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The present dataset was collected to evaluate the environmental stressors on a lacustrine basin in the Eastern Alps of glacial origin that has been affected in recent years by natural and anthropogenic events such as the construction of a hydroelectric power plant and a series of strong earthquakes during 1976-1977. We collected sediment cores in different sites from the lake margins to the depocenter and performed a multiproxy analysis of sediment sample to highlight lake stratigraphy and major changes occurring at a decadal scale (Polonia et al., [1]). The integrated analyses of sedimentological, geochemical, isotopic, mineralogical and micropaleontological analyses aimed at reconstructing changes in sediment composition and define the triggering mechanisms of altered environmental conditions. The dataset demonstrates that evaluating ex post the effects of artificial modification in a natural environment during relatively long time spans (decades) can provide important insights for managing and protection strategies in similar environments worldwide (C) 2021 The Authors. Published by Elsevier Inc.

We examined the transport of sediments and their surficial pathways from the mouth of Neretva River, through the Neretva Channel, toward the Adriatic Sea. This research was based on twelve box-cores and five grab samples collected within the Neretva Channel. Sediment dynamics were evaluated using several proxies, such as organic matter, radiochemical isotopes and select metal concentrations and physical parameters. The data analysis showed that the influence of the river on particle distribution along the Neretva Channel decreases northward, with an estimated sediment accumulation rate ranging from 1.9 to 8.5 mm/yr. The lowest accumulation rate was found in the sector not influenced by river inflow, whereas the preferential sediment accumulation area is in the center of the basin. We speculate that dispersion and accumulation of sediments are both driven by an eddy in the waters of the Neretva Channel triggered/or intensified seasonally by the interaction of karstic springs, river input and Adriatic Sea waters. Our results indicate that the anthropogenic factor does not affect the concentration of metals within the channel and that the river particles dynamics determine the Pb areal distribution, while Cr and Ni have a possible source located to the northwest of the river-mouth.

This study focused on the geochemical and sedimentological characterization of recent sediments from two marine sites (S1 and E1) located in the North Adriatic Sea, between the Po River prodelta and the Rimini coast. Major and trace metal concentrations reflect the drainage area of the Po River and its tributaries, considered one of the most polluted areas in Europe. Sediment geochemistry of the two investigated sites denote distinct catchment areas. High values of Cr, Ni, Pb and Zn detected in sediments collected in the Po River prodelta (S1 site) suggest the Po River supply, while lower levels of these elements characterize sediments collected in front of the Rimini coast (E1 site), an indication of Northern Apennines provenance. Historical trends of Pb and Zn reconstructed from the sedimentary record around the E1 site document several changes that can be correlated with the industrialization subsequent to World War II, the implementation of the environmental policy in 1976 and the effects of the Comacchio dumping at the end of 1980. At the S1 site, the down core distributions of trace elements indicate a reduction of contaminants due to the introduction of the Italian Law 319/76 and the implementation of anti-pollution policies on automotive Pb (unleaded fuels) in the second half of the 1980s.

The Lake of Cavazzo is a natural, lacustrine basin in the Friuli-Venezia Giulia region (NE Italy), which occupies a fluvio-glacial suspended valley of the Tagliamento river, at the southern front of the Alpine chain. The lake formed after the melting of major glacial tongues at the end of the Last Glacial Maximum, and has been affected in recent years by natural and anthropogenic events, with economic, cultural and environmental consequences. According to local witnesses, the lake environment has changed dramatically after the 1950s, when the basin was connected to a hydroelectric power plant collecting waters from a wider catchment area, as it served as its final discharge basin. In this work, based on a densely-spaced grid of high-resolution seismic reflection profiles complemented by sediment cores, we analysed the uppermost lake stratigraphy, highlighting major changes occurring at a decadal scale. Our main purpose is to verify whether and how the lake sediments record the transition from pristine/natural to artificial conditions, as well as the effects of multiple natural impacts including the 1976–77 Friuli earthquake sequence. The results of our analysis suggest varying environmental conditions of the lake after the 1950s indicated by changing sediment mineralogy, increased deposition of allochthonous clastic sediments, and recurrent episodes of anoxic conditions at the lake's floor, likely triggered by hyperpycnal flows derived from the hydroelectric power plant discharges. We also observe that the effects of the 1976–77 seismic sequence are recorded in the lake as resedimented levels, likely due to shaking, in situ deformation, landslides, and turbidity currents. Our results stress the importance of lacustrine environments as efficient recorders of anthropogenic and natural events.

Cheko, a small lake located in Siberia close to the epicentre of the 1908 Tunguska explosion, might fill a crater left by the impact of a fragment of a Cosmic Body. Sediment cores from the lake's bottom were studied to support or reject this hypothesis. A 175-cm long core, collected near the center of the lake, consists of an upper similar to 1 m thick sequence of lacustrine deposits overlaying coarser chaotic material. 210Pb and 137Cs indicate that the transition from lower to upper sequence occurred close to the time of the Tunguska Event. Pollen analysis reveals that remains of aquatic plants are abundant in the top post-1908 sequence, but are absent in the lower pre-1908 portion of the core. These results, including organic C, N and delta 13C data, suggest that Lake Cheko formed at the time of the Tunguska Event.

