Mercury (Hg) solubility and reactivity in soils at two extremely contaminated ancient small scale cinnabar roasting sites in the surroundings of the Hg mining area of Idrija (Slovenia) were ...determined in order to assess the mobility of Hg in the aqueous phase and to evaluate the extent of leaching of Hg into Idrijca River and further downstream. Water leaching experiments were performed on soil and SOM (soil organic matter) samples from historical roasting sites Pšenk and Frbejžene trate. The determined concentrations of leachable Hg in soil samples from the studied areas range from 16 to exceptionally high concentration of 18,000μg/kg, representing 0.0002 to 1.1% of total Hg in these samples, while in SOM samples leachable Hg concentrations range between 13.3 and 6000μg/kg, which corresponds to 0.0017–0.074% of total Hg determined in SOM. The soluble Hg concentrations in investigated soil profiles range from 183 to 18,000μg/kg (0.038–1.7% of total Hg). On the average, more than 90% of soluble Hg occurs in a non-reactive complex bound form, suggesting the preferential binding of Hg to humic matter. Soluble Hg in studied soil profiles generally increases with depth. The obtained results show that Hg is effectively transported to deeper soil layers, mainly as soluble organic complexes. It is estimated that there is still about 10kg of soluble Hg stored in soils of the investigated roasting sites, which is continuously leached to surface waters and deeper into the soil.
•Water leaching experiments were performed on soil and SOM samples.•Total soluble, complex-bound and reactive Hg was defined.•Extremely high concentrations (up to 18,000μg/kg) of soluble Hg were determined.•More than 90% of soluble Hg occurs in a non-reactive complex bound form.•We estimate that soluble Hg stored in soils is mobilized to the groundwater.
The soil at ancient roasting sites in the surroundings of the Idrija mine (Slovenia) is highly contaminated with mercury. To assess the impact of mercury on groundwater by infiltration and find an ...eco-friendly remediation method, the leaching of mercury from the soil containing 1347 mg Hg/kg, followed by sorption of the total leached mercury on cost-effective natural zeolite (NZ) clinoptilolite, was performed. The leaching of soil in ultrapure water of pHo = 3.00–11.46 after 24 h resulted in the total leached mercury concentration in the range 0.33–17.43 µg/L. Much higher concentrations (136.9–488.0 µg/L) were determined after the first few hours of leaching and were high above the maximum permissible level in water for human consumption. The NZ showed very good sorption of the total leached mercury, with a maximum removal efficiency of 94.2%. The leaching of mercury in presence of the NZ resulted in a significant decrease of the total leached mercury (1.9–20.3 µg/L compared to 12.8–42.2 µg/L), with removal efficiencies up to 90.5%, indicating immobilization of mercury species. The NZ has a great potential for economically viable remediation of mercury-contaminated environment. However, efforts should be made in the further study of mercury leachability to reduce the mercury concentration in water to acceptable levels.
In his book titled Iz nevidne strani neba: Razkrite skrivnosti staroverstva (From the Invisible Side of the Sky: Secrets of an Old Faith Revealed, Ljubljana 2015), Pavel Medvešček published ...testimonies of an old faith once practiced by some of the inhabitants living in certain parts of western Slovenia. His principal informants were unmarried men, the so-called "uncles". Based on fragments of their narratives, the author of this article explores their lifestyle and their position within their families. Based on the comparative material from Istria and Nadiške Doline/Valli del Natisone, she examines their situation in the wider historical and social context, setting out some particular issues for further research.
The aim of this paper was to test the new sampling media—earthworm casts in a highly contaminated area. The investigation was carried out at the ancient Hg ore roasting site Pšenk in the surroundings ...of Idrija, where extremely high Hg contents in soils and SOM were determined in previous investigations. 32 earthworm cast samples were collected in the research grid 30×30m in order to compare the Hg contents and spatial distribution in earthworm casts to the values and distributions in SOM and soil (0–15cm). Extremely elevated Hg concentrations were determined in earthworm casts from the studied area ranging from 5.4 to 4330mg/kg with the median of 31mg/kg. The Hg values in casts are somewhat lower than in soil (6.3–8600mg/kg) and slightly higher compared to soil organic matter (SOM) (1.5–4200mg/kg). Strong correlation (r²=0.75) between Hg contents in casts and soil was found, while correlation between casts and SOM was positive but weaker (r²=0.35). Spatial distribution of Hg in earthworm casts show the highest concentrations in the central part of investigated area, similar to the distribution in soil. Hg contents rapidly decrease from the center toward the margins of the studied area, where they reach values of less than 50mg/kg. It was shown that Hg contents and dispersion in casts are comparable to those in soil, which indicates that at investigated area soil contamination is strongly reflected in contamination of earthworm casts.
