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Simone Fiaschi Serena Tessitore Roberta Bonì Diego Di Martire Vladimiro Achilli Sven Borgstrom 《地理信息系统科学与遥感》2017,54(3):305-328
Land subsidence due to underground resources exploitation is a well-known problem that affects many cities in the world, especially the ones located along the coastal areas where the combined effect of subsidence and sea level rise increases the flooding risk. In this study, 25 years of land subsidence affecting the Municipality of Ravenna (Italy) are monitored using Advanced Differential Interferometric Synthetic Aperture Radar (A-DInSAR) techniques. In particular, the exploitation of the new Sentinel-1A SAR data allowed us to extend the monitoring period till 2016, giving a better understanding of the temporal evolution of the phenomenon in the area. Two statistical approaches are applied to fully exploit the informative potential of the A-DInSAR results in a fast and systematic way. Thanks to the applied analyses, we described the behavior of the subsidence during the monitored period along with the relationship between the occurrence of the displacement and its main driving factors. 相似文献
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Time-dependent evaporation of icy mantles in hot cores 总被引:1,自引:0,他引:1
Serena Viti David A. Williams 《Monthly notices of the Royal Astronomical Society》1999,305(4):755-762
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Serena Love 《Geoarchaeology》2012,27(2):140-156
This article provides a methodology for extracting social information through an analysis of mudbrick compositions, using a case study from Çatalhöyük, Turkey. Particle size analysis, loss on ignition, and magnetic susceptibility were used to examine variability in mudbrick recipe. The analysis revealed that neither magnetic susceptibility nor calcium carbonate were significantly altered through tempering. The results suggest that the greatest degree of compositional variability was a result of the manufacture process and not raw materials used in production. Mudbricks are products of deliberate human actions, similar to any other artifact assemblage, but have been long overlooked. Examining the technology involved with mudbrick manufacture highlights aspects of Neolithic social life through shared resources, production choices, and organization of labor. The analysis of mudbrick compositions considers how raw materials were used within and between groups of houses, represented in 1000 years of uninterrupted occupation at Çatalhöyük. 相似文献
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Geochemistry and quality of the groundwater from the karstic and coastal aquifer of Geropotamos River Basin at north-central Crete, Greece 总被引:2,自引:2,他引:0
Francesco Sdao Serena Parisi Despina Kalisperi Stefania Pascale Pantelis Soupios Nikos Lydakis-Simantiris Maria Kouli 《Environmental Earth Sciences》2012,67(4):1145-1153
In Geropotamos River Basin, located on the north-central part of Crete, Greece, two main factors were believed to be affecting the geochemistry of the groundwater with high salt contents: seawater intrusion and/or Miocene evaporates. To identify the origin of the high salinity in groundwater, a hydrogeochemical and isotopic study was performed. Water samples from 22 wells and 2 springs were analyzed for physico-chemical parameters, major ions analysis, as well as stable isotopes (??18O, ??D). From the present survey, in which detailed hydrogeochemical investigation was conducted, the uncertainty of the contamination sources was decreased in the northern part of Geropotamos Basin. The results complement the scenario in which seawater and the widespread human activities are the principal sources of groundwater contamination. Moreover, the results of the stable isotopes analyses (??18O and ??D) support the same hypothesis and make seawater intrusion the most probable cause for the highest salinity waters. It is indicated that saline intrusion is likely to occur along fractures in a fault zone through otherwise low-permeability phyllite?Cquartzite bedrock, which demonstrates the critical role of fracture pathways in salination problems of coastal aquifers. 相似文献
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C. J. Lintott S. Viti D. A. Williams J. M. C. Rawlings I. Ferreras 《Monthly notices of the Royal Astronomical Society》2005,360(4):1527-1531
The very high rates of second generation star formation detected and inferred in high-redshift objects should be accompanied by intense millimetre-wave emission from hot core molecules. We calculate the molecular abundances likely to arise in hot cores associated with massive star formation at high redshift, using several different models of metallicity in the early Universe. If the number of hot cores exceeds that in the Milky Way Galaxy by a factor of at least 1000, then a wide range of molecules in high-redshift hot cores should have detectable emission. It should be possible to distinguish between different models for the production of metals and hence hot core molecules should be useful probes of star formation at high redshift. 相似文献
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Patricija Mozetič Cosimo Solidoro Gianpiero Cossarini Giorgio Socal Robert Precali Janja Francé Franco Bianchi Cinzia De Vittor Nenad Smodlaka Serena Fonda Umani 《Estuaries and Coasts》2010,33(2):362-375
The results of the updated and quality-checked data base of field observations on chlorophyll a (Chl a) collected in the period 1970–2007 in the Northern Adriatic Sea are presented. From the last decade, SeaWiFS satellite information
was also considered. Results demonstrate a global tendency towards Chl a reduction in the period of investigation, which is more marked in the eutrophic area under the influence of the Po River.
In the rest of the basin, which presents meso- or oligotrophic characteristics, long-term changes are more difficult to detect.
The long-term field dataset can be divided into two periods: the last decade characterized by the strong decrease observed
in the whole northern Adriatic and the earlier period with no or slight increase. The recent substantial reduction of Chl
a concentrations is confirmed all over the basin (−0.11 mg m−3 year−1) from satellite-derived information. Results are consistent with recently evidenced decrease in concentrations of phosphate
and ammonia and point to the existence of oligotrophication in the Northern Adriatic. Results indicate forcefully that the
still common perception of the Adriatic Sea as a very eutrophic basin is no longer appropriate, at least for its northern
part and in recent years. 相似文献