The presence of potentially toxic elements (PTE) was determined in different tissues of five selected marine organisms. The As, Cd, Cu, Mn, Mo, Ni, Pb and Zn concentrations were measured in the ...seagrass Cymodocea nodosa, the green alga Cladophora echinus, the red alga Gelidiella lubrica, the marine topshell Phorcus turbinatus and the littoral crab Carcinus aestuarii, as well as in seawater from Makirina Bay. The levels of As, Cd, Cu, Mn and Zn in the biota were found to exceed those in previously analysed sediments, indicating the bioaccumulation of these PTE. The biota-sediment accumulation factor (BSAF) and concentration factor (CF) varied among different organisms. As regards the five selected species, C. nodosa, C. echinus and G. lubrica proved to be the strongest accumulators of Mn, while P. turbinatus and C. aestuarii showed a high capacity to accumulate As, Cd, Cu and Zn. These species can be considered as good ecological indicators in the assessment of PTE pollution in marine littoral environments.
This study concerns the microfacies characterization of white and black limestone tesserae from selected Roman floor mosaics in Slovenia, with the aim of defining their provenance. We investigated 42 ...tesserae from 15 different mosaics from the archaeological sites of Ljubljana, Izola, Mošnje, Ptuj, Črnomelj and Šentpavel, dated from the first century bc to the fifth century ad. Among the studied tesserae, 13 different microfacies were identified: eight black and five white. The most common were mudstones with ostracods (65% of black tesserae) and wacke‐packstones with miliolids (85% of white tesserae). The majority of the identified facies can be found in the Cretaceous successions of the Dinaric Carbonate Platform in south‐western Slovenia, north‐eastern Italy and south‐eastern Croatia, suggesting a regional or imported origin of the tesserae.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Mining is very important economic activity. However, mining and related industries presents the main threat for environment. Pollution with heavy metals is a significant problem in Eastern Republic ...of Macedonia. In year 2003 great environmental disaster happened near small town Makedonska Kamenica, when the Sasa tailings dam collapsed and caused an intensive flow of mining waste material through Kamenica River valley and was discharged into Lake Klaimanci. Water from lake is used for irrigation, thus, the pollution assessment of the Lake Kalimanci sediments was made. The major, trace and rare earth element contamination in surficial lake sediments was studied to assess the effects of metalliferous mining activities. The mean concentrations of major elements wt % Si 23.5, Al 7.9, Fe 6.6, Mg 1.3, Ca 3.8, Na 1.1, K 2.3, Ti 0.4, P 0.2, Mn 0.6 and trace elements ranged within: Mo 1.0-4.6 mg kg-1, Cu 144.4-1162 mg kg-1, Pb 1874-16300 mg kg-1, Zn 2944-20900 mg kg-1, Ni 21.7-79.3 mg kg-1, Cd 16.5-136 mg kg-1, Sb 0.6-3.6 mg kg-1, Bi 3.0-24,3 mg kg-1 and Ag 1.4-17.3 mg kg-1. Results of rare earth elements (REE) in surficial lake sediments indicated that are tightly related to the catchment geology. The results of the sequential extraction procedure revealed the majority (Cd, Zn, Pb, Ni, Cu and Cd) of investigated toxic metals and all REEs to be strongly bonded to the exchangeable fraction and the rest (As and Mo) to the oxidizable fraction. Regarding to results is evident that heavy metals and REEs are highly bioavailable for living organisms and can seriously affect human health.
The aim of the present study was to determine the concentrations of several potentially toxic elements (PTE) in the recent marine sediment of Makirina bay (central Adriatic), which could according to ...its organoleptic properties be used as a virgin material for medical treatment, wellness and relax purposes. Sediment samples were collected in June and July 2010 from six different sites in the central part of the bay. The range of measured elemental concentrations in analysed surficial sediment were: As (11-15,8 ppm), Cr (61,6 -109,5 ppm), Cu (19,4-54,2 ppm), Pb (16,8-29,6 ppm) and Zn (37-52 ppm). Sediment PTE pollution assessment was performed using contamination factor (CF), contamination degree (Cdeg) and pollution load index (PLI). The calculated environmental index values show a low to moderate contamination status of sediment. Future geochemical investigation on these sediments are necessary prior actual use in various therapeutic treatment.
The aim of this study was to determine the levels of potentially toxic elements in cultured and wild fish tissues and to assess their risk for human health. For this purpose, sea bass specimens ...(Dicentrarchus labrax) were sampled in selected fish farm and three other locations along the eastern Adriatic coast. Ranges of element concentrations in sea bass muscles were 1.60-4.46 ppm for As, 0.001-0.079 ppm for Cd, 0.14-49.10 ppm for Cr, 1.38-4.85 ppm for Cu, 0.11-1.31 ppm for Hg, 0.01-0.65 ppm for Pb and 21.9-136.0 ppm for Zn. Mean Cd, Cr, Cu, Hg, Pb, and Zn concentrations in commercially interesting cultured fish samples were below the permissible levels, while mean As values slightly exceed those limits. In wild fishes mean Cd, Cu, Pb and Zn concentrations were below the recommended limits, for As, Cr and Hg the mean values were higher. The smallest cultured sea bass samples showed As, Cr, Pb, and Zn concentrations exceeding the recommended limits but values decreased with fish size. Therefore, the metal concentrations in commercial fishes showed no threat for human consumption.