To obtain a quantitative estimate of the sediment accumulating on the muddy belt extending along the western Adriatic continental shelf, a budget was calculated based on the mass accumulation rates measured from more than one hundred activity–depth profiles of Pb-210. Cs-137 depth-distributions were used, when possible, to support Pb-210 results. Pb-210 profiles show quasi-monotonic declines in the foreset region of the central Adriatic clinoform. In the prodelta of the rivers Po and Isonzo, Pb-210 profiles are characterized by intervals of low and uniform activity, which are thought to be produced by flood deposition. Since the north Adriatic is shallow and occasionally affected by storms from Bora wind, sediments are not in steady-state and their accumulation is the net result of recurring deposition, resuspension and winnowing events. In the western Adriatic, mass accumulation rates range between 0.04 and 6.6 g cm-2 (cm to the minus 2) yr-1 (yr to the minus 1). Peak values were recorded in the Po and Isonzo prodeltas and along a narrow belt between Pescara and the Gargano promontory. Furthermore, the latter depocentre is located immediately seaward of the offlap break (40–50 m water depth) and parallels that of the most recent sigmoid of the HST. The integration of mass accumulation rates throughout the mud wedge of the north and central Adriatic gave a value of about 42.0 Tg yr-1 (yr to the minus 1) of sediment accumulating along the Italian coast. The balance between sediment accumulation and riverine sediment supply (about 46.6 Tg yr-1 (yr to the minus 1)) suggests an export of 4.6 Tg yr-1 (yr to the minus 1) to the south Adriatic basin and/or the Mediterranean Sea. The along-shore sediment transport is very effective and, in particular, 16.2 Tg yr-1 (yr to the minus 1) of sedimentary material (about 35% of the riverine supply) is transferred from north to central Adriatic, through the Ancona section.

Polychlorinated biphenyls (PCBs), dibenzo-p-dioxins (PCDDs), dibezofurans (PCDFs) and hexaclorobenzene (HCB) were determined in three sediment cores of the Venice Lagoon: I1, from the San Giuliano Canal that is likely the main source of pollutants for the study area; E, representing the lagoon sediment of the zone of Campalto; and M3, typical of a salt marsh environment and mostly subject to atmospheric inputs. Maximum concentrations were found in core I1: 25-1858 ngl-TE kg-1 (kg to the minus 1)(PCDD/fs), 1.7-13 micrograms kg-1 (kg to the minus 1)(HCB), and 107 - 717 micrograms kg-1 (kg to the minus 1) (PCBs) are surficial and peak values, respectively. The lagoon sediment (E), is much less contaminated: 24-47 ngl-TE kg-1 (kg to the minus 1) for PCDD/Fs, 2.3-3.6 micrograms kg-1 (kg to the minus 1) for HCB, and 56-203 micrograms kg-1 (kg to the minus 1) for PCBs whereas M3 shows the lowest values: 1.6-6.0 ngl-TE kg-1 (kg to the minus 1)for PCDDs/Fs, 0.3-0.6 micrograms kg-1(kg to the minus 1)for HCB, and 7.1-39 micrograms kg-1 (kg to the minus 1) for PCBs. In any case, the recent trend is toward a decrease of pollutant concentration. The chronology of cores E and M3 is based on both Pb-210 and Cs-137 activity depth profiles. The maximum concnetrations of PCDD/Fs, HCB, and PCBs correspond to the years 1949, 1980, and 1968, respectively. The homologue profiles of PCDD/Fs confirm that I1 has been subject to an industrial source while the other sites also recorded significant contributions, changing over time, of octa-chlorinated dioxin from combustion. a comparison of the pollutatn invetories, all normalised to PB-210 invetories, suggests that the atmospheric contribution to the contamination of the area of Campalto is low: the upper limits range from 6% (PCDD/Fs) to 17% (HCB).

Analyses of Mn, Cd, Cr, Cu, Pb, and Zn were carried out in a short core from a salt marsh of the Nador Lagoon (north-eastern Morocco) and in surficial sediment samples collected in the Martil river, which borders the industrial town of Tetouan. Three soil samples and a reservoir sediment were also collected around the town to check the effects of atmospheric delivery of contaminants. 137 Cs and 210 Pb activity-depth profiles were used to establish a chronology for the core, obtaining an apparent accumulation rate of 0.41 cm/y. The concentrations of anthropogenic metals in this marsh sediment are low and probably represent natural backgrounds. A recent decrease can be an effect of changing grain size. The Martil River sediments are slightly contaminated by Cu and Pb, whereas the soil samples present anomalous values of Cd and Zn.

