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The study of contamination of forested areas of the Czech Republic by mercury
Trávníčková, Gabriela ; Řezáčová, Veronika (referee) ; Komendová, Renata (advisor)
This bachelor thesis deals with the issue of mercury in the environment. It focuses on determining the concentration of total mercury in edible mushrooms and in the soil in 12 localities in the Jeseníky Mountains. A single-purpose absorption spectrometer AMA 254 was used to determine the mercury content. The sites where sampling took place were divided into 6 sites with spruce stand and 6 sites with beech stand. No relationship was found between the type of stand and the amount of accumulated mercury in the mushrooms. On a representative sample of yellow-boletus mushrooms found in each locality, it was found that the higher the amount of mercury in the mushroom, the lower the amount of mercury in the soil. The fungi are therefore able to accumulate mercury from the environment. Thus, they can become a potential source of intoxication when ingested. The mobility of heavy metals in the soils depends on many soil properties (pH, carbon and sulfur content). Metals form more soluble compounds in lower pH environments. The soil pH was very low and the lower the soil pH, the higher mercury concentration in the soil. This fact could be supported by acid fallout. The relationship between the mercury content and the carbon content of the soil confirmed that carbon has the ability to bind mercury. The higher the amount of carbon in the soil, the higher the amount of mercury.
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Sequestration of soil organic matter in broadleaf and coniferous forests in soil at various stages of pedogenesis
Hüblová, Lucie ; Frouz, Jan (advisor) ; Vindušková, Olga (referee)
Soil organic matter (SOM) is an important component of the soil. SOM is responsible for availability of nutrients for plants and soil organisms, formation of soil structure and soils water-holding capacity. SOM is made up of organic matter (OM) of plant and animal origin at various stages of decomposition. SOM can be divided into several components called fractions. Fractions differ between each other in their resistance against decomposition. Main SOM fractions are: (1) free floating particulate organic matter (FPOM) and (2) OM bound to soil mineral surfaces in various ways (MAOM) - OH inside macro- and microaggregates and OM bound to silt and clay surfaces (S+C). It is assumed that MAOM fraction becomes C saturated during soil development and no more C can be sequestered in it. Other fractions, particularly FPOM, that are not dominant C storage in the initial stages of soil development become more important in the later stages and amount of C stored in them increases. However, there is scarcity of studies that examine this assumption. In this work I studied the hypothesis that soils in different stage of development will differ in the amount of C stored in different fractions. On top of that, this difference will be affected by the dominant tree species growing on the soil and the effect of tree...
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Structure and function of microbial communities of montane spruce forest
Štursová, Martina ; Baldrian, Petr (advisor) ; Uhlík, Ondřej (referee) ; Slaninová Kyselková, Martina (referee)
Structure and function of soil microbial communities in montane spruce forest Martina Štursová Abstract Coniferous forests are spatially heterogeneous environments and represent an important ecosystem that acts as carbon sink under current climate storing large amounts of carbon in standing biomass or as soil organic matter. The formation of organic matter via decomposition of dead biomass and transformation of rhizodeposited organic compounds is primarily mediated by microbial community of forest topsoil. Despite growing insight into the composition of these soil communities, little is known about the microbes actually responsible for those transformation processes, about the drivers shaping these communities or their response to increasing numbers of severe disturbances. Studies presented in this thesis contribute to filling the information. The studies were carried out in unmanaged spruce forests in the highest elevations of Bohemian Forest, in both, the undisturbed areas as well as those affected by bark beetle outbreaks at different time periods. Combination of methods including culturing of fungi, enzymatic activity measurements or high throughput sequencing were used to describe the microbial communities, their distribution in space and time, and factors involved in shaping these communities in those...
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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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Molecular biology of soil fungi participating in litter decomposition in forest ecosystems
Voříšková, Jana
In forest ecosystems, substantial part of carbon enters soil in the form of plant litter. The decomposition of litter and soil organic matter represents an important process affecting nutrient cycling and carbon balance in soils. Fungi are considered the primary decomposers in terrestrial ecosystems due to the production of wide range of extracellular enzymes that allow them to attack the lignocellulose matrix in litter. Even if fungi represent key players in organic matter decomposition, the information about the structure and diversity of their communities is still limited and the roles of individual fungal taxa in forest soils remain unclear. This Ph.D. thesis focused on the characterization of fungal communities in forest soils and their potential to decompose plant litter. The method for in-depth analysis of complex microbial communities from environmental samples was established and used. In addition, single eukaryotic functional gene was analysed in soil for the first time at a depth that allowed reliable estimation of diversity. It was demonstrated that microbial community composition differs among horizons of forest soil profile. Despite similar diversity, significant differences in microbial community composition were observed between the DNA and RNA. Several microbial groups highly...
