This study evaluates the influence of digestion methods on metal concentrations and results of isotopic analysis of dusts generated during electronic waste processing. E-waste dusts were collected from processing units such as photovoltaic panels, LCD and CRT monitors, and mixed e-waste. Following methods were used for digestion: i) aqua regia with a temperature pretreatment at 110 degrees C, ii) concentrated acids (HClO4, HF, HNO3) with a temperature pretreatment at 550 degrees C. Results showed that concentrated acids with 550 degrees C pretreatment generally yielded significantly higher recoveries for most elements (e.g., Ag, Al, Ba, K, Na, Pb). Conversely, aqua regia was more efficient for Sn recovery, as the higher temperature used with concentrated acids led to the formation of volatile SnCl4 and subsequent Sn loss. A significant Pb isotopic shift was observed between the two methods in glass-rich samples, indicating that aqua regia leached readily available Pb, while concentrated acids (mostly HF) released Pb (of different origin) incorporated within the glass. The isotopic analyses revealed consistent S66/64Zn (-0.078 to 0.052) and S65/63Cu values (0.170 to 0.313) across both methods. Slight changes in S66/64Zn and S114/ 110Cd values were attributed to sample heterogeneity, origin or phase changes after higher temperature treatment at 550 degrees C. A distinct Cu isotopic signature (S65/63Cu 0.067 and 0.078) in CRT dust suggests a different historical origin of Cu in older devices. These findings highlight the crucial role of selecting a digestion method that is appropriate for the specific e-waste dust, to ensure accurate elemental and isotopic analysis.

Estimates of atmospheric inputs of reactive nitrogen (Nr) into ecosystems are often based on vertical deposition. We investigated to what extent horizontal deposition affects total atmospheric deposition of Nr in two sparsely populated mountain regions near the Czech-German-Polish borders in an era of easing pollution. Among three scenarios of horizontal-water contribution to rainfall (additional 5, 10 and 20%), the 10% scenario was considered the most realistic. Between 2023 and 2025, wet horizontal deposition of NH4+-N plus NO3--N constituted as much as 66-77% of total wet inorganic Nr deposition. Because condensation of rain and fog droplets occurs at different altitudes, we hypothesized that the Nr-source mix in horizontal and vertical deposition would differ. N-isotope analyses and Bayesian modeling indicated larger dominance (up to 75%) of vehicle-exhaust derived NH4+-N in fog than in rain. In contrast, the mix of NO3--N sources for fog and rain was nearly identical, with average contributions of six sources making up 9-24% each. Remote large NOx sources originating in coal-burning powerplants and natural-gas burning industries played similarly weak roles as more local and/or diffuse sources related to residential coal and wood burning, traffic and biogenic/soil emissions.

Erosion rates derived from in situ-produced cosmogenic nuclides (CN) have made a significant contribution to quantitative geomorphology. In Europe, extensive CN-based erosion rate datasets mainly cover the Alps and western Europe. However, there is hardly any data from Central and Eastern Europe. This pilot study employs the analysis of in-situ produced cosmogenic 10Be and 26Al to reveal the erosion rate of alluvial sediments of the Jizera River, in the northern part of the Bohemian Massif. Samples of recently deposited alluvial quartz-rich sands were collected from two sites located on the upper and middle river drainage and CN concentrations were analyzed using the multi-isotope accelerated mass spectrometry (AMS) facility newly operating at the Nuclear Physics Institute in & Rcaron;e & zcaron;. Multi-grain size analysis was applied to identify complex sedimentary histories of the sediment. The calculated erosion rates 42 to 52 m Myr-1 are generally consistent between nuclides and align well with similar 10Be-derived erosion rates of 22 to 51 m Myr-1, which have been recently established for the southern part of the Bohemian massif by Robl et al. (2025). At one locality studied, the multi-nuclide technique revealed the coexistence and mixing of non-buried and buried sediments within the alluvial deposits. As an independent check of the erosion rate measurements, the cosmogenic dataset of Jizera River sediments was supplemented with the estimates of the uplift rate of respective bedrocks (45 to 100 m Myr-1), based on available apatite fission-track analysis data. Taking together, these data reveal the general predominance of uplift over erosion over the region, which is a widespread pattern characteristic of the Neotectonic period of accelerated uplift in compressional tectonic zones. Our case study demonstrates the potential of a paired CN technique as a modern tool for quantitative geomorphologic analyses applicable to various other terrains in Central and Eastern Europe.

