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Stefano Covelli is an associate professor of geochemistry at the University of Trieste.
At the Nalón River estuary (Asturias, Northern Spain), the occurrence of Hg is due to historical mining activity which has resulted in environmental issues of great concern. Although several studies have investigated the sediment compartment regarding Hg contamination, no information is currently available on the fate of Hg and MeHg in the water column. Considering different hydrodynamic/seasonal conditions, water samples were collected along the estuary to evaluate Hg and MeHg distribution and partitioning behaviour between solid and aqueous phases. The complementary effect of the river discharge and tidal currents contributed to the prevalence of the dissolved (4.02 ± 1.33 ng L−1) or particulate (8.37 ± 4.20 ng L−1) Hg under different conditions of discharge in summer and autumn, respectively. Conversely, particulate MeHg prevailed when the river flow was low, especially at the estuary mouth (25.8 ± 19.1 pg L−1) and most likely due to the resuspension of fine particles promoted by a stronger tidal current. In comparison with the total Hg concentration, extremely low amounts of dissolved and particulate MeHg were observed, and strong interactions between MeHg and organic carbon highlighted a negligible risk of increased mobility and potential bioaccumulation of MeHg.
Elena Pavoni; Efren García-Ordiales; Stefano Covelli; Pablo Cienfuegos; Nieves Roqueñí. Legacy of Past Mining Activity Affecting the Present Distribution of Dissolved and Particulate Mercury and Methylmercury in an Estuarine Environment (Nalón River, Northern Spain). Applied Sciences 2021, 11, 4396 .
AMA StyleElena Pavoni, Efren García-Ordiales, Stefano Covelli, Pablo Cienfuegos, Nieves Roqueñí. Legacy of Past Mining Activity Affecting the Present Distribution of Dissolved and Particulate Mercury and Methylmercury in an Estuarine Environment (Nalón River, Northern Spain). Applied Sciences. 2021; 11 (10):4396.
Chicago/Turabian StyleElena Pavoni; Efren García-Ordiales; Stefano Covelli; Pablo Cienfuegos; Nieves Roqueñí. 2021. "Legacy of Past Mining Activity Affecting the Present Distribution of Dissolved and Particulate Mercury and Methylmercury in an Estuarine Environment (Nalón River, Northern Spain)." Applied Sciences 11, no. 10: 4396.
Among potential toxic elements (PTEs), arsenic (As) and mercury (Hg) are well known for the toxicity of their different chemical species and diffusion in the environment via several anthropic sources (i.e., industrial settlements, mining activity). Bottom sediments often become a repository for As and Hg, although they may be considered a potential secondary source of these elements into the water column depending on their speciation and mobility. Focusing on the most recent studies (since 2019) on the occurrence of As and Hg in contaminated aquatic sediments, the aim of this review is to give an overview of the current understandings on the complex biogeochemical cycle of these elements in this environmental media. The main biogeochemical factors governing the transformations of As and Hg among their different chemical species were synthesised, highlighting those driving the formation of more mobile and/or bioavailable forms. Additionally, the most advanced analytical techniques for the determination of the different chemical species of As and Hg in sediments are briefly presented.
Alessandro Acquavita; Federico Floreani; Stefano Covelli. Occurrence and speciation of arsenic and mercury in alluvial and coastal sediments. Current Opinion in Environmental Science & Health 2021, 22, 100272 .
AMA StyleAlessandro Acquavita, Federico Floreani, Stefano Covelli. Occurrence and speciation of arsenic and mercury in alluvial and coastal sediments. Current Opinion in Environmental Science & Health. 2021; 22 ():100272.
Chicago/Turabian StyleAlessandro Acquavita; Federico Floreani; Stefano Covelli. 2021. "Occurrence and speciation of arsenic and mercury in alluvial and coastal sediments." Current Opinion in Environmental Science & Health 22, no. : 100272.
The cycling of metal(loid)s at the sediment–water interface (SWI) was evaluated at two selected sites (VN1 and VN3) in an active fish farm in the Grado Lagoon (Northern Adriatic, Italy). In situ experiments using a transparent benthic chamber and the collection of short sediment cores were performed, to investigate the behavior of metal(loid)s in the solid (sediments) and dissolved (porewaters) phases. Total and labile concentration of metal(loid)s were also determined in sediments, to quantify their potential mobility. Comparable total concentrations were found at both sites, excluding As, Mn, Pb and V, which were higher at VN3. Metal(loid) porewater profiles showed a diagenetic sequence and a close dependence with redox (suboxic/anoxic) conditions in the surface sediments. Positive diffusive fluxes along with benthic fluxes, particularly at the more oxic site, VN1, were found for almost all metal(loid)s, indicating their tendency to migrate towards the overlying water column. Despite sediments at two sites exhibiting high total metal(loid) concentrations and moderate effluxes at the SWI, the results suggest that they are hardly remobilized from the sediments. Recycling of metal(loid)s from the SWI would not constitute a threat for the aquatic trophic chain in the fish farm.
Elisa Petranich; Matteo Crosera; Elena Pavoni; Jadran Faganeli; Stefano Covelli. Behaviour of Metal(loid)s at the Sediment-Water Interface in an Aquaculture Lagoon Environment (Grado Lagoon, Northern Adriatic Sea, Italy). Applied Sciences 2021, 11, 2350 .
AMA StyleElisa Petranich, Matteo Crosera, Elena Pavoni, Jadran Faganeli, Stefano Covelli. Behaviour of Metal(loid)s at the Sediment-Water Interface in an Aquaculture Lagoon Environment (Grado Lagoon, Northern Adriatic Sea, Italy). Applied Sciences. 2021; 11 (5):2350.
Chicago/Turabian StyleElisa Petranich; Matteo Crosera; Elena Pavoni; Jadran Faganeli; Stefano Covelli. 2021. "Behaviour of Metal(loid)s at the Sediment-Water Interface in an Aquaculture Lagoon Environment (Grado Lagoon, Northern Adriatic Sea, Italy)." Applied Sciences 11, no. 5: 2350.
