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Wood ants of genus Formica as important ecosystem engeneers
Jílková, Veronika ; Frouz, Jan (advisor) ; Tajovský, Karel (referee) ; Bonkowski, Michael (referee)
This thesis consists of one chapter accepted for publication in a book and four papers published in international journals with impact factors. All of the contributions deal with the role of wood ants in energy and nutrient fluxes in forest ecosystems. Wood ant nests are known as hot spots of carbon dioxide (CO2) production and are also thought to affect methane (CH4) flux. Stable high temperatures are maintained in ant nests even in cold environments. This study is focused on quantification of CO2 and CH4 flux in wood ant nests, contribution of ants and microbes to CO2 production, properties of nest material that affect CO2 production and the role of ants and microbes in the maintenance of nest temperature. The research was conducted in temperate and boreal forests inhabited by wood ants (Formica s. str.). Gas fluxes were measured either by an infrared gas analyser or a static chamber technique. Ants and nest materials were also incubated in a laboratory. Material properties potentially influencing CO2 flux, such as moisture, nutrient content or temperature were determined. According to the results, CH4 oxidation was lower in wood ant nests than in the surrounding forest soil suggesting that some characteristics of ant nests hinder CH4 oxidation or promote CH4 production. Wood ant nests clearly are hot...
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The development of the birth rate and preschool education in the Czech Republic after 1950
Křesťanová, Jana ; Rychtaříková, Jitka (advisor) ; Kocourková, Jiřina (referee)
The development of the birth rate and preschool education in the Czech Republic after 1950 Abstract The main aim of the thesis is to map in detail the development of preschool education and financial support for families with children in the Czech Republic in the context of the development of birth rate after 1950. The development of birth rate in the thesis is not only analyzed by using basic indicators, but also through deeper decomposition methods. It turns out, that quality and availability of all network preschool institutions in the context has a certain role in the birth rate. The reconciliation of work and family is very important for lots of parents and sufficient offer of preschool care can help it. However, the demand for preschool institutions exceeded supply, as was shown in accordance with obtained data. It was also found out by the insight into the outcomes of surveys that the vast majority of respondents do not think that a preschool child of working mother would be suffering. In the future, should not only expand the capacity of childcare facilities as well as other options for facilitation of reconciling work and family life, such as better offer of flexible working hours. Keywords: birth rate, decomposition, preschool facilities, financial support for families with children, surveys,...
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Comparison of mortality trends in Central Europe and Baltic countries from 1970 to the present
Horník, Vojtěch ; Hulíková Tesárková, Klára (advisor) ; Burcin, Boris (referee)
Comparison of mortality trends in Central Europe and Baltic countries from 1970 to the present Abstract The aim of this thesis is to assess the most important mortality trends development in countries of Central Europe and Baltic region between 1970 and 2009. The measures used involve life expectancy at birth and life expectancy at the age of 65; besides of this, the age-specific contributions to life expectancy changes are computed according to the method of R. Pressat. The convergence and divergence tendencies among the analyzed countries and between the two regions are evaluated in this thesis as well. Main findings are, on one hand, that mortality trends are relatively similar within each of the regions. When comparing regions between each other, however, significant differences, mostly in the period between mid-1980s and mid-1990s, arise, they are attributed mostly to the influence of mortality crisis in Baltic region after the Soviet Union dissolution. Even though after 1994 mortality development was favourable in Baltic countries, they did not reach mortality level of Central Europe until 2009. Keywords: mortality, Central Europe, Baltic countries, life expectancy, decomposition, convergence, divergence
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Vegetation of post-mining sites determines soil microbial community structure and soil processes
Urbanová, Michaela ; Baldrian, Petr (advisor) ; Bárta, Jiří (referee) ; Chroňáková, Alica (referee)
Vegetation of post-mining sites determines soil microbial community structure and soil processes Mgr. Michaela Urbanová Abstract The aim of this thesis, which consists of four published articles, was to investigate the effect of vegetation on soil microbial communities and processes in de novo developing soil substrate on the brown-coal spoil heaps in the surrounding of city Sokolov. Spoil material - soil clayey substrate, which had been gradually mined from the opencast brown coal mine, stratified onto spoil heaps and reclaimed by assisted afforestation with selected tree species or left for spontaneous plant succession, changes its biotic and abiotic characteristic in the course of time and particularly under the influence of plants. Changes of spoil substrate characteristics are related to the growth of plant roots and particularly also to the production of plant biomass, which is decomposed gradually and takes part of soil, where participates to soil organic matter. The process of plant dead materials decomposition and transformation is the function of the activity of soil organisms and among them notably soil microorganisms. Moreover, the presence of many of them is closely related to the presence of vegetation, whose symbionts or pathogens are. The exact mechanisms of the plant-microbes interactions...
