全文获取类型
收费全文 | 73篇 |
免费 | 3篇 |
专业分类
大气科学 | 6篇 |
地球物理 | 8篇 |
地质学 | 20篇 |
海洋学 | 38篇 |
天文学 | 1篇 |
自然地理 | 3篇 |
出版年
2021年 | 1篇 |
2020年 | 1篇 |
2019年 | 1篇 |
2018年 | 5篇 |
2017年 | 3篇 |
2016年 | 5篇 |
2015年 | 2篇 |
2013年 | 3篇 |
2012年 | 2篇 |
2011年 | 5篇 |
2010年 | 4篇 |
2009年 | 3篇 |
2008年 | 3篇 |
2007年 | 1篇 |
2006年 | 5篇 |
2005年 | 4篇 |
2003年 | 2篇 |
2002年 | 1篇 |
2000年 | 4篇 |
1999年 | 2篇 |
1998年 | 2篇 |
1997年 | 1篇 |
1996年 | 1篇 |
1992年 | 7篇 |
1991年 | 2篇 |
1985年 | 3篇 |
1984年 | 1篇 |
1983年 | 1篇 |
1976年 | 1篇 |
排序方式: 共有76条查询结果,搜索用时 0 毫秒
31.
The preliminary interpretation of new high-resolution seismic reflection profiles from the eastern Alboran Sea indicates strong geological similarities between this region and southeastern Spain. The principal neotectonic elements, which result from roughly north-south compression, are defined by northeast-southwest oriented wrenches separated by intervening north-south and west-northwest-east-southeast strike-slip faults. Variations in direction of principal stress axes have permitted faulting to alternate between these two systems, and for reverse faulting to occur within some wrench zones during periods when there was a component of compression perpendicular to them. 相似文献
32.
F. Gutiérrez-Santolalla M. Gutiérrez-Elorza C. Marín G. Desir C. Maldonado 《Environmental Geology》2005,48(3):360-369
A highly active collapse sinkhole field in the evaporitic mantled karst of the Ebro river valley is studied (NE Spain). The subsidence is controlled by a NW-SE trending joint system and accelerated by the discharge of waste water from a nearby industrial state. The morphometry, spatial distribution and temporal evolution of the sinkholes have been analysed. The volume of the sinkholes yields a minimum estimate of average lowering of the surface by collapse subsidence of 46 cm. The clustering of the sinkholes and the tendency to form elongated uvalas and linear belts, in a NW–SE direction have a predictive utility and allow the establishment of criteria for a hazard zonation. With the precipitation record supplied by a pluviograph and periodic cartographic and photographic surveys the influence of heavy rainfall events on the triggering of collapses has been studied. 相似文献
33.
Measurement of air temperature in the presence of a large radiant flux: an assessment of passively ventilated thermometer screens 总被引:1,自引:0,他引:1
Evyatar?ErellEmail author Vítor?Leal Eduardo?Maldonado 《Boundary-Layer Meteorology》2005,114(1):205-231
The energy balance of small temperature sensors was modelled to illustrate the effects of sensor characteristics, particularly size, on the accuracy of readings in the presence of strong shortwave or longwave radiant loads. For all but extremely small sensors, radiant exchange may lead to unacceptable errors. The common practice of using passively ventilated instrument screens was evaluated in a series of comparative measurements. The differences resulting from the use of different models of shields may be an order of magnitude greater than the error resulting from sensor calibration. In the absence of technological innovation capable of reducing the error due to radiant exchange to negligible proportions, it is suggested that a standard methodology for calibrating and labelling the error resulting from the characteristics of the screens be adopted, to allow comparison of new data with long-established records. 相似文献
34.
The northern Alboran Ridge margin depicts fault-bounded, structural blocks tilted downward to the basins. Post-Messinian sequences fill depressions on these blocks with thick depositional wedges thinning basinward. A change in the stress field after the Early Pliocene produced structural inversions and generalized uplifting of the Alboran Ridge from the Late Pliocene to Recent time. 相似文献
35.
Belén Alonso Kim A. Kastens Andrés Maldonado Alberto Malinverno C. Hans Nelson Suzanne O'Connell Alberto Palanques William B. F. Ryan 《Geo-Marine Letters》1985,5(3):141-148
The northern continental slope off the Ebro Delta has a badland topography indicating major slope erosion and mass movement of material that deposits sediment into a ponded lobe. The southern slope has a low degree of mass movement activity and slope valleys feed channel levee-complexes on a steep continental rise. The last active fan valley is V-shaped with little meandering and its thalweg merges downstream with the Valencia Valley. The older and larger inactive channel-levee complex is smoother, U-shaped, and meanders more than the active fan valley. 相似文献
36.
The western Alboran Sea contains three morphostructural domains: continental margins, structural highs, and basins, some with diapirs. Seven sequences from Tortonian to upper Quaternary, identified on airgun profiles, record a distinct set of depositional events. The tectonic evolution was influenced by the relative movement of the African and Iberian plates. Connections through the Atlantic/Mediterranean gateways and global sea level oscillations are recorded as major unconformities in the depositional record. A Neogene change in tectonic character from transtensional to transpressional regimes is postulated on the basis of changes in the regional stress field orientation. 相似文献
37.
