This study investigates fossil seagrass accumulations in the Pliocene-Pleistocene Kritika Formation on Rhodes Island using geochemical, organic petrology and palaeobiological proxies. The studied section can be correlated with the lower Calabrian (1.7-1.6 Ma). Inorganic geochemistry revealed fluctuations between freshwater and marine environments, suggesting a dynamic estuarine environment, as supported by the analysed delta C-13(org) values, which varied from -25.0 to -23.5 parts per thousand. High concentrations of terrestrial organic matter indicate significant riverine input to the coastal area under warm and humid climatic conditions. Further, elevated Ni (720-1100 ppm) and Co (41-60 ppm) concentrations in the sediments indicate a basic/ultrabasic (ophiolitic) sediment source in the catchment area. The absence of marine organisms in these accumulations and reduced estuarine salinity suggest that Posidonia leaves were transported within the estuary rather than deposited in situ. Organic geochemical analyses revealed minor peaks of submerged plant-specific n-alkanes (C-21, C-23, C-25) similar to modern dead Posidonia accumulations. Abundant short even n-alkanes (C-16, C-18) associated with heterotrophic bacteria and fungi are also present, indicating microbial decomposition. Identical geochemical signatures in samples without Posidonia body fossils confirmed the presence of amorphous organic matter of seagrass origin, further demonstrating that organic geochemical proxies can identify ancient seagrass meadows even in the absence of body fossils.

In formerly glaciated mountain regions, lacustrine sediments effectively trace landscape responses to postglacial changes. However, the sedimentary archives preserved in lakes on the southern side of the Tatra Mountains have received little attention to date, and the environmental signals they contain are poorly understood. Here, we provide a detailed characterisation of lacustrine sedimentary facies from eight lakes in the Vysoké Tatry Mountains. Multi-proxy analyses coupled with radiocarbon dating reveal lake-specific responses to environmental and climatic changes during the Late Glacial–Early Holocene, highlighting the influence of local topography and lake morphology on facies evolution. In general, the basal recovered sediments in the studied lakes are represented by minerogenic facies. The oldest minerogenic facies is commonly represented by finely and regularly laminated clay and silt, interpreted as varves and likely deposited until an estimated ~13.7–13.3 kyr BP, corresponding to the late Bølling–Allerød Interstadial. The termination of this sedimentary pattern and its transition into more homogeneous or irregularly laminated mud suggest a change in meltwater dynamics, possibly reflecting reduced stable annual meltwater contributions from persistent cryospheric sources, likely including debris-covered relict glaciers and/or rock glaciers. Gyttja represents another dominant facies overlying the minerogenic deposits. Its heterochronous onset across studied lakes, estimated to range from ~12.2 to ~8.4 kyr BP, appears to have been modulated by the termination of the Younger Dryas marginal glaciation and the volume of siliciclastic input.

Microbiological investigations of skin, hair, and intra-corporeal tissue of the mummified body of Zsofia SeredyAndrassy, who had been laid to rest in a glass coffin in the Krasna Horka Castle in southeastern Slovakia, revealed necrobiome dominated by the phylum Firmicutes followed by representatives of the phyla Actinobacteria and Proteobacteria. Optically visible bright-to-yellow mineral precipitates on the skin and organs are dominated by potassium sulphate (the mineral arcanite), with a minor admixture of chlorides (probably halite). Only a very rare calcium carbonate has been identified on the hair surface. The high concentrations of potassium in both tissue and hair, together with the 34S-rich isotope compositions of keratin sulphur (delta 34S = 11.6-11.7%o CDT) and skin leachate (delta 34S = 7.1-8.5%o CDT), suggest either the excessive use of K2SO4 during medical treatment or intentional embalming - the first such documented case in Europe for the period. Biogenic microbial or fungal origin of essentially pure K2SO4 is highly unlikely. The high residual levels of non-excreted salts, combined with the dry microclimatic environment of church crypt, resulted in the body mummification and crystallization of potassium sulphate on the skin surface and internal organs. The commonly accepted conjecture regarding the natural mummification of Zsofia's corpse, which is believed to be caused by calcium hydrogen carbonate or calcium bicarbonate-rich drip water and subsequent desiccation, should be rejected.