The sediments in the Gulf of Trieste (northern Adriatic Sea, Italy) are contaminated by mercury (Hg) due to historic mining which took place in Idrija (Slovenia). Despite many studies having been done regarding Hg, no information is available on the potential impact of dredging required along the main channel approaching the Port of Monfalcone. Sixteen surface sediment samples were collected along the channel to determine both total Hg concentration and chemical species using the thermo-desorption (TD) technique. Six samples were also chosen to apply a selective sequential extraction (SSE). The TD technique showed the maximum Hg release approximately at 260 and 335°C, corresponding to metacinnabar (β-HgS) and cinnabar (α-HgS), respectively. The SSE demonstrated that Hg was mainly associated with poorly soluble or insoluble compounds (98.7%). A resuspension event over a limited period of time can be considered of negligible impact to the water column due to the scarce Hg mobility from sediments.
Stefano Covelli; Elisa Petranich; Elena Pavoni; Sergio Signore. Can Sediments Contaminated by Mining be a Source of Mercury in the Coastal Environment Due to Dredging? Evidence from Thermo-Desorption and Chemical Speciation. Bulletin of Environmental Contamination and Toxicology 2021, 106, 942 -948.
AMA StyleStefano Covelli, Elisa Petranich, Elena Pavoni, Sergio Signore. Can Sediments Contaminated by Mining be a Source of Mercury in the Coastal Environment Due to Dredging? Evidence from Thermo-Desorption and Chemical Speciation. Bulletin of Environmental Contamination and Toxicology. 2021; 106 (6):942-948.
Chicago/Turabian StyleStefano Covelli; Elisa Petranich; Elena Pavoni; Sergio Signore. 2021. "Can Sediments Contaminated by Mining be a Source of Mercury in the Coastal Environment Due to Dredging? Evidence from Thermo-Desorption and Chemical Speciation." Bulletin of Environmental Contamination and Toxicology 106, no. 6: 942-948.
When mines are decommissioned, tailings piles can act as sources of contamination for decades or even centuries. Tailings, which usually contain high concentrations of metals and trace elements, can be reprocessed for a secondary recovery of valuable elements with an innovative approach to a circular economy. This study offers new results for tailings ponds characterisation and chemical content prediction based on an integrated geophysical-geochemical approach. The study of the Raibl Pb-Zn tailings impoundment was done using bulk chemical analysis on borehole samples, Electrical Resistivity Tomography surveys, and Ground Penetrating Radar measurements. We found valuable and statistically significant correlations between the electrical resistivity of the mining impoundments and the metal distribution, thus providing a practical opportunity to characterise large volumes of metal-bearing tailings. In particular, these results can be useful to aid in the development of environmental monitoring programs for remediation purposes or to implement economic secondary recovery plans.
Nicolò Barago; Stefano Covelli; Mara Mauri; Sara Oberti di Valnera; Emanuele Forte. Prediction of Trace Metal Distribution in a Tailings Impoundment Using an Integrated Geophysical and Geochemical Approach (Raibl Mine, Pb-Zn Alpine District, Northern Italy). International Journal of Environmental Research and Public Health 2021, 18, 1157 .
AMA StyleNicolò Barago, Stefano Covelli, Mara Mauri, Sara Oberti di Valnera, Emanuele Forte. Prediction of Trace Metal Distribution in a Tailings Impoundment Using an Integrated Geophysical and Geochemical Approach (Raibl Mine, Pb-Zn Alpine District, Northern Italy). International Journal of Environmental Research and Public Health. 2021; 18 (3):1157.
Chicago/Turabian StyleNicolò Barago; Stefano Covelli; Mara Mauri; Sara Oberti di Valnera; Emanuele Forte. 2021. "Prediction of Trace Metal Distribution in a Tailings Impoundment Using an Integrated Geophysical and Geochemical Approach (Raibl Mine, Pb-Zn Alpine District, Northern Italy)." International Journal of Environmental Research and Public Health 18, no. 3: 1157.
The Marano and Grado Lagoon (Northern Adriatic Sea) has been affected by mercury (Hg) contamination coming from two sources, mining activity and discharges from a chlor-alkali plant (CAP). Sediments and water contamination have been previously well characterised, but little is known about the atmospheric compartment, where Hg is easily emitted and can persist for a long time as gaseous elemental mercury (GEM). In this work, atmospheric GEM levels and its spatial distribution over the lagoon were monitored at several sites by means of both continuous discrete instrumental measurements over several months and the determination of Hg bioaccumulated in lichens (Xanthoria parietina L.). Average GEM levels varied from 1.80 ± 0.74 to 3.04 ± 0.66 ng m−3, whereas Hg in lichens ranged between 0.06 to 0.40 mg kg−1. In both cases, the highest values were found downwind of the CAP, but excluding this point, spatial patterns of Hg in the atmosphere and lichens reflected the concentration of this metal in the sediments of the lagoon, showing a decrease moving westward. These results could indicate that the lagoon acts as a secondary source of Hg into the atmosphere: future work is needed to characterise the quantity of releases and depositions at different environments inside the lagoon.
Federico Floreani; Nicolò Barago; Alessandro Acquavita; Stefano Covelli; Nicola Skert; Pablo Higueras. Spatial Distribution and Biomonitoring of Atmospheric Mercury Concentrations over a Contaminated Coastal Lagoon (Northern Adriatic, Italy). Atmosphere 2020, 11, 1280 .
AMA StyleFederico Floreani, Nicolò Barago, Alessandro Acquavita, Stefano Covelli, Nicola Skert, Pablo Higueras. Spatial Distribution and Biomonitoring of Atmospheric Mercury Concentrations over a Contaminated Coastal Lagoon (Northern Adriatic, Italy). Atmosphere. 2020; 11 (12):1280.