A mooring was deployed in the southern Adriatic basin (1030 m depth) between April 1994 and October 1995. The mooring was equipped with two time-series sediment traps placed at 500 and 35 m above the bottom, respectively. Mass fluxes at both depths are characterised by high variability (26-1577 mg/cm 2 .y), without a clear seasonal trend. Particulate 210 Pb activities vary within a relatively limited range of values (13-74 dpm/g) and do not show any evident relationship with water depth. Activities are higher in winter. The correlation between 210 Pb activity and organic matter in the upper water column suggests that 210 Pb scavenging may be controlled by carbon cycle. On the contrary, at the near-bottom trap 210 Pb activity seems to be driven by the amount of particles, their residence time in the water column and the contribution of lateral advection. The mass balances of both particulate matter and 210 Pb require a very significant lateral input between the lower trap and the sea bottom. This flux is mainly consisting of resuspended sediment and seems to be episodic.

The Po River (Northern Italy) discharge represents a considerable input of the land-derived material entering the Mediterranean Sea. Most of its particulate and dissolved constituents are supplied to the sea in response to short-lived climate events. Although these floods exert first-order control on the transport of organic and inorganic elements, both composition and magnitude of the river material are poorly constrained during high discharge periods. In order to fill this knowledge gap, in this study we carried out an event response sampling in the Po River in November 2011. Beginning in early November, intense rainfall occurred in the Po watershed that resulted in a flood of ∼6000 m3 s−1 (2.5 year return period). Water samples were collected from the river before and during the flood. Dissolved nitrate, nitrite, ammonia, and silicate were measured and the particulate material was analyzed for total suspended sediment, elemental composition, δ13C, δ15N, grain-size, and 137Cs activity. Our results showed a temporal decoupling between solid and water discharge implying that predicted sediment loads simply derived from sediment rating curves could potentially give rise to large errors, especially when calculations are used to understand the sediment export in response short-lived events. The suspended organic material during high flow was dominated by soil organic matter while high δ15N indicated the influence of an additional 15N-enriched source (e.g., manure, sewage, and algal biomass) during low discharge. Because the concentrations of nitrite and ammonia were positively correlated with the content of particulate material in suspension, we inferred that nitrite and ammonia concentrations were driven by either bacteria activity (ammonification–nitrification) or ionic exchange whose rates were proportional to concentration of the suspended material. In addition, due to the dilution with nitrate-poor rainfall, the concentration of nitrate decreased with increasing water discharge. High concentrations of nitrate were instead attributable to the influx of nitrate-rich water from groundwater that is chronically contaminated and constitutes most of the baseflow during low flow. Our results indicate that the event-dominated transport in the Po drainage basin is particularly important for the organic matter supply as flood events account for at least one-third of the particulate annual export (organic carbon and nitrogen). Finally, this study has demonstrated the utility of event-response sampling for understanding the importance of event-dominated transport in rivers.

In view of the recent action in Marine Strategy Framework Directive, reconstructing the history of anthropogenic metal inputs and calculating the budgets for the northwestern part of the Italian Adriatic basin can provide a benchmark for comparison with new evidences and enlighten recent environmental changes. Among the metals, the attention was focused on Pb and Zn, as they provide the most significant anthropogenic signals. In 1988, areal distributions clearly identified the Po, Adige and Brenta rivers as the main sources of contaminants. The study area was divided in three compartments. The area in front of the Po delta represented a sink for metals but the accumulation of Zn and Pb integrated over the entire study area suggests an effective export throughout southern boundary. Most concentration-depth/year profiles in cores showed an upward increase from the Italian Unification (1861), with a still significant anthropogenic supply at the time of sampling.

Assessing pollution levels and trends in heavily impacted environments is important but hardly achievable due to the difficulty of recovering suitable undisturbed sediment records. An integrated approach is here presented to solve this kind of problem. It was adopted in the Augusta Bay (Italy) for the study of Hg historical inputs and present trends. Archive information on dredging and mud disposal, together with bathymetry and high-resolution seismic profiles, were used to identify suitable sampling sites. Undisturbed sediment cores were collected in the port and bay. Sediments were analyzed for depth distributions of radiotracers ((210)Pb and (137)Cs), Hg, and main sediment parameters (magnetic susceptibility, grain size, dry bulk density, mineralogy, and organic carbon and nitrogen contents). Hexachlorobenzene (HCB) was also analyzed as an additional time tracer, since its production history in the area was well-known. Results show that peak Hg contamination (up to 575 mg·kg(-1)) was reached in the 1970s. Technological improvements and waste treatment in the following years determined a consistent decrease, but high concentrations still affect surficial sediments (0.25-92 mg·kg(-1)). Hg-HCB correlation suggests that this situation is likely the effect of resuspension and redistribution of deep sediments by dredging and naval traffic.

