Total Elemental Composition Research Articles

The Early Cretaceous Sembar Formation, Southern Indus Basin, Pakistan: Biomarkers and Trace Element Distributions to Investigate the Sedimentary Palaeoenvironment and Organic Matter Input.

The Early Cretaceous clay-rich facies of the Sembar Formation represent the most significantly occurring organic-rich sediments in the Southern Indus Basin of Pakistan. In this study, detailed geochemical research of total organic carbon, biomarker, mineralogy and trace elemental compositions, together with kerogen microscopic analysis, were carried out and used to understand the organic matter input and the dispositional environmental setting of the organic-rich Sembar shale. The Sembar shales have high organic matter, as indicated by the total organic carbon (TOC) content of up to 2.31 wt %. These shales contain a high abundance of liptinites (i.e., alginite and bituminite), with significant reactive vitrinite maceral, reflecting a mixed-organic matter with a high contribution of marine-derived input. The biomarker distributions evidence the finding of mainly marine organic matter. The biomarker characteristics such as Pr/Ph, Pr/n-C17, Ph/n-C18, and tricyclic terpane ratios together with C27-C29 regular sterane distributions show that the source of organic matter was primarily marine-derived from mainly phytoplankton algae, along with amounts of land plant input, and accumulated under a low oxygenated environment. The Sembar shale facies are characterized by high Mo trace element content and high V/Ni and Mo/TOC ratios, suggesting anoxic and nonsulfidic environmental conditions during time deposition. The geochemical proxies such as the Sr/Ba ratio and gammacerane/C30 hopane (G/C30) index suggest that the Sembar shale facies were deposited in a relatively low moderate stratified water column. The higher gallium (Ga) than rubidium (Rb), with high Ga/Rb ratios, indicates a high abundance of the kaolinite mineral, thereby deducing the subaerial weathering during the warm and humid climatic conditions. In this case, these warm and humid climatic conditions cause an influx of masses of nutrients, which could be attributed to increasing marine primary bioproductivity. These large masses of nutrients into the photic zone are also attributed to the presence of the upwelling system during the deposition time. Therefore, such conditions of bioproductivity and preservation of organic matter (OM) resulted in the accumulation of organic carbon in the shale facies of the Early Cretaceous Sembar Formation.

Characteristics and health implications of fine particulate matter near urban road site in Islamabad, Pakistan

The escalating issue of air pollution has become a significant concern in urban regions, including Islamabad, Pakistan, due to the rise in air pollutant emissions driven by economic and industrial expansion. To gain a deeper understanding of air pollution, a study was conducted during winter 2022–2023, assessing physical, chemical, and biological factors in Islamabad. The findings revealed that the average concentration of fine particulate matter (PM2.5) was notably greater than the World Health Organization (WHO) guidelines, reaching 133.39 μg/m³. Additionally, the average concentration of bacteria (308.64 CFU/m³) was notably greater than that of fungi (203.55 CFU/m³) throughout the study. Analytical analyses, including SEM-EDS and FTIR, showed that the PM2.5 in Islamabad is composed of various particles such as soot aggregates, coal fly ash, minerals, bio-particles, and some unidentified particles. EF analysis distinguished PM2.5 sources, enhancing understanding of pollutants origin, whereas Spearman's correlation analysis elucidated constituent interactions, further explaining air quality impact. The results from the Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-OES) indicated a gradual increase in the total elemental composition of PM2.5 from autumn to winter, maintaining high levels throughout the winter season. Furthermore, a significant variation was found in the mass concentration of PM2.5 when comparing samples collected in the morning and evening. The study also identified the presence of semi-volatile organic compounds (SVOCs) in PM2.5 samples, including polycyclic aromatic hydrocarbons (PAHs) and phenolic compounds, with notable variations in their concentrations. Utilizing health risk assessment models developed by the US EPA, we estimated the potential health risks associated with PM2.5 exposure, highlighting the urgency of addressing air quality issues. These findings provide valuable insights into the sources and composition of PM2.5 in Islamabad, contributing to a comprehensive understanding of air quality and its potential environmental and health implications.

