Study of the Interaction Mechanism in the Biosorption of Copper(II) Ions onto Posidonia oceanica and Peat

A systematic approach was used to characterize the biosorption of copper(II) onto two biosorbents, Posidonia oceanica and peat, focusing on the interaction mechanisms, the copper(II) sorption–desorption process and the thermal behavior of the biosorbents. Sorption isotherms at pH 4–6 were obtained and the experimental data were fitted to the Langmuir model with a maximum uptake (q_max) at pH 6 of 85.78 and 49.69 mg g^?1, for P. oceanica and peat, respectively. A sequential desorption (SD) with water, Ca(NO₃)₂, and EDTA was applied to copper‐saturated biosorbents. Around 65–70% copper(II) were desorbed with EDTA, indicating that this heavy metal was strongly bound. The reversibility of copper(II) sorption was obtained by desorption with HCl and SD. Fourier transform IR spectroscopy (FTIR) analysis detected the presence of peaks associated with OH groups in aromatic and aliphatic structures, CH, CH₂, and CH₃ in aliphatic structures, COO^? and COOH groups and unsaturated aromatic structures on the surface of both biosorbents, as well as peaks corresponding to Si? O groups on the surface of peat. The results of SEM‐EDX and FTIR analysis of copper‐saturated samples demonstrated that ion exchange was one of the mechanisms involved in copper(II) retention. Thermal analysis of biosorbent samples showed that copper(II) sorption–desorption processes affected the thermal stability of the biosorbents.     

Comparing models of debris-flow susceptibility in the alpine environment

Debris-flows are widespread in Val di Fassa (Trento Province, Eastern Italian Alps) where they constitute one of the most dangerous gravity-induced surface processes. From a large set of environmental characteristics and a detailed inventory of debris flows, we developed five models to predict location of debris-flow source areas. The models differ in approach (statistical vs. physically-based) and type of terrain unit of reference (slope unit vs. grid cell). In the statistical models, a mix of several environmental factors classified areas with different debris-flow susceptibility; however, the factors that exert a strong discriminant power reduce to conditions of high slope-gradient, pasture or no vegetation cover, availability of detrital material, and active erosional processes. Since slope and land use are also used in the physically-based approach, all model results are largely controlled by the same leading variables.Overlaying susceptibility maps produced by the different methods (statistical vs. physically-based) for the same terrain unit of reference (grid cell) reveals a large difference, nearly 25% spatial mismatch. The spatial discrepancy exceeds 30% for susceptibility maps generated by the same method (discriminant analysis) but different terrain units (slope unit vs. grid cell). The size of the terrain unit also led to different susceptibility maps (almost 20% spatial mismatch). Maps based on different statistical tools (discriminant analysis vs. logistic regression) differed least (less than 10%). Hence, method and terrain unit proved to be equally important in mapping susceptibility.Model performance was evaluated from the percentages of terrain units that each model correctly classifies, the number of debris-flow falling within the area classified as unstable by each model, and through the metric of ROC curves. Although all techniques implemented yielded results essentially comparable; the discriminant model based on the partition of the study area into small slope units may constitute the most suitable approach to regional debris-flow assessment in the Alpine environment.     

Somma-Vesuvius’ activity: a mineral chemistry database

Mineralogy and Petrology - Clinopyroxene and olivine are ubiquitous phases in Somma-Vesuvius (SV) volcanics and for the first time they were systematically studied in several products younger than...     

Constraining Holocene sea levels using U‐Th ages of phreatic overgrowths on speleothems from coastal caves in Mallorca (Western Mediterranean)

Phreatic overgrowths on speleothems (POS) are carbonate formations deposited at the water table of caves in unique karstic coastal settings having morphologies that can be directly related to sea level at the time of formation. The U‐Th ages of calcite and aragonite overgrowths collected from the modern water table in coastal caves on Mallorca (Cova de Cala Varques A and Cova des Pas de Vallgornera) were determined using high‐precision MC‐ICPMS techniques. U‐Th ages indicate that phreatic carbonate deposition occurred between ca 2·8 and at least 0·6 ka BP and are in accord with an archeologically estimated age of 3·7–3·0 ka BP for a drowned prehistoric construction at a depth of 1 m below current sea level in a cave from the same area. Speleothem δ¹³C and δ¹⁸O and chemical composition of cave pools provide supportive evidence that POS reflect mixing between seawater and brackish water table. Copyright © 2010 John Wiley & Sons, Ltd.     