A cryogenic mineral assemblage was investigated in a cave that experienced widespread glaciation in Late Pleistocene. Barite and opal crystallized alongside calcite during the progressive water freezing in cave chambers within thawing permafrost. Barite inclusions evolved from prismatic nuclei into complex spherulitic aggregates, occasionally shaped by now-vanished constraints on growth, presumably imposed by ice, CO2, and possibly CO2 clathrate. Clathrate formation at 0 degrees C requires pressures above 10 bar, a condition that can be met in freezing water pools through pressure buildup from volumetric expansion. Dispersed nanoparticulate silica is identified as a disordered opal variety. Stable strontium isotope ratios proved useful in constraining the provenance of the parental water and confirm its autochthonous seepage origin within the limestone massif. Geochemical modelling indicates early oversaturation and precipitation of barite and silica, often preceding calcite, suggesting that microscopic cryogenic minerals may persist even where macroscopic calcite is absent. These findings deepen our understanding of sub-zero mineral precipitation with potential implications for other terrestrial and extraterrestrial cryogenic environments.

Mesozoic high-latitude forests developed within polar circles are poorly known, as are the ecosystems that formed within them. Cockroaches and praying mantises from palaeo-polar deposits in Victoria: Koonwarra (Australia, southern hemisphere), Yakutia, Taimyr, Khabarovsk, Magadan, and Chukotka (Russia, northern hemisphere) occur within taphonomically diverse sedimentary, 'coal' and amber deposits. Along with high-latitude deposits in Alaska, Canada, New Zealand, southeastern Australia and Antarctica, these assemblages were affected by light polarities. The polar assemblages considered here include both nocturnal and diurnal insects with unusual features such as dark coloration, specific wing shapes, metallic cuticle, and two main reflective and three additional simple eyes. Many taxa show relictual characteristics, although hypermodern lineages occurred. By combining paleobiology, sedimentology/physics and organic petrography/chemistry, our research suggests that high-latitude Cretaceous organisms in the northern hemisphere exploited tropical microclimates with permanent summer insolation, whereas southern polar hothouse forests were more temperate. We name this unusual assemblage lacking colorful cockroaches the 'Dark Biota', which developed during Earth's global warming maximum (up to 24.3 degrees C) in the Barremian-Aptian. We interpret it as inhabiting multi-level forests comprised of canopy conifers and small-leaf angiosperms strongly influenced by megafires. Deciduous forests likely originated in these regions in response to the unusual light conditions. Press Release: An analysis of fossil cockroaches suggests tall, tree-dominated forests were growing close to Earth's two poles during the Cretaceous, possibly with tall trees directly at Earth axis. In the northern hemisphere, this fauna is interpreted as representing the first strictly seasonal deciduous "rainforest", charac-terized by alternating photosynthetic polar days and hibernating polar nights.

In this work, we evaluated the biological and geological contributions to the formation and preservation of the oxidation zones in & Lcaron;ubietov & aacute;-Podlipa, & Lcaron;ubietov & aacute;-Sv & auml;todu & scaron;n & aacute;, Poniky-Farbi & scaron;te and & Scaron;pania Dolina-Piesky. This case study highlights the importance of the biological contribution to weathering processes of ore deposits. It may be extended to other similar sites in order to assess the magnitude of biological input. Using U-Pb dating, secondary minerals from Podlipa were dated to 22 +/- 6 and 19 +/- 4 Ma (Lower Miocene). At this time, this region experienced deep weathering under a humid and warm climate and tectonic quiescence. The isotopic (O, H) composition of the secondary minerals shows that they formed from Lower Miocene meteoric water under surface temperatures. The delta C-13(PDB) values in malachite (-19 to -17 parts per thousand) document a biological source of C, from soil CO2. The delta O-18(VSMOW) values of the PO4 groups in the accessory fluorapatite in the host rocks (1.8 +/- 1.7 parts per thousand, 1 sigma) and pseudomalachite in the oxidation zone (12.1 +/- 2.9 parts per thousand, 1 sigma) show substantial biological P input into the oxidation zone. A biogenic source of both C and P agrees well with the palaeoclimatic constraints based on the radiometric dating. The oxidation zones at Podlipa, Sv & auml;todu & scaron;n & aacute; and Farbi & scaron;te are contemporaneous with kaolin crusts in the same area; they were all preserved only where they were covered by young (14-12 Ma) volcanic rocks and exposed recently by erosion. The other oxidation zones in the Tatric and Veporic units, if they existed, were destroyed by the Pliocene uplift of these units. The oxidation zone at Piesky is younger, dated to 2.5 Ma (Early Pleistocene) when the global temperatures in interglacials were similar to the present, decreasing in glacials by similar to 4 degrees C. The different climate at this time is manifested by scattered delta C-13 values, reflecting surface temperature and vegetation fluctuations at this time.