Elemental composition of grass phytoliths: Environmental control and effect on dissolution

Plant phytoliths, which represent the main pool of silica (Si) in the form of hydrous Si oxide, are capable of providing valuable information on different aspect of environmental issues including paleo-environmental reconstruction and agricultural sustainability. Phytoliths may have different chemical composition, which, in turn, affects their preservation in soils ad impacts terrestrial cycle of the occluded elements including micro-nutrients and environmental toxicants. Yet, in contrast to sizable work devoted to phytoliths formation, dissolution and physico-chemical properties, the mechanisms that control total (major and trace) elemental composition and the impact that various elements exert on phytolith reactivity and preservation in soils remains poorly known. In order to fil this gap in knowledge, here we combined two different approaches – analytical trace element geochemistry and experimental physical chemistry. First, we assessed full elemental composition of phytoliths from different plants via measuring major and trace elements in 9 samples of grasses collected in northern Eurasia during different seasons, 18 grasses from Siberian regions, and 4 typical Si-concentrating plants (horsetail, larch, elm and tree fern). We further assessed the dissolution rates of phytoliths exhibiting drastically different concentrations of trace metals.In the European grasses, the variations of phytolith chemical composition among species were highly superior to the variations across vegetative season. Compared to European samples, Siberian grass phytoliths were impoverished in Ca and Sr, exhibited similar concentrations of Li, B, Na, Mg, K, V, Zn, Ni, Mo, As, Ba, and U, and were strongly enriched (x 100–1000) in lithogenic elements (trivalent and tetravalent hydrolysates), P, Mn, Fe and divalent metals. Overall, the variations in elemental composition between different species of the same region were lower compared to variations of the same species from distant regions.The main factors controlling phytoliths elemental composition are the far-range atmospheric (dust) transfer, climatic conditions (humidity), and, in a lesser degree, local lithology and anthropogenic pollution. Despite significant, up to 3 orders of magnitude, difference in TE composition of grass and other plant phytoliths, the dissolution rates of grass phytoliths measured in this study were similar, within the experimental uncertainty, to those of other plants studied in former works. Therefore, elemental composition of phytoliths has relatively minor impact on their preservation in soils.

A comparative study of the effect of various surface treatments on the fracture behavior of aluminum adhesive joints under mode I loading

This study investigates the effect of different surface treatments on the fracture behavior of epoxy-aluminum joints under mode-I loading. Six surface treatments including degreasing, abrasion with varying grit sizes, alkaline etching, acid etching, a combination of alkaline and acid etching, and a combination of abrasion and acid etching were applied to aluminum surfaces before bonding. Surface morphology, roughness parameters, total surface free energy, contact angle, and elemental composition were analyzed. Results showed that the ultimate fracture load and fracture energy initially increased and then decreased with increasing surface roughness. The most effective treatments were found to be acidic etching in combination with alkaline etching and abrasion due to their synergetic effects. These treatments removed the natural oxide layer and created a porous oxide layer, enhancing surface roughness, increasing adhesive-substrate contact areas, and providing more sites for mechanical interlocking. Compared to the degreased specimens, significant improvements were observed, including a 40% and 31% increase in maximum fracture load, a 74% and 53% increase in initiation fracture energy, and a 65% and 47% increase in propagation fracture energy, respectively. Etching treatments demonstrated superior effects on the fracture behavior of aluminum adhesive joints compared to abrasion methods, leading to cohesive failure after etching treatments.

Physio-chemical and Thermal Characterization of Demineralized Poultry Litter using Mechanical Sizing Fractioning, Acid Solvents, and Deionized Water

Poultry litter is an organic waste composed of manure, feathers, and bedding, containing both organic and inorganic elements. Inorganic elements corrode and agglomerate the reactors when poultry litter is thermally converted to biochar, bio-oil or combusted. Demineralizing poultry litter through mechanical size fractioning, acid solvent, and deionized water can decrease the inorganic elements' composition. This study investigates to identify the effects of different demineralization methods on the physio-chemical and thermal characteristics of poultry litter. Statistical analysis (p-value of 0.001) showed that the pretreatment methods reduced the inorganic elements. Mechanically fractioned poultry litter with particle sizes of 1.19-2.36mm and 2.37-5.00mm showed a low inorganic element composition of 7.85% and 9.19% when demineralized. The acid solvent and PL:DI treatments varied their extraction effectiveness depending on the type of inorganic element removed, ranging from 9.65-11.73% of the total inorganic element composition. PL:AcOH treatment had the lowest ash content at 6.89% from 12.33%. Mechanical size fractioned samples had the lowest moisture content, ranging from 2.53% to 4.65%. All the samples had high fixed carbon content except for PL:<1.18mm sample. Volatile matter for PL: AcOH, PL: DI, and PL:2.37-5.00mm samples were higher than the UT: PL and other treated samples. The treated samples noted a low C, high O, S, N, H/C, and O/C and comparable H content with UT: PL sample. Removal of inorganic elements increased the sample's high heating value, with the PL:2.37-5.00mm sample having the highest at 17.60 MJ Kg-1. The FTIR spectra of the demineralized sample revealed a reduction in the transmittance band, indicating the decomposition of the cellulose and hemicellulose structures. TGA-DTG supported the findings by noting a shift in temperature increase with peak temperatures higher than UT: PL sample samples. The degradation occurred at temperatures up to 380°C, noting the degradation of the cellulose and hemicellulose structure of the demineralized poultry litter.

