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The usage of fish otholits for environmental studies
Tůmová, Eliška ; Frouzová, Jaroslava (advisor) ; Slavík, Ondřej (referee)
Otoliths are small, white minerals mostly composed of calcium carbonate. They are located in inner ear of fishes and provide balance and hearing. To the biologist, the otoliths are one of the most important structure for understanding the annual age, where and in which conditions the fish was living, and even what was its diet. This paper is focused on summarizing and ordering the use of otoliths, what methods do we use and possibilities of applications in environmental studies. Key words: otolith, fish age, fish population, chemistry otoliths, microstructure of otoliths, chemistry otoliths, fish growth
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Within-group fish behaviour: effect of common experience
Fořt, Martin ; Slavík, Ondřej (advisor) ; Frouzová, Jaroslava (referee)
Recently, behavioral studies focusing on social relationships of fish in groups became popular. Fish are able individually recognize conspecifics or even heterospecifics. This ability allows distinguishing among individuals in and between groups and shows that fish prefer associating with familiar or kin individuals. An interaction with kin individuals is called condition-dependent recognition, whilst relationship based on previous experience is called condition independent recognition or familiarity. Both of these interactions can bring the participants some advantages, such as better protection from predators, foraging benefits, lower aggression levels, etc.
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Stanovení vzorců selektivního chování rybářů ve statistikách českého rekreačního rybolovu
Jankovský, Martin ; Pivnička, Karel (advisor) ; Slavík, Ondřej (referee) ; Adámek, Martin (referee)
Methods for detecting patterns of angler selective fishing behaviour in the long term recreational fishery statistics are presented in this Ph.D. Thesis. The motivating idea is that mainly different anglers' fishing preferences or attitudes towards particular fish species obstruct applying anglers' catches data for ongoing use in ichthyology research. Better recognising angler selectivity is therefore judged to be the key point from the viewpoint of fish and fishery sciences. Methods affecting angler behaviour can be directly applied by other specialists, e.g. social scientists. The thesis consists of five papers two of which are published (paper 1, 2), other two of which are accepted for publishing (paper 3, 4) and the last of which (paper 5) is in the status of manuscript before submitting. In the first two papers the role of common carp catches is focused. By using multivariate techniques it is studied if the increased exploitation of carp increases also the exploitation of other fish species. Time series of carp catches serve as an explanatory variable, other species catches through the same time are processed as independent variables. According to expectations the positive effect of carp catches on those of the other species was approved at the river section with the highest expected density...
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Fish and benthos of the Černá Nisa stream and their contamination by metals in the period of recovery from acidification
Burdová, Lucie ; Hořická, Zuzana (advisor) ; Slavík, Ondřej (referee)
The aims of the thesis were to compare chemistry of the Černá Nisa stream in the Jizera Mountains (Northern Bohemia, Czech Republic) at the end of the era of strong anthropogenic acidification (in the mid-1990s) and in the period of the recent intensive chemical and biological recovery from acidification, and to study the present biota of the stream. During the year 2008, physical and chemical parameters of the water were studied, the species and age composition of ichthyofauna, and the quality and quantity of macrozoobenthos - the main component of the food for fish. Special attention was paid to the content of toxic metals (Be, Al, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Cd, Pb, Hg) in the water, main representatives of benthic organisms, and in selected tissues of brook charr. The comparison of the water chemistry with results from the years 1994, 1996, and 1997 showed a decrease in acidification, despite the unstable chemical climate during the seasons, and sulphate and nitrate concentrations still high. Since the mid 1990s, the stream has been inhabited by a stable population of brook charr (Salvelinus fontinalis), a non-native, highly acid-tolerant species, which is now dominating there. At present, also a stable population of a native species, common minnow (Phoxinus phoxinus), occurs in the stream....
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Biomechanical aspects of the reconstruction of the acetabulum
Slávik, Ondrej ; Marcián, Petr (referee) ; Florian, Zdeněk (advisor)
The research part of bacelor’s thesis Biomechanical aspects of the reconstruction of the acetabulum is dealing with historical development and current methods of solving the issue of pathological hip joints in case when use of total endoprosthesis is not suitable, for example in children. Also the anatomical view, related to the given problem situation, is outlined and the most significant disorders of the hip joint, which are connected with these cases, are characterized. In the practical part of this work, there are results of the analysis model between pathological and physiological hips analyzed and qualitatively compared, followed by the solution of the concact forces in these two situations.
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