Chicago/Turabian StyleFederico Floreani; Nicolò Barago; Alessandro Acquavita; Stefano Covelli; Nicola Skert; Pablo Higueras. 2020. "Spatial Distribution and Biomonitoring of Atmospheric Mercury Concentrations over a Contaminated Coastal Lagoon (Northern Adriatic, Italy)." Atmosphere 11, no. 12: 1280.
Mercury (Hg) is a global pollutant, being highly persistent in the atmosphere, in particular gaseous elemental mercury (GEM), which can easily be emitted and then transported over long distances. In the Gulf of Trieste (northern Adriatic Sea, Italy), contamination by Hg is well characterised but little is known regarding the concentrations, sources and fate of GEM in the atmosphere. In this work, discrete measurements of GEM were recorded from several sites at different times of the year. The database is consistent with temporal night-day variations monitored using a continuous real-time device. The meteorological conditions were collected as ancillary parameters. GEM levels varied from –3) to 48.5 ng m–3 (mean 2.7 ng m–3), with no significant differences found among sites. A clear daily pattern emerged, with maximum values reached just after sunset. Air temperature, relative humidity, wind speed and direction were identified as the main micrometeorological factors influencing both the spatial and temporal variation of GEM. Our results show that average atmospheric GEM values are higher than the natural background of the Northern Hemisphere and will be useful in future selection regarding the most suitable sites to monitor atmospheric Hg depositions and fluxes from soil and water.
Nicolò Barago; Federico Floreani; Alessandro Acquavita; José Esbrí; Stefano Covelli; Pablo Higueras. Spatial and Temporal Trends of Gaseous Elemental Mercury over a Highly Impacted Coastal Environment (Northern Adriatic, Italy). Atmosphere 2020, 11, 935 .
AMA StyleNicolò Barago, Federico Floreani, Alessandro Acquavita, José Esbrí, Stefano Covelli, Pablo Higueras. Spatial and Temporal Trends of Gaseous Elemental Mercury over a Highly Impacted Coastal Environment (Northern Adriatic, Italy). Atmosphere. 2020; 11 (9):935.
Chicago/Turabian StyleNicolò Barago; Federico Floreani; Alessandro Acquavita; José Esbrí; Stefano Covelli; Pablo Higueras. 2020. "Spatial and Temporal Trends of Gaseous Elemental Mercury over a Highly Impacted Coastal Environment (Northern Adriatic, Italy)." Atmosphere 11, no. 9: 935.
Estuarine sediments must be dredged to allow for navigation, and where these sediments are placed after dredging depends upon guidelines based only on the total concentration of contaminants. However, resuspension events could seriously affect the mobility and speciation of contaminants, including potentially toxic trace elements stored in sediments. The effects of resuspension on the cycling of mercury (Hg) and arsenic (As) between the sediment and water column was investigated in a mesocosm study. Four experiments were conducted in three estuaries in northern Spain based on samples collected from sites which have been impacted by decommissioned Hg and As mines and periodically subjected to dredging activities. Designed to mimic the resuspension of particles, each of the experiments revealed that the release of Hg and As species does not only depend on the total concentration in the sediments (16.3–50.9 mg kg−1, for As and 0.52–5.01 mg kg−1 for Hg). The contribution from porewaters and the subsequent reductive dissolution and/or desorption appear to be the main processes responsible for the abrupt increase in dissolved Hg and As species (maximum release of 427% and 125%, respectively). In some cases, As and Hg continued to remain at high concentrations in the water column even after the experiments were completed, thus testifying to their critical persistence in the dissolved form. Conversely, at the other sites, the restoration of pre-resuspension conditions was observed only a few hours after resuspension, mainly due to the role of Fe oxy-hydroxides which provides suitable surfaces for adsorption and/or co-precipitation involving dissolved Hg (maximum removal of −58%) and As (maximum removal of −25%) species. The results of this research could be helpful to take appropriate decisions regarding dredging especially at the Nalòn estuary, where the release of dissolved As(V) and MeHg appeared to be favoured by sediment resuspension.
Efren García-Ordiales; Stefano Covelli; Greta Braidotti; Elisa Petranich; Elena Pavoni; Alessandro Acquavita; Lorena Sanz-Prada; Nieves Roqueñí; Jorge Loredo. Mercury and arsenic mobility in resuspended contaminated estuarine sediments (Asturias, Spain): A laboratory-based study. Science of The Total Environment 2020, 744, 140870 .
AMA StyleEfren García-Ordiales, Stefano Covelli, Greta Braidotti, Elisa Petranich, Elena Pavoni, Alessandro Acquavita, Lorena Sanz-Prada, Nieves Roqueñí, Jorge Loredo. Mercury and arsenic mobility in resuspended contaminated estuarine sediments (Asturias, Spain): A laboratory-based study. Science of The Total Environment. 2020; 744 ():140870.
Chicago/Turabian StyleEfren García-Ordiales; Stefano Covelli; Greta Braidotti; Elisa Petranich; Elena Pavoni; Alessandro Acquavita; Lorena Sanz-Prada; Nieves Roqueñí; Jorge Loredo. 2020. "Mercury and arsenic mobility in resuspended contaminated estuarine sediments (Asturias, Spain): A laboratory-based study." Science of The Total Environment 744, no. : 140870.
