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The oceanographic forecast capability in coastal seas is often limited by the capacity of the numerical models in correctly reproducing the complex morphology of the coastline and the exchange processes between the shelf and the open seas. In the marginal Adriatic Sea this task is of uppermost importance due to the presence of several coastal water bodies and rivers. We present here a new oceanographic system, based on the unstructured grid model SHYFEM and representingthe whole Adriatic Sea together with the lagoons of Marano-Grado, Venice and Po Delta. The innovative aspect of the oceanographic system for the Adriatic Sea presented in this study is that it accurately addresses land-sea, air-sea, and coastal-offshore interactions. These processes are taken into account in the forecasting system by adopting adjourned discharge for most of the rivers, by forcing the hydrodynamic model with high-resolution meteorological fields, and by resolving the lagoon-sea and the river-sea continuum using a very high-resolution, up to 10 m, numerical mesh. The presented results highlighted the capacity of the developed system in simulating the general circulation in the Adriatic Sea, as well as several relevant coastal dynamics, such as tidal dynamics, saltwater intrusion, storm surge and riverine waters dispersion.

Il Disciplinare Tecnico dello Studio B.6.72 B/12, come i precedenti, ha previsto specifiche attività per il monitoraggio dei parametri diretti, cioè di quei parametri per i quali esiste una relazione sufficientemente chiara di causa-effetto tra disturbo generato dalle attività di cantiere e impatto prodotto e che possono evidenziare rapidamente una situazione di stress. Tra i parametri diretti è stata considerata la torbidità generata dalle operazioni di dragaggio. Le attività alle 3 bocche di porto vengono intese sia come monitoraggio della torbidità prodotta direttamente dalle attività di cantiere (monitoraggio alla sorgente, in periodi prestabiliti al fine di caratterizzare le diverse condizioni operative del cantiere e analisi granulometriche del particellato) sia come caratterizzazione del particellato sospeso (valutazione "mediata" del trasporto solido alle bocche, con misurazioni in continuo al fine di valutare il trasporto solido operato dai cicli di marea). Le attività di monitoraggio oggetto del presente studio sono sostanzialmente una prosecuzione per il periodo maggio 2016 - aprile 2017 delle attività di monitoraggio degli studi precedenti B.6.72 B/1 - B/11.

Context. The Gaia-ESO Survey (GES) is a large spectroscopic survey that provides a unique opportunity to study the distribution of spectroscopic multiple systems among different populations of the Galaxy. Aims. Our aim is to detect binarity/multiplicity for stars targeted by the GES from the analysis of the cross-correlation functions (CCFs) of the GES spectra with spectral templates. Methods. We developed a method based on the computation of the CCF successive derivatives to detect multiple peaks and determine their radial velocities, even when the peaks are strongly blended. The parameters of the detection of extrema (doe) code have been optimized for each GES GIRAFFE and UVES setup to maximize detection. The doe code therefore allows to automatically detect multiple line spectroscopic binaries (SBn, n ≥ 2). Results. We apply this method on the fourth GES internal data release and detect 354 SBn candidates (342 SB2, 11 SB3, and even one SB4), including only nine SBs known in the literature. This implies that about 98% of these SBn candidates are new because of their faint visual magnitude that can reach V = 19. Visual inspection of the SBn candidate spectra reveals that the most probable candidates have indeed a composite spectrum. Among the SB2 candidates, an orbital solution could be computed for two previously unknown binaries: CNAME 06404608+0949173 (known as V642 Mon) in NGC 2264 and CNAME 19013257-0027338 in Berkeley 81 (Be 81). A detailed analysis of the unique SB4 (four peaks in the CCF) reveals that CNAME 08414659-5303449 (HD 74438) in the open cluster IC 2391 is a physically bound stellar quadruple system. The SB candidates belonging to stellar clusters are reviewed in detail to discard false detections. We suggest that atmospheric parameters should not be used for these system components; SB-specific pipelines should be used instead. Conclusions. Our implementation of an automatic detection of spectroscopic binaries within the GES has allowed the efficient discovery of many new multiple systems. With the detection of the SB1 candidates that will be the subject of a forthcoming paper, the study of the statistical and physical properties of the spectroscopic multiple systems will soon be possible for the entire GES sample. © ESO 2017.