David M. Semeniuk Jay T. Cullen W. Keith Johnson Katie Gagnon Thomas J. Ruth Maria T. Maldonado 《Deep Sea Research Part I: Oceanographic Research Papers》2009,56(7):1130-1142
We undertook the first measurements of metabolic Cu requirements (net Cu:C assimilation ratios) and steady-state Cu uptake rates (ρCuss) of natural plankton assemblages in the northeast subarctic Pacific using the short-lived radioisotope 67Cu. Size-fractionated net Cu:C assimilation ratios varied ~3 fold (1.35–4.21 μmol Cu mol C?1) among the stations along Line P, from high Fe coastal waters to the Fe-limited open ocean. The variability in Cu:C was comparable to biogenic Fe:C ratios in this region. As previously observed for Fe uptake, the bacterial size class accounted for half of the total particulate ρCuss. Interestingly, carbon biomass-normalized rates of Fe uptake from the siderophore desferrioxamine B (DFB) (ρFeDFB; a physiological proxy for Fe-limitation) by the >20 μm size class were positively correlated with the intracellular net Cu:C assimilation ratios in this size class, suggesting that intracellular Cu requirements for large phytoplankton respond to increased Fe-limitation. At Fe-limited Ocean Station Papa (OSP), we performed short-term Cu uptake (ρCuL) assays to determine the relative bioavailability of Cu bound to natural and synthetic ligands. Like the volumetric ρCuss measured along Line P, the bacterial size class was responsible for at least 50% of the total ρCuL. Uptake rates of Cu from the various organic complexes suggest that Cu uptake was controlled by the oxidation state of the metal and by the metal:ligand concentration ratio, rather than the concentration of inorganic species of Cu in solution. Collectively, these data suggest that Cu likely plays an important role in the physiology of natural plankton communities beyond the toxicological effects studied previously. 相似文献
38.
Ximena Aguilera Steven Declerck Luc De Meester Mabel Maldonado Frans Ollevier 《Limnologica》2006,36(4):258-268
Tropical high Andes lakes are aquatic ecosystems with peculiar limnological characteristics that are related to their geographical location and high altitude, yet they remained understudied. We present the results of a standardized survey of morphometric, physico-chemical and biotic variables in 32 high altitude lakes of the Cordillera del Tunari (Eastern Andes of Bolivia). Based on the variables measured, we identified three lake types. One group of lakes differed from the other lakes by a relatively high pH and biological productivity (as evidenced from higher densities of phytoplankton, zooplankton, and fish). A second group of lakes consisted of relatively large and deep water bodies with neutral to slightly acid pH and with a relatively high occurrence of the large cladoceran Daphnia pulex. The third group contained relatively small, shallow, and acid lakes with no Daphnia. Rainbow trout occurred in more than half of the lakes and catch yields were very variable. Overall, the abundances of different organism groups tended to be positively associated (e.g. phytoplankton, copepods, rotifers, fish) indicating the existence of a major productivity gradient. We found no negative associations between trout catches and densities of any of the major zooplankton groups, suggesting moderate to low top-down effects of trout on the zooplankton communities. 相似文献
39.
Balanyá J. C. Galindo-Zaldívar J. Jabaloy A. Leitchenkov G. Maldonado A. Rodríguez-Fernández J. Vinnikovskaya O. 《Geo-Marine Letters》1998,18(3):215-224
The structure of the South Powell Ridge (SPR), separating the Late Cenozoic ocean-floored Powell Basin and the Mesozoic Weddell Sea domain, is revealed by multichannel seismic data. The SPR appears as a basement high, bounded northward by transtensional faults and by normal and major reverse faults to the south. These margin features seem to be linked to the Powell Basin southern strike-slip margin and to the Jane Arc paleotrench, respectively. We suggest the ridge evolved from the Antarctic Peninsula passive margin to become the deformational front of the Scotia/Antarctica Plate boundary, later being welded to the Antarctic Plate.
相似文献40.
The impact of climate change on tribal communities in the US: displacement, relocation, and human rights 总被引:1,自引:1,他引:0
Julie Koppel Maldonado Christine Shearer Robin Bronen Kristina Peterson Heather Lazrus 《Climatic change》2013,120(3):601-614
Tribal communities in the United States, particularly in coastal areas, are being forced to relocate due to accelerated rates of sea level rise, land erosion, and/or permafrost thaw brought on by climate change. Forced relocation and inadequate governance mechanisms and budgets to address climate change and support adaptation strategies may cause loss of community and culture, health impacts, and economic decline, further exacerbating tribal impoverishment and injustice. Sovereign tribal communities around the US, however, are using creative strategies to counter these losses. Taking a human rights approach, this article looks at communities’ advocacy efforts and strategies in dealing with climate change, displacement, and relocation. Case studies of Coastal Alaska and Louisiana are included to consider how communities are shaping their own relocation efforts in line with their cultural practices and values. The article concludes with recommendations on steps for moving forward toward community-led and government-supported resettlement programs. 相似文献