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Dynamics of dissolved organic matter depending on the activity of ants in coniferous temperate forest
Vacířová, Anna ; Jandová, Kateřina (advisor) ; Cepáková, Šárka (referee)
5 Abstrakt Soil organic matter is the largest reservoir of carbon in terrestrial ecosystems, and its functionally important component is dissolved organic matter. Its composition and changes in this composition during the vegetation season affect the vegetation, the activity of the organisms in the soil and the formation of soil organic matter. Local bio-hotspots such as anthills create spatial heterogeneity of the soil solution composition. In my work I analyzed cold water (CWE) and hot water (HWE) soil extracts, which I took in different distances from the anthill, in three soil horizons (O, A, B) three times during one vegetation season. I measured contents of carbon (C), nitrogen (N), C: N ratio and the parameter SUVA254 and SUVA280. The labile C and N content varied with the distance from the anthill. The C and N content with the distance from the anthill at O horizon increases, decreases in A and B. C: N ratio was the highest in the A horizon, but during the season the differences were not so significant. The smallest content of C and N was in April, the highest in July. The SUVA parameter in O and B decreases with distance from anthill, in A on the other hand it has risen. Ants have an effect not only on the quantity but also on the quality of the DOM, at the same time creating heterogeneity of DOM...
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Diversity of soil microbial communities in relation to biodegradation of polymers
Hušek, Pavel ; Jandová, Kateřina (advisor) ; Innemanová, Petra (referee)
Polymer materials have had a big impact on the industry in the 20th century and replaced a large amount of then used materials. Plastic waste, however, has subsequently become a big problem that needs a solution. One of the possible solutions is to produce biodegradable plastics, that should degrade in nature by themselves and therefore not increase the volume of plastic waste. Their degradation, however, is often only partial and the dynamics of polymer biodegradation in soil are not yet fully understood. In this thesis, we are investigating biodegradability of polyurethanes in field soil as it has high ecological relevance. The text consists of two parts. The first part is literary research on mechanisms of biodegradation of polymer materials and methods which are commonly used for characterization of microbial communities. The second part is our own laboratory project that aims to evaluate the effect of biodegradation of polyurethane on soil microbial communities. We assume that mostly fungi and bacteria taxa will take part in the biodegradation and will use enzymatically catalyzed hydrolysis to degrade the polyurethane foam. Key words: Biodegradation, polyurethane, soil, microbial communities, PLFA
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Factors affecting success of eradication campaigns of invasive plant species
Novotná, Tereza ; Pergl, Jan (advisor) ; Jandová, Kateřina (referee)
Increasing trade and human movements are responsible for species exchange at large scale causing several negative effects on biodiversity and human socio- economy. Introductions of new species outside their native range by humans, represents the first step in the process of biological invasions. One of the key questions related to biological invasions is how the impact of alien species can be minimized and what are the most efficient ways of management. My work is aimed to collating various information on management of invasive species in Prague, Czech Republic with special focus on identification of how many financial resources are invested to eradications, which species are being managed, and which factors affect the output of management. Several studies have identified key factors that affect the success of eradication campaigns: the spatial extent of the infestation, the reaction time, and the level of biological knowledge of the organism. Socio-economic factors, including the resources invested to eradication, are rarely available, and their effect is therefore seldom evaluated.
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Ethical aspects of Ultimate Frisbee
Jandová, Kateřina ; Parry Martínková, Irena (advisor) ; Slepičková, Irena (referee)
Title: Ethical Aspects of Ultimate Frisbee Objectives: The purpose of this study is to introduce one of the recent team sports - ultimate frisbee - in the matter of its ethics. The work is divided into two thematic parts. The first one deals with general introduction of the fair play problemacy including also the issue of the referees/umpires. The second part presents ultimate frisbee covering its history, game rules and the idea of the Spirit of the Game. Futhermore, the study also contains comparison of the ethics of ultimate frisbee and other team sports. Keywords: Ultimate frisbee, Spirit of the Game, ethics of sport, values in sport, referee
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Secondary metabolites, allelopathy and their significance in the invasion of Heracleum mantegazzianum
Jandová, Kateřina ; Dostál, Petr (advisor) ; Frouz, Jan (referee) ; Valterová, Irena (referee)
One theory concerning the invasiveness of exotic plants suggests that they exude allelopathic compounds that are novel in areas being invaded. Here, I tested for allelopathic effects of root exudates of the invasive plant Heracleum mantegazzianum (giant hogweed) in a series of experiments both in vitro and in the garden, and compared them with effects of its native congener H. sphondylium (common hogweed) and two less related native species. Moreover, I addressed intraspecific variability of allelopathy by comparing effects of 41 different maternal lines of H. mantegazzianum sampled from several areas and populations within the Czech Republic. Not only the effects, but also the identity of allelopathic compounds was investigated. In order to test also for the interaction of allelochemicals with soil microorganisms, I analysed the composition of soil microbial communities expressed as phospholipid and neutral lipid fatty acids (PLFA and NLFA, respectively) together with nutrient conditions and light availability at invaded sites in the Czech Republic. The results show that H. mantegazzianum is able to exert phytotoxic effects in vitro as well as in the garden experiment; however, its effects did not differ from the inhibition caused by the native species tested. Variation partitioning among areas,...
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název v anglickém jazyce není uveden
Jandová, Kateřina ; Langmeier, Miloš (advisor) ; Mareš, Jan (referee) ; Hach, Petr (referee)
Hypoxia of the brain as well as the subsequent reperfusion can seriously alter the tissue microenvironment and result of the functional and structural changes of nerve and glial cells. Results of experimental studies show that some ions (e.g. Mg2+) can interfere with the brain development. To answer the question whether magnesium can modulate changes of neuronal circuits induced by hypoxia and reperfusion effect of magnesium administration on the density of nitrergic neurons (NO synthesising neurons) in the rats exposed to repeated hypoxia during the postnatal ontogeny (12, 25, and 35-day-old) was studied. NO synthesising neurons were identified according to the presence of NADPH-diaphorase (NADPH-d), the enzyme co-localized with NO synthase. Results have shown that the long-lasting intermittent hypobaric hypoxia brings about the increase of the density of NADPH-diaphorase positive neurons in all studied regions of the hippocampus in 12-day-old animals, in 25-day-old only in the hilus of the dentate gyrus, and in 35-day-old in CA1, CA3 hippocampal regions and in the ventral blade of the dentate gyrus. Contrary to that, decreased density of nitrergic neurons was found in groups of animals exposed to hypoxia till the age of 25 days in both blades of the dentate gyrus and in 35 days in the ventral blade and...
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Analysis of Decision-Making Processes in the Company
Jandová, Kateřina ; Černý, Jan (advisor) ; Tomášek, Lukáš (referee)
The bachelor thesis deals with decision-making processes in a given company. The concrete decision-making process is the product pricing. The theoretical part of this thesis describes theoretical characterization of this problem, its structure, methods of solutions and factors that operate in whole process of product pricing. A part of theoretical part is also product mix that makes the basis for that decision-making process. In analytical part is description of product portfolio of selected company. These is also chosen several concrete products that show the chosen methods of product pricing used in this company. Tha part of the thesis are author's comments on this issue.
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