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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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Determination of selected elements in plant materials using atomic spectrometry
Rylova, Kristina ; Hraníček, Jakub (advisor) ; Rychlovský, Petr (referee)
The aim of this bachelor thesis was to determine the elements Se, Zn, Ca and Mg in plant samples using atomic absorption spectrometry with two different types of atomization. The both methods has been optimized for the determination of these elements. Optimization of a burner height which generally ranged between 6.0 and 7.0 cm and optimization of the flow rate of acetylene, air and nitrous oxide was needed for the method using flame atomization. It also has been set location of the hollow cathode lamp. Optimization of dilution of hydrochloric acid, the concentration of sodium borohydride and the flow rate of the sample was needed for the method of atomic absorption spectrometry with the chemical generation of volatile hydrides. Optimal conditions, which were found, were used for measurement method performance which are describe the method for the determination of individual elements. The limit of detection for selenium was 0,496 µg L-1, for zinc was 6,01 µg L-1, for calcium was 15,51 µg L-1 and for magnesium was 2,47 µg L-1. Optimal conditions were also used for determination of the elements in real samples which were prepared by decomposition of plant materials with nitric acid in a microwave oven. Samples were diluted to provide a measurable response and the auxiliary solution of potassium...
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The influence of the dominant trees and grain substrate the composition of the microbial community studied by PLFA
Stachová, Sandra ; Frouz, Jan (advisor) ; Heděnec, Petr (referee)
The aim of the thesis was to analyze soil microbial communities of three ecologically different locations, about 25 years old, forestry reclaimed dumps in the Republic of Poland, namely dumps of brown coal mine Bełchatów and sand mines Piaseczno and Szczakowa. I evaluated the degree of dependence of structure and composition of these communities on various substrate grain sizes and the influence of the dominant tree species. These were stands of birch (Betula pendula), pine (Pinus silvestris), oak (Quercus robur) and alder (Alnus glutinosa). Analysis of soil microbial communities was made by evaluating specific phospholipid fatty acids (PLFA) of microorganisms. It is the most appropriate way to implement the relatively rapid analysis of large numbers of samples, since PLFA are easily extractable and act as biomarkers indicating the presence of a number of different microorganisms (fungi, G- and G + bacteria, Actinobacteria, etc.) and thus allowing a qualitative and quantitative assessment of whole microbial communities. PLFA analysis enables to detect a total concentration of PLFA only in living soil microbial biomass. I analyzed 66 soil samples, 33 from an Oe layer and 33 from an A layer, every in three replications, i.e. three replications were collected at each location below each tree...
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Nonmarital and marital fertility in the Czech Republic and from international perspective. Trends, patterns and attitudes
Srnová, Zdeňka ; Rychtaříková, Jitka (advisor) ; Kraus, Jaroslav (referee)
Nonmarital and marital fertility in the Czech Republic and from international perspective. Trends, patterns and attitudes. Abstract The aim of this master thesis is to describe the development trends of marital and nonmarital fertility in the Czech Republic and to analyze selected indicators of fertility. As tools are used to certain methods of demographic analysis. The first part addressis the basic concepts related to the issue of marital and nonmarital fertility, data sources and a description of the historical development of nonmartial fertility. The analytical part include basic analysis of fertility by age, marital status, education, birth order and the decomposition of the total fertility rate and proportion of childern born outsider marriage in the Czech Republic and Austria too. Keywords: marital fertility, nonmarital fertility, decomposition, total fertility rate, value orientation
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Fungi associated with decomposing wood in temperate forests
Štercová, Lucie ; Baldrian, Petr (advisor) ; Zikánová, Blanka (referee)
Wood decaying fungi are an essential part of all forest ecosystems. On their functioning depends a number of other organisms which use substances produced during decay of wood. Enzymes that degrade wood represent indispensable tool for fungi in converting structural compounds of wood to water and carbon dioxide. That makes them an essential part of the carbon cycle in nature. The dynamic of fungal communities on decaying wood is determined by a range of abiotic and biotic factors. The variability of microclimatic conditions, differences in the wood humidity and a gaseous mode are identifying stress factors which define the presence of species adapted to those conditions. An important factor, with which we can partially predict community composition, is the degree of decomposition of wood and the history of a species on the substrate. Another indicator, which may partly explain the composition of the community is a way of dying of a tree and a type of decaying substrate. Often, the development of a community follows from the primary colonizers, with high tolerance to unfavorable conditions, through the secondary colonizers, which have the ability to obtain the substrate over primary colonizers, but require more stable microclimatic conditions, to late colonizers, who are adapted to stress factors as...
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Impact of litter quality on decomposition
Vicena, Jakub ; Frouz, Jan (advisor) ; Cajthaml, Tomáš (referee)
The text of the thesis is divided into two parts. The literature overview discusses the importance of decomposition to carbon cycling in soils and evaluation of biological, physical and chemical factors that affect decomposition. To understand the factors affecting the soil respiration is essential to improve the global carbon balance. Decomposition affects also the release of nutrients, soil fertility and other soil processes and properties. The very project aims at the impact of leaf litter quality assessment (specifically, the C: N: P ratio) on the rate of decomposition. The assumption is that the low C:N ratio initially accelerates the decomposition which quickly reaches its minimum. Conversely, at a high C: N ratio the rate of decomposition is initially slower and subsequently reaches its minimum, and the average value of decomposition will be higher than in samples with low C:N ratio. For litter which has undergone leaching phase none of the significant differences in respiration of the individual samples with different C:N were statistically proved.
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