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Iskalni niz: "ključne besede" (elements) .

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Biomonitoring and assessment of toxic element contamination in floodplain sediments and soils using fluorescein diacetate (FDA) enzymatic activity measurements: evaluation of possibilities and limitations through the case study of the Drava River floodplain
Péter Szabó, Gyozo Jordan, Tamás Kocsis, Katalin Posta, Levente Kardos, Robert Šajn, Jasminka Alijagić, 2022, izvirni znanstveni članek

Povzetek: The EU Water Framework Directive requires the monitoring and evaluation of surface water sediment quality based on the assessment of risk posed by contamination on the biotic receptors. Floodplain sediments are important receptors of potentially toxic element (PTE) contamination from the upstream catchment areas, and floodplains host climate-sensitive riverine ecosystems and fertile agricultural areas at the same time. This study investigates the effect of PTE contamination on microbial communities in floodplain sediments and soils using the fast, inexpensive and reliable fluorescein diacetate (FDA) method in order to estimate its applicability for sediment quality monitoring and preliminary toxicity-based risk assessment. Sediment and soil samples were collected from the actively flooded alluvial plain and the river terrace areas along a 130-km stretch of the large Drava River floodplain known to be widely contaminated by historical mining, smelting and the associated industry in the upstream Alpine region. Results of detailed data analysis show that the total microbial activity represented by the measured FDA values is related to PTE (As, Cu, Zn, Cd, Pb) concentrations, but this relationship shows significant heterogeneity and depends on the spatial location and on the soil properties such as organic matter content, dissolved salt and nutrient content, and it is specific to the toxic elements. Results show that some microbe species appear to be able to adapt to the elevated PTE concentrations in toxic soil micro-environments, over time. Despite the observed heterogeneity of microbial activity, the results revealed a breakpoint in the FDA dataset around the FDA = 3 FC (fluorescein concentration) value suggesting that microbial activity is controlled by thresholds.
Ključne besede: potentially toxic elements, fluorescein diacetate activity, heavy metals, contamination, biological activity
Objavljeno v DiRROS: 25.08.2022; Ogledov: 662; Prenosov: 202
.pdf Celotno besedilo (6,23 MB)

13.
Rare earth elements and yttrium in cold mineral and thermal (~30-60 °C) waters from Tertiary aquifers in the Mura Basin, north-eastern Slovenia: a review
Polona Kralj, 2022, pregledni znanstveni članek

Povzetek: Cold mineral and thermal waters from Tertiary aquifers in the Mura Basin mainly belong to the Ca-(Mg)-(Na)-HCO3 and Na-HCO3 hydrogeochemical facies, respectively, and the concentrations of yttrium (Y) and lanthanides or rare earth elements (REEs) are far below (10-2 – 10-4) the abundances in the aquifer sediments. Mineral waters are high pCO2, and the plots of concentrations of YREEs normalised to Post Archean Australian Shale (PAAS) show fractionation of Y and heavy REEs (HREEs) over light REEs (LREEs), and a significant positive europium (Eu) anomaly. Thermal water from regionally developed aquifer Thermal I (recently also termed the Mura/Ujfalu Formation aquifer) shows a similar PAAS-normalised pattern with an obvious positive Eu anomaly and the tendency of enrichment with middle REEs (MREEs). The plots of PAAS-normalised YREE concentrations in thermal waters from the underlying low-permeability aquifers with poorly developed fracture porosity and abundant CO2 are flat with insignificant positive Eu anomaly. The abundance and fractionation of YREEs in mineral and thermal waters seems to be mainly controlled by the presence of carbonate complexing ligands, permeability of the aquifers and the related time of water-rock interaction.
Ključne besede: rare earth elements, Yttrium, mineral waters, thermal waters, well cycling, Mura Basin
Objavljeno v DiRROS: 27.07.2022; Ogledov: 650; Prenosov: 200
.pdf Celotno besedilo (2,15 MB)

14.
Impact of urbanization and steel mill emissions on elemental composition of street dust and corresponding particle characterization
Klemen Teran, Gorazd Žibret, Mattia Fanetti, 2022, izvirni znanstveni članek

Povzetek: Street Dust (SD) acts as a sink and source of atmospheric particles containing Potentially Toxic Elements (PTEs) and can pose a possible pathway of PTEs to human bodies. Comprehensive SD study, where 249 samples were collected from rural, urban and industrialized areas aimed to increase the understanding between sedimentation of atmospheric dust derived from anthropogenic activities and elemental composition of SD. Elemental composition for 53 elements (ICP-MS, aqua regia digestion) was determined on fraction <0.063 mm. Significantly increased levels of Sn-Cu-Sb-Bi-Ag-Ba-Mo-Pt-Pb and other elements have been detected in urban environments, compared to the rural ones. SEM/EDS investigation identified that main carriers of Ba, Cu and Sn are most likely particles derived from non-exhaust traffic emissions. Areas around steel mills show a strong enrichment with Cr, Mo, Ni and W, which exponentially decreases with the increased distance from the plant, reaching corresponding urban background 15 and 20 km from the source. SEM/EDS inspection identified spherical and melted irregular particles as the main carriers of the above-mentioned elements. City managers shall adapt measures to reduce amount of vehicular traffic and quantity of deposited SD on the public surfaces and encourage green city planning, while industrial emitters are encouraged to reduce their dust emissions.
Ključne besede: ironwork, pollution, potentially toxic elements, Slovenia, traffic
Objavljeno v DiRROS: 10.06.2022; Ogledov: 608; Prenosov: 294
.pdf Celotno besedilo (10,32 MB)

15.
Towards a holistic approach to the geochemistry of solid inorganicparticles in the urban environment
Martin Gaberšek, Mateja Gosar, 2021, izvirni znanstveni članek

Povzetek: Airborne particulate matter (PM) has a major impact on the biogeochemical cycles of chemical elements in theurban environment. Anthropogenic-derived PM emissions are the cause of some of the most severe environmen-tal and health problems. The presented study aims to improve our knowledge of PM dynamics by introducing amulti-media, multi-analytical and multi-elemental holistic approach to geochemical studies of inorganic PM inthe urban environment. The importance of the holistic approach is highlighted and its application in a casestudy of Maribor (Slovenia) is presented. The chemical composition and individual particulate characteristicsof street, attic and household dust were determined and compared with the characteristics of airborne PM,and PM deposited in snow, together with the chemical composition of the soil. We found that the mineralogicaland chemical composition and the individual solid particle characteristics of the studied media differ consider-ably. Nevertheless, minerals of geogenic origin are present in all media. The highest levels of potentially toxic el-ements (PTEs) in all media, except household dust, are typical for industrial areas. Street dust primarily reflectsthe influence of winter road maintenance and industrial activities, while characteristics of household dust arepredominantly influenced by indoor activities and properties of dwellings. The comparison of the chemical com-position of attic and street dust indicates that emissions of As, Cd, Pb, S and Zn were higher in the past. The char-acterisation of airborne PM and PM deposited in snow is essential for the identification of the mostrecentsourcesof PTE-bearing particles. Several industrial sources and the fate of some particle types in the environment havebeen determined based on thefindings of the SEM/EDS analyses. This study confirms that various environmentalmedia are carriers of diverse geochemical information and highlights the importance of a holistic approach ingeochemistry of PM in urban areas.
Ključne besede: Street dust, attic dust, household dust, airborne particulate matter, potentially toxic elements, SEM/EDS
Objavljeno v DiRROS: 06.01.2021; Ogledov: 1712; Prenosov: 841
.pdf Celotno besedilo (2,91 MB)

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