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Hydrological drought in the context of climatic change in the world and in the Czech part of Elbe River basin
Šachová, Barbora ; Kocum, Jan (advisor) ; Janský, Bohumír (referee)
Hydrological drought in the context of climatic changes in the world and in the Czech part of Elbe River basin Abstract The submitted thesis deals with the hydrological drought as one of extreme runoff situations in relation to climate change. Part of this work is a comprehensive research sources to Czech and foreign literature defining the concepts and the development of hydrological drought due to the physical- geographic and anthropogenic factors. Low flow characteristics and methods for defining the drought events are described. Attention is paid to the possibilities of prevention and compensation of negative impacts of drought. Within the second part the presence of low flow in Elbe River subbasins, Blšanka River, Rakovnický Brook and Vydra River, is analyzed. Water deficit is evaluated with regard to the physical-geographic characteristics and the specifics of water resources use. Outline of possibilities to increase the retention capacity of study catchments is given. Key words: hydrological drought, low flow, runoff regime, retention potential, Blšanka River, Rakovnický Brook, Vydra River
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Hydrological function of peat bogs and peat water properties of the Vydra River headwaters
Doležal, Tomáš
The retention potential of landscapes, along with the water regime of spring areas, are important hydrological topics of research, particularly in the current context of increasing extreme drought frequencies. The present work is focused on monitoring the mountain peat bogs, which, due to their overall frequency of occurrence in the spring area of the Vydra river, represent a significant constituent of the rainfall-runoff process of the area of interest. The specific hydropedological features of the organogenous soils (Histosol type soil) provide the high retention potential of the area, however, the influence of these soils on the runoff process is determined by complex physicogeographical factors. The general opinion on the hydrological function of the peat bogs has changed in recent years and the most important factor in the runoff formation in the mountain area of the Šumava Mts. is now thought to be the actual saturation of the headwater, which is predominantly composed of hydromorphic and organogenous soils. The organogenous soils are significant water reservoirs and have an important impact on the landscape. However, they may also intensify the extreme values of the watercourses during extreme precipitation events. The fundamental part of this work focuses on detailed observations of the...
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Hydrological function of peat bogs and peat water properties of the Vydra River headwaters
Doležal, Tomáš
The retention potential of landscapes, along with the water regime of spring areas, are important hydrological topics of research, particularly in the current context of increasing extreme drought frequencies. The present work is focused on monitoring the mountain peat bogs, which, due to their overall frequency of occurrence in the spring area of the Vydra river, represent a significant constituent of the rainfall-runoff process of the area of interest. The specific hydropedological features of the organogenous soils (Histosol type soil) provide the high retention potential of the area, however, the influence of these soils on the runoff process is determined by complex physicogeographical factors. The general opinion on the hydrological function of the peat bogs has changed in recent years and the most important factor in the runoff formation in the mountain area of the Šumava Mts. is now thought to be the actual saturation of the headwater, which is predominantly composed of hydromorphic and organogenous soils. The organogenous soils are significant water reservoirs and have an important impact on the landscape. However, they may also intensify the extreme values of the watercourses during extreme precipitation events. The fundamental part of this work focuses on detailed observations of the...
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Hydrological function of peat bogs and peat water properties of the Vydra River headwaters
Doležal, Tomáš ; Kocum, Jan (advisor) ; Kulhavý, Zbyněk (referee) ; Tesař, Miroslav (referee)
The retention potential of landscapes, along with the water regime of spring areas, are important hydrological topics of research, particularly in the current context of increasing extreme drought frequencies. The present work is focused on monitoring the mountain peat bogs, which, due to their overall frequency of occurrence in the spring area of the Vydra river, represent a significant constituent of the rainfall-runoff process of the area of interest. The specific hydropedological features of the organogenous soils (Histosol type soil) provide the high retention potential of the area, however, the influence of these soils on the runoff process is determined by complex physicogeographical factors. The general opinion on the hydrological function of the peat bogs has changed in recent years and the most important factor in the runoff formation in the mountain area of the Šumava Mts. is now thought to be the actual saturation of the headwater, which is predominantly composed of hydromorphic and organogenous soils. The organogenous soils are significant water reservoirs and have an important impact on the landscape. However, they may also intensify the extreme values of the watercourses during extreme precipitation events. The fundamental part of this work focuses on detailed observations of the...
