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The morphology of avalanche paths
Krause, David ; Křížek, Marek (advisor) ; Treml, Václav (referee)
An avalanche path is a landform, that is being modeled by surface snow avalanches, debris flows and other slope processes. It consists of starting zone, track and runout zone. The submitted bachelor thesis is concerned with the characteristics of avalanche paths used in literature and generates their classification. The morphometric GIS analysis is performed in the Eastern High Sudetes. The measured vlaues of 16 avalanche paths from 6 sites are statistically processed and compared. The Sudetic paths are shorter but they have similar slope in comparison with paths in alpine environment. The spatial distribution of avalanche paths is bound to lee parts of the anemo-orographic systems. The aspect is predominantly southeastern, the slope is between 20 and 30ř and the length is usually between 200 and 400 m. The path lenght depends inversely on the slope of the starting zone. There is also a relation between the avalanche path morphology and the area of alpine tundra on the etchplain above the timberline, from where the snow is being blowed to the starting zones. Key words: snow avalanche, morphometry, Eastern High Sudetes, Altvatergebirge, Glatzer Schneeberg
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Planation surfaces in the Hrubý Jeseník Mts.
Jablonská, Danica ; Křížek, Marek (advisor) ; Štěpančíková, Petra (referee)
Remnants of planation surfaces in Hrubý Jeseník were noted in many geomorphological studies made in the studied area. However, the levels of planation surfaces were never described. The present study deals with the determination of the levels of planation surfaces (the amount of levels) and its connection to neotectonics. The whole area was divided into three parts (Pradědská, Keprnická and Orlická part). Histograms of elevation frequency, the cumulative graph of the area of planation surfaces and the statistical test show six levels of planation surfaces. Six levels were determined in Pradědská and Orlická part and four levels in Keprnická part. The levels of planation were compared to similar areas in the Sudetes. These intervals have significant representation of the flat surfaces within. Six levels of planation surfaces were determined. The main periods of uplift were presented based on the intervals between the levels of planation surfaces. The minimum uplift in the central, most active part is estimated to be 450 m.
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Development of fluvial lakes in the Lužnice River floodplain
Hastíková, Petra ; Šobr, Miroslav (advisor) ; Havlíková, Petra (referee)
The object of the thesis is to evaluate the development of several chosen fluvial lakes in the basin of the river Lužnice, mainly in the section between the border with Austria and Suchdol nad Lužnicí. The river Lužnice in this particular section represents low intensity of modification. Many fluvial lakes are situated there and the river is meandering remarkably in the area. The first part of the thesis deals with the characteristics of the natural conditions in the basin of Lužnice and the defined floodplain and the problematics of lakes and their determination. The main part of the thesis focuses on the evaluation of the flow development and fluvial lakes of the Lužnice floodplain based on the data of a aerosnapshoting. Because of the gradual decease of the meanders and straightening of the flows, it is possible to claim that the river has been considerably shortened with the passing time. In the thesis, 34 chosen fluvial lakes, that were measured morphometrically and batymetrically, were studied in detail.
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Postnatální změny střeva králíka.