Evaluation of drying kinetics and quality parameters of rosehip pestils dried by three different methods

BACKGROUND: Rosehip fruits cannot be eaten as entire fruits in their fresh feature so they processed into various products including pestils. OBJECTIVE: In the current work, rosehip pestil as a new healthy snack food was developed by using hot air (HA) drying at 55, 65 and 75°C, vacuum (VC) drying at 55, 65 and 75°C with 25 kPa and microwave (MCW) drying at 90 and 180 W. METHODS: The effect of three different drying methods on drying kinetics and quality parameters i.e., total phenolic content (TPC), antioxidant capacity (AC), Hydroxymethylfurfural (HMF) formation, lycopene, β-carotene content, element composition, color, texture and sensorial properties of rosehip pestils was studied. RESULTS: Wang and Singh model was best fitted for MCW drying at 90 W, however Page and Modified Page models were best fitted for other drying conditions. The rosehip pestils dried by MCW drying method had highest drying rate, TPC, AC, lycopene and β-carotene content, element concentration, color values, whereas their HMF content and sensorial properties were not acceptable. Sensory evaluation results indicated that rosehip pestils dried with HA was rated the most acceptable. CONCLUSIONS: It was concluded that rosehip pestil with its sensorial and nutritive properties could be an alternative product for the functional food market. However, it has been seen that the drying methods used alone have some disadvantages. For this reason, it may be possible to eliminate these disadvantages if hybrid drying methods (for example MCW drying followed by HA or VC drying) are preferred in future studies.

Near-surface pedosediments of Takatokwane saline pan, southern Botswana: Properties, pedogenic processes, and inferences of environmental change

Natural pans are an important feature of dry landscapes worldwide. The purpose of this study was to characterize, for the first time, the near-surface pedosediments of the prominent Takatokwane pan in southern Botswana using their physical, geochemical, and mineralogical properties, to explore past and active pedogenic processes, and to interpret the properties of the pedosediments in light of environmental change. Pedogenic parameters including particle size distribution, reaction, electrical conductivity, and organic matter content were determined using routine laboratory procedures. The total elemental composition was analyzed using inductively coupled plasma optical emission spectroscopy and inductively coupled plasma mass spectrometry. The clay mineralogical compositions of the pedosediments were determined using a Bruker D8 Advance X-ray diffractometer. A suite of geochemical coefficients was used to quantify the weathering and pedogenic processes. Granulometric analysis showed that the pedosediments were dominated by fine sand (380 – 890 g/kg). The two pedons were greenish-gray in color at a depth of 140 cm. The elemental abundances followed the order of SiO2 > Al2O3 > Fe2O3 > TiO2. The TiO2/Al2O3 coupled with mineralogy indicated a uniform origin of the parent materials and feldspathic sandstone components, which were redeposited in the pan environment. The geochemical weathering coefficient indicates incipient weathering. Smectite-enriched clay deposits in the basin paved the way for the formation of the vertical layers. At the meso-morphological scale, reworked pedofeatures indicative of clay illuviation and gleisation processes were observed. The dominant pedogenic processes in soils include hydrolysis, lessivage, illuviation, and gleisation. This set of processes indicates the cycles of humid pedogenesis. This study confirmed three cycles of deposition, chemical precipitation, and post-depositional alteration under changing environmental conditions. Evidence from this study points to the seasonality of the environment, which could be explored for an improved understanding of the evolution of the Takatokwane pan and the Kalahari Basin.

