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Povzetek: Herein, we present a dataset of the geochemical and isotopic characteristics of water collected from September 2012 to June 2014 to evaluate biogeochemical processes within the Oplotnica River silicate catchments. Additionally, we collected soil samples at Javorski creek to characterize the soil profiles using stable isotopes of carbon and nitrogen. Discharge and temperature data for the Oplotnica River at the Perovec gauging station were gathered from the Slovenian environment agency. Temperature at both Javorski and Lukanjski creeks was measured on-site, while pH and conductivity were measured in the lab with Metrohm pH low ionic strength glass electrode and Pt1000 electroconductivity electrode, connected to Metrohm 712 Conductometer. Cations (Na+, K+, Ca2+, Mg2+, Mn2+, NH4+) were analyzed with Metrohm Metrosep C4-150/4.0 column without suppression and anions (NO3-, NO32-, SO42-, Cl-, PO43-) with Metrohm Metrosep A Supp 5-150/4.0 column with chemical suppression. Both connected in Metrohm Ion Chromatography modular system. Total alkalinity was measured with double-end point titration (pH=4.5, 4.2) measuring pH with Metrohm pH low ionic strength glass electrode and titrating with 0.01 M HCl controlled by Metrohm 702 SM Titrino titrator. Dissolved organic carbon (DOC) was measured with TOC analyser Shimadzu TOC-5000A as a difference between dissolved total carbon (DTC) and dissolved inorganic carbon (DIC). Thermodynamic modeling was performed with the PHREEQC speciation program to evaluate pCO2 and the saturation state of calcite and dolomite. The major solute composition of the analyzed surface water was as follows: Na+Ca2+Mg2+K+ and HCO3-SO42-Cl-NO3-. In surface water the δ13CDIC ranged from -26.1‰ to -1.4‰, and the 13CPOC from -28.2 to -22.3‰, and 15N from -2.2 to 2.6‰ (measured only in September 2012). 13Corg. ranged from -28.3 to -24.9‰, while 15N ranged from -4.9 to 5.4‰ at three soil profiles (up to a depth of 70 cm) at Tratice I, II and III locations at Javorski creek. Characteristic plants within catchment area have 13C in the range from -31.2 to -29.2‰ and 15N in the range from -8.0 to -5.5‰. Data were collected through field and laboratory analyses. These data were used to calculate saturation indices, partial pressure of CO2 (SIcalcite, SIdolomite, pCO2), and to perform a mass balance calculation of carbon to determine the processes that contribute most to the isotopic composition of dissolved inorganic carbon (δ13CDIC). Furthermore, bicarbonate weathering intensity was calculated within the catchment area. The main conclusions are that the saturation index of calcite (SIcalcite) ranges from -6.1 to -1.9, and the saturation index of dolomite (SIdolomite) ranges from -12.7 to -4.2. The bicarbonate weathering intensity is 10.4 mmol/km²·s, which is typical for silicate catchments.
Ključne besede: isotope Geochemistry, biogeochemistry
Objavljeno v DiRROS: 21.01.2026; Ogledov: 214; Prenosov: 100
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Povzetek: Poznavanje prostorske porazdelitve vsebnosti kemičnih elementov v tleh je bistveno za zagotavljanje varnega in zdravega bivalnega okolja ter pomembno za prostorsko načrtovanje, posege v prostor in spremljanje dolgoročnih antropogenih vplivov na okolje. Zaradi velikega števila prebivalcev je to še posebej pomembno v urbanih okoljih. V monografiji podajamo rezultate raziskav vsebnosti kemičnih elementov, pH vrednosti in vsebnosti celotnega ter organskega ogljika v tleh v Mariboru in prikaze njihovih prostorskih porazdelitev z geokemičnimi kartami. Vzorčili smo zgornjih 10 cm tal po celotnem Mariboru v mreži 500 × 500 m. Po razklopu z zlatotopko smo z ICP-MS analizirali vsebnosti 65 elementov. Rezultati kažejo, da tla na območju Maribora niso močno obremenjena s potencialno strupenimi elementi, odkrili smo le manjša območja in nekatere izolirane lokacije z visokimi vsebnostmi bakra (Cu), svinca (Pb) in cinka (Zn), predvsem znotraj industrijskih območij ter starega mestnega jedra. Njihove mediane, ki so nekoliko nad slovenskimi, velika variabilnost v vsebnostih in prostorska porazdelitev kažejo na vsaj deloma antropogen izvor. Deloma antropogen izvor lahko pripišemo tudi kadmiju (Cd), antimonu (Sb), kositru (Sn), živemu srebru (Hg) in srebru (Ag). Nekateri preostali elementi, kot so aluminij (Al), kobalt (Co), krom (Cr), železo (Fe) in vanadij (V) jasno odražajo prevladujoč vpliv geološke podlage. S predstavljeno raziskavo smo želeli opredeliti trenutno geokemično stanje tal v Mariboru, približati rezultate splošni javnosti in omogočiti dolgoročno spremljanje stanja tal ter okolja na splošno.
