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Czech Contexts of the Corpus al-Sufi Latinus
Hadravová, Alena ; Hadrava, Petr
The contribution is based on a study of manuscripts of corpus al-Sufi Latinus carried out in connection with the preparation of an edition of the ms. Praha, The Royal Canonry of Premonstratensians at Strahov, DA II 13 (al-Sufi, Catalogus stellarum fixarum, The Catalogue of Fixed Stars).
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Impact of catastrophic flood on the species and size composition of the diet of kingfisher (Alcedo atthis)
Hadravová, Alena ; Čech, Martin (advisor) ; Porkert, Jiří (referee)
A B S T R A C T This study examines the impact of catastrophic flood on the species com- position and size of fish prey in the diet of kingfisher (Alcedo atthis) nest- ing in Prague's Botič stream in 2013. Floods in June 2013 affected mainly Bohemia and partly Moravia. The streams across the Vltava river basin, in part of the Elbe river basin and marginally in the Thaya river got swollen. The effect of the flood on the Botič stream was further ampli- fied by draining of water from the dam Hostivař. Hundred and forty year water caused considerable damage to property and it is likely that it also changed the character and size composition of biota, especially fish. This change should be reflected naturally in the diet of kingfisher, which nests and hunts here. The species composition and size of fish prey in the diet of kingfisher before and after the catastrophic flood was investigated from the mass of regurgitated pellets collected from nest tunnels and chambres. In the nesting sediment, 689 head diagnostic bones (pharyngeal bones - ossa pharyngea and preopercual bones - praeoperculare) were found before the flood on Botič stream in June 2013. These bones belonged to 10 fish species and 3 families (Cyprinidae, Percidae and Balitoridae). The average length of fish was 6,5 cm, average weight 2,6 g, and the index of...
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Invasive alien mammal species in Europe
Hadravová, Alena ; Reif, Jiří (advisor) ; Lučan, Radek (referee)
The present thesis deals with the invasive species of mammals in Europe. Invasive mammals have far- reaching impacts both on the environment and on the economy. It is necessary to avoid the transfer and dissemination of such invasive species in the new environment. To prevent the spread of these species and to control them in general, it is crucial to know their characteristics and to strike at an initial phase of the invasion. The characteristics which make invasive species particularly successful in the new environment are, i.e., wide ecological valence, the ability to disseminate quickly, high competitive potential, and the potential to reproduce in the new environment. Another important factor which contributes to sustained existence of invasive species in the new environment is the absence of predators, parasites, and pathogens. Among the management practices which proved to be effective are shooting, trapping, and baiting, fencing and tree protectors are effective, too. In general, the management should be directed towards long-term reduction of population size to a predefined level based on mitigation of impacts and reduction of management costs. The EU Strategy on Invasive Species involves a three-stage approach, the three stages being prevention, eradication, and containment. All European states...
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Astronomie ve středověké Praze
Hadravová, Alena ; Hadrava, Petr
Astronomy ranked among the septem artes liberales which achieved high level at the University of Prague already soon after its foundation by the Emperor Charles IV. in 1348. Master Claretus de Solentia (Bartholomaeus of Chlumec, c. 1320-1370), who composed a didactic work Astronomicus on Charles' order in about 1350, can be mentioned as an example of scholar of this early period. At the beginning of the 15th century, Masters Cristannus of Prachatice and Johannes Sindel were very influential astronomers in Prague University. The interest of both of them in astronomical instruments can be documented by their treatises.
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