The Neretva is the largest river of the eastern part of the Adriatic basin. Its catchment area is very broad and includes territories belonging to Bosnia, Herzegovina and, at the lowest reaches, Croazia. The river crosses areas exploited for agricultural, industrial and urban activities. Because of this, can become particularly severe given the location in karst area where erosion has already reached the geological base. The Neretva is characterized by a large amount of sediment that flows to the Adriatic sea into a narrow semi-enclosed basin, named Neretva Channel, located along the southernmost part of the Croatian coast. In order to contributeto the elevation of the distribution and the preservation potential of sedimentary deposits, the present study aims to trace the distribution of the Neretva River particle input toward the Adriatic Sea, in particular those associated to metal aggregates, and to follow their spatial vs. time distribution, using a suite of biogeochemical proxies like total and organic carbon, radiochemical data of delta 13 and distribution of some metals 1 Introduction Coastal areas are the places where the peculiarities of land-sea transition systems emerge more clearly, in terms of chemical, physical and biological changes, and where most human pressure occurs. Particles, which accumulate in marine sediments, originate from a combination of river discharge, runoff of agricultural soils, roads and urban settlements plus atmospheric dry and wet deposition. In these areas, the sediment composition is mainly controlled by local geology, but can also reflect anthropogenic discharge from industrial and urban activities, thus enhancing concentrations of both organic matter and metals. [1]. Eastern Adriatic coast, from Croatia to Albania, is a typical transgressional environment formed during the Late Pleistocene

Climate has been acknowledged as one of the main driving factors behind human development and in turn human activity may cause strong changes on marine ecosystems. Coastal areas represent very useful marine sedimentary archives to investigate the potential effects of human impact on shelf marine ecosystems. The high-resolution investigation presented here of a southern Tyrrhenian marine record from the continental shelf of the Salerno Gulf provides an unprecedented opportunity to study the main natural and human impact that have occurred in this area during the last five centuries. Evidence of an important turnover between carnivorous and herbivorous opportunistic planktonic foraminfera species is recorded after the Maunder event. In addition, after 1940 AD, a strong increase in the distribution pattern of the Globigerina bulloides species combined with a sudden increase in the abundance pattern of the benthic foraminifer Bulimina aculeata, and evident enhancement of benthic and planktonic foraminifera (as number of specimens per gram of dry sediment) can be directly associated to the effects of the construction of the Sele River dam (1934 AD).

Due to its remarkable sediment pollution caused by past industrial activities, the Mediterranean coastal area facing the town of Cogoleto (near Genoa) has been declared of “national interest”. Seven sediment cores were analysed to provide information on history and trend of heavy metal inputs, with a particular focus on Cr. Grain-size compositions and 210Pb chronologies account for a strong influence of terrigenous inputs near the coast and the mouth of the Lerone Creek (draining the industrial settlement), with sand contents and accumulation rates varying from 40.3% and 0.7 cm year−1 near shore to 2.5% and 0.1 cm year−1 offshore. Heavy metal concentrations are high, notably Cr and Ni, and to a lesser extent, Ag, Hg, Pb, Cu and Zn. Cr, that shows past values up to 3,642 µg g−1, presents only minor recent decreases. In the area, it has both natural and anthropogenic sources and their relative contributions were distinguished on the basis of Cr/Ni ratios. These are 1–1.5 in soils and rocks of the Lerone Creek catchment area but reach very high values (up to 10) in marine sediments due to the anthropogenic contribution. The anthropogenic influence is higher near the creek mouth, gradually decreases offshore and is negligible at the most distal site (ca. 2.9 km from the coast).

From November 2008 through May 2009, the North Italy experienced the highest precipitation period recorded over the last century. As a result, a long series of flood events occurred in the Po river (North Italy). This series of events ended with a large flood in early May 2009. An event-response sampling was carried out in the Po prodelta in April–May 2009 to characterize this latter event and to investigate the strata preservation in the stratigraphy record as a result of this series of floods. The water sampling was carried out during two periods of the flood, including early in the event under conditions of moderate river flow (~5000 m3 s−1) and 24 h later during the peak discharge (~8000 m3 s−1). At each station, profiles of conductivity, transmittance, and fluorescence were acquired whereas surface and bottom waters were sampled to collect sediments in suspension. In addition, sediment cores were collected in the Po prodelta before and after the peak flood. Biogeochemical compositions and sedimentological characteristics of suspended and sediment samples were investigated using a multi-proxy approach that included bulk and biomarkers analyses. Furthermore, 7Be down-core profiles and radiographs were used to analyze the internal stratigraphy of sediment cores. During moderate discharge, the water column did not show evidence of plume penetration. In surface waters, suspended sediment concentrations were found to be similar to low river discharge periods whereas the main OC was autochthonous. After 24 h, during the peak flood, water column properties and biogeochemical parameters exhibited marked changes indicating significant penetration of the turbid plume. However, suspended sediment concentrations and terrigenous OC content in surface waters were still less then expected based on the discharge. These results suggested that, since material enters the Adriatic as buoyancy-driven flow with a reduced transport capacity, settling and flocculation processes result in trapping a significant fraction of land-derived material prior to reaching the subaqueous prodelta. In spite numerous floods occurred from November 2008 through April 2009, sediment cores collected in late April 2009 did not exhibited significant evidence of event-strata preservation. Since these floods were ordinary (2–3 y return period), the lack of preservation indicates that most of the sediment supply during these oridinary events does not reach the subaqueous prodelta. However, it is likely that modest sediment deposition occurs during these oridinary floods but thicknesses of these event-strata are not sufficient to compete with post-depositional processes. Stations in the north and central prodelta were re-occupied after the peak of the May 2009 flood. Based on 7Be and radiographs, we estimated that 17 and 6 cm event-layers, respectively. Selective trapping of coarse material occurred in the central prodelta likely because of the geomorphologic setting of the central outlet characterized by an estuary-like mouth. Despite these settling processes, lignin-based parameters indicated that sources of the terrigenous OC were fairly homogenous throughout the channel network and between size-fractions.