Characterization of size-differentiated airborne particulate matter collected from indoor environments of childcare facilities

Inhalation of particulate matter (PM) present in indoor atmospheres has been associated with poor health and wellbeing of occupants. Here we report the characteristics of airborne PM collected from twenty-two air-conditioned childcare centres in Singapore. Airborne PM were collected using cascade impactors and characterized for morphology, elemental composition, endotoxin levels, ability to generate abiotic reactive oxygen species, and oxidative stress-dependent cytotoxicity in BEAS-2B cell lines. The mass concentrations of ultrafine particles (PM0.06-1) were more abundant than that of larger particles (PM1-4, PM4-20, and PM20-35 particles). PM20-35 and PM4-20 were irregularly shaped particles, PM1-4 particles had membranous flaky structures and PM0.06-1 particles were pseudo-spherical with the occasional presence of crystalline structures. Carbonaceous matter dominated PM20-35 particles, and the abundance of inorganic salts, iron and sulfur increased with decreasing PM size. Measured endotoxin levels were especially higher in PM4-20 particles. Compared to other particle size fractions, PM0.06-1 particles generated the highest ROS and were also the most potent in generating intracellular ROS in BEAS-2B cell lines. However, total mass concentrations, elemental compositions, abiotic responses, and PM collected from centres with split air-conditioning systems and no active outdoor air supply (SAC) were not statistically different compared with PM collected from centres with air conditioning with mechanical ventilation (ACMV). In conclusion, our study showed obvious distinctions in mass concentrations, morphology, elemental compositions, and cytotoxic potential of different sized particles collected from childcare centres, where the smallest particles (PM0.06-1) exhibited higher hazard potential.

Aeolian inputs and dolostone dissolution involved in soil formation in Alpine karst landscapes (Corna Bianca, Italian Alps)

Very different soil types occur across a few tens of meters on dolostone, in a never glaciated karst landscape in the Lombard Pre-Alps (Selvino, Italy). This substrate is locally enriched in well-crystallized sand-grained quartz. The quartz content is responsible for the localized genesis of Podzols. Other soil types observed in the area include strongly rubified (Terra Rossa) horizons (paleosols), preserved in the most protected dolostone cracks. Non-rubified Luvisols and Cambisols were observed in karst dry valleys and dolines while Rendzic Leptosols/Phaeozems were common on the steepest slopes. Such a variety of soils was explained assuming different parent materials (dolostone, silica-rich dolostone, with different amounts of aeolian inputs, ascertained using textural properties, mineralogy, micromorphology, total element composition, mass balance calculations, rare earth elements, and stable elements. Many soils were highly polycyclic, with different layers associated to different parent materials and characterized by different pedogenic processes evidencing different ages. We were thus able to distinguish the horizons mainly developed from the dissolution of the dolostone from those formed in Pleistocene loess. The geochemistry of all surface soil horizons, including Podzols and Rendzic Leptosols/Phaeozems, apparently formed from pure or quartz-rich dolostone dissolution, has been influenced by recent aeolian additions (likely Saharan dust), with deeply modified effects according to different pedogenetic processes acting locally. Saharan dust, in fact, significantly increased metal and rare earth elements contents compared to the substrate, also in the youngest and least weathered soil types.

Anaerobic degradation of hexachlorocyclohexane: Factors influencing the reactor start-up

This study examined the anaerobic degradation of technical-hexachlorocyclohexane (t-HCH)-a persistent organic pollutant (POP), using a batch reactor and the influence of pH, active biomass as volatile suspended solids (VSS), total suspended solids, total organic carbon, chloride release, and elemental composition on an Upflow Anaerobic Sludge Blanket (UASB) reactor start-up. Chloride release, a direct indicator of HCH degradation, was measured to confirm the process. During the initial sludge acclimatization, only 49.23 % degradation efficiency was seen after 45 days with an initial concentration of 1.0 g l−1. However, when electron donors and co-substrates were added to the sludge, the degradation time was shortened to 15 days with an increase in efficiency up to 60.17 %. When this adapted sludge was taken in a UASB reactor start up at 100 mg l−1 HCH, this degradation effectiveness was significantly improved when organic loading rate (OLR) was decreased to 50 mg l−1 d−1 assuming 48 h hydraulic retention time (HRT) in a UASB reactor start up at 100 mg l−1 HCH. During the original UASB reactor start-up, 92.37 %, 90.64 %, 85.72 %, and 83.26 % degradation of the alpha, gamma, beta, and delta isomers, with evidence of pentachlorocyclohexene as a transitory intermediate was observed. The major determining variables for reactor start-up were found to be neutral pH, mesophilic temperature, addition of co-substrate (glucose), VSS, HRT, and OLR. The study's innovation is that it examines the efficacy of the degradation process during sludge acclimatization and gives useful details about the variables to consider when starting up a UASB reactor. This research gives a biodegradation trend, which may be required before venturing for anaerobic degradation of recalcitrant substances like t-HCH.