The Marano and Grado Lagoon (northern Adriatic Sea, Italy) is contaminated mainly by mercury (Hg) of mining and industrial origin. This work aims to investigate the sedimentary records of Hg of a tidal flat–saltmarsh (TF–S) system and to understand the role played by tidal fluxes in terms of the transport, accumulation and release of Hg due to the periodic flow of the tide. The complex history of the sources of Hg in the area of the TF–S system has resulted in several fluctuations of Hg in sediments over time; due to its higher sedimentation rate (1.3 cm year−1) than the subtidal areas of the Grado lagoon, the outer area of the TF–S system is more active in terms of accumulation (from 56 to 81 mg m−2 year−1) than the inner area. Fluxes were estimated at the mouth of a principal tidal creek by combining discrete hourly tidal flow measurements with weighed measurements of dissolved (DHg) and particulate (PHg) mercury obtained via water sample collection. Mercury, mainly in particulate form, is drained by the tidal creek from the marsh during a tidal semi-cycle. The highest flux of PHg was recorded during ebb tide in July (1071 mg). The calculation of the quantitative flows of PHg and DHg highlighted a tendency for Hg to be exported from the TF–S to the lagoon channel during a tidal semi-cycle. However, the results obtained here for the Hg fluxes do not allow for the depiction of a constant positive or negative budget as that found in the literature for macro-scale budget calculations at lagoon tidal inlets. A possible explanation for there being no constant trend in the PHg and DHg budget is that our TF–S system is located in a lagoon area where previous findings reported accretion or a balance situation between erosion and sedimentation processes.
Elisa Petranich; Luca Terribili; Alessandro Acquavita; Elena Pavoni; Leonardo Langone; Stefano Covelli. The Role of a Tidal Flat–Saltmarsh System as a Source–Sink of Mercury in a Contaminated Coastal Lagoon Environment (Northern Adriatic Sea). Aquatic Geochemistry 2020, 26, 245 -267.
AMA StyleElisa Petranich, Luca Terribili, Alessandro Acquavita, Elena Pavoni, Leonardo Langone, Stefano Covelli. The Role of a Tidal Flat–Saltmarsh System as a Source–Sink of Mercury in a Contaminated Coastal Lagoon Environment (Northern Adriatic Sea). Aquatic Geochemistry. 2020; 26 (3):245-267.
Chicago/Turabian StyleElisa Petranich; Luca Terribili; Alessandro Acquavita; Elena Pavoni; Leonardo Langone; Stefano Covelli. 2020. "The Role of a Tidal Flat–Saltmarsh System as a Source–Sink of Mercury in a Contaminated Coastal Lagoon Environment (Northern Adriatic Sea)." Aquatic Geochemistry 26, no. 3: 245-267.
A crucial step towards developing a more complete understanding of mercury (Hg) biogeochemical cycling in coastal environments is the measurement of the fluxes of gaseous elemental mercury (GEM), at the water-air interface (W-A interface). A floating flux chamber coupled with a real-time atomic adsorption spectrometer (Lumex-RA 915M) was applied to measure GEM concentrations, and to estimate the diurnal evasion flux at the water-air interface during three seasonal campaigns at four selected sites: two in a lagoon-based fish farm, one in an open lagoon environment highly impacted by long-term activities from the Idrija mercury mine (Slovenia), and an uncontaminated area of the Gulf of Trieste, the Bay of Piran (Slovenia). In this study, the regional background concentration measured at the uncontaminated site of atmospheric GEM (from 1.60 ± 0.95 to 2.87 ± 1.52 ng m−3) was determined. GEM fluxes at the W-A interface were found to be significantly higher during the summer (from 51.2 ± 8.8 ng m−2 h−1 to 79.9 ± 11.4 ng m−2 h−1) and correlated to incident solar radiation and water temperature. This finding confirms the importance of these two parameters in the photoreduction and biotic reduction of Hg2+ to dissolved gaseous mercury (DGM), which is volatile and easily released to the atmosphere in the form of GEM. These new insights will be of help for future estimates of Hg mass balance in one of the most contaminated areas in the Adriatic Sea.
Federico Floreani; Alessandro Acquavita; Elisa Petranich; Stefano Covelli. Diurnal fluxes of gaseous elemental mercury from the water-air interface in coastal environments of the northern Adriatic Sea. Science of The Total Environment 2019, 668, 925 -935.
AMA StyleFederico Floreani, Alessandro Acquavita, Elisa Petranich, Stefano Covelli. Diurnal fluxes of gaseous elemental mercury from the water-air interface in coastal environments of the northern Adriatic Sea. Science of The Total Environment. 2019; 668 ():925-935.
Chicago/Turabian StyleFederico Floreani; Alessandro Acquavita; Elisa Petranich; Stefano Covelli. 2019. "Diurnal fluxes of gaseous elemental mercury from the water-air interface in coastal environments of the northern Adriatic Sea." Science of The Total Environment 668, no. : 925-935.
One of the main environmental issues affecting coastal marine environments is the accumulation of contaminants in sediments and their potential mobility. In situ benthic chamber experiments were conducted at two tourist ports (marinas) located in the Gulf of Trieste, one in Slovenia and one in Italy. The aim was to understand if and where recycling at the sediment-water interface (SWI) may affect metal(loid)s. Short sediment cores were also collected near the chamber to investigate the solid (sediments) and dissolved phases (porewaters). Both diffusive and benthic fluxes were estimated to elucidate the release of metal(loid)s at the SWI. Total element concentrations and their labile fractions were determined in sediments to quantify their potential mobility. The total element contents were found to be two orders of magnitude higher in the Italian marina than in the Slovenian one, especially for Hg (up to 1000 mg kg−1), whereas the labile fraction was scarce or null. The opposite occurred in the Slovenian marina. Metal(loid)s in porewaters showed a clear diagenetic sequence and a close dependence upon the suboxic/anoxic conditions of sediments. The results suggest that although the sediments of the Italian marina exhibit the highest total metal(loid) concentration, these elements are scarcely remobilisable. Conversely, in the Slovenian marina, sediments seem to be comparatively more prone to release metal(loid)s at the SWI.
Elisa Petranich; Sara Croce; Matteo Crosera; Elena Pavoni; Jadran Faganeli; Gianpiero Adami; Stefano Covelli. Mobility of metal(loid)s at the sediment-water interface in two tourist port areas of the Gulf of Trieste (northern Adriatic Sea). Environmental Science and Pollution Research 2018, 25, 26887 -26902.