Findings of coesite and diamond in quartzo-feldspathic rocks confirmed that continental crust, despite its buoyancy, can be subducted to ultra-high pressure (UHP) conditions. In addition to these index minerals, UHP conditions can be revealed by specific minor elements incorporated in common minerals, as it is well known from the Earth's mantle but poorly explored in continental crust. Here, we investigate garnet with coesite inclusions from subducted metagranites of the Eger Crystalline Complex, Bohemian Massif (Czech Republic). The garnet shows chemically distinct concentric domains with minor amounts of P, Na, and Li. From the correlation of these elements, we infer (Na,Li)1P1M2+−1Si−1 substitution, where Li compensates for the Na deficiency in a 2∶3 ratio. This is the first time that such coupled substitution in garnet has been defined and clearly connected to UHP conditions in natural samples, proving itself as a new tool indicative of UHP conditions. Moreover, garnet in subducting slabs needs to be considered as an important Li carrier, capable of transporting significant amounts of Li into the Earth’s mantle.

In many countries worldwide, NOx emissions currently decrease as a result of pollution control, while NH3 emissions stagnate or continue to increase. Little is known about horizontal deposition of NO3− and NH4+, the oxidation/neutralization products of these primary pollutants. To close the knowledge gap, we studied atmospheric inputs of NO3− and NH4+ at two mountain-top sites near the Czech–German–Polish borders during winter. Horizontal deposition via ice accretions (rime) made up 26–30 % of total atmospheric input of reactive nitrogen (Nr). Such high horizontal depositions should not be neglected in ecosystem N studies which currently often consider only vertical deposition via snow. Snow nitrate N was the largest type of Nr deposition (40–52 %), with snow ammonium N being the second largest (20–30 %). Rime ammonium N contributed a similar amount to total Nr input as rime nitrate N (12–16 %). The total inorganic Nr deposition was 4–6 kg ha−1 winter−1. Across the sites, the mean δ15NNH4+ and δ15NNO3− values fell in a relatively narrow range from −3.1 to −7.3 ‰. Three systematic isotope patterns were observed: (i) NH4+-N was always heavier in rime than in snow, (ii) NO3−-N was always heavier in rime than in snow, and (iii) NO3−-N was always heavier than NH4+-N. For source apportionment, the Bayesian isotope mixing model SIMMR was used. Counter-intuitively, vehicles were larger sources of NH3 in rime than volatilation from animal waste plus fertilizers (46 vs. 19 %). The largest NO3− contributions to rime were derived from vehicles and biomass burning, followed by natural gas combustion and coal burning in power plants and households. Natural gas represented the largest source of nitrate in snow. Nitrate sources appeared to be better-mixed than ammonium sources. Our isotope-based source apportionment differed from national emission inventories, offering original insights into local atmospheric Nr inputs.

The selection of decomposition method and processing of samples are crucial for precise analytical measurements. We selected three waste samples originating from different industrial activities and one raw material (ewaste dust, fly ash, slag, coal). Especially e-waste dust is a unique material with very distinctive composition that requires a specific approach in terms of sample preparation and decomposition. Samples were thermally treated at 110, 550, 1050 degrees C and subsequently decomposed using different methods: i) aqua regia, ii) concentrated acids (HNO3, HClO4, HF), iii) alkaline fusion. Temperature treatment at 1050 degrees C resulted in the formation of difficultto-decompose phases in samples with high organic matter content (e-waste dust, coal) associated with incomplete decomposition by aqua regia and changes in isotopic composition (e-waste dust: Delta 114/110Cd1050-110 degrees C = -0.110, Delta 65/63Cu1050-110 degrees C = -0.776, Delta 66/64Zn1050-110 degrees C = -0.089; coal: Delta 114/110Cd1050-110 degrees C = 0.672, Delta 65/ 63Cu1050-110 degrees C = 0.558, Delta 66/64Zn1050-110 degrees C = -0.110). Another effect observed after temperature treatment at 1050 degrees C was the analytical loss caused by the thermal decomposition of volatile components present in the fly ash. The analytical loss (up to 98.5 % Cd, 98.7 % Cu, 99.7 % Pb, 57.4 % Zn) was linked with significant Cd and Zn isotopic changes (Delta 114/110Cd1050-110 degrees C up to 0.873, Delta 66/64Zn1050-110 degrees C up to 0.238). The changes in Cu isotopic composition in fly ash caused by thermal decomposition were also recorded after processing at 550 degrees C (Delta 65/ 63Cu550-110 degrees C was 0.154). The results clearly show that the origin of the sample and different decomposition methods, together with temperature pretreatment, have a significant effect on results of concentration and isotopic measurements.