Effect of Fiber Morphology and Elemental Composition of Ananas comosus Leaf on Cellulose Content and Permittivity

The fiber morphology and elemental composition of pineapple leaf fibers were analyzed to understand their effect on the cellulose content and permittivity value. Cellulose fiber was extracted from pineapple leaf via the alkaline treatment method, and the content was determined using the Kurschner-Hanack method. The permittivity value of the developed cellulose fiber was measured based on the waveguide technique in the G-band. The surface morphology of the developed fiber was examined with scanning electron microscopy. Meanwhile, energy dispersive X-ray (EDX) spectroscopy was used to identify the elemental composition of the pineapple leaf fibers. The findings were that the cellulose fibers with the least diameter and distance between fibers exhibited the highest permittivity value, which was 1.85. The EDX analysis demonstrated that carbon was the commonest elemental in all fibers, and was 55 wt.% of the total element composition. Furthermore, the results showed that the permittivity value increased as the carbon composition increased, and decreased as the oxygen composition increased. Hence, the morphological and elemental studies of the cellulose fiber are useful in determining the permittivity value of the cellulose fiber for material development. The high permittivity value of the pineapple leaf fibers is believed to have great potential for use in electronic components.

Detailed characterization of iron-rich tailings after the Fundão dam failure, Brazil, with inclusion of proximal sensors data, as a secure basis for environmental and agricultural restoration

Following the Fundão dam failure in Brazil, 60 million m3 of iron-rich tailings were released impacting an extensive area. After this catastrophe, a detailed characterization and monitoring of iron-rich tailings is required for agronomic and environmental purposes. This can be facilitated by using proximal sensors which have been an efficient, fast, and cost-effective tool for eco-friendly analysis of soils and sediments. This work hypothesized that portable X-ray fluorescence (pXRF) spectrometry combined with a pocket-sized (Nix™ Pro) color sensor and benchtop magnetic susceptibilimeter can produce substantial data for fast and clean characterization of iron-rich tailings. The objectives were to differentiate impacted and non-impacted areas (soils and sediments) based on proximal sensors data, and to predict attributes of agronomic and environmental importance. A total of 148 composite samples were collected on totally impacted, partially impacted, and non-impacted areas (natural soils). The samples were analyzed via pXRF to obtain the total elemental composition; via Nix™ Pro color sensor to obtain the red (R), green (G), and blue (B) parameters; and assessed for magnetic susceptibility (MS). The same samples used for analyses via the aforementioned sensors were wet-digested (USEPA 3051a method) followed by ICP-OES quantification of potentially toxic elements. Principal component analysis was performed to differentiate impacted and non-impacted areas. The pXRF data alone or combined with other sensors were used to predict soil agronomic properties and semi-total concentration of potentially toxic elements via random forest regression. For that, samples were randomly separated into modeling (70%) and validation (30%) datasets. The pXRF proved to be an efficient method for rapid and eco-friendly characterization of iron-rich tailings, allowing a clear differentiation of impacted and non-impacted areas. Also, important soil agronomic properties (clay, cation exchange capacity, soil organic carbon, pH and macronutrients availability) and semi-total concentrations of Ba, Pb, Cr, V, Cu, Co, Ni, Mn, Ti, and Li were accurately predicted (based upon the lowest RMSE and highest R2 and RPD values). Sensor data fusion (pXRF + Nix Pro + MS) slightly improved the accuracy of predictions. This work highlights iron-rich tailings from the Fundão dam failure can be in detail characterized via pXRF ex situ, providing a secure basis for complementary studies in situ aiming at identify contaminated hot spots, digital mapping of soil and properties variability, and embasing pedological, agricultural and environmental purposes.

