In the present study researchers focused on the isotope composition of oxygen (?18O) in groundwater, which is a natural tracer and provides a better understanding of the water cycle, in terms of origin, dynamics and interaction. The groundwater ?18O at 83 locations over the entire Slovenian territory was studied. Each location was sampled twice during the period 2009–2011. Geostatistical tools (such us ordinary kriging, simple and multiple linear regressions, and artificial neural networks were used and compared to select the best tool. Measured values of ?18O in the groundwater were used as the dependent variable, while the spatial characteristics of the territory (elevation, distance from the sea and average annual precipitation) were used as independent variables. Based on validation data sets, the artificial neural network model proved to be the most suitable method for predicting ?18O in the groundwater, since it produced the smallest deviations from the real/measured values in groundwater.
COBISS.SI-ID: 2705493
The paper presents the use of a simple and cost-effective passive sampling device with integrated active carbon with which to test the possibility of determining the presence of micro-organic compounds (MOs) in underground water and identifying the potential source of pollution as well as the seasonal variability of contamination. The advantage of the passive sampler is to cover a long sampling period by integrating the pollutant concentration over time, and consequently the analytical costs over the monitoring period can be substantially reduced. Passive samplers were installed in 15 boreholes in the Maribor City area in Slovenia, with two sampling campaigns covering a period of about one year. At all sampling sites in the first series, 103 compounds were detected, and 144 in the second series. Of all detected compounds, 53 most frequently detected were selected for further analysis. Passive sampling has proved to be a useful tool for identifying MOs in groundwater and for assessing groundwater quality.
COBISS.SI-ID: 2609493
In the article a geochemical investigation of potentially harmful elements (PHE) in household dust of Idrija is presented. Contents of ten potentially harmful elements (As, Cd, Co, Cr, Cu, Hg, Mo, Ni, Pb, Zn), PHE bearing particles before and after exposure to simulated stomach acid (SSA), Hg binding forms and gastric Hg bioaccessibility were studied. The results showed high Hg contents (6-120 mg/kg) and slightly elevated As content (1-13 mg/kg) with regard to rural and urban background values for Slovenia. Mercury pollution is a result of past mining and oreprocessing activities. Arsenic content is potentiallyassociated with As enrichment in local soils. Four Hg binding forms were identified: Hg bound to the dust matrix, cinnabar, elemental Hg and assumingly Hg oxide. After exposure to SSA, Hg-bearing phases showed no signs of dissolution, while other PHE-bearing phases were significantly morphologically and/or chemically altered. Estimated gastric Hg bioaccessibility was low ((0.006-0.09 %), which is in accordance with identified Hg binding forms and high organic carbon content (15.9-31.5 %) in the dust samples.
COBISS.SI-ID: 2520405
In the article a detailed investigation of soil from populated area of Idrija, which is critically polluted with Hg regarding to legislative values for soil contamination, is presented. The distribution of Hg binding forms, water-soluble Hg fraction and gastric bioaccessible Hg fraction were studied. The results showed that in average about 40 % of Hg distributed between matrix-bound Hg, which is potentially mobile and about 60 % between cinnabar, which is mostly immobile. The concentrations of water-soluble Hg fraction (2.7-178.7 µg/kg) and gastric bioaccessible Hg fraction (0.9-166.1 µg/kg) were interpreted as increased and, as such, important for the local population due to their long-term daily-based exposure. Water-soluble Hg may lead to elevated Hg concentrations in edible plants or groundwater. Gastric bioaccessible Hg may lead to elevated concentrations of Hg in the target vulnerable groups of population (children and gardeners), who often undergo hand-to-mouth exposure during playing activities and gardening.
COBISS.SI-ID: 2520149
A regional geochemical survey was conducted, covering the entire territory of Slovenia. Soil sampling was performed in a 5 x 5 km grid, mercury concentrations were analyzed and a map of mercury spatial distribution was constructed. The determined mercury concentrations revealed an important difference between the western and the eastern parts of the country. A huge anomaly in the western part is the consequence of environmental contamination due to the 500-year history of mining and ore processing in the Idrija mercury mine and partly due to Hg containing rocks on outcrops. Slightly elevated Hg concentrations revealed in the Ljubljana-Kranj and Celje basins indicate urban pollution due to industry, traffic and the use of mercury-containing products. It was established that, besides anthropogenic impacts, lithological and climatic characteristics that determine the type of soil also influence the distribution of mercury in soils. The data were compared to a previously conducted low-density geochemical survey (sampling grid 25 x 25 km) and to the regional geochemical data set (sampling grid 5 x 5 km) supplemented by local high-density sampling data. Comparing high- and low-sample density surveys, it was shown that higher sampling density allows the identification and characterization of anthropogenic influences on a local scale, while low-density sampling reveals general trends in the mercury spatial distribution, but is not appropriate for identifying local contamination in industrial regions and urban areas.