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The study of contamination of forested areas of the Czech Republic by mercury
Trávníčková, Gabriela ; Řezáčová, Veronika (referee) ; Komendová, Renata (advisor)
This bachelor thesis deals with the issue of mercury in the environment. It focuses on determining the concentration of total mercury in edible mushrooms and in the soil in 12 localities in the Jeseníky Mountains. A single-purpose absorption spectrometer AMA 254 was used to determine the mercury content. The sites where sampling took place were divided into 6 sites with spruce stand and 6 sites with beech stand. No relationship was found between the type of stand and the amount of accumulated mercury in the mushrooms. On a representative sample of yellow-boletus mushrooms found in each locality, it was found that the higher the amount of mercury in the mushroom, the lower the amount of mercury in the soil. The fungi are therefore able to accumulate mercury from the environment. Thus, they can become a potential source of intoxication when ingested. The mobility of heavy metals in the soils depends on many soil properties (pH, carbon and sulfur content). Metals form more soluble compounds in lower pH environments. The soil pH was very low and the lower the soil pH, the higher mercury concentration in the soil. This fact could be supported by acid fallout. The relationship between the mercury content and the carbon content of the soil confirmed that carbon has the ability to bind mercury. The higher the amount of carbon in the soil, the higher the amount of mercury.
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Structure and function of microbial communities of montane spruce forest
Štursová, Martina ; Baldrian, Petr (advisor) ; Uhlík, Ondřej (referee) ; Slaninová Kyselková, Martina (referee)
Structure and function of soil microbial communities in montane spruce forest Martina Štursová Abstract Coniferous forests are spatially heterogeneous environments and represent an important ecosystem that acts as carbon sink under current climate storing large amounts of carbon in standing biomass or as soil organic matter. The formation of organic matter via decomposition of dead biomass and transformation of rhizodeposited organic compounds is primarily mediated by microbial community of forest topsoil. Despite growing insight into the composition of these soil communities, little is known about the microbes actually responsible for those transformation processes, about the drivers shaping these communities or their response to increasing numbers of severe disturbances. Studies presented in this thesis contribute to filling the information. The studies were carried out in unmanaged spruce forests in the highest elevations of Bohemian Forest, in both, the undisturbed areas as well as those affected by bark beetle outbreaks at different time periods. Combination of methods including culturing of fungi, enzymatic activity measurements or high throughput sequencing were used to describe the microbial communities, their distribution in space and time, and factors involved in shaping these communities in those...
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Status of soil organic carbon and changes in soil organic matter in Novohradsko
BOROVKA, Jan
The aim of the diploma thesis was to evaluate the content of soil organic carbon in the area of Novohradsko. Soil organic carbon was monitored in its stable (SOC) and labile (WSOC) form, followed by the total organic carbon stock (Cpool). These soil parameters were determined in soils of different land cover types (forest, arable land, grassland) in the area formed by the catchments of Pasecký, Bedřichovský, Váčkový and Veverský stream. Data obtained in 2001, 2007 and 2014 were statistically analysed and the comparison of the data from different catchments was conducted. The results show the impact of different land use on the amount of soil organic carbon. In general, a higher amount of soil organic carbon were found in soils of grassland and forest soils, whereas a lower amounts were found in arable land. The comparison and the time development analysis show that there is a trend of the increase in quantity of stable fraction of soil organic carbon in all categories of land cover over the whole monitored period. The opposite trend of a continuous decrease over the whole of the monitored period in all categories of land cover was observed in amounts of labile fraction of soil organic carbon. It can be said that there is an increase in the stock of a stable fraction of soil organic carbon due to lower losses of the labile fraction of soil organic carbon in forest soils, arable soils and soils of grassland.
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Combination of biochemical and high-throughput-sequencing approaches to study the role of Antinobacteria and fungi in the decomposition of plant biomass
Větrovský, Tomáš ; Baldrian, Petr (advisor) ; Slaninová Kyselková, Martina (referee) ; Tomšovský, Michal (referee)
Dead plant biomass is a key pool of carbon in terrestrial ecosystems. Its decomposition in soil environments is thus an essential process of the carbon cycle. Fungi are considered to be the primary decomposers in soil ecosystems because of their physiological adaptations and enzymatic apparatus composed from highly effective oxidative and hydrolytic enzymes. Many recent works show that in addition to fungi, bacteria may also play a significant role in lignocellulose decomposition and among bacteria, the members of the phylum Actinobacteria are often regarded to significantly contribute to cellulose and lignocellulose decomposition. This thesis is focused on the evaluation of the role that fungi and Actinobacteria play in dead plant biomass degradation. First, it explored mechanisms involved in degradation, in particular the enzymatic breakdown of major lignocellulose components as cellulose, hemicelluloses and lignin. Enzymatic apparatus of the saprotrophic fungus Fomes fomentarius was explored both in vitro as well as in vivo. Several Actinobacteria were isolated from soil and comparative experiments, investigating production of hydrolytic enzymes, were carried out to track the transformation of polysaccharides and lignin by these strains. To explain the roles of lignocellulose decomposers in...
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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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