Mineralogy, elemental composition, and organic matter prediction of wetland soils in the Cerrado biome, Brazil

Context The Cerrado, an area of savannah and wetlands in Brazil, is an important wet ecosystem characterised by organic-rich soils that has important environmental functions. In this work, we hypothesised that the total elemental composition obtained via portable X-ray fluorescence spectrometry (pXRF) could be useful a tool to predict soil organic matter. Aims We aimed to predict the total organic carbon (TOC) content and its fractions (carbon fulvic acid, C-FA; carbon humic acid, C-HA; carbon humin, C-HU) of soils occurring in representative Veredas biome from the Cerrado, Brazil. Methods We collected 144 soil samples from surface (0–20 cm) and subsurface (40–70 cm) layers from six representative Veredas environment located in the Cerrado bome, Triângulo Mineiro region, Brazil. These samples were analysed using a pXRF to obtain the total elemental composition. TOC, C-HA, C-FA, and C-HU fractions were determined by wet-oxidation and titration methods. The pXRF data was correlated with TOC and humic substances and later subjected to simple and multiple linear regression (MLR). Key results The major elements corroborated the mineralogy of wetland soils. TOC and humic substances, mainly C-HU, were reasonably predicted using pXRF data. All humic substances and TOC were strongly correlated to Pb. Thus, by parsimony, TOC could be reasonable predicted exclusively based on Pb concentration. Conclusions We demonstrated that pXRF can be an efficient tool to assess the elemental composition of the Cerrado wetlands soils contributing to still scarce inventory. Further, the elements germane to soil organic matter compounds can be used to predict TOC and its fractions. Implications A detailed characterisation of the Cerrado wetland soils in situ can be successfully performed using pXRF in further studies.

Analysis of Features of Accumulation of Macro- and Microelements in Grass of Hollow of Five-Lobed Flora of Voronezh Region

Studies of the elemental composition of wild raw materials are relevant and significant due to the high efficiency and biological availability of organometallic forms contained in plants. The purpose of the study is to study the macro- and microelement composition of motherwort herb five-lobed natural phytocenosis of the Voronezh region. Raw materials were harvested during the flowering of the plant in the Voronezh State Natural Biosphere Reserve. The microelement composition of the samples was studied mass spectroscopically on an ELAN-DRC instrument. It was revealed that the content of the microelement complex is 5.8%, 59 elements were determined. Macroelements make up 96.31% of the total elemental composition of the five-lobed hollow grass. The macroelements are based on potassium (more than 30 mg/g), as well as calcium (more than 16 mg/g). Essential trace elements make up 3.08% of the total mineral complex of the five-lobed hollow grass. Among them, the highest content was noted for silicon (more than 1.4 mg/g), iron (more than 0.1 mg/g). The content of regulated heavy metals and arsenic in the grass of the five-bladed dummy complies with the requirements of regulatory documentation. Lead, mercury, cadmium and arsenic account for 0.0008% of the total mineral complex of raw materials. The share of toxic and little-studied elements in the total mineral complex of the grass of the five-lobed dummy is 0.61%. The highest content was observed for aluminum (191.4 g/g), strontium (65.2 g/g), barium (70.3 g/g), titanium (19.2 g/g), rubidium (5.68 g/g). The high ability of the five-lobed puberty grass to accumulate phosphorus, potassium, copper, zinc, cadmium from the soil, as well as a significant opportunity to accumulate calcium, magnesium, molybdenum, nickel, strontium and tellurium, is shown.

