Chemistry, mineralogy and radioactivity in posidonia oceanica meadows from North-Western Sicily (original) (raw)
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Mediterranean Marine Science, 2013
Distribution of metals (Hg, Pb, Sn, Cu, Cd and Zn) was determined in sediments and in different tissues of Posidonia oceanica collected from San Pietro Island, Taranto Gulf (Ionian Sea, Southern Italy). In seagrass, results, compared with metal concentrations in sediments, showed that the highest concentrations of Hg, Pb, Sn and Cu were found in the roots, while in the green leaves were found the highest levels of Cd and Zn. Instead the lowest metal concentrations were found in the basal part of the leaf. Levels of metals in the leaves were similar to those found by other authors in uncontaminated areas of the Mediterranean Sea. Mercury levels in roots were correlated to levels in sediments. This could demonstrate the plant memorizes sediments contamination . This study reinforces the usefulness and the relevance of Posidonia oceanica as an indicator of spatial metal contamination and an interesting tool for environmental quality evaluation.
Distribution of heavy metals in the Piscinas beach sediments (SW Sardinia, Italy)
Environmental Geology, 1999
We have studied sediments of the Piscinas beach (SW Sardinia, Italy), which is supplied by two streams that wash mine dumps of abandoned lead and zinc mines at Montevecchio and Ingurtosu, situated inland from the supply basin of the beach itself. A study of the texture, mineralogy and geochemistry of the sediments was conducted for the purpose of assessing the possible influence of the mine waste on the composition of the sediments, looking for any anomalous enrichments in heavy metals. Furthermore, to evaluate and quantify metal release into the sea, samples of Posidonia oceanica, a bioaccumulator marine plant, were also examined. The results indicate that the distribution of heavy metals in the foreshore sediments is particularly affected by the contribution of the streams, while in the shoreface the distribution is affected by the currents that disperse the sediments both out to sea and southwards. The metal contents of the Posidonia oceanica are correlated with the different stages of activity of the mines.
Environmental Monitoring and Assessment, 2016
The Mediterranean endemic seagrass Posidonia oceanica is widely used as a sensitive bioindicator of trace elements (TEs) in the coastal environment. Therefore, a bulk of data exist on TE levels from impacted versus unpolluted sites while only recent studies started comparing TE accumulation in plant compartments versus both water column and sediment characteristics. In this study, six TEs (As, Cd, Cr, Cu, Ni, Pb) were analyzed in P. oceanica shoots related to depth (−10 and −20 m) and to TE concentrations in the different grain size fractions of the sediment, from two Sites of Community interest (SIC) in the central Tyrrhenian Sea. TE concentrations in both shoots and sediment were generally low, except for Cr. Cu was the only element showing significantly different concentrations at the two sites while As differed significantly between samples taken at different depths. TE concentrations in the unsieved sediment were found uncorrelated to TEs in shoots except for the important nutrient Cu (positive correlation). The finest sediment fractions were enriched in TEs and significantly correlated to Cd, Cr, Cu, and Ni concentrations in the shoots. Keywords Trace elements. Sediment grain size fractions. Bioaccumulation. Tyrrhenian Sea Background The environmental quality of coastal habitats of the Mediterranean Sea is seriously challenged by a plethora of anthropogenic impacts resulting from the multiple and conflicting use of coasts, urbanization, industrialization, mining, waste disposal, aquaculture, tourism, or transports (Micheli et al. 2013). One of the consequences of these activities is the chemical contamination by trace elements (TEs), which are both toxic and persistent, hence accumulating in marine living organisms along their life cycle and so entering the food chain (Nixon and Fulweiler 2009). For this reason, trace elements are regarded as dangerous pollutants and some of them such as Cd, Pb, Hg, and Ni are listed as priority substances in the European Environmental Quality Standard Directive (EQSD 2008/105/EC) and subject to control under several directives and regulations. An effective monitoring of trace element concentrations is therefore essential and has required the identification of reliable bioindicators responding to the concentration and bioavailability of elements present in the marine waters and soil (Costanza et al. 1997). Among the
J. Environ. Monit., 2012
The use of biological species in the monitoring of marine environmental quality allows the evaluation of biologically available levels of contaminants in the ecosystem and the effects of contaminants on living organisms. The seagrass Posidonia oceanica is a useful bioindicator because through the lepidochronology technique it is possible to obtain a historical contamination trend of a given area. This study aims to assess the temporal trend contamination by heavy metal investigations on dead sheaths of 100 samples of P. oceanica collected in the Protected Marine Area of ''Plemmirio'' (Sicily) and in the Siracusa bay. Important results were obtained because data show a significant negative temporal trend for the metals analysed especially for As, Co, Cr, Hg, Pb, Se, U and V that in the past had higher concentrations, with a stronger contamination in the Plemmirio area, the site much more exposed to the pollution of the nearby petrochemical complex. This study confirms the relevance of the use of P. oceanica as a biological indicator of metal contamination in coastal ecosystems. Thus the usefulness of P. oceanica as a tracer of spatial metal contamination and as a good tool for water quality evaluation is reinforced.