Knowledge of relative importance of Pb sources is a prerequisite of developing strategies that would decrease atmospheric pollution by this highly toxic metal. In the industrial city of Ostrava (Czech Republic, Central Europe), we identified nine major Pb pollution sources and isotopically studied air-borne Pb at five sites along a SW-NE transect. Site 3 in the central city, situated close to a Fe-metallurgical operation, was characterized by six times higher winter-time Pb content in PM10, compared to less industrial sites 1, 2, 4 and 5. The Bayesian model MixSIAR estimated decreasing contributions of sources to air-borne Pb in the order: unleaded fuel plus tire wear > Mississippi-Valley type ores > Variscan ores > stone coal > soft coal > Fe-ore > brake wear > legacy leaded gasoline. Individual contributions decreased from ∼29 % to ∼5 %. Winter-time coal incineration in households and thermal power plants resulted in a seasonality in Pb emission rates. We infer that the model may underestimate the role of stone coal burning, possibly due to its time-dependent 206Pb/207Pb and 208Pb/207Pb isotope signatures. Also, the isotope signatures of Pb released into the air during coke production and its consumption during the Fe metallurgy process may have varied over time. Reducing coal incineration in households using obsolete boilers becomes a priority among measures to improve air quality in the Ostrava conurbation.

This study presents an integrated hydrological-hydrochemical approach to quantify reactive nitrogen (N-R) cycling in temperate mountain catchments. It employs stable isotope analyses (delta H-2, delta O-18 in water, delta N-15 in NH4+, and NO3- and delta O-18 in NO3-) to resolve interactions between water flow and N transformations. A two-component runoff model reveals groundwater as the dominant discharge contribution (75%-90%), with 10%-25% derived from rapidly infiltrating soil water-highlighting a swift hydrological response to precipitation. In addition, this work quantifies all N mineralization in vadose zone and denitrification in groundwater and their seasonal variation within a well-studied network of N-saturated temperate forests (i.e., the Czech GEOMON Network). Our results show that increased precipitation infiltration diminishes microbial N production and N-2 losses, but maximizes catchment N-R exports. Direct input of atmospheric N-R to runoff was recorded during a short period of spring snow melting only. Denitrification calculated from N-15 fractionation of NO3- in soil and groundwater accounts for 15%-24% of total mineralized N (N loss is 0.6-1.6 kg N ha(-1) year(-1)), with precipitation shifts markedly influencing N-R outflows. This framework enhances predictions of climate change impacts on nutrient transport and water quality in mountain catchments, which are critical water sources for ecosystems and human use. Overall, application of this approach can offer key insights for mitigating ecological risks from increased N-R mobilization, especially under rising atmospheric N deposition and global warming effects.