ULTIMATE COMPOSITION OF NATURAL WORMWOOD IN VORONEZH REGION

Studies of the ultimate composition of wild-growing raw material are relevant due to the high efficacy and bioavailability of organometallic forms contained in plants. The available information on the abundance of elements in the medicinal plant raw material (Voronezh region) showed that studies were carried out mainly on several elements. It prevented from determining the complete chemical composition of plants and describing the accumulation of the entire mineral elements complex.
 The purpose of the paper is to study how macro and trace elements are accumulated in natural wormwood in Voronezh region.
 Materials and Methods. Raw material procurement was carried out during the blooming in the Voronezh State Nature Biosphere Reserve. The method of mass spectrometry was used to study the trace element composition of the samples, ELAN-DRC mass spectrometer.
 Results. The authors revealed that the trace element content was 4.4 %, 59 elements were determined. Macro elements made up 96.03 % of the total elemental composition of wormwood. Potassium (>25 mg/g) and calcium (>10 mg/g) were the main macro elements. Essential trace elements made up 3.49 % of the total wormwood complex. Among them, silicon (>1.2 mg/g) and iron (>0.1 mg/g) ranked the largest. The content of normalized heavy metals and arsenic in wormwood satisfied the regulatory requirements. Lead, mercury, cadmium and arsenic accounted for 0.0017 % of the total raw material mineral complex. The proportion of toxic and understudied elements in the total mineral wormwood complex was 0.48 %. The highest content was noted for aluminum (135.6 µg/g), rubidium (27.66 µg/g), strontium (24.95 µg/g), barium (11.98 µg/g), and titanium (9.52 µg/g). It was noted that wormwood also accumulated phosphorus, potassium, copper, zinc, cadmium, molybdenum, calcium, magnesium, nickel, arsenic, rubidium, tin and strontium from the soil.

Geochemistry signatures of mercury in soils of the Amazon rainforest biome

Mercury (Hg) toxicity in soils depends on Hg species and other physical and chemical attributes, as selenium (Se) hotspots in soils, particularly relevant in Amazonian soils. The study of Hg species and their relations in representative locations of the Amazon rainforest biome is critical for assessing the potential risks of Hg in this environment. This work aimed to determine the concentration of total Hg and its species (Hg0, Hg22+ and Hg2+), and to correlate Hgtotal concentration with total elemental composition, magnetic susceptibility, and physicochemical attributes of Amazon soils. Nine sites in the Amazon rainforest biome, Brazil, were selected and analyzed for their chemical, physical, and mineralogical attributes. The clay fraction of the studied Amazon soils is dominated by kaolinite, goethite, hematite, gibbsite, and quartz. Mica was also found in soils from the States of Acre and Amazonas. Hgtotal ranged from 21.5 to 208 μg kg−1 (median = 104 μg kg−1), and the concentrations did not exceed the threshold value established for Brazilian soils (500 μg kg−1). The Hg2+ was notably the predominant species. Its occurrence and concentration were correlated with the landscape position and soil attributes. Hgtotal was moderately and positively correlated with TiO2, clay, and Se. The findings showed that geographic location, geological formation, and pedological differences influence the heterogeneity and distribution of Hgtotal in the studied soil classes. Thus, a detailed characterization and knowledgment of the soil classes is very important to clarify the complex behavior of this metal in the Amazon rainforest biome.

Spatial and seasonal trends of trace metals in the surficial sediments from off Kochi - Geochemistry and environmental implications.

Fifty four sediment samples representing pre and post-monsoon seasons were collected along a transect from off Kochi, lying between the latitudes 9°57'59.5″-9°54'30.4″ and longitudes 76°11'7.04″-75°38'50.3″ of the South eastern Arabian Sea. The present study investigates the levels of trace metals (Zn, Cd, Pb, Cu, Fe, Ni, Mn, Co and Cr), total organic carbon (TOC), total inorganic carbon (TIC), elemental composition and grain size to assess the extent of environmental pollution and to discuss the distribution of these trace metals in the surficial sediments. Sediment pollution assessment was done using the Contamination factor (C.F), Geoaccumulation Index (Igeo), Enrichment Factor (EF), and Pollution Load Index (PLI). The majority of trace metals analysed in this study exhibited the highest concentrations at stations 1, 2 and 3 where the land-based anthropogenic input was found to be maximum.

Silica crystallinity: Characteristics and controlling factors in marine shale of the upper Yangtze area, China

The quartz crystallinity index (QCI) was applied to quantitatively characterise the crystallinity features of silica within the marine shale of the upper Yangtze area. A total of 67 samples, including 63 shale samples, 3 quartz vein samples, and 1 artificial quartz sample as reference, were applied in QCI calculation by X-ray diffraction (XRD). Furthermore, based on the identification and classification of graptolite biozones, a series of experimental analyses, including the total organic carbon (TOC) content, bitumen reflectance, and elemental composition, were conducted to determine the silica origin and controlling factors of crystallinity. The results indicated that biogenic silica in marine shale intervals had an obviously lower crystallinity than silica of other origins. The quartz vein in shale intervals presented the highest silica crystallinity. Silica that experienced a low diagenesis intensity exhibited the lowest crystallinity. Furthermore, biogenic silica in a state of overpressure had a much lower crystallinity than that under normal pressure. The crystallinity of silica in marine shale of the upper Yangtze area is affected by origin, diagenesis intensity, and overpressure. From the perspective of QCI, the Chengkou area is probably the next favourable area for shale gas exploration and development.

