Eleven inscriptions, discovered on as yet unpublished fragments of monuments from the territory of Roman Emona, are discussed in this contribution. The monuments, kept in the City Museum of ...Ljubljana, were most probably discovered in the secondary position and date from the 1st to the 3rd century AD
Particulate matter concentrations (PM
10
, PM
2.5
, PM
1
) and microclimatic parameters (air temperature, CO
2
) were monitored in the Škocjan Caves (Slovenia). The effects of tourist visits on ...the PM concentrations and the cave’s microclimate are immediate and direct, but these values normalise relatively quickly. The results showed seasonal, diurnal, and spatial differences in all parameters studied. Due to the higher number of visitors, their influence on the cave’s microclimate and PM
10
and PM
2.5
concentrations is greater in summer than in winter. The measured PM
1
levels depend on the ventilation in the cave, as air transport plays an important role in their introduction into the cave. PM consists of minerals of natural origin resulting from the re-suspension of cave sediments due to strong air currents generated by the opening of the doors to tourists and their walks. The second most common influence is the anthropogenic phases originating from maintenance work in the cave, electronic devices, cave lighting and emissions from outside the cave (aerosols from the polluted Reka River, industry, traffic, gypsum waste disposal). In order to upgrade the sustainable use of the UNESCO-listed Škocjan Caves for tourism, we propose regular monitoring of PM and a detailed characterization of individual PMs and their sources, in addition to monitoring of the cave’s microclimate and biology.
When playing in sandboxes, children are particularly vulnerable to poisoning with potentially toxic elements (PTE) due to their hand-to-mouth behaviour. In Slovenia, the city of Celje is heavily ...contaminated due to zinc ore smelting and iron industry. In some sandboxes, sand from Mežica Pb-Zn mine waste was used. Granulometric and XRF analysis showed that all samples contain larger percentage of fine-sized particles and some have higher As, Ba, Cd, Pb and Zn contents than allowed. By XRD and SEM/EDS analysis we identified carries of PTE, and confirmed three possible sources of contamination: the waste material from the Pb-Zn mine, the emissions from local industry and from the old Zn-smelting stockpile used as a landfill. The total health risk (ΣHI) exceeds critical value in one sandbox. The bioaccessibility of PTEs is alarming due to presence of highly soluble metal-bearing particles. Study revealed importance of combining results of health risk evaluation with bioaccessibility of elements, which is a function of the carriers of PTE. This knowledge is essential for undertaking remedial measures. Improper use of waste material could result in introducing hazardous material in the environment. We propose frequent replacement of sand and stricter legislation regulating status and usage of waste materials.
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•Playground sandboxes and nearby soils are contaminated with PTE.•PTE sources are mine waste used as sand and local Zn-smelter stockpile resuspension.•PTE carriers are Pb-Zn ore minerals, Zn-smelting slag and pigments.•Improper reuse of mine waste material is important contamination source.•health risk indices are low, but high PTE bioaccessibility is of great concern.
The origin of the soils formed on carbonate rocks remains uncertain, as they are probably of polygenetic origin. Of particular interest are the elevated contents of some trace elements detected in ...these soils, as they can hardly be attributed to insoluble residues of carbonate rock. The aim of this study was to uncover the relationship between heavy minerals in bedrock and soil and to identify other sources that influence the mineral and chemical composition of soil. We investigated representative samples of soils and dolomite bedrock as well as sandstones and marlstones from the nearby flysch basin as an expected source of the aeolian contribution. XRD and SEM/EDS showed that mineral diversity is higher in soils compared to the dolomites. Heavy minerals found in dolomite insoluble residue include sphalerite, Ti-oxide (probably rutile), zircon, fluorite, pyrite, minerals of REE phosphates and apatite group, interpreted as terrigenous detrital material. The mineral composition of soil heavy fraction is only partly following insoluble residues of bedrock and indicates possible aeolian contribution. Comparison with nearby flysch sandstones and marlstones showed similarities in mineralogical diversity by the presence of chromite and Fe-Cr(Mn) oxides (probably carmichaelite). Other minerals present in soils and flysch layers, such as Ti-oxide (probably rutile), zircon, REE phosphates, and pyrite grains, however, show similarities in mode of occurrence and transport indications. Signs of aeolian transport on the grains detected in soils were further confirmed by SEM/EDS.