I lavori presentati dai ragazzi nell'ambito del progetto "Il linguaggio della ricerca" hanno superato spesso le nostre aspettative. Infatti, sebbene come "oggetto" divulgativo, la nostra prioritaria richiesta sia sempre stata quella della stesura di un articolo giornalistico, e di tale natura abbiamo raccolto negli anni prodotti di ottima qualità come contenuti ed impostazione, altri mezzi divulgativi utilizzati dagli studenti sono risultati di maggiore impatto. I ragazzi, seguendo l'indicazione di utilizzare un linguaggio accattivante, semplice e chiaro, rivolto a lettori non esperti, ma esatto nell'uso del bilinguismo, hanno risposto proponendo anche l'utilizzo di moderni metodi di comunicazione quali fumetti e filmati, poster, diapositive, animazioni, interi giornalini, libri o addirittura libroni e completi siti web. Spesso approfondendo un argomento di scienza hanno finalizzato le loro competenze per realizzazioni veramente originali. Tantissimi i lavori che ci hanno stupito per la loro creatività, ma anche per la loro accuratezza scientifica e organizzazione nella presentazione delle idee. Con i fumetti i ragazzi hanno raccontato la scienza, coniugando la scrittura con l'immagine per esemplificare teorie molto complesse. Argomenti come la relazione tra salute e nutrizione sono stati presentati ricorrendo a notissime strisce di Super-Eroi o a favole. L'importanza di una corretta alimentazione nella difesa della salute è stata raffigurata, per esempio, da studenti del Rambaldi-Valeriani di Imola utilizzando la favola dei tre porcellini: le specie radicaliche aggressive e dannose al corpo umano sono state rappresentate dalla figura del lupo, il fumo e un'alimentazione ricca di grassi e dolci si sono trasformate nelle casette dei due porcellini in pericolo, mentre frutta e verdura, che costituiscono la casetta del terzo porcellino, sono in grado di mettere al sicuro quest'ultimo da tutti i pericoli. I ragazzi dell'ITAS Garibaldi di Cesena hanno invece descritto un esperimento con vignette così calzanti da lasciare senza parole: concetti complessi, come l'irradiamento di campioni e l'analisi dei risultati sono raccontati con disegni che risultano di grande impatto esplicativo. Le ricerche esposte ai ragazzi hanno ispirato anche la creazione di cartoon. E così l'attacco dei radicali liberi alle cellule e ai loro componenti proteici è stato trasformato da studenti del Rambaldi-Valeriani in una divertentissima guerra spaziale, "Protein Wars" rifacendosi al celebre film Star Wars, in cui le specie dannose sono degli extraterrestri che vogliono invadere la Terra, cioè la cellula, che però viene difesa grazie alla "forza" di abilissimi combattenti "Jedi" (sostanze antiossidanti). La favola come genere letterario è stata utilizzata anche ne "La favola del principe OH", un video animato da studenti del Liceo Galvani di Bologna con vera maestria e accompagnato da una scelta adeguata di brani musicali. La storia è quella fantastica dell'amore fra gli ioni OH- ed H+, che danno luogo alla felice unione di una molecola d'acqua, scissa poi dalle "cattive" radiazioni che distruggono la serenità del regno della chimica. Nel finale a sorpresa la vitamina C arriva a portare via il radicale OH, che capisce che anche un grande amore può finire per una giusta causa: per impedire "l'ossidazione del regno".

Several natural and anthropogenic processes can lead to the formation of polycyclic aromatic hydrocarbons (PAHs), a well known class of compounds, many of which with mutagenic and carcinogenic properties (Nielsen et al., 1995), that are regarded as priority pollutants by the US Environmental Protection Agency (US EPA, 1993). Anthropogenic sources include combustion of fossil fuels, coal gasification and liquification processes, petroleum cracking, waste incineration and production of: coke, carbon black, coal tar pitch and asphalt, (McCready et al., 2000). Another common anthropogenic source of PAHs is spillage of fossil fuels, both unrefined and refined products. PAHs also stem from natural combustion sources such as forest fires, and certain compounds (perylene and retene) are thought to be diagenetically produced (Wakeham et al., 1980).