The role of tephra additions on development of incipient soils from Livingston Island (Antarctic Peninsula) revealed by environmental magnetism

Soils from maritime Antarctica store important information about initialization of pedogenesis and role of the major factors of soil formation. Deciphering the interplay among all contributing agents is however challenging and needs involvement of an interdisciplinary approach. The main aim of our study is to contribute to this goal by assessing mineral magnetic signature of a collection of topsoils from Livingston Island and investigate the major contributing factors, determining their magnetic properties. A set of 23 soil samples from Hurd Peninsula at Livingston Island were studied. Magnetic susceptibility and frequency dependent magnetic susceptibility measurements, anhysteretic remanent magnetization, hysteresis measurements at room temperature and low temperatures were carried out. Identification of magnetic minerals was achieved through thermomagnetic measurements of magnetic susceptibility and analysis of Isothermal Remanence acquisition. Magnetic measurements were supplemented by geochemical analyses of total elemental composition by X-ray fluorescence spectrometry and selective Fe- and Al- extractions by Dithionite-Citrate-Bicarbonate and ammonium oxalate. Magnetic results indicate that composition of iron oxides in soils differs significantly from that of bedrocks by the presence of titianomagnetite fractions with high- and medium Ti-content, while rocks’ mineralogy is dominated by paramagnetic minerals or by coarse grained multi-domain magnetite. Titanomagnetite phases were ascribed to the input of tephra additions from the nearby Deception Island. Based on the magnetic susceptibility measurements at low temperatures it was concluded that a fraction of fine grained magnetite is present in soils, in addition to titanomagnetite. Geochemical data reveal differences between the composition of soils and main rock lithologies, which is also assigned to tephra input. Amount of ammonium-oxalate extractable iron and aluminum were higher than that extracted by dithionite, which was attributed to fast tephra weathering in cold polar climate.

Особенности накопления макро- и микроэлементов в траве тысячелистника обыкновенного флоры Воронежской области

Researches of elemental composition of wild-growing raw materials are actual and significant because of high efficiency and bioavailability of their metal-organic forms contained in plants. Available data on the content of elements in medicinal plant raw materials of the Voronezh region showed that studies are conducted mainly on a few elements, which does not allow to determine the full chemical composition of plants and to describe the specificity of accumulation of the whole complex of minerals in them. Objective. The aim of the investigation was to study the accumulation of macro- and microelements in common yarrow herb of natural phytocenosis of the Voronezh region. Materials and methods. Preparation of medicinal plant raw materials was carried out during the flowering of the plant in the Voronezh State Natural Biosphere Reserve. The microelement of medicinal plant raw materials was determined by mass spectroscopy with inductively coupled plasma on the ELAN-DRC device. Results. It was found that the content of microelement complex is 3.28%, 59 elements were determined. Macronutrients account for 93.78% of the total elemental composition of common yarrow herb. The basis of macronutrients is potassium (more than 14 mg/g), and calcium (more than 10 mg/g). Essential microelements make up 5.51% of the total mineral complex of the common yarrow herb. Among them the highest content was noted for silicon (more than 1.6 mg/g), iron (more than 0.1 mg/g). The content of the rationed heavy metals and arsenic in the herb common yarrow corresponds to the requirements of the normative documentation. The proportion of toxic and understudied elements in the total mineral complex of common yarrow herb is 0.71%. The highest content was noted for aluminum (116.5 µg/g), strontium (81.6 µg/g), titanium (12.5 µg/g), rubidium (9.5 µg/g), barium (9.31 µg/g). The high ability of common yarrow herb to accumulate phosphorus, potassium, copper, zinc, molybdenum, strontium from soil was shown. Conclusion. The data obtained are of great interest and can serve as a basis for further research with the aim of using their results in medical and pharmaceutical practice to create drugs and biologically active additives for correcting physiological norms of element content in the human body.