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231.
The influence of the environment and environmental change is largely unrepresented in standard theories of migration, whilst recent debates on climate change and migration focus almost entirely on displacement and perceive migration to be a problem. Drawing on an increasing evidence base that has assessed elements of the influence of the environment on migration, this paper presents a new framework for understanding the effect of environmental change on migration. The framework identifies five families of drivers which affect migration decisions: economic, political, social, demographic and environmental drivers. The environment drives migration through mechanisms characterised as the availability and reliability of ecosystem services and exposure to hazard. Individual migration decisions and flows are affected by these drivers operating in combination, and the effect of the environment is therefore highly dependent on economic, political, social and demographic context. Environmental change has the potential to affect directly the hazardousness of place. Environmental change also affects migration indirectly, in particular through economic drivers, by changing livelihoods for example, and political drivers, through affecting conflicts over resources, for example. The proposed framework, applicable to both international and internal migration, emphasises the role of human agency in migration decisions, in particular the linked role of family and household characteristics on the one hand, and barriers and facilitators to movement on the other in translating drivers into actions. The framework can be used to guide new research, assist with the evaluation of policy options, and provide a context for the development of scenarios representing a range of plausible migration futures.  相似文献   
232.
In order to perform hydrological studies on the PRUDENCE regional climate model (RCM) simulations, a special focus was put on the discharge from large river catchments located in northern and central Europe. The discharge was simulated with a simplified land surface (SL) scheme and the Hydrological Discharge (HD) model. The daily fields of precipitation, 2 m temperature and evapotranspiration from the RCM simulations were used as forcing. Therefore the total catchment water balances are constrained by the hydrological cycle of the different RCMs. The validation of the simulated hydrological cycle from the control simulations shows that the multi-model ensemble mean is closer to the observations than each of the models, especially if different catchments and hydrological variables are considered. Therefore, the multi-model ensemble mean can be used to largely reduce the uncertainty that is introduced by a single RCM. This also provides more confidence in the future projections for the multi-model ensemble means. The scenario simulations predict a gradient in the climate change signal over Northern and Central Europe. Common features are the overall warming and the general increase of evapotranspiration. But while in the northern parts the warming will enhance the hydrological cycle leading to an increased discharge, the large warming, especially in the summer, will slow down the hydrological cycle caused by a drying in the central parts of Europe which is accompanied by a reduction of discharge. The comparison of the changes predicted by the multi-model ensemble mean to the changes predicted by the driving GCM indicates that the RCMs can compensate problems that a driving GCM may have with local scale processes or parameterizations.  相似文献   
233.
Within the framework of the Tropospheric Research Programme (TFS) four working groups in Germany (University of Stuttgart, University of Cologne, Research Center Karlsruhe, German Weather Service) formed a network developing a model system for chemistry transport calculations on different scales. The network was optimized, based on each module and combined for the different interfaces in order to perform daily preoperational ozone forecasts and its precursors at the German Weather Service in summer 1999 (May through September). The setup of the model system, the interfaces and changes of each module are described. The results of the whole preoperational episode are displayed and discussed. Main efforts were done analyzing the model climate statistics and the verification of the predictions with an extensive data base of observations at stations in Germany. The results of this extensive verification demonstrate the relatively good performance of the entire forecast system.  相似文献   
234.
Climate change tends to negatively affect the power sector, inter alia, by causing cooling problems in power plants and impairing the water supply required for hydropower generation. In the future, when global warming is expected to increase, autonomous adaptation to climate change via international electricity markets inducing reallocations of power generation may not be sufficient to prevent supply disruptions anymore. Furthermore, the consequent changes of supply patterns and electricity prices might cause an undesirable redistribution of wealth both between individual power suppliers and between suppliers and consumers. This study ascertains changes in European power supply patterns and electricity prices caused by on-going global warming as well as the associated redistribution of wealth for different climate change scenarios. The focus of the analysis is on short-term effects. Our results confirm that autonomous adaptation in the power sector should be complemented by planned public adaptation in order to preserve energy security and to prevent undesired distributional effects.  相似文献   
235.
This paper reviews the potential vulnerability of solar energy systems to future extreme event risks as a consequence of climate change. We describe the three main technologies likely to be used to harness sunlight—thermal heating, photovoltaic (PV), and concentrating solar power (CSP)—and identify critical climate vulnerabilities for each one. We then compare these vulnerabilities with assessments of future changes in mean conditions and extreme event risk levels. We do not identify any vulnerabilities severe enough to halt development of any of the technologies mentioned, although we do find a potential value in exploring options for making PV cells more heat-resilient and for improving the design of cooling systems for CSP.  相似文献   
236.
