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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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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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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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