The Tam Giang-Cau Hai Lagoon, the largest in south east Asia, suffers from a great anthropogenic pressure and appears subject to a process of progressive environmental deterioration. To establish causes, history and trends of lagoon contamination, sediment samples representing three major parts of the systems were sampled and analysed for porosity, organic carbon, total nitrogen, d 13 C, grain size, radiotracers and PCBs. PCB surficial concentrations range from 10.2 to 24.5 l gk g � 1 , and maximum values are close to NOAA ERL guidelines. The downcore distribution of PCBs shows two well defined peaks in the core from Tam Giang (25.5 and 16.2 l gk g � 1 ), whereas the sediment from Cau Hai is characterised by a maximum at the surface. Therefore, present trends indicate that contamination is still increasing or slightly decreasing. The prevailing congeners are 3-CB and 4-CB, hence recent PCBs appear to be mostly originated by Aroclor 1016- and 1242-like mixtures, with some samples influenced also by Aroclor 1248. Present sources seem to be similar everywhere and probably they are widespread all over the territory of the Thua Thien-Hue province. � 2006 Elsevier Ltd. All rights reserved.

Five salt marsh sediment cores from different parts of the Venice Lagoon were studied to determine their depositional history and its relationship with the environmental changes occurred during the past approximately 100 years. X-radiographs of the cores show no disturbance related to particle mixing. Accretion rates were calculated using a constant flux model applied to excess (210)Pb distributions in the cores. The record of (137)Cs fluxes to the sites, determined from (137)Cs profiles and the (210)Pb chronologies, shows inputs from the global fallout of (137)Cs in the late 1950s to early 1960s and the Chernobyl accident in 1986. Average accretion rates in the cores are comparable to the long-term average rate of mean sea level rise in the Venice Lagoon ( approximately 0.25 cm y(-1)) except for a core collected in a marsh presumably affected by inputs from the Dese River. Short-term variations in accretion rate are correlated with the cumulative frequency of flooding, as determined by records of Acqua Alta, in four of the five cores, suggesting that variations in the phenomena causing flooding (such as wind patterns, storm frequency and NAO) are short-term driving forces for variations in marsh accretion rate.

Land-ocean coupling was investigated for the Adige River-Adriatic Shelf system by analyzing precipitation, water discharge and suspended load records over the period 1922-2000 and by comparing them with the Pb and porosity depth profiles of 4 marine cores taken along the riverborne sediment transport pathway on the shelf. The results show that precipitation was affected only by minor variations in yearly and seasonal amounts but was accompanied by a significant decrease (increase) in the number of wet days (precipitation intensity). River discharge - which is strongly influenced by total precipitation as well as by the number of wet days (in contrast to the quantitatively less important precipitation intensity) - shows a continuous decrease throughout the whole period. A significant decrease in suspended load is recorded after the 1940s, and meteorological and hydrological data suggest a major discontinuity over the same period, which was also recorded by marine sediments as a significant decrease in accumulation rates of fine materials. After the 1970s a further change in water discharge is observed in the river-system lowlands, recorded on the Adriatic shelf as intermittent sediment accumulation, and probably related to major floods. Changes seem to be mostly anthropogenic, such as progressive withdrawal of water and sediment for agricultural and civil uses, as well as damming for irrigation purposes and for generation of electricity. © Inter-Research 2006.

Biomass gasification for energy or hydrogen production is a field in continuous evolution, due to the fact that biomass is a renewable and CO2 neutral source. The ability to produce biomass-derived vehicle fuel on a large scale will help to reduce greenhouse gas and pollution, increase the security of European energy supplies, and enhance the use of renewable energy. The Va¨rnamo Biomass Gassification Centre in Sweden is a unique plant and an important site for the development of innovative technologies for biomass transformation. At the moment, the Va¨rnamo plant is the heart of the CHRISGAS European project, that aims to convert the produced gas for further upgrading to liquid fuels as dimethyl ether (DME), methanol or Fischer-Tropsch (F-T) derived diesel. The present work is an attempt to highlight the conditions for the reforming unit and the problems related to working with streams having high contents of sulphur and alkali metals.

Coastal sediments from the northern Adriatic Sea were analyzed for Cs-137 and Cs-134 from the Chernobyl accident to better understand the transport and sedimentation processes in a marine area strongly influenced by the delivery the of suspended matter from the Po River. In particular, the suitability of Cs-137 as a tool for studying sediment accumulation rates was evaluated. Radionuclide distributions are determined by the influence of the river and the grain size composition that is a funciton of the hydrodynamic processes. With respect to pre-Chernobyl values, Cs-137 surficial activities were increased from 3 to 13 times, and inventories up to 3 times. Four types of Cs-137 activity-depth profiles were found, being representative of different combinations of sediment accumulation and radiotracer displacement within the surficial layers. At some sites, sediment accumulation rates of 1.6-1.8 cm y to the minus 1 caused the formation of a sub-surficial peak. At the other locations, the Chernobyl peak of Cs-137 was was still confined at the water–sediment interface with some downward penetration due to mixing and diffusion. In general, molecular diffusion is the prevailing mechanism but the incidence of mixing is very significant at three sites (58–71%).