Ključne besede: soil, chemical elements, potentially toxic elements, geochemical mapping, urban geochemistry
Objavljeno v DiRROS: 28.08.2025; Ogledov: 616; Prenosov: 1988
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Povzetek: It was once believed that only microbes and viruses inhabited the subseafloor crust beneath hydrothermal vents. Yet, on the seafloor, animals like the giant tubeworm Riftia pachyptila thrive. Their larvae are thought to disperse in the water column, despite never being observed there. We hypothesized that these larvae travel through the subseafloor via vent fluids. In our exploration, lifting lobate lava shelves revealed adult tubeworms and other vent animals in subseafloor cavities. The discovery of vent endemic animals below the visible seafloor shows that the seafloor and subseafloor faunal communities are connected. The presence of adult tubeworms suggests larval dispersal through the recharge zone of the hydrothermal circulation system. Given that many of these animals are host to dense bacterial communities that oxidize reduced chemicals and fix carbon, the extension of animal habitats into the subseafloor has implications for local and regional geochemical flux measurements. These findings underscore the need for protecting vents, as the extent of these habitats has yet to be fully ascertained.
Ključne besede: subseafloor, hydrothermal vents, tubeworms, larvae, vent fluids, bacterial communities, geochemical flux, geochemistry, marine biology
Objavljeno v DiRROS: 22.10.2024; Ogledov: 878; Prenosov: 1420
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Povzetek: The potential environmental impact of historical mining and ore processing on stream sediments and water was studied in a small siderite iron ore deposit with diverse sulfide mineral paragenesis. The main aim was to characterize solid carriers of potentially toxic elements (PTEs) in stream sediments and mine waste, to understand their fate in fluvial systems. General mineralogy (X-ray powder diffraction) and individual solid PTE carriers (scanning electron microscopy/energy dispersive spectroscopy) were correlated with the geochemical composition of stream sediments, mine waste, and stream waters (inductively coupled plasma mass spectrometry). Primary solid PTE carriers were pyrite, chalcopyrite, sphalerite, Hg-bearing sphalerite, galena, and siderite. Slightly alkaline and oxidizing conditions in stream water promoted the transformation of primary phases into secondary PTE carriers. Fe(Mn)-oxide/oxyhydroxides were major sinks for Pb, Zn, and As. Compared to background levels, Co (14.6 ± 2.1 mg/kg), Cu (30 ± 2.9 mg/kg), Ni (32.1 ± 2.9 mg/kg), Pb (64.5 ± 16.4 mg/kg), Zn (175.3 ± 22.5 mg/kg), As (81.1 ± 63.7 mg/kg), and Hg (2 ± 0.8 mg/kg) were elevated in mining area. Mine waste contained similar PTE carriers as stream sediments, but much higher PTE contents. Prevailingly low PTE concentrations in streams, with the exception of As (1.97 ± 2.4 µg/L) and Zn (4.5 ± 5.7 µg/L), indicate the stability of PTE carriers. Environmental effects were not significant, and additional monitoring is recommended.
Ključne besede: environmental mineralogy, environmental geochemistry, potentially toxic elements, stream sediments, solid phases, iron ore deposit, SEM/EDS
Objavljeno v DiRROS: 16.11.2022; Ogledov: 1693; Prenosov: 660
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Povzetek: A comprehensive study of attic dust in an urban area is presented. Its entire life cycle, from determining historical emission sources to recognising the processes that take place in attic dust and its potential to impact human health is discussed. Its chemical composition and morphological characteristics of individual solid particles reflect past anthropogenic activities. High levels of Be-Cd-Cu-Sb-Sn-Pb-Te-Zn and occurrence of Cu-Zn shavings are typical for an industrial zone characterised by a foundry and a battery factory. High levels of Co-Fe-Mo-Ni-W-Ba-Cr-Mg-Mn-Nb-Ti and occurrence of various solid Fe-oxides, particularly spherical particles, were identified in another industrial zone, which was dominated by the automotive and metal-processing industries. Emissions from coal combustion affected the distribution of S-Se-Hg-Tl-As-Ag-U. The predominant mineral in attic dust is gypsum, which was presumably formed in situ by the reaction of carbonate dust particles and atmospheric SO2 gas. The high oral bioaccessibility of As-Cd-Cu-Pb-Zn in the gastric phase and high bioaccessibility of As-Cu-Cd-Ni in the gastrointestinal phase were identified. Determined characteristics of attic dust and identified possibilities of prolonged human exposure to it indicate that attic dust should be treated as an excellent proxy for historical air contamination as well as a potentially hazardous material for human health.
Ključne besede: multi-element composition, scanning electron microscopy, oral bioaccessibility, unified BARGE method, urban geochemistry
Objavljeno v DiRROS: 23.06.2022; Ogledov: 1887; Prenosov: 654
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