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Evolution of intraspecific diversity of invasive pathogen of alder Phytophthora ×alni
Pecka, Štěpán ; Koukol, Ondřej (advisor) ; Sedlářová, Michaela (referee)
Phytophthora alni s. l. (Peronosporomycetes: Stramenopila) is an invasive pathogen causing phytophthora root and collar rot in alders. It has been known from Europe since the '90s and from the Czech Republic since 2001. Three species were found are known within species complex P. alni s. l. Two of these species hybridized in Europe and created third triploid species called Phytophthora ×alni (Phytophthora alni subsp. alni). Dozens of genotypes have been identified with the help of microsatellites in previous studies, nevertheless only one genotype (Pxa-1) was dominating and most of other genotypes were closely related to it. The trend of increasing or decreasing incidence of this genotype differed among these studies. This thesis compares changes in the P. ×alni population in Vltava basin over the last 14 years during which a significant decrease in number of available hosts of this pathogen took place. Multilocus genotypes were determined using a set of 10 microsatellite markers. Among the 94 P. ×alni isolates reliably genotyped, 23 were of different genotypes. None of these genotypes, however, were found on the same localities repeatedly (except the dominant genotype). Incidence of the dominant genotype increased over time (from 63 % to 86 %). Most of the other genotypes were only slightly...
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Dispersion and survival of Moorhen (Gallinula choloropus) in urban habitats
Vodičková, Barbora ; Musil, Petr (advisor) ; Reif, Jiří (referee)
Presence of Common Moorhen (Gallinula chloropus) in Prague is a long known fact. Mapping and data collecting of this species during winter is on a low level, so there is not many information about its winter behavior. Present climate change brings not only a change in climate, but in combination with rapid urbanization, also big changes in environment. Wintering locations are moving to the north due to higher temperatures, and also to the cities. This could be fatal for many individuals. Weather is unpredictable and during wintering season of 2016/2017 and 2017/2018 there were very unorthodox winter conditions, which had a significant impact on bird population in Prague. During winter 2016/2017 there were extermely low temperatures with median deep below zero degrees Celsius in combination with large snow coverage. Winter 2017/2018 was overall good for surviving. Reason for great decline in numbers was caused not only by climate and weather conditions, but also by wrongly chosen wintering location. Unique locality of Zoological garden of Prague in Troja district, offers safe shelter even during extreme weather conditions such as freezing cold temperatures. According to statistics , this location is best suited for survival. Keywords: wintering, Common Moorhen, weather, still waters, rivers,...
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Analysis of Water Bodies on Aretin map of Bohemia
Povolná, Lucie ; Čábelka, Miroslav (advisor) ; Bayer, Tomáš (referee)
This bachelor thesis dealt with the personality of Pavel Aretin, his map of Bohemia from 1619 and its other editions. The main goal of this work was to analyze the leadership on selected editions of Aretin's map from the funds of the Map Collection of the Faculty of Science, Charles University and the National Archive, to perform a basic content and cartometric analysis. The content analysis was focused on the line and area elements of water on Aretin's maps. Changes in the representation of the waterworks during the four editions of Aretin's map of Bohemia and differences in topography from the present were examined. The content analysis included analyzes of map features and descriptions of water bodies. The cartometric analysis focused on the accuracy of the map layout according to identical points awarded to objects related to the water theme. This analysis was performed in MapAnalyst software.
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The impact of eutrophication on fish in running waters
Jeníšová, Karolína ; Horká, Petra (advisor) ; Frouzová, Jaroslava (referee)
Eutrophication belongs among be the most serious factors threatening freshwater ecosystems. Eutrophication is a result of excessive nutrient loading which comes mostly from both the point-source and diffuse pollution and agriculture, increased sediment loading from soil erosion, but also due to a presence of various types of impoundments, which, particularly in some areas, represent a significat part of nutrient supply. Although the effect of eutrophication on freshwater fish communities has been thoroughly studied in standing waters, very little attention has been paid to running water ecosystems. Among the processes with the most pronounced impacts on fish communities are increased phytoplankton growth and loss of macrophytes, low oxygen levels or anoxia, occurrence of toxic forms of nitrit and ammonia and elevated turbidity and subsequent light reduction. Whilst the diversity of fish communities is not usually affected, changes in structure of fish communities and decreased ecological quality has been detected with the increasing level of eutrophication. The most sensitive fishes are salmonids as they have high oxygen demands and are very sensitive to a toxic forms of nitrogen. Moreover they are visual predators highly affected by the increased turbidity of water environment. Percids are mainly...
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Influence of reservoirs on communities of river flow
Lavičková, Šárka ; Černý, Martin (advisor) ; Tátosová, Jolana (referee)
Construction of dams significantly affects the chemical, biological and physical properties of the flow below the dam. These changes include a decrease in the numbers of individuals one or more species, the complete disappearance of species, or the introduction of non-native species. Disruption of natural water flow also applies to animals, who have only one stage of their life (usually reproduction) connected with the aquatic environment, although they are not permanent residents. Also necessitate significant changes in the life cycles of native plants and animals near the regulated river. Basic principles of behavior impounded flow describes the concept of serial discontinuity, which assumes that the construction of the dam will break river continuum, which then causes changes in river communities. Undergoing significant change such as flow regime in the river below the dam, the most striking changes are caused by the flow hydroelectric power stations. In addition, a temperature change in the flow decreases turbidity and often the availability of nutrients, because the location of the dam with the usual outlets (high or medium) acts as a trap sedimentary particles of organic and inorganic origin. It is important but also the contact area of the river, for example, reducing the zaplavovaného...
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Development of water law in Czech lands before 1914
Urban, Michael ; Kindl, Vladimír (advisor) ; Soukup, Ladislav (referee)
The purpose of this thesis was to capture the development of legal regulation of the Czech water law and of water-law relationships, and to point out that miller's law, fisheries law and navigation law are naturally related to the water law. Water transport and handling were not regulated in any manner in the most ancient times. The Czech water law was built on the heritage of the Roman legal culture. From the end of the 10th century, the first mentions of water-law relationships can be found, particularly in monarch's charters. The first important legal regulations related to water included the Mining Code (Ius Regale Montanorum) by king Wenceslas II of 1300-1305 and the Code Maiestas Carolina by king Charles IV, which was not implemented in practice, though. The so called lawbooks are another significant resource for understanding legal regulations related to water. Elements of a complex legal regulation with statewide legal force started to be applied from the end of the 15th and in the course of the 16th century - a number of municipal establishments and the code of municipal law created by Pavel Kristián of Koldín. A considerable boom of legal regulations with respect to all aspects of water-law relationships was seen during the reign of Maria Theresia and Joseph II (the navigation patent,...
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