Cremation became the dominant funerary practice in the Middle Danube Region during the Roman Period (RP) (1st-4th century) and reappeared in the Early Medieval Ages (EMA) (6th/7th-8th century). This study aims to reconstruct differences in cremation conditions from the Gbely-Kojat & iacute;n site (Slovakia, RP and EMA) and the P & rcaron;& iacute;tluky site (Czech Republic, EMA) through FTIR-ATR (IRSF, C/C, OH/P, and BPI) and carbon and oxygen isotope (delta 13C and delta 18O) analyses of cremated remains. The findings suggest that Gbely-Kojat & iacute;n (RP) exhibited higher levels of heat intensity and more controlled practices, whereas P & rcaron;& iacute;tluky revealed lower levels of heat intensity with greater variability. Gbely-Kojat & iacute;n (EMA) exhibited intermediate values, indicating potential deviations or alternative cremation strategies. Results demonstrate that technological differences in cremation between sites and periods were shaped primarily by ritual and pyre management, rather than environmental factors.

This study focused on testing the response of the assimilation apparatus of evergreen Pinaceae species to increasing levels of oxidative stress simulated in manipulative experiments. Needles were collected from mature individuals of Pinus mugo, Pinus cembra, Pinus sylvestris, Abies alba, and Picea abies at the foothill (FH) and alpine treeline ecotone (ATE) in the High Tatras (Western Carpathians). The injury index (INX), quantified by the modified electrolyte leakage (EL) method, indicated severe needle damage due to exposure to extremely high levels of O3. Ozonation induced changes in the chemical composition of the needles, which were detected via gas chromatography-mass spectrometry. The oxidative stability (OxS) indicator derived from INXs was used to determine the stomatal O3 flux-based critical level CL(OxS), with the threshold value of OxS at -0.05, corresponding to 5

Paleoenvironmental reconstruction was conducted on a short sediment core from a subalpine lake (Low Tatra Mountains, Slovakia) spanning the past 300 years, and aimed to assess the impact of climatic oscillations and the well-documented human activities in the catchment. An analysis of subfossil chironomid remains was applied, supported by a land cover reconstruction using historical maps and orthoimagery. Two main phases of lake development were identified: the first, preceding major anthropogenic pressure and the second, which followed the opening of the first hotel in the lake vicinity in 1950, characterised by massive infrastructure and tourism expansion. The oldest assemblages date to the coldest period of the Little Ice Age (LIA) and were dominated by Derotanypus and Paratanytarsus austriacus-type, indicating very cold and oligotrophic conditions. Warming following the end of LIA caused a gradual shift in the taxonomic composition, with previously dominant taxa disappearing or decreasing in abundance. Dominance of Tanytarsus lugens-type, Zavrelimyia and Heterotrissocladius marcidus-type still reflects relatively cold temperatures and low productivity. Taxonomic composition remained mostly stable until the middle of the twentieth century, when construction work in the catchment caused deforestation, the number of year-round tourists increased, and the lake was dammed to improve conditions for boating and angling. The resulting increased nutrient loading, oxygen depletion and macrophyte development are evident from the rising abundances of taxa tolerant of high trophy. The increase of thermally plastic taxa in the twenty-first century reveals recent climate warming, which will likely only exacerbate the already considerable negative human influence, making lake recovery improbable.