Black deposits covering speleothems, cave walls and floors in Postojna Cave and Predjama Cave (SW Slovenia), and charcoal found in soil outside the Postojna Cave, were studied in order to establish ...their origin and age. SEM/EDS analysis of these deposits from both caves indicated that they are charred plant remains, very similar to oxidised charcoal in soil. Stable carbon isotope δ13C values of −29.41‰ (Črna Jama, P1), −26.9‰ (Predjama), and −25.1‰ (charcoal in soil) confirm their origin from biomass burning. Radiocarbon dating from Postojna Cave (Črna Jama (P1) 8394±35calyrB.P. and Pisani Rov 8235±25calyrB.P.) suggests that the oldest analysed black deposits formed in the Early Holocene (Mesolithic). The age is consistent with soil charcoal found at 1m depth in the surrounding area. Black deposits from Predjama were dated to 4095±25calyrB.P. (Eneolithic) and were caused by burning fires at the cave entrance, as supported by archaeological remains. Prehistoric (2375±20calyrB.P.) charcoal from the upper part of the soil profile (0.5 to 0.6m) and historic (1240±29calyrB.P. or 745calyrCE) black deposits from Postojna Cave (Črna Jama, P2) are related to forest fires, which are most likely human-induced. We interpret the oldest dated black deposits in Postojna Cave as traces of Early Holocene natural forest fires, since fire activity inside Črna Jama and Pisani Rov is not supported by archaeological remains. Favourable cave entrance morphology and microclimate allowed smoke to enter the cave during the winter period and deposit on speleothems. But an anthropogenic cause of forest fires cannot be excluded, since there are well-documented Mesolithic archaeological cave sites located close to the area. The study shows that black deposits on speleothems in caves are an important palaeoenvironmental record and proxy for Holocene climate.
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•Black deposits on speleothems and charcoal in soils in karst area were studied.•SEM/EDS, 14C dating, C stable isotope analysis, organic matter analyses were applied.•Black deposits and charcoal in soil proved forest fires event dating 8200calyrB.P.•Black deposits on cave speleothems are important proxy for Holocene climate.
In the caves, the formation of cave minerals is a consequence of a variety of chemical reactions, some of them also due to human activity. There are many caves in Slovenia, but sulphate minerals are ...not very often reported and analysed. In this study, the presence of sulphate minerals is detected by SEM/EDS analysis of speleothems from Črna Jama, a cave near Kočevje (southern Slovenia). The cave is characterised by its dark, almost black colour on cave walls, floor and speleothems. Anthropogenic influence in the cave is still visible, including the remains of a fireplace, some inscriptions on the walls and wooden containers. The analyses of some of the black-coated speleothems reveal the presence of calcium sulphate, confirmed by XRD as gypsum. Gypsum crystals are around 50 μm in size, and they occur in thin crusts. Additionally, some rare authigenic baryte crystals a few micrometres in size are detected. The sulphates δ
34
S value in gypsum found on dark coloured speleothems is + 10.4‰ Vienna Canyon Diablo Troilite (VCDT), while the sulphate δ
34
S of the bedrock is + 8.6‰ VCDT. The more likely source of sulphate ions is thus biomass burning rather than bedrock. Also, bedrock and biomass ash are a very probable source of calcium and barium. The highly probable pyrogenous origin of sulphates draws attention to human impact on cave mineralogy.
Marbles from the Pohorje area in Slovenia are investigated by mineralogical–petrographical analyses of thin sections as well as by cathodoluminescence in order to detect their local variability in ...texture and mineral assemblages. The CL colours observed in a cold cathode device are related to the manganese contents. An attempt is made to relate the textures seen under CL to mineral reactions during the process of metamorphism. The predominantly calcite marbles from Pohorje exhibit orange luminescence with some dolomite lenses with red luminescence. The typical mineral assemblages are calcite+tremolite+phlogopite or calcite+dolomite+tremolite+phlogopite. Therefore, the estimated temperature from the stability of mineral assemblage is assumed at approximately 500
°C.