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BoroviCka J.,Nuclear Physics Institute of Czech Republic | BoroviCka J.,Academy of Sciences of the Czech Republic | Kotrba P.,Institute of Chemical Technology Prague | Gryndler M.,Academy of Sciences of the Czech Republic | And 6 more authors.
Science of the Total Environment | Year: 2010

Macrofungi are effective accumulators of Ag. This study provides a comprehensive review of this phenomenon supported by original data on the Ag concentrations of macrofungi from pristine and Ag-polluted areas. In pristine areas, the median Ag concentrations of ectomycorrhizal (ECM) and saprobic (SAP) macrofungi were 0.79 and 2.94mgkg-1, respectively. In these areas, hyperaccumulation thresholds for Ag in ECM and SAP macrofungi are proposed as 100 and 300mgkg-1, respectively. In a Ag-polluted area, the Ag concentrations in macrofungi (ECM and SAP) were significantly elevated with the median value of 24.7mgkg-1 and the highest concentrations in Amanita spp. of the section Vaginatae (304-692mgkg-1). The intracellular speciation of Ag in fruit-bodies of the Ag-accumulator Amanita submembranacea was inspected by size exclusion chromatography followed by sulfhydryl-specific fluorimetric assays of ligands using reverse phase high-performance liquid chromatography and improved polyacrylamide gel electrophoresis. Virtually all Ag was found to be intracellular and sequestered in the major 7kDa and minor 3.3kDa complexes. The lack of glutathione and phytochelatins and the presence of a single 3kDa sulfhydryl-containing peptide in the isolated Ag-complexes suggest that detoxification of Ag in A. submembranacea may rely on metallothionein. Vertical distribution of Ag in a polluted forest soil profile has shown substantial enrichment in organic horizons; in polluted technosol, the highest Ag concentrations were found in surface layers. Standardized EDTA extraction of Ag in both the investigated soil profiles showed relatively low Ag extractibility, generally within the range of 2.2-7.7% of total Ag content. © 2010 Elsevier B.V. Source


Kubrova J.,Charles University | Kubrova J.,Nuclear Physics Institute of Czech Republic | Zigova A.,Academy of Sciences of the Czech Republic | Randa Z.,Nuclear Physics Institute of Czech Republic | And 7 more authors.
Journal of Hazardous Materials | Year: 2014

Interactions of macrofungi with U, Th, Pb and Ag were investigated in the former ore mining district of Příbram, Czech Republic. Samples of saprotrophic (34 samples, 24 species) and ectomycorrhizal (38 samples, 26 species) macrofungi were collected from a U-polluted Norway spruce plantation and tailings and analyzed for metal content. In contrast to Ag, which was highly accumulated in fruit-bodies, concentrations of U generally did not exceed 3. mg/kg which indicates a very low uptake rate and efficient exclusion of U from macrofungi. In ectomycorrhizal tips (mostly determined to species level by DNA sequencing), U contents were practically identical with those of the non-mycorrhizal fine spruce roots. These findings suggest a very limited role of macrofungi in uptake and biotransformation of U in polluted forest soils. Furthermore, accumulation of U, Th, Pb and Ag in macrofungal fruit-bodies apparently does not depend on total content and chemical fractionation of these metals in soils (tested by the BCR sequential extraction in this study). © 2014 Elsevier B.V. Source


Kyser K.,Queens University | Lahusen L.,Uravan Minerals Inc. | Drever G.,Houston Lake Mining | Dunn C.,8756 Pender Park Drive | And 2 more authors.
Comptes Rendus - Geoscience | Year: 2015

The response in elemental concentrations and Pb isotopes in various surface media from the Cigar West unconformity-type uranium deposit located at a depth of 450m were measured to ascertain if element migration from the deposit can be detected at the surface. The media included clay-size fractions separated from the A2, B and C soil horizons, and tree cores and twigs from black spruce (Picea mariana) and jack pine (Pinus banksiana) trees. Lead isotopes were used to trace any effect on the surface media from the deposit at depth because the 207Pb/206Pb ratios in the ore are<0.1, whereas the background values in the basin are>0.7 and modern anthropogenic Pb from aerosols are near 0.9. The tree cores record their lowest and therefore most radiogenic 207Pb/206Pb ratios of<0.7 near the surface projection of the deposit and associated structures, particularly in tree rings that predate any exploration and drilling activity in the area. The median 207Pb/206Pb ratios increase in the order C, B soil horizon clays, tree cores, A2 soil clays and twigs because of the increasing contribution of common Pb with high ratios from anthropogenic sources that affect the shallowest media the most. Although this anthropogenic Pb as well as that from the background dominates the composition of all media at the surface and the contribution from the deposit at depth is diminished toward the surface, ore-related Pb is still present as a few percent of the composition of pathfinder elements and Pb isotopes. © 2015 Académie des sciences. Source


Borovicka J.,Academy of Sciences of the Czech Republic | Borovicka J.,Nuclear Physics Institute of Czech Republic | Dunn C.E.,8756 Pender Park Drive | Gryndler M.,Academy of Sciences of the Czech Republic | And 5 more authors.
Soil Biology and Biochemistry | Year: 2010

Samples of macrofungi collected in the vicinity of the Mokrsko gold deposit were analyzed for Au by INAA and ICP-MS. Ectomycorrhizal fungi yielded from 0.88 to 564 μg kg-1 Au (dry weight) in 79 samples. Saprobic fungi (75 samples) from the same locations yielded significantly higher concentrations: 3-7739 μg kg-1 Au (dry weight), with the highest contents in Lycoperdon perlatum. These are the highest recorded concentrations of Au in naturally-occurring fungi/vascular plants. Concentrations of Au in ectomycorrhizae were approximately 4-10 times higher than those in fine roots. It appears that saprobic fungi, namely several terrestrial saprobes of the genera Agaricus and Lycoperdon, are more efficient than ectomycorrhizal fungi at taking up Au, probably assisted by other microbiota and/or by a range of naturally-occurring compounds that have yet to be identified. The present data demonstrate that macrofungi are involved in the biogeochemical cycling of Au. © 2009 Elsevier Ltd. All rights reserved. Source

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