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11.
The coastal plain of the Río de la Plata constitutes a large wetland which develops on the right margin of the river estuary. Anthropic activities such as intensive exploitation of groundwater carried out in the vicinity of the wetland can modify the natural hydrological regime. The aim of this work is to asses the effects of intensive aquifer exploitation in coastal wetlands using hydrogeological models. Such models allow to evaluate changes in the environmental conditions of wetland at regional level. The hydrogeological model exposed in this work shows how the intensive groundwater exploitation affects the wetland area, generating important variations both in the groundwater flows and in the salinity of the groundwater. Identification of these modifications to the environment is important to generate guidelines leading to minimize these affectations. 相似文献
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Geomorphologic map of the 1<Superscript>st</Superscript> Mutnaya River,Southeastern Kamchatka,Russia
Gheorghe Romanescu Sergey Chalov Cristian Constantin Stoleriu Alin Mihu-Pintilie Silvia Eleonora Angileri Yulia Kuznetsova Mariaelena Cama Michael Maerker 《山地科学学报》2017,14(12):2373-2390
The Kamchatka Peninsula–situated in the Pacific “Ring of Fire”–has 29 active and over 400 extinct volcanoes. Since it is situated in the northeastern extremity of Russia, in subarctic climate, the volcanic landforms are overprinted by the 446 glaciers. This research focuses on the 1stMutnaya catchment which drains the southern slopes of two active volcanoes: Avachinsky and Koryaksky. Those volcanoes are a permanent threat for the cities of Petropavlovsk and Elizovo, which are the 2 of 3 cities of the peninsula. Hence, most of the studies carried out in the area dealt with the natural hazards and only few focus on landscape evolution. Thus, the purpose of this study was to elaborate a cartographic approach which integrates classic geomorphology with state of the art GIS and remote sensing techniques. As result, different landforms and related processes have been analysed and included in the first general geomorphologic map of the 1stMutnaya catchment. 相似文献
14.
Alessandro Corsini Cristina Castagnetti Eleonora Bertacchini Riccardo Rivola Francesco Ronchetti Alessandro Capra 《地球表面变化过程与地形》2013,38(11):1330-1338
A slow moving compound rock slide located in the northern Apennines of Italy was mapped and monitored through the integration of Airborne Laser Scanning (ALS), multi‐temporal long‐range Terrestrial Laser Scanning (TLS), and Automated Total Station (ATS) measurements. Landslide features were mapped using a High Resolution Digital Terrain Model (HR‐DTM) obtained by merging ALS and TLS data in an Iterative Closest Point (ICP) procedure. Slope movements in the order of centimeters to a few decimeters were quantified with Differential TLS (D‐TLS) based on a Surface Matching approach and supported by ATS data to define stable reference surfaces. The integrated approach allowed mapping of the composite geomorphic features of the rock slide under examination, revealing its complex dynamic nature and further proving that laser scanning is a versatile and widely applicable tool for slope process analysis. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
15.
