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Effect of species composition change of forests on the quality of litter and derived soil organic matter
Roblíková, Věra ; Jandová, Kateřina (advisor) ; Bartuška, Martin (referee)
Climate change will alter the species composition of forests, which will cause changes in litter amounts and quality and potentially affect the carbon content and its stability in forest soils. With the knowledge of inputs to the biogeochemical carbon cycle, we can design methods of forest management and effectively mitigate climate change with forest cover. The aim of this thesis is to summarize information about i) change in species composition of temperate forests in Europe and the Czech Republic, ii) differences in litter amount and quality, iii) effect of litter quality on the stability of carbon in soils. I propose a master's thesis with an observational and experimental investigation of forest species change's effect on carbon content in soils. Climate change will shift species ranges northward and to higher altitudes. While species do not differ in the production of above-ground litter, they differ in the quality of above-ground litter and the quantity and quality of below-ground litter. The rate of decomposition is affected by the litter quality of tree species. Through their effect on the fauna, tree species affect the amount of carbon stored in the mineral horizon. However, the effect of litter quality on carbon stability in mineral horizons is unknown, in terms of both the density fractions of...
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Allelopathy of aquatic plants and its possible application to control cyanobacterial blooms
Kolářová, Anna ; Jandová, Kateřina (advisor) ; Kučerová, Andrea (referee)
The excessive growth of phytoplankton and the development of water bloom leading to the damage to aquatic ecosystems are becoming a more and more frequent problem. There are many methods to control the water bloom from which mainly those that use interactions of living organisms have been developing lately, with the utilisation of aquatic plant allelopathy being one of them. Allelopathy is a type of relationship between two organisms when one of them influences the other by secreting allelopathically active compounds in the environment. However, the effect of these secondary metabolites depends on many biotic and abiotic factors, which also has consequences for their potential use to control the water bloom. Although the results of many studies suggest that allelopathy can affect the community of phytoplankton, its role in aquatic ecosystems is still unclear. This thesis summarizes the knowledge about the occurrence of allelopathy among aquatic organisms, the modes of action of allelochemicals and the impacts of the key factors influencing the allelopathic effect. At the same time, it evaluates the prospects of using the allelopathy of aquatic plants to control water bloom and reviews experimental approaches to studying allelopathic interactions.
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n-Alkanes and GDGTs biomarkers in lake sediments as a tool for quantitative paleoclimate reconstruction
Machová, Tereza ; Tátosová, Jolana (advisor) ; Jandová, Kateřina (referee)
The review is divided into two major sub-sections, the first focusing on n-alkanes and the second on GDGTs. Considering n-alkanes, the carbon chain length and the predominant evenness or oddness are of particular importance to identify the source organism. However, the high species and interspecies variability in chain length associated with environmental conditions or the differences in the amount of n-alkyl lipid production are problematic. Since n-alkanes are composed of carbons and hydrogens, they can also be studied based on their isotopic composition. Plants discriminate against heavier isotopes of carbon and hydrogen during the formation of organic molecules, resulting in the production of more depleted compounds. Using δ13 C, we can determine the water availability over time or the exchange between C3 or C4 vegetation; applicability is limited by the latitude of the site or bacterial production of n alkenes. δ2 H of C17 alkane can reveal the evapotranspiration of a lake and/or the δ2 H values of lake water, nevertheless, we need sufficient concentrations of the n-alkane in question, and be sure the source of the hydrogen in the lake water hasn't been affected in the past. GDGTs use to be analyzed primarily by their structure, which may change with changes in ambient temperature, i.e. GDGTSs...
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Fish community trophic structure and interaction in riverine environment
Dalecká, Kateřina ; Horká, Petra (advisor) ; Jandová, Kateřina (referee)
In anthropogenically influenced rivers, fishes with lower environmental requirements are supposed to have an advantage over more specialised fish species. Such features include, for example, limited migration and habitat requirements, unspecialised breeding requirements or use of food resources. Guilds of sensitive species that share life history strategies that are highly adapted to specific riverine conditions have declined far more than generalist species that can survive in a wide range of habitats that are not characteristic of natural river ecosystems. In European lowland rivers, several species belong to eurytopic ecological group of fish which are often omnivorous feeders and have lower habitat requirements. It is suggested that these species are favoured by feeding omnivory in contrast to more specialised, rheophilic fishes among whose more specialised feeding can be found. The aim of our study was to evaluate the trophic niche use and interactions among eurytopic and rheophilic fish species. We hypothesized that eurytopic, omnivorous fish will exhibit a broader isotopic niche area (SEAc, TA) and higher trophic position (TP) then specialized rheophilic fish species. Isotopic niche area of species, between species niche overlap and trophic position of species in community were evaluated...
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Fish community trophic structure in antrhopogenically perturbed rivers
Dostál, David ; Horká, Petra (advisor) ; Jandová, Kateřina (referee)
Využití stabilních izotopů pro hodnocení trofické struktury společenstev nabývá v posledních dekádách na popularitě a stává se tak stále více používaným nástrojem užívaným k výzkumu trofických pozic a potravních nik. V této práci jsou shrnuty základní principy, které se při práci se stabilními izotopy využívají, představeny mechanismy výměny tkání, izotopového routingu a diskriminačního faktoru, jejichž zanedbání může vést až ke znehodnocení nabytých poznatků. Dále jsou v práci představeny základní metody využití stabilních izotopů, jejich výhody a nevýhody, matematické modely zpracování dat a jejich uvedení do praxe pomocí praktické části, ve kterém bylo zkoumáno trofické postavení a niky kaprovitých ryb v antropogenně ovlivněných řekách.
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Interpretation of carbon stable isotope data from lake sediment archives
Lánová, Zuzana ; Tátosová, Jolana (advisor) ; Jandová, Kateřina (referee)
Lake sediments consist of terrestric plant matter, lacustrine plancton primary production and microbial lake biomass. All of these organism groups discriminate during C-substate fixation and/or its further assimilation heavier and more stable 13 C carbon at a certain ratio, which is reflected by 13 C concentration in their biomass and consequently in sediments. The reason of discrimination at these enzymatically controlled biochemical reactions lies at kinetic fractionation controlled by binding energies of chemical substances. Isotopic signature contained in organic matter of lake sediments can be influenced by photosyntesis intensity, formation of anoxic zone allowing methanogenic a methanotrophic bacteries activity, lake trophic state or hydrologic isolation (long periods of drought). Keywords: Paleolimnology, carbon isotopes, discrimination processes, lake sediments
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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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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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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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Fish community trophic structure and interaction in riverine environment
Dalecká, Kateřina ; Horká, Petra (advisor) ; Jandová, Kateřina (referee)
In anthropogenically influenced rivers, fishes with lower environmental requirements are supposed to have an advantage over more specialised fish species. Such features include, for example, limited migration and habitat requirements, unspecialised breeding requirements or use of food resources. Guilds of sensitive species that share life history strategies that are highly adapted to specific riverine conditions have declined far more than generalist species that can survive in a wide range of habitats that are not characteristic of natural river ecosystems. In European lowland rivers, several species belong to eurytopic ecological group of fish which are often omnivorous feeders and have lower habitat requirements. It is suggested that these species are favoured by feeding omnivory in contrast to more specialised, rheophilic fishes among whose more specialised feeding can be found. The aim of our study was to evaluate the trophic niche use and interactions among eurytopic and rheophilic fish species. We hypothesized that eurytopic, omnivorous fish will exhibit a broader isotopic niche area (SEAc, TA) and higher trophic position (TP) then specialized rheophilic fish species. Isotopic niche area of species, between species niche overlap and trophic position of species in community were evaluated...
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