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Crayfishes as a prey
MAN, Milan
Due to the increase in the number of non-native species of crayfishes and their presence on more and more localities, there is the possibility of their elimination using predatory fish species. The length relationships between a prey and a predator could clarify this possibility. The aim of this bachelor thesis was to develop high quality literary review about the incorporation of crayfish into the food chain and processing samples of a perch (Perca fluviatilis) from a locality with an occurrence of juvenile crayfishes (Astacus astacus). I wanted to verify the possibility of a perch predation on juvenile crayfish individuals. However, only three crayfishes were found in the analyzed perchs. After a very low percentage of crayfishes in the analyzed perchs, a laboratory experiment was carried out with young of the year of signal crayfish (Pacifastacus leniusculus) and perchs. Unfortunately, this experiment ended unexpectedly. The crayfishes were served to perchs, but the fishes showed no interest in them throughout the experiment. The results of food analysis show, that smaller perchs are able to eat crayfish, but they are not a sought-after component of their diet. In this case, the low frequency of crayfishes in the diet was caused by enough other food (insect larvae) and also the number of shelters in the pond, where the crayfishes were reared. In the experiment, I unfortunately failed to confirm the positive relationship between a perch as a predator and a juvenile crayfish as a prey. However, the conclusions of the other studies on the use of larger perchs show the preference and high frequency of occurence of juvenile crayfishes in their diet.
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Hydrological drought in the context of climatic change in the world and in the Czech part of Elbe River basin
Šachová, Barbora ; Kocum, Jan (advisor) ; Janský, Bohumír (referee)
Hydrological drought in the context of climatic changes in the world and in the Czech part of Elbe River basin Abstract The submitted thesis deals with the hydrological drought as one of extreme runoff situations in relation to climate change. Part of this work is a comprehensive research sources to Czech and foreign literature defining the concepts and the development of hydrological drought due to the physical- geographic and anthropogenic factors. Low flow characteristics and methods for defining the drought events are described. Attention is paid to the possibilities of prevention and compensation of negative impacts of drought. Within the second part the presence of low flow in Elbe River subbasins, Blšanka River, Rakovnický Brook and Vydra River, is analyzed. Water deficit is evaluated with regard to the physical-geographic characteristics and the specifics of water resources use. Outline of possibilities to increase the retention capacity of study catchments is given. Key words: hydrological drought, low flow, runoff regime, retention potential, Blšanka River, Rakovnický Brook, Vydra River
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Helminths of the European otter
Seemannová, Kateřina ; Vadlejch, Jaroslav (advisor) ; Lukáš, Lukáš (referee)
The target of this study was to explore a distribution and prevalence of parasitic helmints in population of wild European otters in the Czech Republic. For this purpose organization ALKA wildlife o.p.s. provided 15 cadavers of these animals. This gained experimental material was consequently subjected to a detailed parasitical examination. All examinations and analises were made in the parazitical laboratory of Department of Zoology and Fishers, Faculty of Agrobiology, food and natural resources in Czech University of Life Sciences in Prague. The discovered parazitic organisms were subsequently isolated and determined. This autopsy showed the occurrence of parasitic flukes of genus Metorchis. Prevalence was counted 13.33 % (two positive samples from all fifteen samples). In the first sample, there were found 17 flukes, in the second sample, there were found 11 flukes. The place of discovery of this samples was southern Bohemia. The occurence of other expected representers of tapeworms, roundworms and acanthocephala were not confirmed. Results can be disorted because of low number of examined biological material. But getting bigger amount of material is a problem because the European otters are protected by law.
The results show that in population of wild European otters occur parasitic flukes of genus Metorchis. Since this is the first mention of their occurrence in the Czech Republic, it would be appropriate to study this issue from now to get more results that would be more exact.
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