We describe scheelite in five types of mineral deposit from the Bohemian Massif (greisen, orogenic Au, reduced intrusion-re-lated gold systems (RIRGS), oxidized and reduced skarn) via cathodoluminescence (CL) imaging and laser ablation induc-tively coupled plasma mass spectrometry (LA-ICP-MS) analyses. We document variability in the scheelite composition within single grains and/or deposit types that reflects the nature and evolution of the ore-forming fluids. We provide scheelite typical trace element characteristics and chondrite-normalized REE patterns for different deposit types, confirming that scheelite can be used as an indicator mineral for their exploration. For example, scheelite from greisen-related deposits usually rich in Sn, Sr, Y and HREE with various ranges of median values in individual deposits (0.05-8.0 ppm, 232.4-567.1 ppm, 0.06-465.0 ppm and 0.06-632.5 ppm, respectively) and with typical chondrite-normalized REE patterns showing Eu negative or positive anomaly. Under UV light scheelite from Sn-W deposits displays variable colours from whit ish via yellowish to bluish. In contrast to greisen-related deposits, scheelite from Au-orogenic association is usually relative rich in Pb (median range in individual deposits: 6.1-11.2 ppm), and relatively poor in Mg, Mo and Nb. Flat and bell-type chondrite-normalized REE patterns show a pronounced Eu positive anomaly. Under UV light it is predominantly homoge-nous and bluish. Scheelite from oxidized skarn is enriched in Mo, Nb and ELREE (median range in individual deposits: 311.4-7214.1 ppm, 1.3-214.9 ppm, and 1.1-1375.8 ppm, respectively), and scheelite from reduced skarns is characterized by the lowest median ranges of Nb (1.7-107.8 ppm), Y (0.69-41.1 ppm), Mn (0.5-17.0 ppm) and Zn (0.04-0.252 ppm) in in dividual deposits, when compared to all the groups studied. Scheelite from oxidized and reduced skarn deposits displays several types of chondrite-normalized pattern: (1) LREE-enriched with a positive or negative Eu anomaly, (2) Bell-shaped REE patterns with negative orwithout Eu anomaly, and (3) Flat REE patterns with a negative Eu anomaly. Scheelite from oxi-dized and reduced skarn deposits is commonly zoned and mostly bluish under UV light.

Quantification of geogenic inputs of magnesium (Mg) and calcium (Ca) as essential nutrients, and strontium (Sr) as a Ca proxy, into biomass and catchment runoff is indispensable for studies of forest sustainability in an era of persisting acidification and climatic change. Supergene processes control the isotope composition of base cations released from bedrock into solution. Isotope signatures of dissolved Mg2+, Ca2+ and Sr2+ are complementary to the isotope composition of weathered rock because both are derived from the same parent material. We investigated shifts in S26Mg, S44Ca, and 87Sr/86Sr isotope ratios from fresh bedrock toward the weathering front in six common crystalline lithologies, including leucocratic granite, quartz diorite, melasyenite, melagranite, augen gneiss and amphibolite. About 20 cm below the deepest soil horizon, the isotopic composition of Mg, Ca and Sr in weathered rock differed significantly from that of fresh rock in nine out of 18 cases. Bulk-rock S26Mg and S44Ca values were less sensitive to partial dissolution of minerals than 87Sr/86Sr ratios. Statistically significant shifts in 87Sr/86Sr were observed in all six lithologies. Weathered rock had higher 87Sr/86Sr ratios than fresh rock in three cases, and lower 87Sr/86Sr ratios in another three cases. The site-specific 87Sr/86Sr shift was explained by contrasting weathering rates of Rb-rich and Rb-poor minerals in most rocks. Both lower S26Mg and higher S44Ca values of weathered amphibolite were likely related to isotope fractionations accompanying in-situ formation of secondary smectite. Continuing mineral dissolution in overlaying soils may cause additional Mg, Ca and Sr isotope effects.

Changes in organic matter accumulation in wetlands are critical for climate dynamics. Different nitrogen (N) inputs in Sphagnum-dominated peat bogs can lead to varying rates of carbon (C) and N accumulation, influencing greenhouse gas emissions. We investigated how contrasting N deposition shapes microbial communities in two Czech peat bogs, focusing on biological N2 fixation (BNF) as a key N input in pristine wetlands. Higher N deposition resulted in a more active microbial community with increased enzyme activity and C acquisition, potentially accelerating decomposition and reducing C storage. Enhanced denitrification, indicated by active nosZ Clade I genes, suggests that higher N inputs may increase N losses through denitrification. In contrast, the lower N site showed a less active microbial community with slower decomposition, beneficial for C sequestration, though potentially less adaptable to future N increases. Experimental BNF rates were 70 times higher at the high N site, consistent with elevated diazotroph activity indicated by active nifH gene. Phosphorus (P) availability and NH4+/NO3− ratios appeared to drive BNF differences, emphasizing the need for managed N inputs to maintain peatland ecological functions.