per il monitoraggio dei parametri diretti, cioè di quei parametri per i quali esiste una relazione sufficientemente immediata di causa-effetto tra disturbo generato dalle attività di cantiere e impatto prodotto e che possono evidenziare rapidamente una situazione di stress. Tra i parametri diretti è stata considerata la torbidità generata dalle operazioni di dragaggio. Le attività alle 3 bocche di porto vengono intese come monitoraggio della torbidità prodotta direttamente dalle attività di cantiere (monitoraggio alla sorgente, in periodi prestabiliti al fine di caratterizzare le diverse condizioni operative del cantiere e analisi granulometriche del particellato). Le attività di monitoraggio oggetto del presente studio sono sostanzialmente una prosecuzione per il periodo Maggio 2015 - Aprile 2016 delle attività di monitoraggio degli studi B.6.72 B/1 - B/10.

Le attività di monitoraggio oggetto del presente studio sono sostanzialmente una prosecuzione per ulteriori 12 mesi (maggio 2014 - aprile 2015) delle attività di monitoraggio degli studi precedenti B.6.72 B/1 - B/9. Il Disciplinare Tecnico dello Studio B.6.72 B/10, come i precedenti, ha previsto specifiche attività per il monitoraggio dei parametri diretti, cioè di quei parametri per i quali esiste una relazione sufficientemente chiara di causa-effetto tra disturbo generato dalle attività di cantiere e impatto prodotto e che possono evidenziare rapidamente una situazione di stress. Tra i parametri diretti è stata considerata la torbidità generata dalle operazioni di dragaggio. Le attività alle 3 bocche di porto vengono intese sia come monitoraggio della torbidità prodotta direttamente dalle attività di cantiere (monitoraggio alla sorgente, in periodi prestabiliti al fine di caratterizzare le diverse condizioni operative del cantiere e analisi granulometriche del particellato) sia come caratterizzazione del particellato sospeso (valutazione "mediata" del trasporto solido alle bocche, con misurazioni in continuo al fine di valutare il trasporto solido operato dai cicli di marea).

Le attività di monitoraggio oggetto del presente studio sono sostanzialmente una prosecuzione per ulteriori 12 mesi (maggio 2013 - aprile 2014) delle attività di monitoraggio degli studi precedenti B.6.72 B/1 - B/8. Il Disciplinare Tecnico dello Studio B.6.72 B/9, come i precedenti, ha previsto specifiche attività per il monitoraggio dei parametri diretti, cioè di quei parametri per i quali esiste una relazione sufficientemente chiara di causa-effetto tra disturbo generato dalle attività di cantiere e impatto prodotto e che possono evidenziare rapidamente una situazione di stress. Tra i parametri diretti è stata considerata la torbidità generata dalle operazioni di dragaggio. Le attività alle 3 bocche di porto vengono intese sia come monitoraggio della torbidità prodotta direttamente dalle attività di cantiere (monitoraggio alla sorgente, in periodi prestabiliti al fine di caratterizzare le diverse condizioni operative del cantiere e analisi granulometriche del particellato) sia come caratterizzazione del particellato sospeso (valutazione "mediata" del trasporto solido alle bocche, con misurazioni in continuo al fine di valutare il trasporto solido operato dai cicli di marea).

The results of an investigation about the heavy-metal distribution in pore waters of an estuarine shallow-water system (Cona Marsh, Venice Lagoon) are described. The area was sampled for surface and subsurface sediments; pore waters were extracted by centrifugation and heavy-metal concentration measured by means of PIXE technique. A high variability of heavy-metal concentration was observed in pore waters of sampled sites, as a result of physico-chemical conditions in the water sediment column, with a different spatial distribution between two groups of metals (Fe, Mn and Crvs. Cu, Ni and Zn). Concentration gradients between pore and bottom waters were evaluated in order to investigate the metal enrichment as a function of their mobility in the sediment and diagenesis phenomena.

