A sustainable solution for the global construction industry can be partial substitution of Ordinary Portland Cement (OPC) by use of supplementary cementitious materials (SCMs) sourced from industrial ...end-of-life (EOL) products that contain calcareous, siliceous and aluminous materials. Candidate EOL materials include fly ash (FA), silica fume (SF), natural pozzolanic materials like sugarcane bagasse ash (SBA), palm oil fuel ash (POFA), rice husk ash (RHA), mine tailings, marble dust, construction and demolition debris (CDD). Studies have revealed these materials to be cementitious and/or pozzolanic in nature. Their use as SCMs would decrease the amount of cement used in the production of concrete, decreasing carbon emissions associated with cement production. In addition to cement substitution, EOL products as SCMs have also served as coarse and also fine aggregates in the production of eco-friendly concretes.
In this study, we introduce a novel approach using correlative analysis techniques to unravel detailed insights into the environmental influences on crystal growth. Tabular and bipyramidal wulfenite ...samples from the Mežica mine in north-eastern Slovenia were analysed to combine the morphological aspects of crystal growth with the atomic-resolution reconstruction of the positions of lead (Pb) and molybdenum (Mo) atoms in the parent crystal lattice. These combined data also allow us to present the formation mechanism that enables the development of bipyramidal or tabular morphologies in wulfenite. The bipyramidal and tabular crystals are chemically pure wulfenite (PbMoO
), as confirmed by various advanced diffraction and spectroscopy techniques. However, each habit includes multiple inclusions, mostly consisting of carbonates, Pb-Fe oxides, Pb oxides and, more rarely, Pb vanadate (descloizite). The differences in the morphologies can be attributed to compositional changes during precipitation from a meteoric solution and thus, we propose a growth mechanism consisting of three different phases of growth. This innovative approach emphasises the importance of understanding the origin of crystal habits, as can help to decipher how external influences can affect the crystal structure and its surface, leading to the dissolution of preferred surfaces and the selective release of Pb and Mo.
Heavy metal abundance and potential environmental risks are reported for surface sediments (n = 21) from the Port of Koper area, Republic of Slovenia. The enrichment factor (EF) indicates minor ...enrichment in arsenic (As), cadmium (Cd), copper (Cu), molybdenum (Mo), lead (Pb), antimony (Sb), and zinc (Zn), moderately to severely enriched with nickel (Ni). The trace metal chemistries, in the context of sediment quality guidelines (SQG), imply adverse threshold effect concentrations (TEC) and probable effect concentrations (PEC), for Ni only. Sediment sequential leaching experiments demonstrated that the majority of heavy metals were of natural lithogenic origin and low bioavailability. The heavy metals’ potential for “Risk Assessment Code” values exhibited no or low anthropogenic environmental burden, with the exception of Mo.
In the Republic of Macedonia, information about rare earth elements (REEs) distribution patterns, transportation and speciation characteristics (from soil to plants) is very rare. Therefore, the ...concentrations of REEs in Kočani paddy soils and rice samples from the Republic of Macedonia were measured and evaluated. The elevated concentrations of REEs in paddy soils can be explained by contributions from acidic and intermediate igneous rocks, which are one of the main source materials for Kočani paddy soils. Low percentages of REEs were bound to the water-soluble and exchangeable fractions, revealing low mobility of REEs in the investigated paddy soils. Furthermore, small amounts of REEs were detected in rice (Oryza sativa L.) grain samples. The calculated transfer values (TF) for REEs in rice samples were also very low, confirming a small accumulation of REEs (La, Ce, Pr, Nd and Sm) by the studied crops and in the Kočani soil–plant system.
► The concentrations of REEs in Kočani paddy soils and rice samples were evaluated. ► The elevated values of REEs in soils originated from nearby igneous rocks. ► Low percentages of REEs were bound to the water soluble and exchangeable fractions. ► The REE values in rice grains and calculated transfer factors were also very low. ► The results given are confirming the weak accumulation of REEs in the Kočani crops.
