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A comparison between paleo and recent freshwater diatom communities from Vega Island, Antarctica.
Bulínová, Marie ; Kopalová, Kateřina (advisor) ; Spaulding, Sarah (referee)
In Antarctica, diatoms inhabit multiple limno-terrestrial habitat types, which may each individually offer unique ecological information for use in biomonitoring, paleoecology, and biogeography. However, we are still at the initial exploration stage of documenting the diversity among habitat types from different Antarctic regions, which is necessary to serve as baseline data for the aforementioned scientific disciplines, and ultimately inform conservation decisions. To gain insight into the spatial and habitat controls on Antarctic diatom communities, the importance of habitat type and island aspect was investigated by studying diatoms living in ponds, mosses, streams, and seepage areas on two opposite sides Vega Island, Antarctic Peninsula. A diverse flora of 136 taxa belonging to 31 genera was revealed, which was dominated by the genus Nitzschia, and suggests that the flora of Vega Island is biogeographically influenced by both continental and Maritime Antarctic bioregions. Habitat type was found to be a crucial factor for diatom community composition, and was stronger than the influence of island aspect. In ordination analyses, moss samples were separated primarily by their abundances of the diatom Chamaepinnularia krookiformis, while pond samples were separated by Nitzschia paleacea and stream...
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Subfossil Cladocera as a powerful tool for paleoecological reconstruction
Bubenková, Anna ; Tátosová, Jolana (advisor) ; Kopalová, Kateřina (referee)
This bachelor thesis is a literature review documenting the usage of subfossil Cladocera in paleoecological reconstruction. Its aim is to argue for subfossil Cladocera as an effective means of studying historical evolution of lakes and identifying significant processes which formed them over time. Furthemore, this literature review critically evaluates some of the most common approaches to reconstructing changes in climate, water levels, acidification, and eutrophication, and numerous issues they often encouter. The correct interpretation is vital because all the factors in the aquatic environment are connected. Despite some debate, subfossil Cladocera are an important aspect of paleoecological reconstructions with much possible utilization in future research. Key words: subfossil Cladocera, paleoecology, reconstruction
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The diversity of diatom genera: relationship to genetic variability within the genus Frustulia and the role of geography
Vrbová, Kateřina ; Kulichová, Jana (advisor) ; Kopalová, Kateřina (referee)
The occurrence of some diatoms depends on degree of pollution and water quality. Due to this attribute are diatoms used as indicators for the environmental bioassessment. But the maximum use of diatoms for this purpose is complicated by high number of species which are defined based on the ultrastructural morphological features which are indistinguishable without the electron microscope. The aims of this study were to find out the influence of environmental factors, types of habitat and geography on the structure of diatom community. And find out if richness of higher taxonomic levels is correlated with species richness, in this case if it responds with the genetic diversity within diatom species complex Frustulia crassinervia-saxonica. In this study, 49 permanent slides from natural samples were analyzed. Samples were taken from benthos of different types of freshwater habitat - lakes, dams, pools, peat bogs, stream, wet wall on diverse localities in Europe, Canada, Greenland, Chile and New Zealand. In all slides were counted 300 cells which were determined based on the morphological features on genera level. Altogether 43 benthic genera were identified. The results of this thesis showed that number of genera correlated with pH gradient but do not correlate with other environmental factors -...
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Desiccation as a structuring factor in desmid communities
Jirková, Kateřina ; Neustupa, Jiří (advisor) ; Kopalová, Kateřina (referee)
Desmids are an important part of the phytobenthos in the wetland ecosystems. These ecosystems are often ephemeral and changes in the hydrological regime is a typical characterisic of this habitat type. Dessication is a significant stress factor that affects water organisms. Different species differ in their extent of tolerance to dessication stress and it can affect their community structure and also their phylogenetic diversity. Two sites, the nature reserve Borkovická Blata and the nature locality Na Plachtě, were selected for this work. Ephemeral (seasonally dessicating) and permanent pools differed in the structure of desmid communities but the difference was signifacant only for Borkovická blata. At both localities, the samples from the dessicating pools showed in average lower species richness and Shannon's diversity index than samples from non-dessicating pools, but the differences between these groups of samples were not statistically significant. Phylogenetic analysis showed that the desmids community were phylogenetically overdispersed; closely related species tended to not appear together on the same sites at both localities. The difference in the phylogenetic structure between ephemeral and permanent was detected only in the Borkovická blata site, where the ephemeral pools exhibited weaker...