AMA StyleElisa Petranich, Sara Croce, Matteo Crosera, Elena Pavoni, Jadran Faganeli, Gianpiero Adami, Stefano Covelli. Mobility of metal(loid)s at the sediment-water interface in two tourist port areas of the Gulf of Trieste (northern Adriatic Sea). Environmental Science and Pollution Research. 2018; 25 (27):26887-26902.
Chicago/Turabian StyleElisa Petranich; Sara Croce; Matteo Crosera; Elena Pavoni; Jadran Faganeli; Gianpiero Adami; Stefano Covelli. 2018. "Mobility of metal(loid)s at the sediment-water interface in two tourist port areas of the Gulf of Trieste (northern Adriatic Sea)." Environmental Science and Pollution Research 25, no. 27: 26887-26902.
The Isonzo River has been demonstrated to be a continuing point source of mercury (Hg) in the Gulf of Trieste although the Idrija mine was last active in 1996. The present study aims to investigate the role of the suspended particulate matter (SPM) associated with tidal fluxes to disperse particulate Hg (PHg) into the Grado coastal lagoon system. PHg concentrations (avg. 3.11 ± 2.62 μg/g, d.w.), notwithstanding the ebb or flood tides, were significantly higher than the local sediment background (0.13 μg/g). The relative affinity of Hg for the particulate phase in surface waters was confirmed by higher average distribution coefficient (Kd) values (5.6–6.7). PHg contents showed the highest values in ebb tide conditions, thus suggesting their origin from the erosion of tidal flats and saltmarshes of the lagoon. When compared to river discharge, high PHg surface concentrations in flood tide are related to rainfall events occurring within the river basin. Results can be used to make an indicative assessment of the amount of Hg bound to SPM which is transported in and out of the lagoon basin following the action of tidal fluxes. A simple estimation provides a negative budget for the Grado lagoon sub-basin which loses between 0.14 and 1.16 kg of PHg during a tidal semi-cycle. This conclusion is in agreement with the evidence of morphological deterioration which has emerged from recent studies on the lagoon environment, and which testifies to a current sedimentary loss from the lagoon into the northern Adriatic Sea.
Alisè Turritto; Alessandro Acquavita; Annelore Bezzi; Stefano Covelli; Giorgio Fontolan; Elisa Petranich; Raffaella Piani; Simone Pillon. Suspended particulate mercury associated with tidal fluxes in a lagoon environment impacted by cinnabar mining activity (northern Adriatic Sea). Journal of Environmental Sciences 2018, 68, 100 -113.
AMA StyleAlisè Turritto, Alessandro Acquavita, Annelore Bezzi, Stefano Covelli, Giorgio Fontolan, Elisa Petranich, Raffaella Piani, Simone Pillon. Suspended particulate mercury associated with tidal fluxes in a lagoon environment impacted by cinnabar mining activity (northern Adriatic Sea). Journal of Environmental Sciences. 2018; 68 ():100-113.
Chicago/Turabian StyleAlisè Turritto; Alessandro Acquavita; Annelore Bezzi; Stefano Covelli; Giorgio Fontolan; Elisa Petranich; Raffaella Piani; Simone Pillon. 2018. "Suspended particulate mercury associated with tidal fluxes in a lagoon environment impacted by cinnabar mining activity (northern Adriatic Sea)." Journal of Environmental Sciences 68, no. : 100-113.
The Marano and Grado Lagoon is well known for being contaminated by mercury (Hg) from the Idrija mine (Slovenia) and the decommissioned chlor-alkali plant of Torviscosa (Italy). Experimental activities were conducted in a local fish farm to understand Hg cycling at the sediment-water interface. Both diffusive and benthic fluxes were estimated in terms of chemical and physical features. Mercury concentration in sediments (up to 6.81μg/g) showed a slight variability with depth, whereas the highest methylmercury (MeHg) values (up to 10ng/g) were detected in the first centimetres. MeHg seems to be produced and stored in the 2-3cm below the sediment-water interface, where sulphate reducing bacteria activity occurs and hypoxic-anoxic conditions become persistent for days. DMeHg in porewaters varied seasonally (from 0.1 and 17% of dissolved Hg (DHg)) with the highest concentrations in summer. DHg diffusive effluxes higher (up to 444ng/m/day) than those reported in the open lagoon (~95ng/m/day), whereas DMeHg showed influxes in the fish farm (up to -156ng/m/day). The diurnal DHg and DMeHg benthic fluxes were found to be higher than the highest summer values previously reported for the natural lagoon environment. Bottom sediments, especially in anoxic conditions, seem to be a significant source of MeHg in the water column where it eventually accumulates. However, net fluxes considering the daily trend of DHg and DMeHg, indicated possible DMeHg degradation processes. Enhancing water dynamics in the fish farm could mitigate environmental conditions suitable for Hg methylation.
Elisa Petranich; Stefano Covelli; Alessandro Acquavita; Jadran Faganeli; Milena Horvat; Marco Contin. Evaluation of mercury biogeochemical cycling at the sediment–water interface in anthropogenically modified lagoon environments. Journal of Environmental Sciences 2018, 68, 5 -23.
AMA StyleElisa Petranich, Stefano Covelli, Alessandro Acquavita, Jadran Faganeli, Milena Horvat, Marco Contin. Evaluation of mercury biogeochemical cycling at the sediment–water interface in anthropogenically modified lagoon environments. Journal of Environmental Sciences. 2018; 68 ():5-23.
Chicago/Turabian StyleElisa Petranich; Stefano Covelli; Alessandro Acquavita; Jadran Faganeli; Milena Horvat; Marco Contin. 2018. "Evaluation of mercury biogeochemical cycling at the sediment–water interface in anthropogenically modified lagoon environments." Journal of Environmental Sciences 68, no. : 5-23.
Elena Pavoni; Stefano Covelli; Gianpiero Adami; Elena Baracchini; Roberto Cattelan; Matteo Crosera; Pablo Higueras; Davide Lenaz; Elisa Petranich. Mobility and fate of Thallium and other potentially harmful elements in drainage waters from a decommissioned Zn-Pb mine (North-Eastern Italian Alps). Journal of Geochemical Exploration 2018, 188, 1 -10.
