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A study of the behavior of selected metals in affected environments using an isotopic approach
Santos Baieta, Rafael ; Mihaljevič, Martin (advisor) ; Navrátil, Tomáš (referee) ; Tejnecký, Václav (referee)
Metals of anthropogenic origin have consistently polluted the environment. This thesis focuses mainly on highly contaminated soils or tree rings near mines and smelters in Sub-Saharan Africa. However, Portuguese soils were also assessed to study Pb isotopes in post-fire soils. The tracing capabilities of Pb isotopic ratios were employed to determine contamination sources and to evaluate the potential of pine trees as an environmental archive. Several analytical methods were applied, such as catalytic oxidation, Q-ICP-MS, ICP-OES, FEG-SEM/EDS, EPMA, XRD, etc. Soils near smelters located in three different cities [Kabwe (Pb-Zn), Luanshya (Cu, Co), and Selebi Phikwe (Ni, Pb)] exhibited concentrations of metals greatly exceeding those deemed acceptable by the competent authorities. In Kabwe, for example, concentrations of Pb exceeded 16 000 mg kg-1 . In all sites, contamination was shown to be significant only in the upper ±15 cm of soil. Samples of soils taken in remote locations were always clear of contamination. In Luanshya, metal(oid) bearing particles found in the soils were typically spherical and composed of rapidly cooled sulfides and oxides in the flue gas chambers of the local smelter. These were present only in the topsoil. The tree ring record of pine trees in Kabwe was shown to mimic the...
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Chemical composition of photovoltaic panels
Koudelová, Marta ; Šebek, Ondřej (advisor) ; Tejnecký, Václav (referee)
The bachelor's thesis is focused on the issue of photovoltaic cells and panels. The literature search was formed from selected available literature with the purpose to characterize different types of the crystalline silicon photovoltaic cells and thin-films photovoltaic cells and describe the application of photovoltaic cells in the world and in the Czech Republic. In the next part of this thesis is a summary of current knowledge about recycling of photovoltaic cells and other utilization of layers and their possible impact on the environment. The practical part of the thesis deals with selected samples of PV panels. A few samples of photovoltaic panels were taken for chemical analyses. Chemical analyses are performed of the five samples of the photovoltaic panels. The results of chemical analyses were compared with acquired data from the literature. The results of the multielementary analysis of selected samples was that the photovoltaic panels contain a risk elements (e. g. As, Cd, Sb, Mo). The PV panels also contain economics utilizable elements (Ag). Content of silicon is up to 78,18 % SiO2. Key words Photovoltaic panel, photovoltaic cell, chemical analysis, risk elements, recycling
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Distribution of selected elements in soils of urban parks in Prague and Brno
Šimeček, Martin ; Mihaljevič, Martin (advisor) ; Tejnecký, Václav (referee)
Prague and Brno belong to one of the most contaminated cities of Czech Republic. The main objective of this study was to compare PGE contents and concentrations of risk elements (Zn, Cd, Pb, Cu, As, Sb, Hg) in the soils of both cities's municipal parks. Soil samples were taken from depths of 0-10 cm, 10-20 cm and 20-30 cm. Besides soil samples, the sand samples from children sandpits were taken from depth 0-30 cm. In 52 samples of soil and sand Pd, Pt and Rh contents were determinated by ICP- MS after Ni-S fire assay procedure. Soil samples were additionally analysed on Pb isotopic composition. Higher PGE contents were determined in Prague; the highest contents were measured at location of Ortenovo náměstí (50,5 μg·kg-1 Pt, 33,9 μg·kg-1 Pd a 11,3 μg·kg-1 Rh). Elevated PGE concentrations were found in the upper layers of most soils in both cities. Elevated contents of risk elements were determined at locations with high traffic density. Most of samples showed that contents of risk elements decrease with depth. The highest concentrations reached Zn (394 mg·kg-1 ), Pb (290 mg·kg-1 ) and Cu (181 mg·kg-1 ). In Prague, the isotopic ratios 206 Pb/207 Pb vary from 1,136 to 1,181; in Brno from 1,161 to 1,192. Measured isotopic ratios suggest contamination both from gasoline and ore combustion. Key words:...
