement subsidence. Sediment accumulation rates in the basin reflect the build-up of topography in the Alpine mountain chain. Since approximately 6 Ma a pronounced regional uplift of the entire Molasse basin has taken place, marking the transition from lateral extrusion to orthogonal contraction within the Alpine system and deep-seated changes in geodynamic boundary conditions, possibly due to delamination of previously thickened lithosphere. Surface uplift is contemporaneous with similar processes in extra-Alpine Central Europe, where it is interpreted to reflect intra-plate stress changes.  相似文献   
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