Sabino R Veríssimo C Cunha MA Wergikoski B Ferreira FC Rodrigues R Parada H Falcão L Rosado L Pinheiro C Paixão E Brandão J 《Marine pollution bulletin》2011,62(7):1506-1511
Whilst the potential impact on beach users from microorganisms in water has received considerable attention, there has been relatively little investigation into microbial contaminants in sand. Thirty three beaches across Portugal were analyzed during a five year period (2006-2010) to determine the presence of yeasts, pathogenic fungi, dermatophytes, total coliforms, Escherichia coli and intestinal enterococci in sand.Our results showed that 60.4% of the samples were positive for fungi and that 25.2% were positive for the bacterial parameters. The most frequent fungal species found were Candida sp. and Aspergillus sp., whereas intestinal enterococci were the most frequently isolated bacteria. Positive associations were detected among analyzed parameters and country-regions but none among those parameters and sampling period.Regarding threshold values, we propose 15 cfu/g for yeasts, 17 cfu/g for potential pathogenic fungi, 8 cfu/g for dermatophytes. Eighty four cfu/g for coliforms, 250 cfu/g for E. coli, and 100 cfu/g for intestinal enterococci. 相似文献
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Harry Y. McSween Jr. Richard P. Binzel M. Cristina De Sanctis Eleonora Ammannito Thomas H. Prettyman Andrew W. Beck Vishnu Reddy Lucille Le Corre Michael J. Gaffey Thomas B. McCord Carol A. Raymond Christopher T. Russell the Dawn Science Team 《Meteoritics & planetary science》2013,48(11):2090-2104
The Dawn mission has provided new evidence strengthening the identification of asteroid Vesta as the parent body of the howardite, eucrite, and diogenite (HED) meteorites. The evidence includes Vesta's petrologic complexity, detailed spectroscopic characteristics, unique space weathering, diagnostic geochemical abundances and neutron absorption characteristics, chronology of surface units and impact history, occurrence of exogenous carbonaceous chondritic materials in the regolith, and dimensions of the core, all of which are consistent with HED observations and constraints. Global mapping of the distributions of HED lithologies by Dawn cameras and spectrometers provides the missing geologic context for these meteorites, thereby allowing tests of petrogenetic models and increasing their scientific value. 相似文献
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Mucerino Luigi Carpi Luca Schiaffino Chiara F. Pranzini Enzo Sessa Eleonora Ferrari Marco 《Natural Hazards》2021,105(1):137-156
Natural Hazards - Rip currents are one of the most significant environmental hazards for beachgoers and are of interest to coastal scientists. Several studies have been conducted to understand rip... 相似文献
19.
Martino Amodio Eleonora Andriani Maurizio Caselli Paolo R. Dambruoso Barbara E. Daresta Gianluigi de Gennaro Pierina Ielpo Claudia M. Placentino Maria Tutino 《Journal of Atmospheric Chemistry》2009,63(3):203-220
The chemical composition of PM10 and PM2.5 samples collected during two seasonal monitoring campaigns at residential, urban and industrial Apulia Region- sites was
investigated. Ionic fraction, carbonaceous compounds and Polycyclic Aromatic Hydrocarbons were determined for all samples.
High correlations among PM data collected in the investigated sites suggested the regional character of particulate matter.
It was also confirmed by five days back trajectories analysis. Moreover, no significant seasonal trend in PM mass concentration
was observed in the investigated sites. These results, relevant for the area under investigations, were not observed in the
North of Italy and Europe and allow to conclude that PM10 and PM2.5 cannot be considered ‘good’ indicators for the evaluation of local anthropic contributions to air quality. On the contrary,
the high levels of Polycyclic Aromatic Hydrocarbons found in Taranto sampling sites suggested that PAHs can be a better indicator
for this purpose. This result is also relevant in order to weigh the importance of industrial area and to suggest right policy
control to decision makers. 相似文献
20.
Acceleration of buoyancy-driven fractures and magmatic dikes beneath the free surface 总被引:3,自引:0,他引:3
By performing buoyancy-driven fracture experiments in brittle gelatin we observe that the ascent velocity of a fracture containing a finite volume of fluid increases when approaching the free surface. We theoretically describe this free-surface effect and quantify it by introducing an effective depth-dependent fracture toughness and developing an ascent model on the basis of linear fracture mechanics. We develop a successful inversion approach and resolve the actual and critical fracture length and the ascent velocity far away from the free surface from the observation of the fracture tip migration alone. Other parameters, as the fluid volume included in the fracture and the in situ fracture toughness, can be derived. Applying the model and inversion to the 1998 eruption at Piton de la Fournaise, Reunion Island, reveals estimates of the length and critical length of the feeding magma batch, the magma batch volume and the in situ fracture toughness. It further indicates that the ascent velocity of the magma batch was probably much smaller at greater depths and that the batch might have been initiated several months or years before the eruption. 相似文献