Steering of experimental channels by lateral basin tilting

A major issue in tectonics and sedimentation is the role of cross‐stream tectonic tilting in steering channels. The general idea is that channels will be attracted to lateral maxima in subsidence rate. A physical experiment performed in 1999 at the St. Anthony Falls Laboratory, however, was in conflict with the idea and showed that fluvial channels and resulting stratigraphy can be insensitive to even relatively strong lateral variation in subsidence. Here, we present results from an experiment which uses a simplified relay‐ramp geometry with laterally variable uplift and subsidence to test a hypothesis developed from the earlier experiment: Tectonic tilting steers channels only when the ratio of the time scales describing lateral channel mobility to tectonic deformation is sufficiently large. Occupation time by experimental channels and sand fraction in the deposit (a proxy for channel deposition) both increase with subsidence rate indicating strong steering of channels by tectonic forcing. We also found that, due to local incision, uplift lengthened the time scale for lateral channel migration relative to subsidence. Comparing channel mobility at the beginning of the experiment, with no tectonic forcing, to later tectonic stages of the experiment indicates that active tectonics increased the channel time scale. The interplay of channel steering with uplift and subsidence led to cyclic appearance and disappearance of an autogenic lake in the hanging‐wall basin. This lake was associated with alternation between channels going around vs. across the adjoining upstream uplifted footwall region. This creation and filling of the lake under constant tectonic forcing (constant fault slip rate) in the hanging wall created subaerial fan‐delta parasequences separated by fluvial deposits.     

Improved 2-D attenuation analysis for Northern Italy using a merged dataset from selected regional seismic networks

A merged, high-quality waveform dataset from different seismic networks has been used to improve our understanding of lateral seismic attenuation for Northern Italy. In a previous study on the same region, Morasca et al. (Bull Seismol Soc Am 98:1936–1946, 2008) were able to resolve only a small area due to limited data coverage. For this reason, the interpretation of the attenuation anomalies was difficult given the complexity of the region and the poor resolution of the available data. In order to better understand the lateral changes in the crustal structure and thickness of this region, we selected 770 earthquakes recorded by 54 stations for a total of almost 16,000 waveforms derived from seismic networks operating totally or partially in Northern Italy. Direct S-wave and coda attenuation images were obtained using an amplitude ratio technique that eliminates source terms from the formulation. Both direct and early-coda amplitudes are used as input for the inversions, and the results are compared. Results were obtained for various frequency bands ranging between 0.3 and 25.0 Hz and in all cases show significant improvement with respect to the previous study since the resolved area has been extended and more crossing paths have been used to image smaller scale anomalies. Quality-factor estimates are consistent with the regional tectonic structure exhibiting a general trend of low attenuation under the Po Plain basin and higher values for the Western Alps and Northern Apennines. The interpretation of the results for the Eastern Alps is not simple, possibly because our resolution for this area is still not adequate to resolve small-scale structures.     

The 12 May 1802 earthquake (N Italy) in its historical and seismological context

The Mw 5.7 earthquake that occurred on 12 May 1802 is the only one with Mw ≥ 5.5 located west of Lake Garda in the central-northern part of the Po Plain, Northern Italy, and the strongest event located in the seismic zone 907 of the ZS9 seismogenic zonation of Italy. Current parametric earthquake catalogs locate the event not far from important cities (e.g., Milan) and to sites where nuclear power plants were to be built in the 1980s or could be built in a near future. Although the earthquake parameters seemed sufficiently well constrained, a detailed investigation of documentary sources was performed, in repositories storing the documents of the Napoleonic departments to which the area affected by the earthquake belonged at that time. In the surviving archival series, we found the officers’ correspondence on all the administrative aspects raised by the earthquake. The newly collected records allowed the authors to significantly increase the number of macroseismic intensity data, including new observations in the most damaged area. The results have been then interpreted in terms of both Mercalli–Cancani–Sieberg and EMS98 macroseismic scales. The earthquake parameters were derived applying two different methods in order to get two independent estimates. Earthquake location is confirmed, although the still scarce data available in the area to the east of the epicenter do not permit to reduce the uncertainty to a minimum. According to the Boxer method, the magnitude is now slightly higher, and the source model shows a good agreement with the tectonic setting of the area.     