The famous Kremnica and Zlata Bana epithermal deposits are hosted in two different Neogene volcanic fields in the Western Carpathians, Slovakia. In both deposits, stibnite-rich veins occur outside of major vein structures, accompanied by illite, illite/smectite, and kaolinite alteration, and affiliated to late-stage fluids (< 2 wt% NaCl eq., < 150 degrees C). Sulfur isotopic composition of stibnite and sulfides is different at both deposits, likely due to a different magmatic-hydrothermal evolution of the parental magmatic chambers in both Volcanic Fields. The Sb isotopes (delta Sb-123), however, show similar values and trends of gradual simultaneous increase with delta S-34 values, explained by a progressive precipitation of stibnite and its fractionation with the fluid. The data were modeled by two coupled Rayleigh fractionation models, (for Sb and for S), assuming a predominant Sb transport in HSb2S4- with a variable amount of S species. At both deposits, the heaviest delta Sb-123 values are accompanied by a decrease in the delta S-34 values probably due to the commencement of pyrite/marcasite precipitation. According to the models, stibnite precipitation was triggered by temperature decrease accompanied by mixing with a mildly acidic fluid (pH 4-5) of a steam-heated CO2-rich condensate on margins and in the final stages of epithermal systems.

The Rudno nad Hronom-Brehy ore deposit in Slovakia represents an important locality of epithermal precious metal mineralization in the Central Slovak Volcanic Field. The main ore structures in the area are Anna, Goldschram, Filip, Johan de Deo and Priecna veins. In this work, we present mineralogical, paragenetic and geochemical aspects of the ore mineralization, hydrothermal alteration patterns, fluid inclusions, isotopic composition of sulfur (delta S-34) and K-Ar age of ore mineralization. Four mineralization stages were recognized, the third one being split into two substages. (1) Pyrite stage with quartz, K-feldspar, arsenopyrite and pyrite. (2) Base-metal stage with sphalerite, galena, chalcopyrite, Au-Ag alloys and famatinite. (3a) Early Ag stage with tetrahedrite-(Zn), tetrahedrite-(Fe), argentotetrahedrite-(Zn), tetrahedrite-(Cd), argentotetrahedrite-(Cd) and greenockite. (3b) Late Ag stage with pyrargyrite, polybasite, pearceite, cupropolybasite, cupropearceite, acanthite and galena. (4) Late Ag-Cu stage with bornite, stromeyerite, mckinstryite, chalcocite, digenite, covellite and uytenbogaardtite. Veins are rich in silver with an average Ag : Au ratio of 85 : 1; in some parts of the veins, Ag content reaches up to 1950 ppm and Au up to 42.7 ppm. The neutral to alkaline style of hydrothermal alteration is represented by K-feldspar, quartz, carbonates, smectite, interstratified illite/smectite, and chlorite (clinochlore, chamosite). This assemblage indicates a low sulfidation origin of the mineralization formed at 177-224 degrees C. The delta S-34 values from the base-metal stage varies from + 2.8 to + 3.5 parts per thousand for chalcopyrite from the northern part of the Priecna vein, from + 1.9 to + 2.6 parts per thousand for galena, from + 4.9 to + 5.2 parts per thousand CDT for pyrite from the Anna vein. These values indicate a relatively homogeneous sulfur source, most likely related to an igneous or mixed igneous and host-rock source. Fluid inclusions in quartz associated with the base-metal stage have low salinity (1.1-1.6 wt. % NaCl eq.) and homogenization temperatures of 176-250 degrees C. The available data suggest that the base-metal stage was accompanied by cooling and dilution owing to a meteoric fluid. The temperature estimated from the tetrahedrite thermometer of the early Ag stage is similar to 170-205 degrees C. According to the paragenetic relationship and mineral stability, the deposition temperatures in the late Ag stage did not exceed 160 degrees C. The late Ag-Cu stage formed at temperatures of < 93 degrees C. The results of K-Ar radiometric dating from the hydrothermal alteration returned an average age of 12.5 +/- 0.3 Ma. The studied mineralization is possibly related to the initial stage of resurgent horst tectonic activity and rhyolite volcanism of the fifth stage of Stiavnica stratovolcano formation.