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Distribution of mercury in soils around current and historical sources of mercury emissions
Petlachová, Zuzana ; Navrátil, Tomáš (advisor) ; Tejnecký, Václav (referee)
This thesis provides an overview of mercury distribution in the forest soils located in vicinity of historical and current mercury emission sources. The sites were chosen around Bohemian Karst due to presence of emission source, i.e. iron production processes, cement plants, lime processing plants. The chosen sites were near municipalities of Králův Dvůr, Radotín and Hrádek u Rokycan. From these sites the soils samples were collected from organic and mineral horizons. Average mercury concentration in organic horizons was 288 µg.kg-1, organo-mineral horizons A contained 241 µg.kg-1, anthropogenic horizons M 287 µg.kg-1 and horizons B 56 µg.kg-1 only. The relations among mercury and soil components were tested. Strong link between mercury, soil organic matter (SOM) and sulfur was found. The result indicated that the origin of mercury in soil samples was atmospheric deposition rather than bedrock. High concentrations of oxalate extractable aluminum, iron and manganese in mineral horizons have been explained as the cause of bedrock weathering. Powered by TCPDF (www.tcpdf.org)
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Application of sequential extraction procedure for determination of antimony speciation in contaminated soils
Tejnecký, Václav
The city of Příbram (Czech Republic) is located in a traditionally industrial, mining and metallurgical district. During the hundred years of these activities, the area has been severely contaminated by toxic elements, including antimony (Sb). Generally, the acceptable Sb concentration limit in soils is supposed to be 5 mg.kg-1 . In the Příbram area, the Sb concentrations in soils are exceeding more than 200x this limit. The main source of Sb in the studied environment is related to emissions from primary and secondary Pb smelting. This study is focused on application of sequential extraction procedure (initially used by Wenzel et al., 2001 for As speciation) to forest and tilled soil profiles heavily polluted by Sb and located in the vicinity of the Příbram smelter (1 km). Maximum concentrations were 1720 mg Sb.kg-1 and 467 mg As.kg-1 in horizon B of forest soil. In the tilled soil, significantly lower concentrations of Sb and As were determined (100 mg Sb.kg-1 and 170 mg As.kg-1 in horizons A and B, respectively). These results can be related to higher interception of smelter emissions by tree canopies in the forest system and/or to intense agricultural practice in tilled soils (tillage, biomass loss,...). In the tissues of plants growing on these contaminated soils, the Sb concentrations reached...
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Influence of European beech (Fagus sylvatica) and Norway spruce (Picea abies) on composition of low molecular mass organic acids and on composition of microbial community in forest soils
Zývalová, Jana ; Tejnecký, Václav (advisor) ; Kaštovská, Eva (referee)
Locations of interest for this diploma thesis are located in the Jizera Mountains and represent forest soils developed on acidic rocks (porfyric granite). The sites are tens of meters apart, making sure that all the abiotic conditions affecting the soil-forming process are very similar. The only significant difference between the localities is the species composition of the overstorey vegetation. On one site there is only the European beech (Fagus sylvatica), on the other only the Norway spruce (Picea abies). At both locations, soil samples were taken from each horizon L-B in which basic soil parameters and elemental contents (active and exchangeable soil reactions, moisture, cation exchange capacity, basic saturation, dissolved organic carbon and others) were analyzed. The low molecular mass organic acids were determined by ion-exchange chromatography. The bacterial phyla in the soil were calculated based on the Illumina sequencing to which preceded DNA isolation and quantitative PCR. Based on the results of the analyzes, the monitored soils were characterized as acidic with an unsaturated to strongly unsaturated soil sorption complex. Between the beech and spruce stands, differences in the contents of some water-extractable elements and the exchangeable elements (Ca, K, Mg, Fe, Al) and moisture...