Microbial N2-fixation helps to sustain carbon accumulation in pristine peatlands and to remove CO2 from the atmosphere. Recent work has provided evidence that this energetically costly process is not completely downregulated at sites with higher availability of reactive nitrogen (Nr). We studied nitrogen (N) cycling at three high-elevation, mainly rain-fed, Sphagnum-dominated peat bogs in the northern Czech Republic receiving medium to high amounts of reactive nitrogen (Nr) via atmospheric deposition. 15N/14N isotope ratios were determined in Nr deposition, along vertical peat profiles, and in a laboratory incubation study using fresh Sphagnum and 15N-enriched atmospheric N2. Our objective was to assess the potential for biological N2-fixation at the selected study sites in light of various biogeochemical parameters. Historically, all the peat bogs experienced similar changes in atmospheric Nr (mainly NO3--N and NH4-N) inputs. Nr depositions at all three sites peaked between 1980 and 1990. During that time period, the highest annual depositions were close to 10 kg ha-1 yr-1 at the slightly more polluted site Uhlirska (UHL) than at Male mechove jezirko (MMJ) and Brumiste (BRU). Since ca. 1990, atmospheric deposition of Nr has been steadily decreasing. Living Sphagnum had variable N concentrations with similar means for all three sites (1.1, 1.0 and 0.9 wt. % at MMJ, BRU and UHL, respectively). Downcore, peat density remained nearly constant at MMJ but increased at BRU and UHL. Ash contents were below 10 wt. % at least to the depth of 20 cm. With an increasing peat depth, both N concentration and δ15N values generally increased, while C/N ratios tended to decrease. At depths > 10 cm, N/P ratio was lower at UHL than at the other two sites and remained nearly constant downcore. N/P ratio at MMJ increased from ~10 to ~20 with an increasing depth, whereas the N/P ratio exhibited a zigzag vertical pattern at BRU, reaching a value of 40 in deeper segments. The potential for biological N2-fixation was investigated using a replicated laboratory incubation of fresh Sphagnum in a closed system following an application of 98 % enriched atmospheric N2. The experiment lasted for 7 days. The control Sphagnum samples had δ15N values of -4.0 ‰ (BRU and UHL) and -3.7 ‰ (MMJ). At the end of the incubation, the δ15N significantly increased only in MMJ moss reaching + 70 ‰, while it remained unchanged in BRU and UHL moss. Biological N2 fixation was thus recorded at only at MMJ, a site with the lowest N/P ratio in the topmost 2-cm thick sections. Potential N2 fixation rates at MMJ were similar to values previously reported for Finland (Leppänen et al. 2015) but ~7 times lower than at sites located in Patagonia, Chile (Knorr et al. 2016). References Leppänen et al., 2015. Plant and Soil, 389, 185-196. Knorr et al., 2016, Global Change Biology 21, 2357–2365.

The general configuration of the main continental blocks in the Gondwana supercontinent and the Ediacaran-early Paleozoic tectonic evolution of its northern margin are widely accepted. However, reconstruction of the original positions and the question of potential separation of the Gondwana -derived crustal segments that are now included in the Variscan and Alpine orogenic belts remain controversial. The Western Carpathians, part of the Alpine-Carpathian belt, represents an important crustal segment broken -off from northern Gondwana and later incorporated into both the Variscan and Alpine collisional orogens. The earliest tectonic evolution and paleogeography of the pre-Variscan basement of the Western Carpathians remains poorly known, due to insufficient age data and intense polyphase tectonometamorphic overprints, both Variscan and Alpine. This paper provides new results of U-Pb dating and Hf isotopic analysis of detrital zircons as well as a whole -rock geochemical study from metavolcanic-sedimentary basement units of the Western Carpathians. The obtained age spectra suggest that the sedimentary succession was supplied dominantly by Ediacaran (c. 600 Ma) zircons, with a relatively minor role for Stenian-Tonian (c. 1.2-0.9 Ga) and Paleoproterozoic cratonic (c. 2.2-1.8 Ga) zircons. The mixed Hf isotopic signature (epsilon Hf(t) values ranging from -20 to +12) of the Ediacaran zircons indicates substantial mixing of mantle -derived magmas with mature crustal material, typical of continental magmatic arcs. In contrast, the mostly negative epsilon Hf(t) values (-15 to +4) of the cratonic zircons suggest recycling of an older continental crust. The presumably youngest part of the sequence is also characterised by high proportion of early Paleozoic zircons with generally negative epsilon Hf(t) values (-10 to -2). The zircon U-Pb age spectra, Hf isotopic patterns and whole -rock geochemical signatures of the studied Western Carpathians sequences are interpreted as reflecting deposition at a progressively developing Cambrian-Silurian passive margin setting. The West Carpathian data have been correlated with a comprehensive detrital zircon U-Pb age and Hf isotope data set compiled from possible source areas and other Gondwana -derived units to test the possibility of their primary linkages. These correlations indicate strong similarity in both zircon U-Pb age spectra and Hf isotopic compositions to other parts of the Ediacaran (Cadomian) continental magmatic arc. Older, cratonic sources are linked to the Saharan or East African parts of northern Gondwana, whereas the early Paleozoic detritus must represent a local volcanic source. Taken together, our new data from the Western Carpathians provide constraints for a new paleogeographic model of the northern African part of the Gondwana passive margin.