Hypersaline environments are among the most vulnerable coastal ecosystems and are extremely noteworthy for a variety of ecological reasons. Comprehensive assessment of metal(oid) contamination in ...hypersaline sediments from Sečovlje (Northern Adriatic, Slovenia) was addressed by introducing the detrital and diagenetic mineralogy and geochemical properties within the solid sediment material. Close associations between Fe/Mn oxides and oxyhydroxides with As, Cr, Ni, Pb and Zn, and between organic matter with Cu, Pb and Zn were confirmed using X-ray powder diffraction, SEM-EDS and ICP emission spectrometry analysis. Possible incorporation or adsorption on the crystal lattices of clay minerals (As, Cr, Pb, Sn and Zn), halite (As) and aragonite/calcite (Cd, Cu, Pb, Sr and Zn) were also detected. All presented correlations were highlighted by various statistical analyses. The enrichment factor (EF) values showed a low degree of anthropogenic burden for As, Bi, Hg and Zn, while Cd, Cr, Cu, Ni, Pb, Sn and Sr originated from the geological background. These results emphasise that a detailed mineralogical and geochemical characterisation of solid (especially detrital and diagenetic) sediment particles is crucial in further understanding the metal(oid) translocation within the hypersaline ecosystems.
Marbles in Pohorje occur in lenses and smaller bodies in the southern and southeastern part of the massif. Marbles are very pure, predominantly calcitic and rarely calcitic-dolomitic, containing a ...maximum of 5 % of non-carbonate mineral phases. The latter comprise pyroxenes (diopside), amphiboles (tremolite), olivines (forsterite) in places replaced by serpentine, quartz, feldspars (potassium feldspars and plagioclases), epidote, zoisite, vesuvianite, scapolite, muscovite, biotite partly replaced by chlorite, phlogopite, rare grains of titanite, rutile, zircone, apatite, and small grains of ferric oxides and sulfies. Calcite exhibits intensive deformational e-twinning whereas dolomite is undeformed and untwined. All four known types of mechanical twins in calcite were recognized: thin Type I twins, straight thick Type II twins, curved, lensoid and tapered thick Type III twins, and thick patchy Type IV twins. Type III twins are the dominant mechanical twins in the Pohorje marbles indicating the temperature of deformation somewhat above 200 °C. Since they lack signs of grain boundary recrystallization, we assume that the twinning was followed by a decrease temperature during exhumation. With increasing temperature the process of recrystallization along calcite grain becomes pronounced. Small individual untwined calcite crystals are progressively replacing bigger calcite grains. In few examples second generation of Type I deformational twins develop in recrystallized calcite grains, which also implies lowering of temperature due to exhumation.
This research focuses on determination of the mineralogical composition, geochemical characteristics and evaluation of pollution status of the Makirina Bay sediments. Calculated enrichment factor ...(EF) values show no enrichment (< 1) for Cd, Ni, and Zn, minor enrichment (< 3) for As, Cu, and Pb, and minor to moderate enrichment for Mo. The results of the sequential leaching procedure for the aforementioned potentially toxic elements (PTE) indicates that the mobility and bioavailability characteristics of the PTE studied declined in the following order: Mo > Cd > Pb > Ni > Zn > Cu > As. Principal component analysis (PCA) and correlation analysis confirmed the PTE distribution depends mainly on the geogenic mineral components and anthropogenic activities in the areas surrounding the bay. Calculated transfer factor (TF) values from sediment to seagrass Cymodocea nodosa (C. nodosa) were < 1, showing that despite the results of the sequential extraction procedure, PTE transfer from sediment to roots was not effective.