Reliability of the automatic procedures for locating earthquakes in southwestern Alps and northern Apennines (Italy)

Reliable automatic procedure for locating earthquake in quasi-real time is strongly needed for seismic warning system, earthquake preparedness, and producing shaking maps. The reliability of an automatic location algorithm is influenced by several factors such as errors in picking seismic phases, network geometry, and velocity model uncertainties. The main purpose of this work is to investigate the performances of different automatic procedures to choose the most suitable one to be applied for the quasi-real-time earthquake locations in northwestern Italy. The reliability of two automatic-picking algorithms (one based on the Characteristic Function (CF) analysis, CF picker, and the other one based on the Akaike’s information criterion (AIC), AIC picker) and two location methods (“Hypoellipse” and “NonLinLoc” codes) is analysed by comparing the automatically determined hypocentral coordinates with reference ones. Reference locations are computed by the “Hypoellipse” code considering manually revised data and tested using quarry blasts. The comparison is made on a dataset composed by 575 seismic events for the period 2000–2007 as recorded by the Regional Seismic network of Northwestern Italy. For P phases, similar results, in terms of both amount of detected picks and magnitude of travel time differences with respect to manual picks, are obtained applying the AIC and the CF picker; on the contrary, for S phases, the AIC picker seems to provide a significant greater number of readings than the CF picker. Furthermore, the “NonLinLoc” software (applied to a 3D velocity model) is proved to be more reliable than the “Hypoellipse” code (applied to layered 1D velocity models), leading to more reliable automatic locations also when outliers (wrong picks) are present.     

The Significance of Intestinal Parasite Remains in Pollen Samples from Medieval Pits in the Piazza Garibaldi of Parma,Emilia Romagna,Northern Italy

This paper presents the study of parasite remains recovered in pollen samples collected from archaeological layers. Laboratory treatment enabled us to obtain very high concentrations of both pollen and parasite eggs from the same samples. The case study of the site of Piazza Garibaldi in Parma, a town in the Po plain, is reported. The site was a sacred area in Roman times and a market square in Medieval times (10th–11th century A.D.). Pollen, seeds, and fruits from the latter phase were collected from four Medieval pits and one cesspit. After a palynological treatment including sieving, floating, and light acetolysis, abundant quantities of parasite eggs were extracted. Human and animal parasite eggs belonging to Trichuris, Ascaris, Taenia/Echinococcus, Capillaria, Dicrocoelium, and Diphyllobothrium were found. The analyses of animal and plant remains identified in the same samples suggested that the pit infillings consisted of waste, human and animal excrements, deteriorated plant food, and refuse of grapes. Therefore, parasite remains help the interpretation of archaeobotanical data in identifying human behaviors and site functions.     

Macroseismic effects highlight site response in Rome and its geological signature

A detailed analysis of the earthquake effects on the urban area of Rome has been conducted for the L??Aquila sequence, which occurred in April 2009, by using an online macroseismic questionnaire. Intensity residuals calculated using the mainshock and four aftershocks are analyzed in light of a very accurate and original geological reconstruction of the subsoil of Rome based on a large amount of wells. The aim of this work is to highlight ground motion amplification areas and to find a correlation with the geological settings at a subregional scale, putting in evidence the extreme complexity of the phenomenon and the difficulty of making a simplified model. Correlations between amplification areas and both near-surface and deep geology were found. Moreover, the detailed scale of investigation has permitted us to find a correlation between seismic amplification in recent alluvial settings and subsiding zones, and between heard seismic sound and Tiber alluvial sediments.