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Anomalous occurrences of arsenic in soils of the Czech Republic
Svoboda, Ondřej ; Drahota, Petr (advisor) ; Hojdová, Marie (referee)
This thesis aims to evaluate the anomalous concentrations of arsenic in soils (>30 mg/kg) of the Czech Republic. Anomalous concentrations are mainly caused by combustion of fossil fuels, mining operations and weathering of arsenic-rich rocks. The largest part of contaminated soil in CR is related to the combustion of arsenic-rich lignite, and includes, e.g., the area of Ore Mountains. The highest concentrations of arsenic in soil of CR are up to thousands of mg/kg. For example, soil adjacent to the Kutná Hora ore district contained up to 6 890 mg/kg of As. Such a high concentrations are due to mining operations. Beside anthropogenic sources, weathering of arsenic-rich rocks at Mokrsko has resulted in anomalous concentrations in soil that may attain up to 2 890 mg/kg.
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Mercury emissions from anthropogenic sources
Podolský, Filip ; Ettler, Vojtěch (advisor) ; Hojdová, Marie (referee)
This bachelor thesis is focused on mercury fluxes in the environment wit the emphasis on the industrial pollution. Based on general information about mercury and characteristics of it's compounds, occurrence in the atmosphere, hydrosphere and pedosphere mercury fluxes and behaviour of mercury in the global biogeochemical cycle are described. The main topic of this thesis is to overview all sectors, which are the main contributors to the global mercury pollution. The largest producers of the Hg emissions are coal-fired power plants, artisanal small-scale mining and the mining/production of non-ferrous metals. Conclusions are dedicated to comparisons of natural and anthropogenic emissions of Hg in the present and in pre-industrial times.
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Tree rings dendrochemistry near Cu smelter
Jarošíková, Alice ; Mihaljevič, Martin (advisor) ; Hojdová, Marie (referee)
Nkana smelter belonged to the main sources of contamination by trace elements (especially Cu and Co) in the area of African city Kitwe (Copperbelt, Zambia). The main objective of this study was to compare elemental and isotopic composition of Zambian soils and tree rings, and to investigate biogeochemical processes between plants and soils in contaminated and uncontaminated environment. Elemental composition (Cu, Co, Cr, Mn, Fe, Zn, Pb, Cd, Hg and Tl) and isotopic composition of Cu (63 Cu/65 Cu) were determined in soils and tree rings of pine trees (Pinus latteri, Pinus kesiya) using ICP-MS , AMA and MC ICP-MS. Our results demonstrated that soils and tree rings were both affected by mining and metallurgical activity. Increasing content of elements with depth is the result of the mobility of the elements in uncontaminated soil profile. Soil from contaminated site had the highest metal contents especially in the upper part of the soil profile as a result of continuous contribution of metallurgical components during long-term smelter operation. Fractionations of Cu isotopes in soils were caused primarily by interactions with plants. Concentration changes that some elements showed in the individual tree rings could be the effect of variable intensity of pollution in the area. In the case of Cu, however,...
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Freshwater wetlands as a biogeochemical archive: Temporal changes in climate and environmental records
Zemanová, Leona ; Novák, Martin (advisor) ; Mihaljevič, Martin (referee) ; Hojdová, Marie (referee)
Worldwide, peatlands cover an area of 4.106 km2 . Plant primary production dominated over organic matter decomposition and enabled organic matter to accumulate during the last 11 000 years. Peatlands represent a reservoir of atmospheric carbon and they are a useful scientific tool for reconstructions of historical atmospheric pollution. The first part of the thesis focuses on peatlands as a dynamic carbon reservoir under predicted climate change that would influence carbon cycling and emissions of greenhouse gases into the atmosphere. Three methodological approaches were used - a mesocosm laboratory incubation, a transplant experiment and in situ gas flux measurements. The laboratory incubation studied the response of peat samples from temperate (Velké Dářko, Czech Republic) and boreal (Stor Åmyran, Sweden) zone to a temperature increase, water table decrease and their combination. Today, the warmer site exhibits ~14 times higher CH4 production potential than the colder site (28 mg m-2 hr-1 at VD, and 2 mg m-2 hr-1 at SA). Both sites respond differently to temperature increases. Changes in methane production were up to 9 fold due to different temperatures. A gradual decrease of water table level from 2 to 14 cm below the peat surface had a much stronger effect, VD exhibited a decrease in methane...
