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Povzetek: Mineral CO2 sequestration is a promising carbon capture and storage approach based on the chemical reaction of CO2 with alkaline materials containing Ca- and Mg-rich (hydr)oxides and silicates. This results in the formation of relatively insoluble and storable carbonates. This study investigates six ashes of different origins and chemical compositions to assess their CO2 sequestration potential and leaching behavior, offering insights into their environmental impact and potential risks. The carbonation experiments were conducted under controlled laboratory conditions and the CO2 sequestration capacity was quantified using a pressure calcimeter, supported by thermogravimetric analysis. Wood ashes and ash from the co-combustion of biomass from a paper mill showed the highest carbonation potential, with CO2 sequestration capacities between 344.8 and 432.3 g CO2 per kg of ash and carbonation efficiencies between 82.4 % and 94.4 %. In addition to the high sequestration capacity of the ashes, carbonation was found to affect the leaching behavior of the ash in the environment by changing its mineralogical composition. The process consistently reduced pH and generally decreased the leaching of certain trace elements, except for Mo, and Cr. Nevertheless, the reduction in the leachability of several elements suggests a partial environmental benefit of carbonation. The findings highlight the dual functionality of the carbonation: it provides a viable route for the permanent binding of CO2 and can enhance the stabilization of industrial residues. However, the persistence of metal leaching indicates that its overall effectiveness in mitigating environmental risks associated with residue disposal or reuse remains material-dependent.
Ključne besede: enforced carbonation, maximum sequestration capacity, leaching, heavy metals, mineralogy, bio-based ash
Objavljeno v DiRROS: 13.01.2026; Ogledov: 176; Prenosov: 147
Celotno besedilo (5,37 MB)
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Povzetek: Harmonization of monitoring protocols and analytical methods is a crucial issue for transnational marine environmental status assessment, yet not the only one. Coherent data management and quality control become very relevant when environmental status is assessed at regional or subregional scale (e.g., for the Mediterranean or the Adriatic Sea), thus requiring data from different sources. Heavy metals are among the main targets of monitoring activities. Significant efforts have been dedicated to share best practices for monitoring and assessment of ecosystem status and to strengthen the network of national, regional and European large data infrastructures in order to facilitate the access to data among countries. Data comparability and interoperability depend not only on sampling and analytical protocols but also on how data and metadata are managed, quality controlled and made accessible. Interoperability is guaranteed by using common metadata and data formats, and standard vocabularies to assure homogeneous syntax and semantics. Data management of contaminants is complex and challenging due to the high number of information required on sampling and analytical procedures, high heterogeneity in matrix characteristics, but also to the large and increasing number of pollutants. Procedures for quality control on heterogeneous datasets provided by multiple sources are not yet uniform and consolidated. Additional knowledge and reliable long time-series of data are needed to evaluate typical ranges of contaminant concentration. The analysis of a coherent and harmonized regional dataset can provide the basis for a multi-step quality control procedure, which can be further improved as knowledge increases during data validation process.
Ključne besede: contaminants, data management, harmonization, Adriatic Sea, Ionian Sea, pollution, assessment, heavy metals
Objavljeno v DiRROS: 22.07.2024; Ogledov: 1314; Prenosov: 722
Celotno besedilo (2,39 MB)
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Povzetek: In this work, the contents and spatial distributions of 19 elements (Ag, Al, B, Ba, Ca, Cr, Cu, Fe, K, Li, Mg, Mn, Na, Ni, P, Pb, Sr, V, Zn) in the soil of the western part of North Macedonia (Mavrovo-Rostuše region) are presented. For this purpose, a total of 66 soil samples were collected from 33 locations (33 samples of topsoil, 0-5 cm, and 33 samples of subsoil, 20-30 cm). All samples were analysed by inductively coupled plasma - atomic emission spectrometry (ICP-AES) after complete digestion with four acids (HNO3, HF, HClO4 and HCl). The obtained results were statistically evaluated and spatial distribution maps for all analysed elements were also prepared. Factor analysis was performed to reduce the number of data used and new synthetic variables (factors) were identified. Through the application of factor analysis, three geochemical associations were identified: Factor 1 (Zn, K, Cu, Fe, and Li), Factor 2 (Cr, Ni, and Mg) and Factor 3 (Ca and Al). From the obtained data and the maps of spatial distribution, it could be concluded that the distribution of the analysed elements is related to the lithology of the region. Thus, it was found that the higher content of elements of Factor 1 occurs in the eastern and southern part of the study area (middle and lower reaches of the Radika River and along the Mala River), where Mesozoic and Paleozoic carbonates as well as Paleozoic shales and Paleogene flysch prevail. Factor 2 (Cr, Ni and Mg) also represents a lithogenic association. The highest contents of the elements in both soil layers were found in the areas where Paleozoic sandstones and shales (village of Lazaropole and the area around the Mavrovo Lake) and Paleogene flysch (Rostuše village) predominate. Factor 3 (Ca and Al) also represents lithogenic association of elements. The highest content of these elements was found in the northwestern part of the study area (village of Žirovnica and along the Berička River) and in the northeastern region above the village of Brodec where Mesozoic carbonates and Paleogene flysch dominate.