In the frame of this work, Al-5Ni-1Co-3RE (RE-Rare Earth (Mischmetal)) rapidly solidified ribbons were manufactured and analyzed. The morphology of the as-cast structure, as well as the ...microstructural features were analyzed by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Thermal stability has been investigated by combination of four point scanning electrical resistivity measurement (ER), differential scanning calorimetry (DSC) and microhardness measurement. From the results we can conclude, that Al-5Ni-1Co-3RE rapidly solidified alloys have good thermal stability due to very slow coarsening kinetics of precipitated particles.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
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•Weathered coal ash landfills exhibit pH decrease and formation of secondary minerals.•High sulfur content in CCR impedes pedogenesis and limits plant growth.•The presence of ...montmorillonite accelerates pedogenesis.•Particle properties such as SSA and CEC change with pedogenesis in coal ash landfills.•13C NMR spectra point to the unburned coal particles as the main origin of organic matter.
Coal combustion has been one of the most dominant sources of energy for the last two centuries, generating tonnes of coal combustion residue (CCR). Rapid soil formation has been observed at old CCR disposal sites, altering the physiochemical and mineral properties of CCR, affecting contaminant release mechanisms and nutrient availability. Although ubiquitous, pedological properties of weathered CCR have been studied at only a small number of disposal sites. This study characterized two CCR landfills of similar age (∼50 years) using a range of parameters, including pH, total nitrogen and organic carbon content, major oxides (Al2O3, CaO, and SiO2), and macronutrients (Ca, K, Mg, P, and S), as well as textural and mineralogical data. In addition, specific surface area and cation exchange capacity were determined to assess particle properties, and 13C and 29Si NMR spectra were examined to characterize the organic matter and degree of polymerization of the coal ash glassy phase. Such comprehensive approach aimed to determine indicators of soil formation and to characterize the capacity of such landfills to retain water, nutrients, and contaminants. Both landfills displayed evidence of pedogenesis reflected in the pH decrease, formation of secondary minerals (such as ettringite, hydrotalcite, gypsum, and calcite), and changes in the C:N ratio. The Plaški landfill seems to have a better capacity to hold water, nutrients, and contaminants evident by higher clay content, CEC, and SSA values, possibly explaining why it developed more rapidly than Štrmac despite their similar age. The presence of montmorillonite in Plaški could be one of the main factors accelerating pedogenesis. 13C NMR spectra point to the unburned coal particles as the main origin of organic matter and 29Si NMR spectra showed higher depolymerization of a non-crystalline fraction in bare ash samples than in vegetated ash samples.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Information on aquaculture-related environmental impact along the eastern Adriatic coast is very scarce. In this paper, the area affected by fish farm and sewage derived particulate nitrogen in the ...Murter Sea and semi-enclosed Pirovac Bay (central Adriatic, Croatia) was assessed using the stable nitrogen isotopic composition (
δ
15N) in particulate organic matter (POM) and benthic sessile invertebrates (
Aplysina aerophoba,
Balanus perforatus and
Anemonia sulcata) in the exposed areas compared to an unpolluted reference site. The results suggest that increased
δ
15N values in the POM and biota in the impacted areas are predominantly due to nitrogen losses through feed wastage and fish excretion (faeces), but also due to the sewage discharge into the marine coastal ecosystems. The
δ
15N values of the selected organisms were significantly higher around fish cages, as well as at sites polluted by urban waste, compared to the reference site and some other pristine offshore locations. The
15N enrichments of
A. aerophoba,
A. sulcata and
B. perforatus collected around fish cages compared to the reference location were up to 6.8, 6.5 and 5.2‰, respectively, which exceeds the natural variability. While the
δ
15N values of
A. sulcata and
B. perforatus showed an excellent linear correlation with those of the POM, a weaker correlation was found between
δ
15N of
A. aerophoba and the POM, although its
δ
15N values consistently increased with the increased
δ
15N values of POM. This is attributed to the presence of different bacterial populations hosting in the sponge. A geochemical map of the
δ
15N values in the POM and organisms was created, which could be used for tracing the dispersion of
15N loading generated by aquaculture and sewage in the receiving environment, and their transfer into biota in the adjacent coastal ecosystem. Sponges or other organisms, although known as non-selective suspension feeders, but hosting abundant bacterial populations, may have
δ
15N values lower than the POM, but still reflecting the overall enrichment of the environment in
15N due to the presence of enriched effluents from aquaculture operation or municipal discharges.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
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