► We compare Hg contents in soil, SOM and earthworm casts. ► The determined Hg contents are in the order of soil>earthworm casts>SOM. ► There is strong correlation between Hg contents in casts and soil. ► Soil contamination is strongly reflected in contamination of earthworm casts.
Results are presented of the first airborne LiDAR survey ever flown in Europe for the purpose of mapping the surface expression of earthquake‐prone faults. Detailed topographic images derived from ...LiDAR data of the Idrija and Ravne strike‐slip faults in NW Slovenia reveal geomorphological and structural features that shed light on the overall architecture and kinematic history of both fault systems. The 1998 MW = 5.6, and 2004 MW = 5.2 Ravne Fault earthquakes and the historically devastating 1511 M = 6.8 Idrija earthquake indicate that both systems pose a serious seismic hazard in the region. Because both fault systems occur within forested terrain, a tree removal algorithm was applied to the data; the resulting images reveal surface scarps and tectonic landforms in unprecedented detail. Importantly, two sites were discovered to be potentially suitable for fault trenching and palaeo‐seismological analysis. This study highlights the potential contribution of LiDAR surveying in both low‐relief valley terrain and high‐relief mountainous terrain to a regional seismic hazard assessment programme. Geoscientists working in other tectonically active regions of the world where earthquake‐prone faults are obscured by forest cover would also benefit from LiDAR maps that have been processed to remove the canopy return and reveal the forest floor topography.
Mercury distribution and partitioning was studied in the River Idrijca system, draining the area of the former Idrija mercury mine, Slovenia. Mercury dynamics were assessed by speciation analysis of ...mercury in water and river bed sediment samples during a 2-year study at locations on the River Idrijca and its major tributaries. Simultaneously, the influence of some major physico-chemical parameters that influence the fate of mercury in the aquatic environment was investigated. The distribution of mercury species in the River Idrijca catchment indicated contamination from mine tailings distributed in the town of Idrija and erosion of contaminated soils. The partitioning between dissolved and particulate mercury phases in river water was found to be mostly controlled by the variable content of suspended solids resulting from changing hydrological conditions and complexation with various ligands present in river water, among which dissolved organic carbon (DOC) seems to be the most important. Overall results indicate that mercury is transported downstream from the mining area mainly as finely suspended material including colloids rather than in the dissolved phase. This riverine transport occurs mostly during short, but extreme hydro-meteorological conditions when remobilization of mercury from the river bed sediments occurs. A significant part of the mercury particulate phase in water corresponds to cinnabar particles. During its transport, important Hg transformation mechanisms that increase the risk of mercury uptake by biota take place, evidenced by the increase in the relative contribution of reactive mercury (Hg R ), dissolved gaseous mercury (DGM) and monomethylmercury (MeHg) downstream from the Idrija mine. However, our data revealed relatively low methylation efficiency in this contaminated river system. We attribute this to the site specific physico-chemical conditions responsible for making inorganic mercury unavailable and limiting the capacity of methylating bacteria.
This study is a continuation of our previous study (Bavec et al., 2015), where the geochemical baseline levels of potentially harmful elements (As, Cd, Co, Cr, Cu, Hg, Mo, Ni, Pb and Zn) in Idrija ...top- and subsoil (0-10 cm and 10-20 cm) at 45 locations were reported. Here we summarise our previous work and present baseline levels of additional 33 elements (Ag, Al, Ba, Be, Bi, Ca, Ce, Cs, Fe, Ga, Hf, In, K, La, Li, Mg, Mn, Nb, P, Rb, S, Sb, Sc, Se, Sn, Sr, Th, Ti, Tl, U, V, Y and Zr) in order to round off the fist systematic geochemical survey of soil in Idrija town and establish a data set of soil elements, which will serve as a baseline for monitoring future changes in the soil chemical composition of the studied area. The baseline levels were determined after aqua regia digestion, their statistical distribution was examined and the medians were compared to the recently established European grazing land and Maribor urban soil medians. To investigate relationships between elements, a correlation-matrix-based hierarchical clustering method was performed and the spatial distribution of their highest levels was examined. The results showed that in general, the median levels of elements in Idrija soil are mostly similar or slightly higher than in European and Maribor soil, with exception of Hg. Elements Al, Bi, Ca, Ce, Co, Cr, Cs, Fe, Ga, Hf, La, Li, Mg, Mn, Nb, Ni, Rb, S, Sc, Th, Ti, Tl, V, Y and Zr are enriched in the rural surroundings, while elements Ag, Ba, Cu, Hg, P, Pb, Se, Sb, Sn and Zn are enriched only partly in the rural surroundings, but mostly in the urban part of the study area. It is assumed that elements, which are enriched only in the rural surroundings, are of natural origin, while elements, which are enriched also in the urban area, are to a certain extent inflenced by anthropogenic activities.