The article describes the methodology developed for the monitoring program of the turbidity created by the recent operations in the 3 inlets of the Lagoon of Venice. The article is organized in three parts: (a) the experimental procedure (by means of fixed and boat-mounted instruments) and the determination of the turbidity's threshold-value; (b) the mathematical model applied for simulating the functioning of a trailing suction hopper dredger and the dynamics of the turbidity plume; (c) the continuous data turbidity (3 years) in the three inlets and the nearby littorals, with some interpretation regarding the net long-term fluxes, from the lagoon.

As a part of a future plan for regional management of river and sea sediments, we want to search alternative methods for measuring and predicting the quantity of sediments conveyed by the rivers flowing directly in the Lagoon of Venice and also to understand what types of measurements may be useful in the future study. Starting from a formulation of the sediment transport of rivers in Equilibrium conditions, the University of Padua has developed a model that, after appropriate calibration, is able to reproduce and reasonably predict the instantaneous sediment transport of a river even in non-equilibrium (Di Silvio et al., 2010). This model, initially developed for large rivers with different upperland watersheds, is meant to be applied in this more limited lowland context, however potentially richer in terms of experimental data.

Preliminary results of an investigation on trace metals behaviour in the estuarine system of the Dese River (Venice Lagoon) are described. Hydrodynamical and water chemical-physical measurements and PIXE concentrations analysis on size-fractionated samples emphasize the complexity of the processes occurring in the area of salt and fresh water mixing. Suspended load variations in the bottom layer of the water column, which may be mostly ascribed to resuspension, regulate the trace metal concentrations and seem to play a fundamental role in the transport of pollutants in shallow water areas of the estuary. The behaviour of dissolved metals is masked by the presence of suspended matter, but some relationships with chemical-physical variables are distinguishable, furnishing information on the processes affecting their concentration in the system.

The four naturally-occurring isotopes of radium were coupled with a previously evaluated hydrodynamic model to determine the apparent age of surface waters and to quantify submarine groundwater discharge (SGD) into the Venice Lagoon, Italy. Mean apparent age of water in the Venice Lagoon was calculated using the ratio of 224Ra to 228Ra determined from 30 monitoring stations and a mean pore water endmember. Average apparent age was calculated to be 6.0 d using Ra ratios. This calculated age was very similar to average residence time calculated for the same period using a hydrodynamic model (5.8 d). A mass balance of Ra was accomplished by quantifying each of the sources and sinks of Ra in the lagoon, with the unknown variable being attributed to SGD. Total SGD were calculated to be 4.1 ± 1.5, 3.8 ± 0.7, 3.0 ± 1.3, and 3.5 ± 1.0 × 1010 L d-1 for 223,224,226, 228Ra, respectively, which are an order of magnitude larger than total mean fluvial discharge into the Venice Lagoon (3.1 × 109 L d-1). The SGD as a source of nutrients in the Venice Lagoon is also discussed and, though significant to the nutrient budget, is likely to be less important as the dominant control on SGD is recirculated seawater rather than freshwater.

This contribution discusses the methodology and results of a research on sediment dynamics in the coastal areas close to the three inlets of the Venice Lagoon in normal (tide-governed) and storm conditions. The study, which is based on experimental investigations and mathematical models, attempts to improve the knowledge on suspended sediment transport along the littorals and its interactions with tidal exchanges at the inlets. The trend of littoral currents and the distribution of suspended particulate matter (SPM) along the coastline, which affect the solid fluxes through the inlets, have been investigated within specific field measurements by using Acoustic Doppler Current Profilers (ADCP). These instrument, mounted on a survey boat permit to acquire a bi-dimensional representation of the current field and backscatter. This last is related to the concentration of the scatterers (SPM) in the water column via calibration against concentration measured in water samples collected during the transect profiling. The modeling study apply an integrated 3-D model which permits to describe the dynamics of dispersion and transport of sediments. The considered numerical models, in increasing order of complexity are: a finite-elements hydrodynamical model (SHYFEM), a dispersion and diffusion module for contaminants, a finite-elements spectral wave model (WWM) and a sediment transport model (SEDTRANS05). The integrated experimental-modelling study permitted to investigate the effects of the modified morphology of the inlets on the velocity field induced by the tide. It also allowed a detailed study of sediment transport in the areas adjacent to the inlets during two storm events.

