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131.
Landfalling tropical cyclones often produce tornadoes. This study investigates how hazardous these tornadoes are to human
life by analyzing the resultant casualties, which includes fatalities and injuries. From 1995 to 2009, 63 tropical cyclones
made landfall in the United States producing a reported 1,139 tornadoes. Most tornadoes resulted in no casualties but a few
extreme cases indicate that the potential exists for a substantial number of casualties. Temporal and spatial analyses indicate
that most casualties occur when and where the physical risk of tornadoes is elevated. 相似文献
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133.
Early Cretaceous exhumation of the Qiangtang Terrane during collision with the Lhasa Terrane,Central Tibet 总被引:1,自引:0,他引:1
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The timing of the closure of the Bangong Ocean between the Lhasa and South Qiangtang Terranes in central Tibet and the resulting crustal thickening are still under debate. We integrate published apatite fission track and (U–Th)/He thermochronometer data with new zircon (U–Th)/He ages from eight samples and with structural profiles to document that the South Qiangtang Terrane experienced slow exhumation between 200 and 150 Ma, associated with the opening of the Bangong Ocean. Accelerated exhumation (around 0.2–0.3 mm/a) of the South Qiangtang Terrane was initiated at around 150 Ma. This exhumation event is interpreted to reflect collision between the Lhasa and South Qiangtang Terranes after closure of the Bangong Ocean, associated with crustal thickening via thick‐skinned folding and thrusting within the South Qiangtang Terrane. The amalgamation of the Lhasa and South Qiangtang Terranes recorded here may represent the first stage of crustal thickening in the central Tibetan Plateau. 相似文献
134.
W. Todd Jarvis 《Ground water》2010,48(3):346-350
135.
Predicting phosphorus dynamics in complex terrains using a variable source area hydrology model
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Amy S. Collick Daniel R. Fuka Peter J. A. Kleinman Anthony R. Buda Jennifer L. Weld Mike J. White Tamie L. Veith Ray B. Bryant Carl H. Bolster Zachary M. Easton 《水文研究》2015,29(4):588-601
Phosphorus (P) loss from agricultural watersheds has long been a critical water quality problem, the control of which has been the focus of considerable research and investment. Preventing P loss depends on accurately representing the hydrological and chemical processes governing P mobilization and transport. The Soil and Water Assessment Tool (SWAT) is a watershed model commonly used to predict run‐off and non‐point source pollution transport. SWAT simulates run‐off employing either the curve number (CN) or the Green and Ampt methods, both assume infiltration‐excess run‐off, although shallow soils underlain by a restricting layer commonly generate saturation‐excess run‐off from variable source areas (VSA). In this study, we compared traditional SWAT with a re‐conceptualized version, SWAT‐VSA, that represents VSA hydrology, in a complex agricultural watershed in east central Pennsylvania. The objectives of this research were to provide further evidence of SWAT‐VSA's integrated and distributed predictive capabilities against measured surface run‐off and stream P loads and to highlight the model's ability to drive sub‐field management of P. Thus, we relied on a detailed field management database to parameterize the models. SWAT and SWAT‐VSA predicted discharge similarly well (daily Nash–Sutcliffe efficiencies of 0.61 and 0.66, respectively), but SWAT‐VSA outperformed SWAT in predicting P export from the watershed. SWAT estimated lower P loss (0.0–0.25 kg ha?1) from agricultural fields than SWAT‐VSA (0.0–1.0+ kg ha?1), which also identified critical source areas – those areas generating large run‐off and P losses at the sub‐field level. These results support the use of SWAT‐VSA in predicting watershed‐scale P losses and identifying critical source areas of P loss in landscapes with VSA hydrology. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
136.
Stephen T. Ross W. Todd Slack Ryan J. Heise Mark A. Dugo Howard Rogillio Bryant R. Bowen Paul Mickle Richard W. Heard 《Estuaries and Coasts》2009,32(2):360-374
Gulf sturgeon are anadromous, spawning in freshwater and returning to the marine environment to feed. Herein, we document
the marine distribution and timing of movement in and out of the marine environment of Gulf sturgeon natal to the Pascagoula
and Pearl rivers (MS and LA). From 1999 to 2004, we attached sonic transmitters to 194 fish averaging 151 (MS) to 160 (LA)
cm in fork length. We located 56 different Gulf sturgeon in the estuarine or marine environments, some multiple times. Fish
were distributed nonrandomly, being found primarily in shallow water (mean = 3.9 m) in barrier island passes. Benthic samples
taken at Gulf sturgeon telemetry location sites were dominated by Florida lancelets, sand dollars, annelids, haustoriid amphipods,
and mollusks—all documented prey of Gulf sturgeon. Movement into salt water consistently occurred in October and November;
movement back into rivers or low salinity estuaries was complete by the end of March. 相似文献
137.
138.
Adams J Houde M Muir D Speakman T Bossart G Fair P 《Marine environmental research》2008,66(4):430-437
The distribution of perfluoroalkyl compounds (PFCs) in the environment is well documented with higher concentrations observed in wildlife located in industrial and urban areas. This study examined the distribution of PFCs in relation to land use using blood samples collected from bottlenose dolphins during capture-release health assessment surveys conducted in Charleston, SC. The study area was partitioned into three subareas (ACW, CHS, and SRE) based upon habitat and land use characteristics. The ACW and CHS subareas are characterized by high degrees of industrial and urban land uses, while the SRE subarea is more residential and characterized by a lower degree of developed land use. Long-term monitoring data from photo-identification surveys were used to group bottlenose dolphins based on their proportions of sightings in the different subareas. Dolphins affiliated with both the ACW and CHS subareas were observed to have significantly higher mean plasma concentrations of perfluorooctane sulfonate (PFOS), perfluorodecanoic acid (PFDA) and perfluoroundecanoic acid (PFUnA) than those affiliated with the SRE subarea. Dolphins affiliated with the ACW subarea were found to have a significantly higher mean plasma concentration of PFUnA than those affiliated with the CHS subarea. Further examination of the distribution of the PFCs revealed positive correlations with developed land uses and negative correlations with wetland/marsh land cover. A positive correlation was also observed between PFUnA and agricultural land use. The variability and scale of the observed contaminant burdens have important implications for the conservation and management of living marine resources and illustrates the importance of long-term monitoring of free-ranging wildlife species. 相似文献
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140.