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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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Can anatomy and morphology of seagrass root systems predict their colonization by symbiotic fungi?
Bulínová, Marie ; Vohník, Martin (advisor) ; Votrubová, Olga (referee)
Seagrasses are narrow ecological and taxonomic group of plants which evolved from terrestrial ancestors some 100 million years ago. Unlike most terrestrial plants they are traditionally considered as a group not forming mycorrhizal symbioses or specific root endophytic associations. However, this opinion is likely biased by a very low number of studies targeting this group of vascular plants. For example, an anatomically and morphologically unique endophytic fungal symbiosis was recently discovered in the roots of the Mediterranean endemic species Posidonia oceanica, a species that is considered to be one of the best studied. It thus seems that more specialized research can yield similar results, i.e. discoveries of new fungal association in seagrasses. This could have a big impact on our opinions regarding not only mineral nutrition of these fascinating plants. The aims of this thesis therefore are 1) to summarize published information about fungal associations in the roots of seagrasses, 2) to summarize basic knowledge of anatomy and morphology of the roots of individual groups of seagrasses and 3) an attempt to predict seagrass groups where we may more likely assume presence of fungal associations. Special emphasis will be placed on the genus Posidonia which has an evolutionary origin in the...
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