| Autor: |
JURKOVIČ, ĽUBOMÍR, JUHÁSOVÁ, JANA, KULIKOVA, TATIANA, FARAGÓ, TOMÁŠ, MÉRES, ŠTEFAN, KLIMKO, TOMÁŠ, ŠOTTNÍK, PETER, HILLER, EDGAR, NEMČEK, LUCIA, BUJDOŠ, MAREK |
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| Zdroj: |
Mineralia Slovaca; 2019, Vol. 51 Issue 2, p217-232, 16p |
| Abstrakt: |
One of the most important sources of soil contamination with metals and metalloids is mining and processing of mined ores. Old tailing ponds and dumps affect the surrounding environment mainly by releasing potentially toxic trace elements, and thus contribute to contamination of the natural environment, including soils. The area of abandoned antimony deposit Čučma (eastern Slovakia) with unliquidated and unsecured mining wastes belongs to environmental burden, which should be monitored and eventually remediated. The main objective of this article was to (i) determine the basic physicochemical properties of mining soils at the former Čučma antimony deposit and total concentrations of selected trace elements with the emphasis on antimony (Sb) and arsenic (As), (ii) characterize mineralogy of these soils and (iii) evaluate the mobility of the two metalloids by means of extraction experiments with distilled water. The soils of the former antimony deposit Čučma showed a wide range of pH values (2.84 - 7.45 for a soil depth of 0 - 15 cm and 2.82 - 7.74 for a soil depth of 15 - 30 cm) and the organic carbon content varied from 0.13 wt. % to 19.1 wt. % with a median value of 3.67 wt. % in the soil surface layer, with a decrease to a median value of 1.21 wt. %. Total concentrations of the main contaminants Sb and As in the soils from 0 - 15 cm were in the range from 6.2 mg . kg-1 to 142 322 mg . kg-1 with a median of 433 mg . kg-1 and 16 - 2 253 mg . kg-1 with a median of 116 mg . kg-1, respectively, and significantly correlated with each other (R2 = 0.87 at p < 0.000 1). The indication (ID = 65 mg . kg-1 for As and 25 mg . kg-1 for Sb) and intervention (IT = 140 mg . kg-1 for As and 80 mg . kg-1 for Sb) criteria for industrial areas were exceeded in most soil samples and the median concentrations of Sb and As were far higher than their median concentrations within the soils of Slovakia (0.70 mg . kg-1 and 7.20 mg . kg-1 for Sb and As in A-horizon, respectively). Despite the high total concentrations of these metalloids in some soils irrespective of depth, the extractable proportions of Sb and As were low (median of 0.46 % and 0.50 % for Sb and 0.60 % and 0.70 % for As at soil depths of 0 - 15 cm and 15 - 30 cm, respectively). The low mobility of Sb and As has been interpreted as a result of their incorporation into stable secondary mineral phases under oxidizing conditions, in particular Fe-oxy-hydroxides and, in the case of Sb, also due to the formation of separate secondary mineral phases such as romeite (Ca2Sb2O7), cervantite (Sb2O4) and stibiconite [Sb3O6(OH)]. The presence of all these secondary solid phases in the investigated soils was confirmed by optical microscopy, X-ray diffraction and electron micro-probe analyses. Slightly higher mobility of As and Sb in soils from 15 - 30 cm depth than their mobility in soils from the top layer does not exclude the influence of organic matter on the release of these elements into natural waters. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
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