AMA StyleElena Pavoni, Stefano Covelli, Gianpiero Adami, Elena Baracchini, Roberto Cattelan, Matteo Crosera, Pablo Higueras, Davide Lenaz, Elisa Petranich. Mobility and fate of Thallium and other potentially harmful elements in drainage waters from a decommissioned Zn-Pb mine (North-Eastern Italian Alps). Journal of Geochemical Exploration. 2018; 188 ():1-10.
Chicago/Turabian StyleElena Pavoni; Stefano Covelli; Gianpiero Adami; Elena Baracchini; Roberto Cattelan; Matteo Crosera; Pablo Higueras; Davide Lenaz; Elisa Petranich. 2018. "Mobility and fate of Thallium and other potentially harmful elements in drainage waters from a decommissioned Zn-Pb mine (North-Eastern Italian Alps)." Journal of Geochemical Exploration 188, no. : 1-10.
Sediments contaminated by Hg and As from two historical mining areas have been deposited in the Nalón estuary (Asturias, northern Spain) since 1850. Total mercury (Hg) concentrations in the sediments range from 0.20 μg g to 1.33 μg g, most of it in the form of sulphides. Concentrations of methylmercury (303.20-865.40 pg g) are up to two orders of magnitude lower than the concentration of Hg. Total As concentration (As) is enriched compared to the background level for the area. The relative abundance of As(V) on As(III) in the sediments ranges from 97.6% to 100%, whereas inorganic Hg accounts for more than 99% of the total Hg. The occurrence of the most toxic species, inorganic As(III) and organic methylmercury, seem to be related to redox conditions together with the amounts of sulphur which act as natural barriers which inhibit the biological and chemical speciation processes. Despite the high amounts of Hg and As present in the sediments, their transference to the water column appear to be limited thus converting sediments in an effective sink of both elements. Special attention should be paid to potential variations of the environmental conditions which might increase the element mobility and exchange between sediments and the water column.
Efrén Garcia-Ordiales; Stefano Covelli; Jose Manuel Rico; Nieves Roqueni; Giorgio Fontolan; Germán Flor Blanco; Pablo Cienfuegos; Jorge Loredo. Occurrence and speciation of arsenic and mercury in estuarine sediments affected by mining activities (Asturias, northern Spain). Chemosphere 2018, 198, 281 -289.
AMA StyleEfrén Garcia-Ordiales, Stefano Covelli, Jose Manuel Rico, Nieves Roqueni, Giorgio Fontolan, Germán Flor Blanco, Pablo Cienfuegos, Jorge Loredo. Occurrence and speciation of arsenic and mercury in estuarine sediments affected by mining activities (Asturias, northern Spain). Chemosphere. 2018; 198 ():281-289.
Chicago/Turabian StyleEfrén Garcia-Ordiales; Stefano Covelli; Jose Manuel Rico; Nieves Roqueni; Giorgio Fontolan; Germán Flor Blanco; Pablo Cienfuegos; Jorge Loredo. 2018. "Occurrence and speciation of arsenic and mercury in estuarine sediments affected by mining activities (Asturias, northern Spain)." Chemosphere 198, no. : 281-289.
This work aims at evaluating mercury (Hg) occurrence, spatial distribution and speciation in groundwater of the Isonzo/Soča River upper alluvial plain downstream from the Idrija Hg mine (Western Slovenia). Several wells and piezometers were sampled both in static and dynamic mode. Total (THg) and filtered (FHg) concentrations were generally higher in static (THg, 1.87–855 ng L−1; FHg, 0.20–13.61 ng L−1) than in dynamic mode (THg, 0.08–78.77 ng L−1; FHg, 0.28–6.65 ng L−1). The estimated background value accounts for 2–3 ng L−1. On the basis of hydrochemistry and isotopic composition, the main sources of groundwater were established. Hg concentrations in the Slovenian sector, supplied by local rainfall, are comparable to values measured close to the Isonzo River. Possible further Hg local sources have been suggested. Stability field analysis for the aqueous Hg species revealed that in the presence of chloride Hg solubility may be increased by the formation of chlorocomplexes. Mercury that rarely enters reduced surrounding conditions can be bound to sulphur to form polysulphide species depending on the pH of water. Since Hg-contaminated alluvial sediments of the Isonzo River may act as a secondary Hg source in groundwater, a borehole was dug down to the water table. Mercury content and speciation revealed that cinnabar (HgS) is the prevalent form followed by the matrix-bound Hg (Hgbound). Variations of the physico-chemical boundary conditions, as well as the raising/lowering of the water table, may be locally responsible for the slight variability of Hg concentrations in the aquifer.
Cerovac Andrea; Covelli Stefano; Emili Andrea; Pavoni Elena; Petranich Elisa; Gregorič Asta; Urbanc Janko; Zavagno Enrico; Zini Luca. Mercury in the unconfined aquifer of the Isonzo/Soča River alluvial plain downstream from the Idrija mining area. Chemosphere 2018, 195, 749 -761.
AMA StyleCerovac Andrea, Covelli Stefano, Emili Andrea, Pavoni Elena, Petranich Elisa, Gregorič Asta, Urbanc Janko, Zavagno Enrico, Zini Luca. Mercury in the unconfined aquifer of the Isonzo/Soča River alluvial plain downstream from the Idrija mining area. Chemosphere. 2018; 195 ():749-761.
Chicago/Turabian StyleCerovac Andrea; Covelli Stefano; Emili Andrea; Pavoni Elena; Petranich Elisa; Gregorič Asta; Urbanc Janko; Zavagno Enrico; Zini Luca. 2018. "Mercury in the unconfined aquifer of the Isonzo/Soča River alluvial plain downstream from the Idrija mining area." Chemosphere 195, no. : 749-761.
