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Microbial mobilization of arsenic from soil at the Mokrsko gold deposit
Redlich, Aleš ; Drahota, Petr (advisor) ; Száková, Jiřina (referee)
The Mokrsko gold deposit is characterised by high arsenic concentrations in regolith. Naturally contaminated regolith and stream sediment samples have been studied in order to determine microbially mediated processes that lead to As mobilization. Arsenic concentration in regolith and sediment were 905 mg kg-1 and 1749 mg kg-1 , respectively. The mineralogy of arsenic in the regolith is dominated by arsenic-bearing goethite and minor arseniosiderite and Ba-pharmacosiderite. In contrast, highly reducing sediments are mainly characterised by secondary realgar and less arsenic-bearing goethite and secondary arsenates. These samples were used for incubation experiments under both aerobic and anaerobic conditions. When glucose was supplied as a C source under anaerobic conditions, indigenous bacteria significantly enhanced the extent of As release from the solid samples into solution. Highly positive correlation between the extracted amount of As and Fe implied that the microbial dissolution of Fe(III)-oxides is responsible for the As release, with possible contribution of secondary arsenates dissolution. On the other side, small amount of arsenic was released from the sediment during the aerobic incubation through the microbially mediated oxidation of secondary realgar. In attempt to find some bacterial...
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Speciation analysis of toxicologocally important forms of arsenic: development and comparison of hydride generation based methods with ICP-MS detection
Trojánková, Nikola ; Matoušek, Tomáš (advisor) ; Száková, Jiřina (referee)
Nowadays, arsenic is becoming an important pollutant in the environment. Chronic exposure to arsenic can cause number of serious diseases. Therefore, a development of analytical methods for trace and ultratrace speciation analysis- analysis of individual forms or phases in which As is found in the sample - is fully in place. This Thesis compares four methods of trace speciation analysis, with focus on limits of detection and quantification, and on comparison of results of analysis of river and sea water reference materials. Methods based on hydride generation with preconcentration by cryotrapping and AAS or ICP-MS detection, with limits of detection in ng or tenths of ng·dm-3 , are compared with procedures employing HPLC, with ICP-MS detection. The Thesis includes development and optimization of a pre-reduction step of postcolumn hydride generation with on-line pre-reduction of pentavalent arsenic species, in order to improve sensitivity of this method. Limits of detection around 10 ng·dm-3 are achieved. The results of analyses obtained by individual methods are in excellent agreement. Keywords: Arsenic, speciation analysis, hydride generation, atomic absorption spectrometry, inductively coupled plasma- mass spectrometry, high efficiency liquid chromatography, limits of detection.
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Determination of mercury content in materials in various stages of wine production, geochemistry of mercury in the vineyard
Buchtová, Jana ; Mihaljevič, Martin (advisor) ; Száková, Jiřina (referee)
This work was focused on determination of mobility of mercury and its content in materials from each part of the wine production process. The aim of this work was to establish the most suitable analytical method for determination and evaluation of changes in content of mercury during the production process. Samples of soil, biomass, vine wood, vine leaves, berries, grapes, rough wine and cider sediment of red wine and also four liquid samples of white wine were analyzed. All the samples originated from the area of Malé Žernoseky and Rudoltice nad Bílinou, white wine samples were collected in Chrámce u Mostu in the northern part of the Czech Republic. Analyzer AMA 254 was used for determination of mercury in solid samples and liquid samples had to be prearranged by PSA analyzer. This analytical approach was not so sufficient and mercury from liquid samples had to be captured by gold-coated amalgamator in first step and then analyzed by AMA 254. Obtained results confirmed interception of mercury mostly in leaves and in the grapes peelings. The grapes from Rudoltice contained 0,0022 mg/kg in dry mass and further processed wine grapes contained 0,0068 mg/kg in dry mass. The lowest content of mercury was in cider and completed wine contained less mercury then the rough wine. Unfiltrated cider from Chrámce has...
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Geochemical model of arsenic at the Mokrsko gold deposit
Drahota, Petr ; Pertold, Zdeněk (advisor) ; Száková, Jiřina (referee) ; Zeman, Josef (referee)
Geochemical model of arsenic at the Mokrsko gold deposit Dissertation of Petr Drahota 1 Abstract The dissertation contributes to the As mobility at the naturally contaminated site of Mokrsko gold deposit in Central Czech Republic. The primary goal of the dissertation is to fill some gaps in previous research carried out at the study site in order to contribute to the quantitative biogeochemical model of As in the bedrock-groundwater-soil-surface water system. In the first part, the previous research related to As environmental issues at the study site has been reviewed, discussed and evaluated. These include detail information on (i) the extent of natural As contamination in bedrock and soil, (ii) the extent of As contamination in groundwater, (iii) the primary and secondary As mineralogy in bedrock and soil, (iv) the chemical speciation of As in soil and (v) the leaching experiments of the gold ore. In the second part, the mineralogical and chemical speciation of As in soil, in stream and fishpond sediments and dissolved As concentrations in waters have been studied to determine the processes that lead to release of As into solution and control its concentration under different redox conditions at the Mokrsko gold deposit. The highest dissolved As was found in groundwater (more than 1000 g L-1 ), which...