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Biogeography and habitat preferences for genus Luticola
Hanišová, Lucie ; Kopalová, Kateřina (advisor) ; Kulichová, Jana (referee)
The genus Luticola is one of the most species rich group belonging to the diatom class (Bacillariophyceace) containing 204 described species. The aim of this work is to summarize the available literature on the genus Luticola concerning its biogeography, habitat preferences of polar and temperate species, and their ecological treshold for important factors relating and forming their presence - pH and conductivity. Records suggest that the Luticola genus is presence worldwide, with higher species diversity in Europe, South America and the Antarctic region, the latter of which harbors a substantial amount of endemic species. In terms of habitat preference, records suggest that temperate species occur mostly in aquatic habitats, while polar species occupy terrestrial environments. Polar species also differ from temperate species by occupying narrower margin of pH values. However, both groups prefer low conductivity, and most species of the genus Luticola are located in environments with values up to 100 μS/cm. Key words: biogeography, conductivity, Luticola, pH.
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Taxonomy, diversity and ecology of freshwater diatom communities (Bacillariophyta) from moss habitats of Gough Island (southern Atlantic Ocean)
Vinšová, Petra ; Kopalová, Kateřina (advisor) ; Sabbe, Koen (referee)
The present study shows the results of a taxonomic and ecological survey on moss- inhabiting diatoms from Gough Island (40ř21' S, 9ř53' W). An analysis of more than 100 samples resulted in 141 identified diatom taxa, of which 21 were described by Carter (1966) and have not been reported elsewhere. Illustrative analyses of diatom communities from Tristan da Cunha and Inaccessible islands revealed an additional nine taxa, but an otherwise highly similar flora. The observed flora was highly disharmonic in its composition, represented by only a few diatom genera (i.e. Eunotia, Pinnularia, Psammothidium and Chamaepinnularia), a feature typical for oceanic islands. Also, few diatom species dominating the flora were unique to the Tristan da Cunha archipelago (Gough Island in particular) and possibly endemic, or cosmopolitan in distribution. Diatom taxa being typical for sub-Antarctic islands haven't been observed in larger amount. This, together with the highly specific diatom flora of Gough Island, resulted in very low similarity values between Gough and the other islands of southern ocean. The closest to the Tristan da Cunha archipelago based on its flora was identified to be Ile Amsterdam from the south Indian Ocean, implying the influence of west-wind drift. To investigate the diatom flora...
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Biogeographical position of the Tristan da Cunha archipelago based on floristic records.
Vinšová, Petra ; Kopalová, Kateřina (advisor) ; Žárský, Jakub (referee)
The archipelago Tristan da Cunha is situated in the South Atlantic Ocean, about midway between South America and southern tip of Africa. It represents one of the least disturbed temperate island systems in the world, supports many endemic plant and animal species. Although the locality is interesting by many aspects, many fields still remain under-studied. This bachelor thesis presents a synthesis of available literature about the archipelagos non-marine non-vascular floras, which are of a great diversity, but mostly still overlooked by scientist. For some of them were made lists of taxa present. Further, the distributional ability and patterns of this plant groups are discussed. KEYWORDS: Tristan da Cunha; Oceanic islands; Botanic; Distribution; Island Biogeography; Lichens; Mosses; Liverworts and Hornworts; Diatoms;
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Taxonomy, ecology and biogeography of aquatic and limno-terrestrial diatoms (Bacillariophyta) in the Maritime Antartic Region
Kopalová, Kateřina ; Nedbalová, Linda (advisor) ; Sabbe, Koen (referee) ; Jüttner, Ingrid (referee)
Diatoms (Bacillariophyta) are one of the most diverse algal groups in the Antarctic Region and play a dominant role in almost all freshwater and terrestrial ecosystems. Despite this overall occurrence, little is known about the diversity, ecology and biogeography of this group in the Maritime Antarctic Region. The main objective of this thesis is therefore to define the taxonomical, ecological and biogeographical characterisation of aquatic, semi- aquatic and moss-inhabiting diatom communities from two islands in the Maritime Antarctic Region: James Ross Island and Livingston Island, located on opposite sides of the Antarctic Peninsula. In this study, a total of 250 samples from three different habitat types (lakes, streams & seepage areas and mosses) from Byers Peninsula (Livingston Island) and Ulu Peninsula (James Ross Island) have been analysed. Using light and scanning electron microscopy, a rather diverse diatom flora composed of 178 taxa, belonging to 43 genera has been identified. Although even until recently, it was generally accepted that the Antarctic diatom flora was mostly composed of cosmopolitan taxa, several new species could be described as a new for science during this PhD study (a reflection of this work is presented in chapters 2 & 3 and in Appendices). Habitat type and...
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