COBISS.SI-ID: 2527829
A new transboundary Upper Pannonian thermal groundwater (GW)body was identified which extends in Austria, Hungary, Slovakia, Slovenia and Croatia. The numerical simulation of freshwater and geothermal aquifers in the Pannonian sedimentary basin and weathered basement rocks provided new insights into the regional and crossborder groundwater (GW) flows and the water balance. The study intended to simulate changes in regional flow patterns and revealed that the current production rates of thermal water dramatically decreased the cross-border flows and caused drawdowns that penetrate far into the neighbouring countries. Although the current regional exploitation cannot be called unsustainable, the quantity status of some geothermal aquifers is deteriorating locally and demands fast management actions. Slovenian researchers have investigated regional thermal water flow in NE Slovenia for a decade and have the best time-series of status of geothermal aquifers in the region. We developed this regional model to assess the transboundary effects on GW levels along with our measurements and interpretations.
COBISS.SI-ID: 2491989
In the article geochemical investigation of urban sediments of Idrija, which were sampled in gully pots of the drainage system (road sediments) and natural streams in the urban area (stream sediments), is presented. The results showed very high contents of Hg (up to 610 mg/kg) in stream sediments, which were interpreted as a consequence of past Hg mining and ore processing activities. The spatial distribution of contents showed that the drainage of bedrocks containing Hg ore, areas of former ore roasting sites, ore residue dumps and contaminated soil impacts on higher Hg concentrations in stream sediments. The contents in road sediments are somewhat lower (up to 120 mg/kg), but it is obvious that identified Hg sources also have an influence on road sediment contamination, however to a lesser extent. With the use of thermo-desorption analysis of Hg binding forms (TDAHg) the occurrence of elemental Hg, Hg bound to the unknown matrixcomponents and cinnabar was determined. An interesting new discovery according to previous research of different materials from Idrija area by TDA-Hg is, that elemental Hg was determined in almost all investigated sediments (n=29) in minor amounts.
COBISS.SI-ID: 2207573
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 mercury in soil samples from the studied areas range from 16 to exceptionally high value of ~18,200 µg/kg, representing 0.0002 to 1.12 % of total Hg in these samples, while in SOM samples leachable mercury concentrations range between 13.3 and 6,000 µg/kg, which corresponds to 0.0017–0.074 % of total Hg determined in SOM. The soluble mercury content in investigated soil profiles ranges from 183 to 18,400 µg/kg (0.038–1.71 % of total Hg). The values from both roasting sites are very low in comparison with the total mercury content. In all cases the soluble mercury in soil solution is ( 2 % with respect to the total concentration of this metal. On average, more than 90 % of soluble Hg occurs in a non-reactive complex bound form, suggesting the preferentially binding of Hg to humic matter. Soluble mercury concentration 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 10 kg of soluble Hg stored in soils of the investigated roasting sites, which is continuously leached to surface waters and deeper into the soil. Because of the predominantly karstic area, considerable amounts of mercury can be transported to aquifers thus posing potential environmental risk.
COBISS.SI-ID: 2258261
According to climate change projections the Alps will be one of the most affected regions in Europe. A basis for adaptation measures to climate changes is the quantification of the impact. This study investigates the impact of projected climate change on the hydrological cycle in the Upper Soča River basin. It is based on the use of climate model data (IPCC A1B emission scenario) as input for hydrological modelling. The simulated impact was quantified by comparing results of the hydrological modelling for the control period (1971–2000) and different scenario periods (2011–2040, 2041–2070, 2071–2100). More distinctive changes are evident in the temporal pattern of mean monthly values which result in warmer and wetter winters and hotter and drier summers in the scenario periods. Changes in precipitation patterns have a major influence on the projected hydrological cycle and are the most important source of uncertainty. Estimated extreme flows indicated increased hazards related to floods, especially in the near future scenario period, while in the far future scenario period distinctive drought conditions are projected.
COBISS.SI-ID: 1936469
During the water concession granting process for the use of thermal water in NE Slovenia various problems were identified, and therefore we suggested elaboration of uniform concession granting principles. We systematically inspected 23 geothermal wells through use of an adapted methodology. In the paper we proposed the use of six key indicators: an operational monitoring, a national surveillance monitoring, best available technology, high energetic and balneological efficiency, and evaluation of recharge and reinjection conditions. Limited or full water concessions could be granted based on their fulfilment. This continuous step-by-step approach is compatible with the EU Water Framework Directive. The approach has been upgraded by 2019 and has become a measure to grant additional thermal water quantities to existing concessionaires in Slovenia.
COBISS.SI-ID: 1905237