The commonly known larimar is usually a gem-quality, bluish pectolite (NaCa2Si3O8OH), intergrown with other associated minerals such as natrolite, prehnite, calcite, chlorite, found only in the Dominican Republic. Less frequently it shows consecutive and/or sequential green, blue, and white coloration within single amygdales/veins developed in altered (chloritized, serpentinized) Cretaceous basalts of the Dumisseau Formation. The origin of larimar is linked to the circulation of low-temperature (<170 °C) alkali-rich deuteric fluids that were later mixed with meteoric waters. Variations of CL colors, ranging from weak brown in green pectolite to strong yellow (Mn2+-activated) in blue and white species, were ascribed to the transition from oxic to suboxic crystallization environment within the single larimar bodies. These changes could be induced by the burial of magmatic rocks and resulted in the emergence of early zeolite (natrolite), and subsequent formation of native copper in a sulphur-deficient hydrothermal environment. Pectolite-forming elements (e.g. Ca and Na), followed by such transition metals as Cu, Cr, Co, and Ni, were released via the alterations of magmatic minerals (diopside, aegirine-augite, and chromite-magnetite) and/or leached from basaltic groundmass. Decoupling between δ18O values of blue (up to 10.67‰), green (up to 9.66‰), and white pectolite (up to 15‰) was maintained by a progressive temperature drop during ongoing pectolitization and/or presence of the boiling-related environment. Meanwhile, anomalously low δD values (from –390.51‰ to –294.02‰) indicate that the crystal structure of pectolite tends to incorporate light hydrogen isotope regardless of the original δD values in mineralizing fluids.

Multiproxy palaeoenvironmental analyses represent a promising tool for complex reconstructions of continentsea or air-sea interactions in shallow marine environments. This is in particular illustrated by the case of strong climatic variations in the late Pleistocene to mid-Holocene. A unique combination of geochemical proxies (Nd-143/Nd-144, Sr-87/Sr-86, delta O-18 and delta C-13 isotope analyses, n-alkane analysis and biomarker study) together with micropalaeontological data (foraminifera, calcareous nannoplankton and diatoms) allowed to precisely characterise two marine floodings (mid-Holocene and late Pleistocene) in the Zanzibar Channel (NW Indian Ocean, Tanzania). The climate of the late Pleistocene interval was arid compared to the Holocene. The fully oligotrophic environment characteristic of the late Pleistocene flooding (similar to 115-130 ka) was episodically interrupted by intervals of intense rainfall with episodes of increased nutrient input during the mid-Holocene (similar to 5-10 ka). The dominance of seaweed meadows in the Holocene and late Pleistocene contrasts with the modern environment dominated by seagrass ecosystems. Relatively non-radiogenic epsilon(Nd) signatures in the Zanzibar Channel during the Holocene and late Pleistocene indicate a strong influence of riverine input draining the Precambrian basement on the African mainland. The main inflow of seawater was from the south, consistent with the flow direction of the East African Coastal Current and the directions of the March to October monsoon winds. A promising tool for future applications as indicators of seagrass/seaweed meadow type ecosystems may be the presence of specific diatom taxa.

The robustness of the Strontium Isotope Stratigraphy (SIS) as a chemostratigraphic tool was tested in the Miocene epicontinental Central Paratethys using new 87Sr/86Sr results obtained for 129 foraminiferal tests and various marine invertebrate shells that were converted to numerical ages using the global 87Sr/86Sr curve for the Phanerozoic open oceans. These ages were compared with those expected from either magnetostratigraphic, radiometric or biostratigraphic studies applied to selected sections from different Central Paratethys basins. The results from different basins showed variations in 87Sr/86Sr values for specific time intervals; therefore, it is not possible to construct a unique 87Sr/86Sr curve for the Central Paratethys region that can be used for chemostratigraphic purposes. The 87Sr/86Sr signal in semi-enclosed basins tends to reflect the lithology of the source areas. For example, marine basins surrounded by areas of Mesozoic carbonate rock cover are associated with a reduced 87Sr/86Sr signal compared to the global 87Sr/86Sr signal primarily due to the drainage of these Mesozoic carbonate rocks and transfer of their specific Sr signal. By contrast, areas affected by continental runoff from crystalline terrains in combination with limited connection to surrounding marine domains were found to show an elevated 87Sr/86Sr signal compared to the global one. Additionally, it was demonstrated that infaunal, eutrophic and hypoxic species (foraminiferal genus Uvigerina and molluscs) show a shift towards a relatively higher 87Sr/86Sr signal. Therefore, our data show that variable 87Sr/86Sr patterns occur in semi-enclosed domains, primarily reflecting local settings and thus hampering reliable SIS ages. In particular, the best SIS results in the studied Paratethys area occur during periods of maximum marine connectivity, when other (biostratigraphic) methods can be applied, and then become unreliable as connectivity diminishes.