This chapter represents the mineralogical, geochemical and isotopic characteristics of recent lacustrine sediments, shells of the Anodonta cygnea and fish species (Rutilus rutilus dojranensis) from ...the Lake Dojran (FY Republic of Macedonia, southern part of the Serbo-Macedonian Massif (SMM)) which provide indirect evidence regarding biomineralization and calcification processes as well as various geological problems. Environmental pollution can seriously contribute to different biological processes concerning the condition of physiological secretion of carbonate material into the shells. For comparison, sediments and fish species V. melanops from the Lake Kalimanci, located in northern part of the SMM, were also implicated into the study. X-ray powder diffraction (XRD), inductively coupled plasma mass spectrometry (ICP-MS) and C and O stable isotope analyses were performed, and thereupon enrichment factor (EF) values were calculated. The XRD results revealed close association of sediment mineralogy with the prevailing metamorphic, volcanic and igneous rocks of the region surrounding both lakes (Dojran and Kalimanci). According to the EF value results, surficial Lake Dojran sediments are little enriched with Co, Cr, Cu, Pb, and Zn, moderately enriched with Au, Ni and Sb, moderately severely enriched with Au, severely enriched with Sb and very severely enriched with As. This elemental enrichment originates from various geogenic (geological background and polymetallic mineralization) and anthropogenic (tourism, traffic, coatings, untreated wastewater discharge and agrochemicals) sources. Calculated EF revealed that surficial sediments from Lake Kalimanci are extremely severe enriched with Pb, Zn, and Cd, meanwhile As and Cu shows very severe enrichment. Comparing to Lake Dojran, calculated EF is much higher in Lake Kalimanci than in Dojran. Stable isotope signature results showed that Lake Dojran sediments were strongly influenced by evaporation effect. Their δ18O values range from -5.60 to +1.49 ‰ and the δ13CVPDB composition range from -6.45 to -1.65 ‰. Shells Anodonta cygnea are mainly composed from mineral aragonite and their δ18O values varies between 0.43 ‰ and +1.94 ‰, and δ13CVPDB between -2.48 to -1.72 ‰. δ18O signature in shells might be explained by precipitation of the carbonate from isotopically heavier oxygen lake water. The unussualy heavy skeletal oxygen suggested calcification at the elevated temperature and evaporation. Analyses also identified particularly high levels for Cr, Hg, Ni and Pb in fish (V. Melanops) and frog (R. Temporaria) samples from Lake Kalimanci with mean values µgkg-1: 1090 – 6.5, 339 – 117, 567 – 5100 and 1127 – 435, respectively. Meanwhile, the contents of Cr, Hg, Ni and Pb in fish samples (R. rutilus dojranensis) from Lake Dojran are a bit lower µgkg-1: 2320, 1690, 700 and 50.
Purpose
Hypersaline environments are extremely vulnerable and important ecological niches. Because much knowledge has focused on the distribution of heavy metals in these areas, the detailed behavior ...of key major elements in hypersaline environments has not been elucidated in detail.
This research aims to define the distribution, translocation pathways, and mobility patterns of the major elements in hypersaline sediments and halophytes.
Materials and methods
Samples of
Sarcocornia fruticosa
plants were collected from evaporation (ES) and crystallization (CA) sites in the Sečovlje Salina area (Republic of Slovenia). The major element contents were measured by digestion in HNO
3
then aqua regia and analyzed by ICP-MS for ultra-low detection limits. Rhizo-sediments from EA and CA were processed using sequential extraction analysis to determine the precise fractionation of Al, Ca, Fe, K, Mg, Mn, and Na. To determine the translocation patterns of individual major elements in
S. fruticosa
, two indices were calculated: bioconcentration (BCF) and translocation factor (TF). Differences and similarities between samples and elements were highlighted using Statistica VII and Grapher 8 statistical software and Ward’s method, respectively.
Results and discussion
The obtained results confirmed that halophyte plants take up large amounts of the essential micronutrient Na due to high salinity, and that macronutrients (Ca, Mg, P, and S) are intensively translocated from the roots to the upper parts of the plant. The overall trend in translocation signature for major elements, distinguished by BCF and TF factor calculations, emphasizes that root tissues accumulate a significant amount of major elements and that accumulation depends on individual major elements. It also showed that the major elements Ca, Mg, Na, P, and S are highly translocated within plants, while the mobility of Al, Fe, and K is limited.
Conclusions
Our results suggest that the major elements are vital macronutrients for halophytes, but their accumulation in the roots and further translocation within the plant depend on individual elements and their dynamics. The translocation pattern of the major elements can be justified as follows: Ca is an essential element for plant growth, maintenance, and membrane integrity; Mg is a specific component of chlorophyll; Na is present because of the hypersaline environment; P is a key component of plant metabolic processes; S represents an important component of enzymes and other key proteins; Al and Fe are preferentially accumulated in roots; and plant leaves are generally undersupplied with K. The presented results are of great importance for the general knowledge and use/application of halophytes in agriculture and biotechnology.
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