ŠTĚCHOVÁ, Kristýna
The small intestine is an important organ of the gastrointestinal tract. It is undergoing the influence of internal and external factors significant adaptive changes in the postnatal life. The aim of the thesis was to provide information about the morphometric changes in various sections of the small intestine of rabbits during the 19 days of postnatal development study. It was measured length of the individual sections of the small intestine at the age of 0, 5, 10, 14 and 19 days and it was sampled for morphometric examination mucosa. The length and width of villi, the depth of crypts of Lieberkühn and the height of enterocytes were evaluated under a light microscope. The average length of the small intestine was 61,4?2,4 cm at new born rabbits and when they were 19 days old it was 106,5?9,1 cm. The most noticeable increase was observed at ileum (124,4 %). On the contrary the lowest increase was observed at jejunum (63,1 %). In the duration of 19 days development of the rabbits, the highest size of villi and crypts of Lieberkühn was in duodenum, on the other hand the lowest was in jejunum. We could also observe temporary stagnation of the growth of enterocytes in all parts of the small intestine. From the results follow that in the duration of the early postnatal development, it is duodenum, which is able to adapt in the fastest way
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Individual growth and variability of early development stage of creeping water bug Ilyocoris cimicoides (Heteroptera: Nepomorpha:Naucoridae)
PILAŘOVÁ, Simona
This thesis investigates an influence of environmental variables (temperature and food availability) on development and growth of the first three nymphal stages of Ilyocoris cimicoides Linnaeus, 1758 Individuals were housed individually in experimental cages from eklosis into adulthood. Experiments were carried out in a combination of four different temperatures (17 ?, 19 ?, 22 ? and 25 ? C) and two different modes of food availability (full-fed every day, red-fed every other day) (in eight treatments). The temperature significantly influenced the length of nymphal development. According to our expectation, shortest development was achieved in individuals reared at 25° C. Development period was prolonged by decreasing temperatures. Unpredictably, the nymphs of the 3rd instar had longest development at the lowest temperatures (17 ? C) whereas nymphal development of the 1st and 2nd instars ran faster Both, the lowest- (17 ? C) as well as the highest used temperature (25 ? C) are probably very close to the temperature limits, that corresponds to the limits of postembryonic development. The optimum temperature for development was 22 ? C. Furthermore, it has been found that food availability should also significantly affect growth and development. Surprisingly, less mortality was observed in individuals reared in reduced feeding treatment, except the only case - nymphs reared in low temperature (19 ? C), where higher mortality was found in individuals reared at the same food availability.
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Morphological analysis of the tapeworms eggs of the order Diphyllobothriidea
LEŠTINOVÁ, Kateřina
The order Diphyllobothriidea is a unique group of tapeworms in terms of the wide spectrum of definitive hosts involving all groups of tetrapods including man. They are almost globally distributed in both freshwater and marine ecosystems, but there are also terrestrial species. It is very difficult to identify species of diphyllobothriid cestodes to the species level. Morphology of the eggs might represent a new method in the differential diagnosis of these parasites. Besides the size and shape of the eggs, the structure of egg surface might play a significant role in the determination of different taxa. For the analysis of these characteristics Scanning Electron Microscopy (SEM) was used. Experimental infections in hamsters and man were done.
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Morphometric analysis of two species Ameiurus melas and Ameiurus nebulosus, (Teleostei: Ictaluridae) occurred on territory of Czech republic
PÍCHA, Roman
North American freshwater catfishes (Ictaluridae) is family of freshwater catfishes and includes 7 genera and 48 species. Original habitat of those family is Northern and Central America, but some species were to be introduced to the other regions inclusive Europe. In Czech Republic was recorded occurrence of two species of genus Ameiurus. Brown bullhead (Ameiurus nebulosus) imported by J. Šusta in 1890, and black bullhead (Ameiurus melas), which was imported in 2003 as an admixture to load of Common carp stocking material from Croatia. Distribution of these species is restricted on a small areas in the Elbe river basin and Třeboň pond system in Southern Bohemia. These species are very similar and their resolution is possible only on the basis morphometrics and anatomical diversity (number of fin rays, serration of spine on pectoral fin). Therefore was necessary carry out detailed measuring of both species with the aim of find out appropriate next differences. We measured 63 measurements by digital slide gauge and next we quantified number of fin rays. Totaly was processed 90 black bullheads and 52 brown bullheads.
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Biological characteristics and meaning of bullhead catfishes in waters of Czech republic
PÍCHA, Roman
Bullhead catfishes (Ictaluridae) is family of freshwater catfishes and includes 7 genera and 48 species. Original habitat of those family is Northern and Central America, but some species were to be introduce to the other regions inclusive Europe. In Czech republic was recorded occurrence of two species of genus Ameiurus. Brown bullhead (Ameiurus nebulosus) imported by J. Šusta in 1890, and black bullhead (Ameiurus melas), which was imported in 2003 as an admixture to load of Common carp stocking material from Croatia. Their distribution is restricted on a small areas in Elbe valley and Třeboň pond system in Southern Bohemia These sorts are very similar and their resolution is possible only on the basis morphometrics and anatomical diversity (number of fin rays, serration of spine on pectoral fin). Therefore was necessary proceed closer investigation individuals hunted on territory of Czech republic with the aim of evidence occurrence of black bullhead and valorize influence of these species on our original fish species.
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