ABSTRACT While humic lakes are common in northern Europe, in central Europe they are rare and our understanding of their ontogeny is insufficient. Here, we present the reconstruction of the development of a humic lake in the Tatra Mountains (Slovakia) over the last 8000 years using chironomids along with diatoms, pollen and non‐pollen palynomorphs. The compositional changes in aquatic proxies suggest three developmental stages. Since its formation the lake has been oligotrophic (phase 1), and its chemistry was controlled by subsurface waters rich in base cations buffering the effect of acid humic substances from forest and peat that were already present in the catchment. The beginning of the transition to phase 2 (~4400 cal a bp ) is marked by simultaneous alterations in all proxies. Climate change combined with the local geochemistry was able to alter the limnological conditions supporting unique chironomid assemblages that have no analogues in recent Carpathian lakes. At ~ 3400 cal a bp the lake shifted to a phase when acidophilic/acidotolerant taxa indicate characteristic humic lake conditions (phase 3). Some chironomid taxa appearing ~ 2000 years ago for the first time indicate a dystrophic state in which the lake has remained until now. Human activities have been detected in the area since the Aeneolithic but had no direct influence on the lake.

Stibnite is a relatively common mineral in epithermal deposits, with little known about Sb transport and efficient stibnite precipitation. The famous Kremnica Au-Ag low-sulfidation deposit and Zlatá Baňa intermediate-sulfidation Pb-Zn-Cu-Au-Ag-Sb deposit are hosted in two different Neogene volcanic fields in Western Carpathians, Slovakia. In both deposits, stibnite-rich veins occur outside of major vein structures, accompanied by illite, illite/smectite, and kaolinite alteration, and affiliated to late-stage fluids (< 2 wt

Abstract. The study of freshwater carbonates, such as travertines and speleothems, provides valuable insights into the regional biases of mid-Holocene climate development in Central-Eastern (CE) and South-Eastern (SE) Europe. The formation of a lake in the travertine deposition system of the Santovka site, located at the transition of the Western Carpathians and the Pannonian Basin, has led to the preservation of a valuable record. We analyzed the litho- and microstratigraphy, chemical composition, including δ18O and δ13C stable isotopes, and geochronology of the Santovka-village section. We then compared these palaeoclimatic records with reference records from Central-Eastern and South-Eastern Europe in terms of significant climate shifts. The prevalent part of the section studied, which spans between 8200 and 6400 cal BP, is represented by fluvial/fluvio-lacustrine sediments and lake marl. The 8.2 ka BP event was only detected in the δ13C record from the nearby Santovka-PB section. However, we found an abrupt change in both isotopic records around 7400–7200 cal BP, which is likely connected to increased detrital input and some minor palaeoecological changes in the Santovka-village section. These changes are most likely associated with the drying of the lake. The 8.2 event in Central-Eastern (CE) and South-Eastern (SE) Europe is well reflected in the δ13C records, while the change in δ18O was insignificant. In contrast, the newly suggested climate shift around 7400–7000 ka BP was detected at most sites in both δ18O and δ13C records. This development could be connected to a change in air mass circulation, synchronous with declining solar irradiance and increased evidence of drift ice in the North Atlantic.

Electrolyte leakage (EL) is the method commonly used to test the cell membrane integrity of plants under stress conditions. The cells of the leaf may be damaged by ozone (O3) entering the intercellular space as an oxidative stress agent. The modified EL method was used to test the oxidative stability (OxS) of plant tissue against O3-induced oxidative stress. The modification includes simulation of the artificial oxidative stress by additional ozonation of plant samples in the laboratory chamber. This modified EL method was applied to Pinus mugo Turra needle samples collected in the subalpine zone of the High Tatra Mts (Western Carpathians), in the years 2019 and 2020. Changes in the chemical composition of samples after artificial ozonation were traced by gas chromatography/mass spectrometry (GC/MS) analysis. In addition, O3 uptake through open stomata was estimated by calculation of the modelled ozone dose (MO3D). We also conducted an inspection of visible injury (VIN) on the needle surface focused on the occurrence of O3-induced symptoms and biotic harmful agents. Regarding OxS results as well as VIN indices, P. mugo needles showed relatively low sensitivity to oxidative stress induced by O3. Therefore MO3D in a range between 14 and 16 mmol m−2 can be considered as O3 dose with minor phytotoxic effect on P. mugo growing in the mountains of central-eastern Europe.