2004
Levels of Hg, Cd, Pb, Cu, Zn, Fe, and Mn were assessed by using Posidonia oceanica as a bioindicator in the Gulf of Naples (southern Italy). Lepidochronology, which enables retroactive dating of scales and rhizomes of this seagrass, was combined with atomic spectrometry to assess temporal trends of trace elements in dated scales and rhizomes over a 10-year period. Lepidochronology occasionally has been used to monitor Hg in dated scales, but never has been used to determine concentrations of other trace elements in dated rhizomes. Data were compared between various structural parts of seagrass and between sampling sites. Concentrations of some elements found in dated scales or rhizomes showed a similar trend in most of the sites; increasing for Hg and Cu and decreasing for Pb, Fe, and Zn. Contaminant levels indicated by seagrass meadows varied from metal to metal. Concentrations of Hg, Cd, and Pb fell within the ranges measured in other areas considered to have low levels of heavy metal pollution, whereas Cu, Mn, and Zn had higher concentrations only in some years. However, on the basis of other studies, none of the sampling sites are considered to have high contamination levels.
Heavy Metals in Marine Sediments from the Mar Piccolo of Taranto (Ionian Sea, Southern Italy
Annali Di Chimica, 2006
Heavy metals concentrations (Cd, Cu, Hg, Pb, Sn and Zn) have been determined monthly in surface sediments from the Mar Piccolo in Taranto (Ionian Sea, Southern Italy. a semi-enclosed marine basin very important from a mussel-culture point of view. In sediments, sulphides, percentage of organic carbon and redox potential were also determined to show possible correlations between metals levels and redox characteristics of marine sediments. Analytical results, elaborated by multivariate statistical techniques, confirm that sediments collected in the first inlet of Mar Piccolo, where shipbuilding activities are present, have a contamination level greater than those collected in the second inlet. For each metal, the geoaccumulation index (Igeo) has been calculated as criterion to evaluate both pollution levels and metals enrichment in examined sediments: Igeo values confirm that the first inlet is an moderately polluted area from Hg and Pb. In any case, high sulphide concentrations and negative values of redox potentials bring to a conclusion that metals are present in sediments, mainly as insoluble sulphides and then as not bioavailable compounds for filter feeders organisms such as mussels.
Heavy metals in sediments from different environments of a northern Adriatic Sea area, Italy
Environmental Geology and Water Sciences, 1984
Sediments from different environments of an area di-rectly affected by the discharge of the Po River and 13 other minor rivers have been studied Three main sources of metals and several distribution mechanisms can be identified Concentration profiles of metals in a core allow one to establish background levels of finegrained sediments for Cd, Hg, Pb, and Zn Seabed sediments do not appear to be very polluted, mainly because of desorption and dilution processes
Seagrasses appear relevant bioindicators of metallic contamination in coastal waters. Posidonia oceanica leaves were collected at six locations along the north and east coast of the Adriatic Sea selected on the basis of the presence of different types and levels of human-induced pressures. Concentration of seven trace-metals (Ag, As, Cd, Cu, Hg, Ni and Pb), as well as the Methyl-Mercury content, were determined. The level of contamination is low at the pristine site of Lavdara (Cu: 4.73 ± 0.01 μg/g; Hg: 0.054 ± 0.003 μg/g; Met-Hg: 0.015 ± 0.000 μg/g; Ni: 21.40 ± 0.63 μg/g; Pb: 0.90 ± 0.10 μg/g) and higher along the Slovenian coast (Cu: 11.83 ± 0.22 μg/g, Hg : 0.092 ± 0.004 μg/g ; Met-Hg: 0.027 ± 0.004 μg/g; Ni: 40.07 ± 2.08 μg/g, Pb: 1.50 ± 0.06 μg/g). Generally, Mercury and the associated trace metals contents are relatively high in P. oceanica collected in the Northern Adriatic region. This is due not only to the strong anthropogenic impact (ports of Trieste and Koper, former chloralkaline plant-PVC near Seget Donji) but also to the geological characteristics of the hinterland (former cinnabar ore in Slovenia). This preliminary study confirms the capability of P. oceanica to record trace metal in relation with humaninduced pressures, as well as with geological background of the coast.
Water, Air, & Soil Pollution, 2011
The Mar Piccolo (surface area of 20.72 km 2) is located in the Northern area of the Taranto town (Ionian Sea, Italy). It is an inner, semi-enclosed basin with lagoon features connected with the Mar Grande through two channels which are very important for water exchange. Mar Piccolo basin is subjected to urbanization, industry, agriculture, aquaculture and commercial fishing. Hence, it is important to have a temporal picture both of heavy metal content and of organic carbon and their distribution (hydrophobic fraction, hydrophilic fraction, humic compounds) to check the progress of pollution in time. Three sediment cores collected on the basis of the pollution sources have been analyzed. Both heavy metal and organic carbon concentrations underline the fact that the anthropogenic input is different in the three sites, and that in time the amount of pollutants coming into the Mar Piccolo have changed in different ways. The high amount of organic hydrophilic compounds present in sediments, both due to the small water depth and to the high accumulation rate, make the sediment site high in oxygen consumption due to a considerable chemical and biochemical transformations of organic matter.