Partitioning of heavy metals in different particle-size fractions of soils from former mining and smelting locations in Austria

Abstract

Austrian soils from mainly historical mining and smelting sites were separated into four particle size fractions (coarse sand, fine sand, silt and clay) to distinguish the possible origins and pathways of heavy metals. Each fraction was extracted with aqua regia to determine the pseudo-total content and with CaCl2 to determine the available content of metals. The soil mineralogical composition of the < 2000 µm fraction was determined by X-ray diffraction (XRD). In general, the concentration of heavy metals and metalloids increased as soil particle size decreased. Based on the correlations of concentrations vs. the log of the mean particle size, obtained from each fraction the presence of unweathered allochthonous minerals were especially present in samples from locations at Rabenstein for most trace elements, at Arzwaldgraben for Cd, Co, Mn and Pb, at Johnsbach for Cd, Co, Mn, Pb and Zn and at Pilgersdorf for Cr. The opposite trend was found for the samples of the industrial area of Arnoldstein, Zeltweg and Hinterlobming suggesting that their metal load was derived from the discharge of effluents or from weathered phases.

Biogeomorphic recovery of a river reach affected by mining

“…Sediments on exposed weathered surfaces show lower levels of contamination, whilst differences between levels observed in unvegetated active channel sediments and vegetated floodplain sediments are likely to be more a reflection of differences in the finest size fractions of the samples (e.g. Bradley, 1989; Jelecevic et al, 2021; Lewin et al, 1977). There is, however, no clear correlation between vegetation type and contamination levels.…”

“…The samples were analysed by X-ray fluorescence (XRF) using a Thermo Scientific Nitron XL3t instrument. Each sample was air-dried, sieved to <2 mm, homogenized and then analysed for 240 s following Caporale et al (2018) and Jelecevic et al (2021). Three analyses were performed on each sample and the results were averaged.…”

The Potential Roles of Biochar in Restoring Heavy-Metal-Polluted Tropical Soils and Plant Growth

“…Since it is reported to have high cation exchange capacity and high effect on soil pH [18,35,36], biochar was shown to improve the above agronomic responses of thorny amaranth (Figures 11 and 12). The presence of biochar may have increased the soil adsorption capacity and lowered the soil labile fractions of Cu and Zn, thereby alleviating their phytotoxicities and finally stimulating the plant growth.…”

Past Metal(loid) Pollution Records Inferred from the Sediments of Bukit Merah Reservoir Perak, Malaysia

“…Sediment grain size distribution affects the concentrations of contaminants per unit of sediment mass owing to the greater surface area to mass ratio of fine-grained sediments [68]. Changes in particle grain size distribution with depth in the sediment cores may influence the contamination level in the sediment core [69]. However, in our study, the fine grain fraction (63 microns) was not significant (p<0.05) in determining the concentration of heavy metals in the sediment core of BMR.…”