The extensive extraction activity of mercury ores in Asturias (northwest Spain), also rich in As and Sb, has impacted the Nalón river estuary. The objective of this research was to assess the historical evolution of As-Hg-Sb accumulation in the salt marsh sediments of this area. For this purpose, sediment cores were collected from two different salt marshes (eastern and western river banks) in the estuarine environment to evaluate the degree of anthropogenic enrichment and the geochronology of As-Hg-Sb accumulation. Core subsampling was performed by cutting 2-cm-thick slices of sediments. The subsamples were then analysed for several physical and chemical parameters. Sedimentation rate was assessed by measuring short-lived radionuclides (excess (210)Pb and (137)Cs). Pre-mining levels of As-Hg-Sb were observed at core depths below 50 cm. In the less extended salt marsh (eastern river bank), maximum As-Hg-Sb concentrations of 87.48, 3.66, and 5.75 μg·g(-1), respectively, were found at the core top as a consequence of long-term mining activity in the area. The vertical distribution of As-Hg-Sb was influenced by the single-point contamination sources, whereas grain-size variability and diagenetic remobilisation did not seem affected. Geochronological measurements showed that the depositional fluxes of As-Hg-Sb were influenced by anthropogenic input after 1900, when mining activity in the area was most intense. Hg mining ceased in 1969; however, the corresponding core profiles did not show a drastic decreasing trend in element fluxes, implying that the river drainage basin retains some "memory" of contamination which affects riverine sediments. A preliminary gross estimation of total As-Hg-Sb "trapped" in the Nalón river salt marsh sediments amounted to approximately 18.7, 1.0, and 0.7 t, respectively. These morphological structures suffer erosive processes, thus representing a potential source of these elements associated with sediments; consequently, management conservation and monitoring of salt marshes should be taken into consideration from this environmental point of view.
Efrén Garcia-Ordiales; Pablo Cienfuegos; Nieves Roqueñí; Stefano Covelli; Germán Flor Blanco; Giorgio Fontolan; Jorge Loredo. Historical accumulation of potentially toxic trace elements resulting from mining activities in estuarine salt marshes sediments of the Asturias coastline (northern Spain). Environmental Science and Pollution Research 2017, 26, 3115 -3128.
AMA StyleEfrén Garcia-Ordiales, Pablo Cienfuegos, Nieves Roqueñí, Stefano Covelli, Germán Flor Blanco, Giorgio Fontolan, Jorge Loredo. Historical accumulation of potentially toxic trace elements resulting from mining activities in estuarine salt marshes sediments of the Asturias coastline (northern Spain). Environmental Science and Pollution Research. 2017; 26 (4):3115-3128.
Chicago/Turabian StyleEfrén Garcia-Ordiales; Pablo Cienfuegos; Nieves Roqueñí; Stefano Covelli; Germán Flor Blanco; Giorgio Fontolan; Jorge Loredo. 2017. "Historical accumulation of potentially toxic trace elements resulting from mining activities in estuarine salt marshes sediments of the Asturias coastline (northern Spain)." Environmental Science and Pollution Research 26, no. 4: 3115-3128.
Mercury (Hg) distribution in saltmarsh sediments and in three selected halophytes (Limonium narbonense, Sarcocornia fruticosa and Atriplex portulacoides) of a wetland system (Marano and Grado Lagoon, Italy) following a contamination gradient in sediments was investigated. The Hg uptake was evaluated at the root system level by calculating the enrichment factor (EF) and in the aboveground tissues by means of the translocation factor (TF). The related methylmercury (MeHg) concentrations in the halophytes were also investigated with regard to the location of the sites and their degree of contamination. Hg concentration in halophytes seemed poorly correlated both with the total Hg in rhizo-sediments and with the specific plant considered, supporting the evidence that the chemico-physical parameters of sediments could significantly affect metal availability for plants. Hg concentrations in roots increased with depth and were 20-fold higher than content measured in related rhizo-sediments (high EF). A low content of Hg is translocated in aboveground tissues (very low TF values), thus highlighting a kind of avoidance strategy of these halophytes against Hg toxicity. MeHg values were comparable between the two sites and among species, but the translocation from below- to aboveground plant tissues was more active.
Elisa Pellegrini; E. Petranich; A. Acquavita; João Canário; A. Emili; S. Covelli. Mercury uptake by halophytes in response to a long-term contamination in coastal wetland salt marshes (northern Adriatic Sea). Environmental Geochemistry and Health 2017, 39, 1273 -1289.
AMA StyleElisa Pellegrini, E. Petranich, A. Acquavita, João Canário, A. Emili, S. Covelli. Mercury uptake by halophytes in response to a long-term contamination in coastal wetland salt marshes (northern Adriatic Sea). Environmental Geochemistry and Health. 2017; 39 (6):1273-1289.
Chicago/Turabian StyleElisa Pellegrini; E. Petranich; A. Acquavita; João Canário; A. Emili; S. Covelli. 2017. "Mercury uptake by halophytes in response to a long-term contamination in coastal wetland salt marshes (northern Adriatic Sea)." Environmental Geochemistry and Health 39, no. 6: 1273-1289.
