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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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Application of stable isotope techniques for verifying the geographical origin of endangered plants and animals subject to international trade
Kopecká, Ivana ; Jandová, Kateřina (advisor) ; Horká, Petra (referee)
Elements in nature can exist in several versions, which differ in the amount of neutrons in the nucleus. These modifications are called isotopes. Neutrons have a neutral charge, but do not have a zero weight, therefore isotopes of a single element are differ in weight. Thanks to the sensitive analytical methods, we can discern that the isotope in the sample is contained in what quantity (mass spectrometry is used, from which to retrieve the ratio of stable isotopes in a sample). This can be used in many fields, such as in geology, food ecology, or discovery of geographic origin. The aim of the thesis is in the published literature to determine the extent to which the method of analysis of stable isotopes usable to verify the geographical origin of endangered species of flora and fauna subject to international trade, especially turtles of the genus Testudo. Turtles of the genus Testudo are protected by CITES treaty, which limits, enables and disables trading in endangered species so as to avoid their extinction caused overexploitation for commercial purpose. However, there is still an illegal trade that the supervising authorities are trying to detect and combat. Key words: traceability, provenance determination, authentication, CITES treaty
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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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