Three sediment cores were collected in the Venice Lagoon: two from mud flats (E, F) and one from the San Giuliano Canal (I1), which borders the industrial district. Samples were analysed for the 15 polycyclic aromatic hydrocarbons (PAHs) listed as priority pollutants by the U.S. EPA. Sediment chronologies were established using both 137Cs and 210Pb activity-depth profiles, and confirmed by independent information. The highest levels of PAHs, up to 16,474 µg kg-1, characterise the sediment from the industrial canal. In lagoon sediments maximums were 618–1,531 µg kg-1, while surficial values were 315 and 810 µg kg-1. Dated concentration-depth profiles suggest that highest inputs occurred in the first half of last century and were followed by significant decreases. The industrial activities played a major role in the PAH contamination of lagoon sediments, as suggested by the high concentration gradients in the study area. The main source, based on the information provided by the relative abundance of congeners, is represented by high temperature combustion processes. Petrogenic sources may have influenced some samples, whereas the effects of selective transport and diagenesis are difficult to assess. The sediment of the industrial canal has the potential to occasionally cause adverse effects in sensitive species.

Three sediment cores were collected in the Venice Lagoon: two from mud flats (E, F) and one from the San Giuliano Canal (Il), which borders the industrial district. Samples were analysed for the 15 polycyclic aromatic hydrocarbons (PAHs) listed as priority pollutants by the U.S. EPA. Sediment chronologies were established using both 137Cs and 210Pb activity-depth profiles, and confirmed by independent information. The highest levels of PAHs, up to 16,474 μg kg−1, characterise the sediment from the industrial canal. In lagoon sediments maximums were 618−1,531 μg kg−1, while surficial values were 315 and 810 μg kg−1. Dated concentration-depth profiles suggest that highest inputs occurred in the first half of last century and were followed by significant decreases. The industrial activities played a major role in the PAH contamination of lagoon sediments, as suggested by the high concentration gradients in the study area. The main source, based on the information provided by the relative abundance of congeners, is represented by high temperature combustion processes. Petrogenic sources may have influenced some samples, whereas the effects of selective transport and diagenesis are difficult to assess. The sediment of the industrial canal has the potential to occasionally cause adverse effects in sensitive species.

This paper reports the results of determinations of137Cs and other radionuclides in bottom sediments and suspended matter collectedin a coastal zone of the northern Adriatic off the lagoon of Venice and at the estuary of the Adige River. The activity, behaviour and distribution of137Cs and some natural radionuclides were determined in materials sampled up to 1984. Various artificial radionuclides (134Cs,103Ru,106Ru, together with137Cs introduced by the accident Chernobyl) were detected samples collected in 1986. The study of the distribution of137Cs as a function of sediment properties showed that this radionuclide preferentially accumulates in the finest particles (6–12 phi, i.e. 16-0.24 μm range) and is taken up by adsorpion surface processes. This radioisotope has been used as tracer for recent sedimentary processes occurring in the study area and also as a tracer for predicting the fate of other inorganic and organic pollutants reaching the sediments by natural process. Exceptionally high values of radioactivity were observed after the Chernobyl accident in the estuary of the Adige River, particularly in suspended matter.

Riflessioni sulla produzione pittorica e fotografica dell'artista inglese David Hockney alla luce del suo costante interesse per il mondo della letteratura.

Premessa generale ai volumi prodotti nell'ambito del PRIN 2005 su Letteratura e cultura visuale

Introduzione metodologica al volume in oggetto

Il saggio fa riferimento ai dibattiti critici e teorici sulle fotografie di tortura dal carcere di Abu Ghraib per uno studio sulla postmemory e l'etica della memoria. Si incentra sulla rappresentazione, trasmissione ed elaborazione della memoria nei media, nella letteratura - nelle sue diverse espressioni - e nelle analisi critiche. Le fotografie da Abu Ghraib vengono analizzate nella loro ricezione e 'trasformazione', nonché nelle loro 'radici' politico-culturali. Gli studi della tecnologia come mediazione e produzione di realtà, così come lo studio della rappresentazione come formazione discorsiva, inducono a riconoscere nella ricezione di queste fotografie di tortura e nella loro interpretazione una politica di manipolazione e occultamento della memoria (che sia volontaria o involontaria è ancora più perturbante). E tuttavia è proprio nella ricezione e nelle metodologie di analisi critiche che questa questione diviene cruciale. Da un lato esse sono una condanna della guerra basata sull’eterna mitologia della lotta tra due opposte civiltà, dei modi in cui la guerra e il terrore contro il terrorismo è descritto, giudicato, e disseminato. Nella circolazione globalizzata, le fotografie che rappresentano la tortura e il rapporto tra prigionieri e soldati hanno una funzione ambivalente. Da un alto rivelano, e condannano, dall’altro possono indurre una visione della guerra da turista globale. E’ nostra responsabilità decostruire questa ambivalenza. Così come è stato fatto rilevare a proposito dell’Olocausto, la ripetizione delle stesse immagini ha in maniera disturbante portato con sé la radicale decontestualizzazione dal loro contesto originale di produzione (e ricezione). Se queste immagini, nella loro ripetizione ossessiva, limitano o delimitano il nostro archivio personale e collettivo sul trauma, possono esse indurre un discorso etico nel periodo successivo? Agiscono come cliché, significanti vuoti che ci proteggono e distanziano dal problema, pur nell’orrore? Oppure, al contrario, la ripetizione in se stessa ri-traumatizza rendendo sia gli osservatori distanti che gli eredi della memoria vittime (o carnefici) surrogati? Per non incorrere nell’errore critico che alcuni studiosi denunciano, le fotografie di Abu Ghraib non solo pongono i problemi a cui prima accennavamo, ma anche quelli legati all’abitudine dello sguardo, alla costruzione dell’orrore come performance. Una volta riconosciuta l’indubbia funzione e l’indubbio valore di denuncia che è derivato dall’aver rese pubbliche queste fotografie, il problema non si pone solo in termini di censura o liberalizzazione, ma anche in termini di politica della ricezione. Per esempio occorre pensare anche alla responsabilità etica di acquisire e mantenere uno sguardo ‘disabituato’ e ostinatamente non voyeristico nei confronti dall’assemblaggio mediatico dell’orrore. Ma, ad esempio, si tratta anche di non dimenticare di avere visto o di rifiutare non già di guardare, ma di vedere.