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Total contents and speciation of arsenic and selenium in plants growing in soils with different physico-chemical properties
Tremlová, Jana ; Száková, Jiřina (advisor) ; Vymazal, Jan (referee)
This dissertation thesis deals with uptake, accumulation and transformation of arsenic and selenium in plants growing on soils with different chemico-physical soil properties. The contents of arsenic were investigated in 99 wild plant species, coming from 27 different families and 6 different vegetables growing in arsenic contaminated soils. The results suggest that there are species-specific mechanisms which protects certain plants from the excessive uptake of arsenic from the soil. On the other hand, there are plants using a strategy of accumulation, which theoretically may increase the risk of arsenic entry into the food chain, whether through grazing cattle and wildlife or through consumption of vegetables growing on arsenic contaminated soils. The most prevalent arsenic compounds are AsV and AsIII. Other arsenic compounds occure as minor species. An important finding was detection of arsenobetaine in Plantago lanceolata L. and Carex praecox Schreb ..
The contents of selenium were examined in 73 species of wild plants, coming from 29 different families. The results suggest that naturally low levels of selenium in the soil of selected locations along with a low capability of selenium uptake via collected plant species lead to the low content of selenium in plant biomass which may contribute to selenium deficient throughout the food chain. Foliar application of selenate on wild plant communities and on some types of vegetables in our case Brassica oleracea var. italica can have a positive impact on increasing the selenium content in the aboveground biomass of these plants and by extension, increase the selenium content in the human diet. Dominant selenium compounds in the aboveground biomass of the analyzed plants were SeVI and selenomethionine, with variable proportion of other commonly occurring organic selenium compounds, which is mainly affected by plant species.
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The contamintation level of sediments from water reservoir Orlík by organic and inorganic pollutants
Dvořák, Tomáš ; Száková, Jiřina (advisor) ; Vymazal, Jan (referee)
Due to sorption processes, sediments can retain a wide range of toxic substances, which are transported together with the sediment over long distances from the place of their origin. Dam reservoirs are significant sinks of such sediments and they can be indicative of the overall burden level in surface water of the basin. This thesis works with the assumption that sediments of a valley reservoir can help to estimate the sources and extent of water pollution in the area of interest.
The aim of this thesis was to assess i) the level of contamination of bottom sediments in the Orlík reservoir with organic and inorganic pollutants, and ii) the potential impact of individual tributaries on the overall level of contamination of the sediments. In the literature review, the current level of knowledge in the topic of the total contents and speciation of toxic elements and specificities of the behavior of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) in water, sediments and aquatic organisms was evaluated. The biological activity and eutrophication potential of sediments were discussed, as well.
A total of 34 composite samples of bottom sediment collected in different parts of the Orlík reservoir and its major tributaries were evaluated. Bioavailability of major pollutants was also observed in individual tributaries based on their content in the tissues of mollusks.
Atomic spectrometry revealed increased concentrations of As, Cd and Zn in sediments of the Orlík reservoir. Arsenic concentration limits were significantly exceeded at the bottom part of the reservoir from the confluence of the Otava and Vltava rivers toward the body of the dam. Higher level of cadmium and zinc were detected in sediments of the Otava River. The analysis of tissues of bivalves in tributary areas confirmed significant bioaccumulation ability of cadmium. Among others, significant dependence of phosphorus level on the total content of iron and aluminum in sediments was detected.
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Risk element sorption on waste materials from olive oil production
Hovorka, Miloš ; Száková, Jiřina (advisor) ; Trakal, Lukáš (referee)
The main objective of this thesis is to verify the efficiency of waste material from olive oil production to immobilize risk elements Pb, Cd and Zn in extremely contaminated soil and to verify following hypothesis: application of waste material from olive oil production will limit the availability of risk elements in the soil and also improves a supply of soil available nutrients and biological properties of the soil. The work is divided into two parts, theoretical part (literature review) and experimental part.
The theoretical part contains a general description of the risk elements and their possible harmful effects on living organisms, indicating their possible sources of entry into the environment, describes the behavior of these elements in the soil, especially events that contributes to the retention of soil. Furthermore, there are some possible methods for remediation of soil contaminated with hazardous elements and is described in more detail immobilization technique using soil improvers. In this chapter is devoted to the waste material from olive oil production, whose properties are tested in the experimental part of this work.
The experimental part is focused on verification sorption capability of waste material from olive oil production for selected risk elements. As a waste material has been used dry olive residue (known as DOR), and DOR after remediation of these types of fungi: Penicillium chrysogenum, Coriolopsis floccosa, Bjerkandela adusta and Chondrostereum purpureum. Analytical methods were used to determine the concentrations of the elements, the pH, the point of zero charge (pHpzc), and cation exchange capacity (CEC) for the individual samples representing material DOR and DOR after remediation of certain species of fungi. The preliminary sorption experiment determined sorption efficiency for the elements Cd, Pb and Zn for all the material tested. Stability of the risk element bonds was verified via model desorption experiment. Model laboratory incubation experiment was carried out to assess the potential changes of hazardous elements mobility in the contaminated soil, depending on dose and type of DOR material. At the same time there were determined contents of available proportions of essential elements in the soil. The contents of elements were determined by atomic spectrometry (ICP-OES) and the results analyzed by adequate statistical methods.