The activities of 224Ra isotope were measured in 30 pre-determined locations within the Venice Lagoon, Italy, during different seasons. These surveys were performed in order to determine both seasonal variation and average annual activity within the lagoon. The first survey was completed in the surnrner of2005, the other two surveys were accomplished in the fall of 2006 and winter of 2007. End-member samples were also collected in the Adriatic Sea and a couple of rivers. The concentration of 224Ra in the pore water is often 2 orders of magnitude higher than its subsequent concentration in the open sea. We hence utilize the measured activities of radium to determine both the relative magnitude and location of the groundwater discharging into the Venice Lagoon. In addition point measurements of discharge using vented benthic chambers were taken in several locations during the sampling period in order to corroborate the radium measurements. Both integrated and point measurements display a large discharge of groundwater occurring in the northern lagoon as well as certain places in the southern area. The local discharge may vary with time though the general pattern does not display significant change between seasons. Though most of the discharge is likely to be recirculated salt water of varying origins, previous data show that this discharge is of a very large volume as compared to the fluvial discharge (as much as 20 fold greater). The zone where groundwater mixes with salt water has been likened to processes occurring in an estuary, and here many important chernic!ll reactions can take place. In addition, groundwater is often elevated in the concentration of contaminants so its discharge to the lagoon can be a major source of contamination.

Two methods for conversion of the backscatter intensity provided by the bottom-mounted Acoustic Doppler Current Profiler (ADCP) situated in Lido inlet, and related results, are outlined in this paper. The time series of the backscatter intensity from the fixed ADCP is calibrated against the in situ data collected through the extensive series of field measurements. The two time series of concentration estimates are obtained; the former is based on water samples, and the latter on concentration estimates obtained from the calibration of the backscatter measured along transects acquired by a boat-mounted ADCP. The advantage of the first method is in using the concentration determined directly from the water samples, · but it describes the vertical profile with a scarce resolution. The second method provides finer vertical resolution, but includes the possible effects of the lateral gradients in the distribution of suspended particles in the investigated section. In majority of cases the differences between the two time series are low, and in 88 % of cases they are not higher than 40 %. The differences between the two become important during particularmenvironmental conditions, in general associated to the occurrence of particularly strong north-easterly (Bora) winds. It is well known that in such circumstances the wave motion generates resuspension of the bottom sediments, and causes erosion of the littoral adjacent to the Lido inlet. For the low wind conditions, the differences may occur during the ebb tidal flow of more than 0.5 m/s. The estimates of the sediment transport close to the bottom, which is predominantly constituted by fine and very fine sand, as demonstrated by recent investigations, significantly contributes to the accuracy of the fixed instrument time series. The future work will be focused on the integration of both contributes in the water column. This is fundamental in order to obtain an overall balance between the erosion and deposition in the Lido inlet.