The mineral body exploited in Salafossa (Eastern Dolomites) was one of the largest lead/zinc-containing mineral deposits in Europe. Both metals were mainly present as sulphides (sphalerite, ZnS and galena, PbS). Mining activity started around 1550, but it was only around 1960 that the richest veins of the minerals were discovered. The mine closed in 1985, and concentrations of several trace metals, such as thallium (Tl), iron (Fe), manganese (Mn), lead (Pb) and zinc (Zn), were detected in the soils and plant samples (Biscutella laevigata L.) that were collected from eighteen sites selected outside the mine. B. laevigata is a pseudometallophyta species, and it often grows near mining areas where the soil's metal concentrations are significantly higher than those of soil with a natural geochemical background. The total metal concentrations in the plant tissue (roots and leaves of Biscutella laevigata) and in the soil samples - both bulk-soil and the B. laevigata root system (rhizo-soil) - were determined through Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES). The metal extractability and leachability of the soil samples were estimated using soil extractions with DTPA (Diethylenetriaminepentaacetic acid). In addition, metal mobility caused by rainwater runoff was estimated by using a leaching test with a dilute solution of HSO and HNO. The results showed that metals were present in a chemical form available for uptake by the plants' roots. In fact, high concentrations of the metals were also found in the plant tissue (roots and leaves) of B. laevigata, and these concentrations were higher than those whose soils present natural geochemical background levels in the corresponding rhizo-soil. Thus, B. laevigata has shown a marked ability to bioaccumulate trace metals, especially Tl and, to a lesser extent, Zn, Pb, Fe and Mn, and it can influence metal mobility in the rhizo-soil. To assess the uptake and translocation processes of the trace metals, resulting in their bioaccumulation, two different indices were calculated: the enrichment factor in roots (EFr), as the ratio between the metal concentration in belowground biomass and in the respective rhizo-soil, and the translocation factor (TF), as the ratio between the metal concentration in the leaves and the corresponding roots. For both indices, values > 1 denoted enrichment of the metal in the roots or its translocation to the upper tissues. The results showed that EFr and TF were considerably high only for Tl, reaching a maximum value of 60 for EFr and 11.6 for TF. Conversely, the other investigated metals did not show significant bioaccumulation (EFr < 1), and they showed TF > 1 only at a few sites.
Elena Pavoni; Elisa Petranich; Gianpiero Adami; Elena Baracchini; Matteo Crosera; Andrea Emili; Davide Lenaz; Pablo Higueras; Stefano Covelli. Bioaccumulation of thallium and other trace metals in Biscutella laevigata nearby a decommissioned zinc-lead mine (Northeastern Italian Alps). Journal of Environmental Management 2017, 186, 214 -224.
AMA StyleElena Pavoni, Elisa Petranich, Gianpiero Adami, Elena Baracchini, Matteo Crosera, Andrea Emili, Davide Lenaz, Pablo Higueras, Stefano Covelli. Bioaccumulation of thallium and other trace metals in Biscutella laevigata nearby a decommissioned zinc-lead mine (Northeastern Italian Alps). Journal of Environmental Management. 2017; 186 ():214-224.
Chicago/Turabian StyleElena Pavoni; Elisa Petranich; Gianpiero Adami; Elena Baracchini; Matteo Crosera; Andrea Emili; Davide Lenaz; Pablo Higueras; Stefano Covelli. 2017. "Bioaccumulation of thallium and other trace metals in Biscutella laevigata nearby a decommissioned zinc-lead mine (Northeastern Italian Alps)." Journal of Environmental Management 186, no. : 214-224.
Previous research conducted in the Marano and Grado lagoon (northern Adriatic Sea) has shown that this environment has been affected by trace metal contamination, especially by mercury (Hg), from both industrial (the chlor-alkali plant) and mining activities (Idrija mine, Slovenia). Sediment cores were collected from two different saltmarshes of this lagoon environment to evaluate the degree of the anthropogenic enrichments and the geochronology of Hg accumulation. Core subsampling was performed by cutting 1-cm thick slices at discrete intervals. Mercury determination was done differently from the other parameters in that the two long cores were subsampled at 1-cm intervals to obtain continuous concentration profiles. Samples were completely decomposed, using a mixture of mineral acids in a closed microwave system before being analysed for trace metal content using ICP-OES. Total Hg content in the solid phase was determined by DMA-80. 137Cs was measured via gamma spectrometry. 210Pb activity was measured via alpha-counting of its daughter, 210Po, assuming secular equilibrium between the two isotopes. In saltmarsh sediments, Fe, Co, Li, Sc and V show no enrichment at both sites thus suggesting that they are essentially lithogenic elements. Conversely, enrichments are minimal (EF = <2) for As, Cd, Cr, Ni, Pb and Zn and moderate (EF = 2–5) for Cu and Mn and also for Pb and Zn but only in some levels of the sedimentary sequences. An exception is Hg, as expected due to the long-term input proceeding from the historical mining activity which has especially affected the eastern sector of the lagoon. The core collected from the saltmarsh in the eastern lagoon (Grado) displays a better time resolution during the last century although the Hg background level has not been reached. Conversely, the core collected in the western sector (Marano) has recorded a longer and more complete history of Hg contamination, from the beginning of the peak of Hg extraction activity at the Idrija mine (1850). Both saltmarshes still receive Hg inputs and the sediment accumulation rates in the upper section appear to have increased over the last 10–20 years (from 0.30 to 0.45 cm year−1 at Marano and from 0.30 to 0.74 cm year−1 at Grado). Many of these morphological structures suffer erosive processes thus representing a potential source of contaminants associated with sediments, in particular Hg. Conservation and monitoring of saltmarshes should be taken into consideration also from this environmental point of view.
Stefano Covelli; Elisa Petranich; Leonardo Langone; Andrea Emili; Alessandro Acquavita. Historical sedimentary trends of mercury and other trace elements from two saltmarshes of the Marano and Grado lagoon (northern Adriatic Sea). Journal of Soils and Sediments 2016, 17, 1972 -1985.
AMA StyleStefano Covelli, Elisa Petranich, Leonardo Langone, Andrea Emili, Alessandro Acquavita. Historical sedimentary trends of mercury and other trace elements from two saltmarshes of the Marano and Grado lagoon (northern Adriatic Sea). Journal of Soils and Sediments. 2016; 17 (7):1972-1985.
Chicago/Turabian StyleStefano Covelli; Elisa Petranich; Leonardo Langone; Andrea Emili; Alessandro Acquavita. 2016. "Historical sedimentary trends of mercury and other trace elements from two saltmarshes of the Marano and Grado lagoon (northern Adriatic Sea)." Journal of Soils and Sediments 17, no. 7: 1972-1985.