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Mercury in soils from mining and smelting districts in Zambia and Namibia
Podolský, Filip ; Ettler, Vojtěch (advisor) ; Hojdová, Marie (referee)
This master thesis is a part of project IGCP No. 594: "Assessment of Impact of Mining and Mineral Processing on the Environment and Human Health in Africa" and its goal is to determine and compare mercury content in 91 soil samples from mining and smelting areas in northern Namibia and 68 soil samples from the Copperbelt province in Zambia. Highest mercury concentrations in soils (with maximum 4.39 mg Hg kg-1 ) were found near the Tsumeb copper smelter in Namibia, whereas Hg concentrations were significantly lower in the Zambian Copperbelt (up to 0.392 mg Hg kg-1 ). Decreasing concentration of contamination corresponding to distance from the source of pollution has been confirmed at both localities. For an estimation of a possible source of contamination, 26 samples from smelting processes and waste were also taken. Highest concentrations of Hg were observed in Tsumeb again (219 mg Hg kg-1 in bag- house residue and 3,5 mg Hg kg-1 in processing wastes on tailing dams). Studies of mercury mobility in soil profile by correlation coefficients has shown Hg dependent on the content of sulfur and organic carbon, which indicates a dependence on the content of organic matter. Among metals and metalloids best correlations between Hg and Cu, As, Sb, Pb, and Zn were calculated. Because mercury is currently...
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Tree rings dendrochemistry near Cu smelter
Jarošíková, Alice ; Mihaljevič, Martin (advisor) ; Hojdová, Marie (referee)
Nkana smelter belonged to the main sources of contamination by trace elements (especially Cu and Co) in the area of African city Kitwe (Copperbelt, Zambia). The main objective of this study was to compare elemental and isotopic composition of Zambian soils and tree rings, and to investigate biogeochemical processes between plants and soils in contaminated and uncontaminated environment. Elemental composition (Cu, Co, Cr, Mn, Fe, Zn, Pb, Cd, Hg and Tl) and isotopic composition of Cu (63 Cu/65 Cu) were determined in soils and tree rings of pine trees (Pinus latteri, Pinus kesiya) using ICP-MS , AMA and MC ICP-MS. Our results demonstrated that soils and tree rings were both affected by mining and metallurgical activity. Increasing content of elements with depth is the result of the mobility of the elements in uncontaminated soil profile. Soil from contaminated site had the highest metal contents especially in the upper part of the soil profile as a result of continuous contribution of metallurgical components during long-term smelter operation. Fractionations of Cu isotopes in soils were caused primarily by interactions with plants. Concentration changes that some elements showed in the individual tree rings could be the effect of variable intensity of pollution in the area. In the case of Cu, however,...
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Freshwater wetlands as a biogeochemical archive: Temporal changes in climate and environmental records
Zemanová, Leona ; Novák, Martin (advisor) ; Mihaljevič, Martin (referee) ; Hojdová, Marie (referee)
Worldwide, peatlands cover an area of 4.106 km2 . Plant primary production dominated over organic matter decomposition and enabled organic matter to accumulate during the last 11 000 years. Peatlands represent a reservoir of atmospheric carbon and they are a useful scientific tool for reconstructions of historical atmospheric pollution. The first part of the thesis focuses on peatlands as a dynamic carbon reservoir under predicted climate change that would influence carbon cycling and emissions of greenhouse gases into the atmosphere. Three methodological approaches were used - a mesocosm laboratory incubation, a transplant experiment and in situ gas flux measurements. The laboratory incubation studied the response of peat samples from temperate (Velké Dářko, Czech Republic) and boreal (Stor Åmyran, Sweden) zone to a temperature increase, water table decrease and their combination. Today, the warmer site exhibits ~14 times higher CH4 production potential than the colder site (28 mg m-2 hr-1 at VD, and 2 mg m-2 hr-1 at SA). Both sites respond differently to temperature increases. Changes in methane production were up to 9 fold due to different temperatures. A gradual decrease of water table level from 2 to 14 cm below the peat surface had a much stronger effect, VD exhibited a decrease in methane...
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Mercury emissions from anthropogenic sources
Podolský, Filip ; Ettler, Vojtěch (advisor) ; Hojdová, Marie (referee)
This bachelor thesis is focused on mercury fluxes in the environment wit the emphasis on the industrial pollution. Based on general information about mercury and characteristics of it's compounds, occurrence in the atmosphere, hydrosphere and pedosphere mercury fluxes and behaviour of mercury in the global biogeochemical cycle are described. The main topic of this thesis is to overview all sectors, which are the main contributors to the global mercury pollution. The largest producers of the Hg emissions are coal-fired power plants, artisanal small-scale mining and the mining/production of non-ferrous metals. Conclusions are dedicated to comparisons of natural and anthropogenic emissions of Hg in the present and in pre-industrial times.
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Anomalous occurrences of arsenic in soils of the Czech Republic
Svoboda, Ondřej ; Drahota, Petr (advisor) ; Hojdová, Marie (referee)
This thesis aims to evaluate the anomalous concentrations of arsenic in soils (>30 mg/kg) of the Czech Republic. Anomalous concentrations are mainly caused by combustion of fossil fuels, mining operations and weathering of arsenic-rich rocks. The largest part of contaminated soil in CR is related to the combustion of arsenic-rich lignite, and includes, e.g., the area of Ore Mountains. The highest concentrations of arsenic in soil of CR are up to thousands of mg/kg. For example, soil adjacent to the Kutná Hora ore district contained up to 6 890 mg/kg of As. Such a high concentrations are due to mining operations. Beside anthropogenic sources, weathering of arsenic-rich rocks at Mokrsko has resulted in anomalous concentrations in soil that may attain up to 2 890 mg/kg.
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