Ključne besede: soil, heavy metals, spatial distribution, Mavrovo-Rostuše region, North Macedonia
Objavljeno v DiRROS: 04.01.2024; Ogledov: 1518; Prenosov: 461
Celotno besedilo (1,90 MB)

Povzetek: In this work, the distribution of chemical elements in samples of surface water from the Strumica River Basin, North Macedonia, was studied. The water samples were collected from a total of twelve sites. In addition to the Strumica River, samples were collected from its tributaries: Bansko, Dabile, Turija, Vodoča, Radoviška, and Injevska. The determination of the concentration of 21 elements (Ag, Al, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Mo, Na, Ni, P, Pb, Sr, V, and Zn) was performed by inductively coupled plasma - atomic emission spectrometry (ICP-AES). All detailed information on the studied items was statistically processed using Stat Soft, 11.0 software. Using the obtained data on the concentration of the studied elements, descriptive statistical analysis of the values ​​for the concentration of the elements was performed. A map of spatial distribution was obtained for each element. The obtained results show that the concentrations of the studied elements in the surface water samples are relatively low and the distribution of most of the elements follows the lithology of the study area.
Ključne besede: rivers, surface water, heavy metals, Strumica River Basin, North Macedonia
Objavljeno v DiRROS: 20.07.2023; Ogledov: 1564; Prenosov: 547
Celotno besedilo (2,11 MB)

Povzetek: The EU Water Framework Directive requires the monitoring and evaluation of surface water sediment quality based on the assessment of risk posed by contamination on the biotic receptors. Floodplain sediments are important receptors of potentially toxic element (PTE) contamination from the upstream catchment areas, and floodplains host climate-sensitive riverine ecosystems and fertile agricultural areas at the same time. This study investigates the effect of PTE contamination on microbial communities in floodplain sediments and soils using the fast, inexpensive and reliable fluorescein diacetate (FDA) method in order to estimate its applicability for sediment quality monitoring and preliminary toxicity-based risk assessment. Sediment and soil samples were collected from the actively flooded alluvial plain and the river terrace areas along a 130-km stretch of the large Drava River floodplain known to be widely contaminated by historical mining, smelting and the associated industry in the upstream Alpine region. Results of detailed data analysis show that the total microbial activity represented by the measured FDA values is related to PTE (As, Cu, Zn, Cd, Pb) concentrations, but this relationship shows significant heterogeneity and depends on the spatial location and on the soil properties such as organic matter content, dissolved salt and nutrient content, and it is specific to the toxic elements. Results show that some microbe species appear to be able to adapt to the elevated PTE concentrations in toxic soil micro-environments, over time. Despite the observed heterogeneity of microbial activity, the results revealed a breakpoint in the FDA dataset around the FDA = 3 FC (fluorescein concentration) value suggesting that microbial activity is controlled by thresholds.
Ključne besede: potentially toxic elements, fluorescein diacetate activity, heavy metals, contamination, biological activity
Objavljeno v DiRROS: 25.08.2022; Ogledov: 1937; Prenosov: 589
Celotno besedilo (6,23 MB)