Results showed good sorption capacity of the waste material DOR, especially after transformation with different species of fungi, for hazardous elements and particularly Pb, less then Cd and Zn. The desorption experiment, however, showed unstable linkages elements in samples DOR, particularly in the case of Zn, which is also reflected in the incubation experiment. This instability is probably due to the low pH material DOR, therefore it would be useful for further research take into account the increase of pH levels of these samples. In terms of elemental composition appears to be biotransformed DOR as a good source of nutrients. The treatment of thesoil increased accessibility of nutrients such as Cu, Fe and Mn for plants.
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The risk element contents in soil and vegetation cover at selected locations within Hradec Králové city
Bartošová, Tereza ; Száková, Jiřina (advisor) ; Hejtmánková, Alena (referee)
The county town named Hradec Králové is located in eastern Bohemia on the confluence of Elbe and Orlice rivers. It is situated in a flat area, with many green areas and the absence of heavy industry. The industrial activity is concentrated in small business - engineering, chemical, electrical and food processing industries. All these aspects of human activity may be associated with risk elements contamination of the environment. The town is characterised by the high traffic density; we can therefore also assume the presence of risk elements in the air and subsequently soil contamination in the proximity of these roads. The aim of the study was to analyze the level of contamination of soil and vegetation in the city caused by risk elements (As, Be, Cd, Co, Cr, Cu, Mo, Ni, Pb, V and Zn). According to sampling scheme, which involved 86 sampling points, there were taken samples of soils and aboveground parts selected plant species: dandelion (Taraxacum sect. Ruderalia) and doorweed (Polygonum aviculare) occurring at all the sampling points. These samples were analysed for the risk elements contents.
In most of cases the risk element levels did not exceed the maximum allowable limits for the content of elements in soil and plants given by Decree no. 13/1994 Coll. and Directive no. 2002/32/EC. In the case of soil, there were significantly higher values of potentially mobilizable contents measured for arsenic. But this was not reflected on the contents of this element in the vegetation when all results were below the detection limit of the analytical method. Rarely, the values exceeding the limits were observed in several soil samples in the case of lead and cadmium. While for lead no increased concentrations of this element in the vegetation was observed, the cadmium levels occurring in dandelion exceeded in several cases the limits for fodder crops. The ability of doorweed to accumulate the risk elements was lower compared to dandelion.
Linear regression analysis showed that there is no significant relationship between the element contents in the soil and vegetation and the distance from the road. It therefore appears that the contents of elements in the soil and vegetation are not affected by traffic. Due to the significant positive correlation of most elements (except Cd and Zn) in the soil can be estimated that the levels in the soil are given rather by the character of the subsoil. This speculation but would require more detailed geological and geochemical survey of the site.
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The contents of selected persistent organic pollutants in soils at selected locations within Hradec Králové city
Bartošová, Barbora ; Száková, Jiřina (advisor) ; Radim, Radim (referee)
Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous contaminants entering the environment from both natural and anthropogenic sources. The main anthropogenic sources are processes for the production of electricity and thermal energy, waste incineration, road traffic and motor vehicles, aircraft, boats, steam and diesel-electric locomotives and some industrial technologies. Besides these main sources there are still a number of others, less important, e.g. working with hot tar, asphalt pavement wear and tire during vehicle operation, coking plants, plants for processing of oil and some metals plants. An indispensable source in the cities as domestic solid fuel burning furnaces.
Although Hradec Králové do not belong to the cities with extreme levels of contaminants in the air, according to the Czech Hydrometeorological Institute, the levels of benzo(a)pyrene in the case of annual average concentrations exceeding the maximum allowable concentrations occurred here in 2013. While air quality is monitored regularly, the PAHs contents in soils and vegetation are not so. In our simple single experiment, we decided to assess the level of contamination of soil PAHs in the land of Hradec Kralove. It was collected 86 soil samples, in which were determined contents of 16 PAHs. Further, mushroom fruit samples that were found in the individual sampling points were analyzed.
The results showed large variability of PAHs content in the city, but did not indicate significant levels of contamination. The sum of all the determined PAU does not exceed the permissible value of the contents of these elements in soils. However, in several cases exceeding the maximum allowable content in soils with different PAHs, especially fluoranthene, anthracene and chrysene. Linear correlation analysis showed that the levels of all monitored PAHs are close correlations, which indicates that the entire spectre of PAHs in this case always originates from the same source. The PAH contents in mushrooms were in most cases below the detection limit of the determination, only rarely the detectable contents of individual PAHs were found (Cylocybe gambosa, Agaricus arvensis). We can speculate about the limited ability of fungi to accumulate PAHs or their ability to degrade these substances.
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