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Influence of environmental factors on fish assemblages in streams of the Elbe and Oder basins
Kůra, Luboš ; Švátora, Miroslav (advisor) ; Matěna, Josef (referee)
ABSTRACT The effects of environmental parameters on changes in the structure of fish assemblages were studied in the Elbe and the Odra river basin. Research was done at 819 sites that were surveyed in the field during the period between 1993 and 2007. The impact of 46 factors derived from the maps through a geographic information system was tested as well as the impact of 10 factors recognized in the field. To evaluate the influence of these factors the indirect (Detrended Correspondence Analysis, DCA) and direct (Canonical Correspondence Analysis, CCA) multivariate cluster analysis were used. Analyses were performed with data on presence-absence and relative abundance of each species. DCA well reflects changes in assemblages in the longitudinal profile of streams. CCA refers to a significant influence of regional and temporal variability and influence of individual factors. The fish assemblages are best characterized by the analyzed factors of distance from the source location, stream slope, altitude of locality, representation of arable land in the basin, number of ponds in the sub-basin above the locality, type of waters (salmonid or cyprinid), and water temperature (the only of the parameters of the field). The analyzed factors better reflect the variability in fish assemblages of the Odra...
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The effect of selected parameters of stream water on gill morphology of brook charr and the structure of ichthyofauna of the Jizera Mountains
Hušek, Jiří ; Švátora, Miroslav (advisor) ; Dušek, Martin (referee)
The occurrence of ichthyofauna on the territory of the Jizera Mountains (Northern Bohemia, Czech Republic) is limited, besides other factors, by the water chemistry. pH value and pH-related concentration of inorganic monomeric aluminum (Ali) are crucial parameters of the water, determining the survival of fish in streams. Low pH and high concentrations of Ali cause severe damages to fish gills. The thesis deals with the influence of the water chemistry on distribution of ichthyofauna in the Jizera Mts and gill morphology in brook charr (Salvelinus fontinalis), a dominant fish species of the upper plateau of the mountains. The results show that the species diversity of fish in acidified streams is lower than that in streams without meaningful acidic episodes. Histopathological analyses of gills of brook charr individuals from an acidified stream confirm, that low pH values and high concentrations of Ali have a cummulative effect and lead to degenerative changes on gills. Key words: The Jizera Mountains, ichthyofauna, brook charr, gill morphology, water chemistry, toxic aluminium, acidification
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Genetic variability of the genus Alburnoides in Azerbaijan
Omelchenko, Dmytro ; Švátora, Miroslav (advisor) ; Vukićová, Jasna (referee)
The Caucasus region is characterized by high rate of endemism and taxa richness of fishes. Azerbaijan is a country situated on the border between Europe and Asia with rivers flowing in the Caspian Sea. Natural environment of this country is represented by various habitats with diverse ichthyofauna. This region is very attractive for biogeographical studies because it lays on the border of two different ecoregions. Even on the modern stage of scientific cognition, there is still lack of data about freshwater fishes from that region. Spirlins or rifle-minnows (Alburnoides Jeitteles, 1861, Actinopterygii, Cyprinidae) is a genus of small freshwater fishes and it has been chosen as a focus of this thesis because of numerous reports of new species from surrounding countries. The presented thesis is one of the seldom molecular studies trying to reveal the taxonomical situation within the genus Alburnoides, describe the phylogenetic relationships between geographically isolated populations, and provide biogeographical implications for fishes in the Caspian Sea river basins. Both mitochondrial (cytochrome b, cytochrome oxidase subunit I) and nuclear (RAG1, rhodopsin) markers were used in the study and the Maximum Likelihood, Maximum Parsimony and Bayesian phylogenetic analyses were performed. Further, the...
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ANALYSIS OF AMPNIBIAN NADITAT PREFERENCES IN THE NORTH - EAST PART OF THE TŘEBÍČ DISTRICT
Jeřábková, Lenka ; Švátora, Miroslav (advisor) ; Rehák, Ivan (referee)
8 ABSTRACT In the north-east part of the Třebíč district 108 water sites were repeatedly monitored to analyze breeding of amphibians where its 11 species were proven by this research. Bombina bombina, Bufo bufo, Bufo viridis, Hyla arborea, Pelobates fuscus were proven in line with previous studies. However, species Triturus cristatus, Triturus vulgaris, Rana temporaria, Rana dalmatina, Rana esculenta synklepton were monitored in the region for the first time ever. Distinctly high values of the species presence were reached by BufBuf (60,2 %), RanEscSyn (78,7 %) and HylArb (48,1 %). In contrast, species TriCri, TriVul, BufVir, RanArv, RanDal were found in the region with low frequency. There were found positive correlations in the proportion of littoral, natant and submerse vegetation and in the transparency of the water column and in contrast negative correlations were found in the extent of urban areas and with the number of amphibians breeding in the water site. The Redundancy analysis (RDA) helped to discover statistically significant influence of the environmental variables (proportion of littoral vegetation, transparency, water site total surface and lastly number of other water sites within the range of 500 metres) on the presence of amphibians on the water sites. Consequently, "ideal breeding sites"...
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Phylogeography of the genus Squalius in Albania
Lerch, Zdeněk ; Švátora, Miroslav (advisor) ; Kalous, Lukáš (referee)
The thesis is focused on the issue of the Squalius genus phylogeography in Albania in the Balkan region. Phylogenetic analyses of sequence variation at mitochondrial genes (cytochrome b) were used to examine these issues for the freshwater fish genus Squalius from various river systems in the Adriatic Sea region. There were identified 3 genetic lineages of vague taxonomic position where the genetic variation amount to 1.6-2.1 %. The first lineage is distributed in north of Albania and in the whole Periadriatic region, the second lineage is especially spread to northern part of Albania and the third lineage covers especially the zone of the European ancient lake systems on the Balkan Peninsula (Lake Ohrid and Prespa), from where expands to the southern part of Albania. There sympatrically coincide the both lineage in the hydrological river-lake system of Drin and Skadar. The phylogenetic and taxonomic position of the Squalius genus in the region seems to be interesting topic for subsequent and more detailed study. Keywords: Squalius, Albania, cytochrome b, phylogeography
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Development of endemic freshwater ichthyofauna of Greece
Kyralová, Eva ; Vukićová, Jasna (advisor) ; Švátora, Miroslav (referee)
The Balkans is one of the hot spots of biodiversity, and is known for a high diversity and endemism of freshwater fishes. The development of Greece was significantly affected by the climatic, geologic and orogenetic events resulting in high concentration of freshwater fish endemism. Some of the important historical events were the emergence of land bridges during the early Oligocene and Miocene, through which freshwater fishes dispersed to the Balkans from Asia and subsequently to Africa, the freshwater phase of the Paratethys sea or Alpine orogeny, which began 65 million years ago, and which gradually formed the Greek mountain systems, leading to a long-term isolation of local freshwater ichthyofauna and subsequent speciation. Other major events include Messinian salinity crisis and Pleistocene climate oscillations. Most of the freshwater fish families occurring in Greece most probably originated in the Southeast Asia, from where they colonized the Balkans by several routes. These colonizations took place repeatedly at different times and by different routes. The dispersion of freshwater fishes from Asia to Europe through Siberia started before the uplift of the Ural Mountains about 33 million years ago and continued until Pliocene. Another important colonization route from Asia was via the...
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