Topazolite (greisen) is a rock formed essential by quartz and topaz, with accessory white mica, tourmaline, sulphides (molybdenite and arsenopyrite), wolframite and cassiterite. This rock was found in the Krkonoše and Jizera Mountains in the western Sudetes. In Poland, this metasomatic rock occurs at the contact between leucogranite and mica schist (associated with hydrothermal kaolinization) in a narrow zone between the settlements of Rebiszow and Gierałtówek. On Czech territory, similar topaz quartzolite (greisen rock), consisting of up to 65 % quartz and 32 % topaz, was found near the settlements of Růžek and Vítkov near Chrastava in association with orthogneiss. The high content of topaz in this rock offers the possibility of using it as an abrasive in high-speed abrasive water jet technology for cutting and surface treatment of hard metallic and non-metallic materials. In the crushed form, after being concentrated in a treatment plant, topaz could be a natural abrasive with a wide range of applications. However, the results of technological testing of the physical and mineralogical characteristics of the topaz concentrate indicate its unfavorable properties caused by the high fissility of topaz. This leads to losses of topaz during its technological adjustment to the required grain size or during recycling. It has been shown that abrasive concentrates with topaz content above 90 % are promising, especially for special applications of abrasive water jet technology. Mastering the technology for processing of the source raw material, i.e. topaz quartzolite, into a topaz-rich concentrate, and subsequent applied research on the use of topaz abrasives in industry are crucial.

Rocks with an enrichment of topaz (quartz-topaz quartzolites) found in the Krkonoše-Jizera crystalline complex in northern Bohemia or a potential secondary raw material from the mining of cast mica from greisen (Czechia) can be a suitable raw material for obtaining topaz concentrate for its subsequent use in Abrasive Water Jet (AWJ) technology as an abrasive. Topaz from these rocks has good mineralogical parameters, density and hardness. The grains of the topaz concentrate are also less fractured. This article outlines the basic properties of topaz in relation to its use as a potential abrasive for AWJ, including basic testing of its cutting abilities compared to other abrasive concentrates. The cutting performance of topaz was found to achieve 90.5

A Central European catchment underlain by base-poor orthogneiss was studied using mass budgets and Mg–Ca–Sr isotope systematics. For 50 years, the catchment received large amounts of partly soluble dust from a nearby cluster of coal-burning power plants, while suffering from acid rain and severe spruce die-back. Our objective was to investigate to what extent anthropogenic dust contributes to Mg and Ca in runoff and to identify fractionations affecting Mg and Ca isotope composition of 13 ecosystem pools and fluxes. We hypothesized that if Mg and Ca runoff fluxes were significantly larger than their atmospheric inputs, Mg and Ca isotope ratios in runoff would converge to those of bedrock Mg and Ca. This relationship could be obscured by isotope fractionations. Strontium characterized by negligible isotope fractionations served as a Ca proxy. There was a strong positive correlation between Mg and Ca fluxes via spruce throughfall and catchment runoff. Monitoring of rainfall, canopy throughfall and runoff fluxes revealed a 20-, 15- and 15-fold excess of Mg, Ca and Sr in runoff, respectively, compared to atmospheric deposition fluxes. This sizeable excess per se would indicate predominance of geogenic base cations in runoff. The behavior of Mg and Ca isotopes was de-coupled. Petrographic study indicated that 92