Bulletin of Earthquake Engineering - In this study a timber-based integrated solution is presented to solve at once common issues affecting typical reinforced concrete (RC) existing buildings, such...  相似文献   
237.
The quaternary coastal Collo aquifer in northeast Algeria (NE Algeria) marks an important local water resource supporting domestic, industrial and agricultural activities. The aquifer shows signs of contamination due to the existence of various pollution sources, especially nitrogen compounds. Focusing the local identification of key vulnerable zones and related main hazard types for wise future water management, the present study highlights results from a coupled analysis of the well-established Geographical Information System (GIS)-based GOD (groundwater occurrence, overall aquifer class, depth to groundwater) hazard index analysis and the COST Action 620 plan. Most prevalent hazard types in the study area were identified as the urban/residential areas without public sewage systems, landfill and agricultural/pasturing areas. Regarding the vulnerability analysis particularly the northern aquifer region is endangered, dominated by high (22.4%) and moderate (27.4%) vulnerability classes. Central, western and southern aquifer regions are characterized by low (23.3%) and very low (26.9%) vulnerability classes. Overall, these GOD-derived results are in good agreement with earlier results obtained by the more complex DRASTIC approach. Final risk assessment and validation related to 2014/2015 nitrate sampling campaigns indicate that “high risk” and “very high risk” classes only apply to a small part of the study area in the northern sector (8%), whereas the main part (>60%) broadly affecting the central, western and southern sector only bears a low to very low risk of water pollution. Apart from a future-oriented groundwater abstraction strategy it is recommended to update the evaluation regularly to effectively consider dynamic changes of local anthropogenic activities and hazards.  相似文献   
238.
The development of better, more reliable and more efficient susceptibility assessments for shallow landslides is becoming increasingly important. Physically based models are well-suited for this, due to their high predictive capability. However, their demands for large, high-resolution and detailed input datasets make them very time-consuming and costly methods. This study investigates if a spatially transferable model calibration can be created with the use of parameter ensembles and with this alleviate the time-consuming calibration process of these methods. To investigate this, the study compares the calibration of the model TRIGRS in two different study areas. The first study area was taken from a previous study where the dynamic physically based model TRIGRS was calibrated for the Laternser valley in Vorarlberg, Austria. The calibrated parameter ensemble and its performance from this previous study are compared with a calibrated parameter ensemble of the model TRIGRS for the Passeier valley in South Tyrol, Italy. The comparison showed very similar model performance and large similarities in the calibrated geotechnical parameter values of the best model runs in both study areas. There is a subset of calibrated geotechnical parameter values that can be used successfully in both study areas and potentially other study areas with similar lithological characteristics. For the hydraulic parameters, the study did not find a transferable parameter subset. These parameters seem to be more sensitive to different soil types. Additionally, the results of the study also showed the importance of the inclusion of detailed information on the timing of landslide initiation in the calibration of the model.  相似文献   
239.
Summary Pre-Variscan basement in southern Poland is poorly exposed and thus known mostly from subsurface data. The availability of the latter is reviewed for terrains located between the Sudetes and the East European Platform. In these terrains the following relationships have been documented: Cadomian granitoids capped by Variscan flysch, Palaeozoic platform strata, Palaeozic folded and partly thermally altered successions, and low-grade metamorphic rocks overlain by Middle Cambrian strata. In view of their interrelationships the location of the Avalonia-Baltica suture in southeastern Poland is uncertain.  相似文献   
240.
Dissolved and particulate organic matter (DOM and POM) distribution, lignin phenol signatures, bulk elemental compositions, fluorescence indices and microbial plankton (algae, bacteria, viruses) in a temperate river floodplain system were monitored from January to November 2003. We aimed to elucidate the sources and compositions of allochthonous and autochthonous organic matter (OM) in the main channel and a representative backwater in relation to the hydrological regime. Additionally, bacterial secondary production was measured to evaluate the impact of organic carbon source on heterotrophic prokaryotic productivity. OM properties in the backwater tended to diverge from those in the main channel during phases without surface water connectivity; this was likely enhanced due to the exceptionally low river discharge in 2003. The terrestrial OM in this river floodplain system was largely derived from angiosperm leaves and grasses, as indicated by the lignin phenol composition. The lignin signatures exhibited significant seasonal changes, comparable to the seasonality of plankton-derived material. Microbially-derived material contributed significantly to POM and DOM, especially during periods of low discharge. High rates of bacterial secondary production (up to 135 μg C L(-1) d(-1)) followed algal blooms and suggested that autochthonous OM significantly supported heterotrophic microbial productivity.  相似文献   
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