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Distribution of mercury in soils around current and historical sources of mercury emissions
Petlachová, Zuzana ; Navrátil, Tomáš (advisor) ; Tejnecký, Václav (referee)
This thesis provides an overview of mercury distribution in the forest soils located in vicinity of historical and current mercury emission sources. The sites were chosen around Bohemian Karst due to presence of emission source, i.e. iron production processes, cement plants, lime processing plants. The chosen sites were near municipalities of Králův Dvůr, Radotín and Hrádek u Rokycan. From these sites the soils samples were collected from organic and mineral horizons. Average mercury concentration in organic horizons was 288 µg.kg-1, organo-mineral horizons A contained 241 µg.kg-1, anthropogenic horizons M 287 µg.kg-1 and horizons B 56 µg.kg-1 only. The relations among mercury and soil components were tested. Strong link between mercury, soil organic matter (SOM) and sulfur was found. The result indicated that the origin of mercury in soil samples was atmospheric deposition rather than bedrock. High concentrations of oxalate extractable aluminum, iron and manganese in mineral horizons have been explained as the cause of bedrock weathering. Powered by TCPDF (www.tcpdf.org)
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Distribution of selected elements in soils of urban parks in Prague and Brno
Šimeček, Martin ; Mihaljevič, Martin (advisor) ; Tejnecký, Václav (referee)
Prague and Brno belong to one of the most contaminated cities of Czech Republic. The main objective of this study was to compare PGE contents and concentrations of risk elements (Zn, Cd, Pb, Cu, As, Sb, Hg) in the soils of both cities's municipal parks. Soil samples were taken from depths of 0-10 cm, 10-20 cm and 20-30 cm. Besides soil samples, the sand samples from children sandpits were taken from depth 0-30 cm. In 52 samples of soil and sand Pd, Pt and Rh contents were determinated by ICP- MS after Ni-S fire assay procedure. Soil samples were additionally analysed on Pb isotopic composition. Higher PGE contents were determined in Prague; the highest contents were measured at location of Ortenovo náměstí (50,5 μg·kg-1 Pt, 33,9 μg·kg-1 Pd a 11,3 μg·kg-1 Rh). Elevated PGE concentrations were found in the upper layers of most soils in both cities. Elevated contents of risk elements were determined at locations with high traffic density. Most of samples showed that contents of risk elements decrease with depth. The highest concentrations reached Zn (394 mg·kg-1 ), Pb (290 mg·kg-1 ) and Cu (181 mg·kg-1 ). In Prague, the isotopic ratios 206 Pb/207 Pb vary from 1,136 to 1,181; in Brno from 1,161 to 1,192. Measured isotopic ratios suggest contamination both from gasoline and ore combustion. Key words:...
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Composition and activity of microbial community during decomposition of plant litter on two contrasting localities
Burešová, Andrea ; Marečková, Markéta (advisor) ; Tejnecký, Václav (referee)
Decomposition of organic matter in soil is influenced by abiotic and biotic factors and their role is different depending on site, organic substrate and its decomposition phase. Soil microbial community influences soil organic decomposition process in a different way, which is manifested, for example, by changes of microbial abundance and production of extracellular enzymes. The thesis aimed in determining relationship of two main soil microbial decomposers groups - fungi and actinobacteria in decomposition processes in situ. The impact of selected factors on decomposition processes were determined by experiment with litterbags, which were filled with litter of plant with different properties. Astragalus exscapus from the Fabaceae family contains high amounts of nitrogen in the tissues, Fagus sylvatica contains high amounts of carbon and lignin and Carex humilis has less carbon in the tissues than Fagus sylvatica falling in tissue element composition between Astragalus exscapus and Fagus sylvatica. Litterbags with three plant species were put under a litter layer at both contrasting sites. Litterbags and samples of soil were collected every two months during the years 2011-2012. Each litterbag was weighted, DNA was isolated from litter and soil samples and analyses of quantitative real time PCR...
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