Bacterial sulphate reduction is the predominant process in the cycling of organic matter and anthropogenic contaminants in permanently anoxic sediments such as those of the Venice canal network. Urban materials delivered to the canals and suspended particles transported by tidal currents from the open lagoon cause the silting up of the channel bed at a rate of 2 cm y-1, therefore requiring periodic dredging. As the recent maintenance interventions on canals are accompanied by the extensive improvement of the sewer system, there is an increasing interest for understanding how effective are natural processes in the metabolism of the large amount of organic matter accumulating in the sediment. A specific investigation on sulphate reduction was then started on May 2003. Sulphate reduction rates were measured, as sulphate depletion on incubated sample of the superficial sediment (0-5 cm), in 5 test canals. Measurements were repeated in July and October 2003, to investigate how the rates vary in response to temperature changes. If compared to typical values for estuary and salt marshes, rates measured are among the highest (up to 1.7 mmol l-1 d-1), the limiting factor being only the concentration of S2-. As expected, the highest rates were measured in summer (0.5-1. 7 mmol l-1 d-1). However, significant spatial differences were observable, particularly in the way each site responds to seasonal changes. We interpret major changes as the effect of a non-uniform distribution of bacterial population within the network sediments or a different diffusion of SO42- as a result of local changes in the aggregation state of the sediment. A simple first-order kinetic model applied to S042- concentrations measured in pore waters from 30 cm-long sediment cores finally permitted to better estimate the mean annual sulphate reduction rates which are consistent with values obtained by the incubation of surface sediments.

The backscatter signal recorded by the ADCP ('Acoustic Doppler Current Profiler'), and properly calibrated, has provided an estimation of the time variability of the suspended particulate matter (SPM) in the Malamocco inlet. Both the data from the ship-mounted ADCP and gravimetric data deriving from the water samples, collected during the campaign in January 2006, were used to determine the sediment concentration in the water column, above the bottom mounted ADCP, moored in the central part near the mouth of the inlet. Assuming that the relationship between the backscatter and the SPM concentration can be extended to a longer period, the calibration procedure was extrapolated for the time before and after the January campaign. Thus, the long term variability of the SPM concentration was obtained for the duration of four months (October 24, 2005 - February 21, 2006)., at the temporal and spatial resolutions of 10 minutes and 1 m, respectively. The evolution of a vertically averaged SPM concentration in the water column is depicted in Fig. 1, together with the vertically averaged axial current, and wind vector components. The currents are to a great extent tidally driven, with a prevalent semi-diurnal signal, whose range is modulated by a spring-neap cycle. Other long-term, non-tidal phenomena are of less influence. The concentration, on the contrary, shows a greater variability associated to the periods of strong winds, than to the tidal excursion. The wind influence plays a major role through the erosion induced by the waves. As observed, the analysed period is rich in strong wind events, particularly due to the bora (ENE wind). An additional aim of this study is to estimate the total SPM transport in the period of time across the inlet, on one hand, and, on the other hand, to derive a preliminary budget of the transport, in comparison with the other two inlets, Lido and Chioggia.

The fate of anthropogenic heavy metal in the contaminated anoxic sediments of the Venice canals is mainly conditioned by sulphidic transformations occurring during the early diagenesis. Bacterial sulphate reduction is the key process in the metabolism of organic matter supplied to the system by the untreated effluents directly discharged in the network. Based on our recent measurements of sulphate reduction rates in representative sites, an average of more than 500 kg d-1 of sulphate-S is converted into S 2- in the warm period (May-October). Part of the so formed S2- can diffuse across the sediment water-interface, being eventually released to the water column and readily oxidised. However, a considerable proportion of S2- combines with reactive iron in pore waters forming insoluble sulphides, mainly FeS, which accumulate in the sediment ultimately leading to the formation of FeS2. Anthropogenic heavy metal are generally adsorbed to or coprecipitated in these newly formed phases. However, if metals enter the system as coarse particles, as easily occurs in the Venice canals, a variety of bulk metal-sulphides can form as the result of direct sulphurisation of the original metallic compounds. The partitioning of sulphur compounds in sediments from 5 selected sites of the network was investigated by collecting 35 cm-long cores. Pore water concentration of heavy metals, SO42- and S2- as well as the distribution of solid-phase sulphur (S0, AVS, CRS) and AVS-metals concentrations were considered revealing interesting implications, particularly for As and S2-. The gravity-separation of dried sediment aliquots permitted a detailed investigation on sulphide particles by reflected light optical microscopy, and the study of their microchemistry by scanning electron microscopy combined to energy dispersive x-ray fluorescence. The results show as Cu and Zn sulphides are commonly found in replacement of original compounds and can coexist in intimate association with FeS and FeS2, sometimes forming reaction rims.