Si analizza la saggistica prodotta dai maggiori romanzieri postcoloniali, da Rushdie (di cui si esaminano i saggi contenuti in "Imaginary Homelands" e "Step Across This Line") a Margaret Atwood ("Negotiating with the Dead"), da J. M. Coetzee ("Stranger Shores") a Ben Okri ("A Way of Being Free"), alla luce della speculazione di Edward Said, e del suo "testamento spirituale", il saggio postumo "Humanism and Democratic Criticism". Si tratta del primo saggio apparso nella nostra lingua sulla saggistica postcoloniale e, in particolare, sulla produzione non fiction di alcuni tra i maggiori scrittori postcoloniali di lingua inglese.

Nelle sue innumerevoli metamorfosi giapponesi, Wuthering Heights rappresenta uno degli esempi meglio riusciti di transmedialità a livello globale. Nella feconda contaminazione di generi e stili iniziata all’inizio degli anni Venti in Giappone - grazie alla mediazione accademica di Edmund Blunden, nonché alla prima traduzione di Yamato Yasuo del 1932 – il testo originale di Emily Brontë prende strade inaspettate. Insospettabili. Da romanzo, si trasforma in musical per il teatro di rivista Takarazuka fino ad approdare sul grande schermo in una versione irriconoscibile e dislocata nel tempo ad opera del cineasta Yoshida Yoshishige. Numerose saranno le versioni manga nella seconda metà del Novecento, anche in ambito omoerotico. Riletture che spingono a riflettere sul rapporto che si instaura tra centro e periferia. Tra i confini del romanzo e i metatesti infiniti che da questo possono e potranno scaturire.

By showing how the all main topics and themes of cultural studies can be found in Salman Rushdie's novel Midnight's Children, this essay stresses the relevance of Rushdie’s novel as a one of the most accomplished instances of a modern classic, and a perfect example of a postcolonial “passage” into the contemporary World literature.

The essay analyses two texts, Black Safari, a 1972 ‘mockumentary’ directed by Colin Luke, and Behind the Frontlines (1988), a travelogue by Ferdinand Dennis. Both texts operate a re-definition of Britishness, defined by Stuart Hall in his essay “Whose Heritage” as a process which implies not a simple inclusion in but a complete re-vision of the national tradition. Black Safari is a parody of the exploration documentary which presents the reversal of a colonial scientific survey: “Time has changed. It is time we have our Livingstones, our Mungo Parks, our Stanleys”. It tells the journey of a group of Africans approaching the “dark” coasts of Britain and sailing up the Liverpool to Leeds canal in order to locate the geographical centre of this “remote” island. The group is composed by a naturalist, an anthropologist, a reporter, and a navigator who find and discover a mysterious and hostile environment, collect specimens, rename places and plants, meet the local tribesmen and try to understand their customs and their “unintelligible dialect”. Behind the Frontline collects Ferdinand Dennis’ impressions after a journey undertaken in the late Eighties across the ‘Midlands’, from Liverpool to London-Brixton, via Sheffield, Birmingham, Cardiff, Bristol and Bath. He narrates his encounters with different black communities, searching for their physical and cultural space within a Britain in decline, still “struggling to come to terms with its loss of Empire and diminished world stature”.

The reforming of hot gas generated from biomass gasification and high temperature gas filtration was studied in order to reach the goal of the CHRISGAS project: a 60% of synthesis gas (as x(H2)+ x(CO) on a N2 and dry basis) in the exit gas, which can be converted either into H2 or fuels. A Ni-MgAl2O4 commercial-like catalyst was tested downstream the gasification of clean wood made of saw dust, waste wood and miscanthus as herbaceous biomass. The effect of the temperature and contact time on the hydrocarbon conversion as well as the characterization of the used catalysts was studied. Low (