The article focuses on the victims of the Partisan movement in the northern part of the Primorska region during the Second World War. The areas in question are what is today known as the ...municipalities of Bovec, Cerkno, Idrija, Kobarid, and Tolmin. Based on archival sources, it was found that such violence claimed 338 lives in this area. The data is still inconclusive.
The atmospheric distribution and deposition of Hg in the area of the former Idrija Hg-mine, Slovenia, were investigated. Mapping of air Hg
0 concentrations was performed to assess the spatial ...distribution and major sources of mercury to the atmosphere in the area. In addition, analyses of mercury speciation in the air over Idrija were performed during a 4-day sampling campaign in September 2006 to better understand the fate and transformation of Hg in the atmosphere of this specific mercury polluted site. The speciation results were then compared to the results of mercury speciation in the wet and throughfall deposition sampled on a precipitation event basis from October 2006 to September 2007. The Hg
0 concentration in air was mostly below 10
ng
m
−3, with the highest concentration in the area of the former smelter complex exceeding 5000
ng
m
−3. Mercury-bearing airborne particles (TPM) seem to dominate the atmospheric Hg deposition, which revealed noticeable variations between precipitation events (11–76
ng
m
−2
day
−1), mostly as a function of the amount of precipitation. Hg in precipitation was largely (∼50%) associated with the particulate phase (THg
P). No correlation was found between the THg
P and the dissolved phases (THg
D), suggesting that particulate phase Hg is mostly the result of dry deposition. In the throughfall, significantly higher (2–10 fold) Hg concentrations than in associated event precipitation were observed, mostly due to Hg in the particulate phase (∼70% THg). As shown by SEM/EDXS microscopy, an important amount of mercury in the precipitation and throughfall samples is due to the presence of cinnabar particles as a result of the aeolian erosion of cinnabar-containing surfaces in the area.
► Soils surrounding the smelting plant are the main source of Hg in the Idrija region. ► Atmospheric Hg in the Idrija Hg-mine region is subjected to long range transport. ► Mercury-bearing airborne particles dominate the atmospheric deposition.
Purpose
Concentrations and transformations of mercury were measured in river, estuarine, and marine sediments to determine factors affecting the fate of mercury entering the northern Adriatic Sea.
...Materials and methods
Radiotracer methodology was used to compare rates of mercury methylation (
203
Hg), MeHg demethylation (
14
C), and sulfate reduction (
35
S) in sediment depth profiles to concentrations of total and dissolved mercury species in the lower freshwater region of the Isonzo River, the coastal lagoons, and in the Gulf of Trieste, northern Adriatic Sea.
Results and discussion
Mercury was readily methylated and demethylated in all sediments, but the relative activity of these processes varied greatly with location. Methylation activity increased greatly from freshwater to the marine regions; however, demethylation was extremely high in the estuarine and lagoon sites. Ratios of methylation to demethylation were low in these coastal sites but increased further offshore in the gulf, which agreed with increased ratios of MeHg to total Hg (%MeHg) in gulf sediments. Comparisons of microbial activities indicated that sulfate reduction strongly controlled both methylation and demethylation. However, Hg methylation in coastal lagoon sediments was controlled by rapid demethylation and the bioavailability of Hg that was affected by Hg adsorption and precipitation. Methylation in offshore marine sites correlated with sulfate reduction but not the partitioning of Hg between pore water and solid phases. The decrease in sulfide production offshore exacerbated Hg methylation.
Conclusions
The freshwater to marine gradient in the Idrija/Soča/Isonzo/Adriatic region is dynamic, exhibiting horizontally variable rates of microbial activities and Hg transformations that create “hot spots” of MeHg accumulation that are controlled differently in each region.
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