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Diversity of the Micrasterias papillifera / M. radiosa (Desmidiales) species complex
Trumhová, Kateřina ; Šťastný, Jan (advisor) ; Mareš, Jan (referee)
This Master's thesis deals with diversity within the Micrasterias papillifera/ M. radiosa (Desmidiales) species complex. Both species are inhabitants of endangered biotops, like peat-bogs and, like other desmids, are used for biomonitoring. Many described varieties for both of them can be found in taxonomic literature, but their morphology is overlapping and revision of this species complex seemed to be necessary. All strains were isolated from peat-bogs and lakes across Europe and my dataset was properly completed by strains from algal collections. Results of phylogenetic analysis of sequences for ITS and psaA showed, that the real intraspecific diversity of Micrasterias papillifera Brébisson ex Ralfs was overestimated. Although I could find a little intraspecific diversity within the ‚papillifera' lineage in the phylogenetic tree based on ITS sequences, it did not correspond with a morphology of isolates. M. papillifera possess unexpected morphological plasticity and also some isolates designated as Micrasterias radiosa Ralfs were present in this lineage. On the contrary, there were only a few isolates in the lineage ‚radiosa'. This species seems to be relatively rare and probably has limited distribution. Both species are morphologically well delimited from each other on the basis of several characters...
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What are the effects of ombro-minerotrophic transition in Central European peatlands on structure and dynamics of microalgal communities?
Hanousková, Andrea ; Neustupa, Jiří (advisor) ; Pusztai, Martin (referee)
Peatlands, as primary boreal habitats, are very rare and valuable azonal ecosystems in the Central European landscape. Their value is due, among others, to the enormous abundance of microalgae communities, of which probably the most prominent group consists of desmidiales, both in the richness of species and in their proportional representation. An important factor that affects peatland biota is the ombro-minerotrophy gradient derived from the hydrological regime. According to this concept, peat bogs are divided into two basic types - ombrotrophic peat bogs, which are saturated only by rainwater and minerotrophic fens, which are enriched by groundwater or surface water. The desmids, characterized by high sensitivity to environmental factors and species richness, are a very useful model group for ecological studies. In my work I deal with the effect of the ombro-minerotrophic gradient on the structure, diversity and dynamics of desmid communities on Sudeten peat bogs. The results show that ombro-minerotrophy significantly affects the structure of communities and is more determinant for the occurrence of individual species than their abundance. Significant effect was also found in species diversity. Minerotrophic peat bogs have apparently higher species diversity, which is mainly determined by the...
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Ecological biomonitoring of peatlands - the NCV index, acidification and eutrophication
Henková Mauleová, Lucie ; Neustupa, Jiří (advisor) ; Šťastný, Jan (referee)
Biomonitoring is a method of ecosystem properties determination based on its biological properties, especially composition of the biota. Based on various aquatic-oriented biomonitoring systems, it is possible to quantify, for example, water purity or trophic index for water management purposes or to characterize the ecological status of the ecosystem for scientific and conservation purposes. While water quality-oriented biomonitoring systems are widespread and routinely used, ecology state-oriented (quantifying qualities like succession stage or stability) are less exploited and their wider use in the future could help understanding and management of some aquatic ecosystems. One of the ecology-oriented biomonitoring systems is NCV index (natural conservation value index) oriented to wetlands which it evaluates through their desmid biota, measuring species diversity, rarity of represented species and ecosystem maturity for which they are typical, and rarity of represented species NCV index aims to describe the value of the ecosystem in terms of its replicability.
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Diversity and distribution of the Euastrum humerosum / didelta (Desmidiales) species complex
Kupčíková, Eva ; Šťastný, Jan (advisor) ; Kollár, Jan (referee)
From 23 European and North American strains Euastrum humerosum/didelta species complex (Desmidiales) I have obtained 3 lineages in molecular marker trnGucc group II intron. I did not acquire significant and homogenous results in SSU intron. It is probable that the lineages of trnGucc intron are very young. SEM revealed one central pore in cell wall and five bulges. The lineages were significantly different in their shape and dimensions. The lineages differentiated mainly in their length and breadth of the cells. The lineages inside morphotype E. humerosum differentiated in shape and dimensions of the polar lobe. The lineages inside morphotype E.didelta differentiated in shape and dimensions of the neck. That was ascertained using the geometric morphometrics with the measuring. Linear discriminant analysis of the desmids from literature revealed that is possible to partly discriminate groups of the varieties (E. humerosum var. parallelum and E. didelta in lineage A; two formae E. didelta f. val Piora and E. didelta f. latior in lineage B; E. didelta var. inermiforme and E. humerosum var. affine in lineage C). Key words: desmids, species, hidden diversity, molecular phylogenetics, geometric morphometrics, Euastrum, scanning electron microscopy
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Biodiversity-productivity relationship in desmid communities
Škvorová, Marie ; Škaloud, Pavel (advisor) ; Nedbalová, Linda (referee)
This thesis deals with biodiversity-productivity relationship in desmid communities. Biodiversity is found to be changing globally. The biodiversity-productivity relationship is therefore an important research topic. Three aspects of biodiversity are thought to play an important role: species richness, functional diversity and phylogenetic diversity. It is known that in general, productivity is positively correlated with diversity. Interactions between different metrics of biodiversity are known less. Existing studies have shown that these interactions might be present. In general, biodiversity-productivity studies were mostly focused on plants. Less is known about other organisms, including algae. In this work I explore the relationship between overyielding and functional or phylogenetic diversity on a species richness gradient of desmid communities. I conducted an artificial biodiversity- ecosystem functioning experiment using combinations of two to 12 desmid species. Communities differed in the diversity aspects. I had measured the biomass growth. For the analysis, I have used the overyielding index, which is based on a comparison of a polyculture production with the production expected based on monoculture yields. The relationship of overyielding on functional diversity depended on species...
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Diversity and distribution of the Euastrum humerosum / didelta (Desmidiales) species complex
Kupčíková, Eva ; Šťastný, Jan (advisor) ; Kollár, Jan (referee)
From 23 European and North American strains Euastrum humerosum/didelta species complex (Desmidiales) we have obtained 3 lineages in molecular marker trnGuuc group II intron. We did not acquire significant and homogenous results in SSU intron. It is probable that the lineages are very young. The lineages were significantly different in their shape and dimensions. We used the geometric morphometrics with the measuring of the lengths and breath of the semicells, isthmus and their ratios. The lineages differentiated in their dimensions and shape variable polar lobes and neck. SEM revealed the one central pore in cell wall on the contrary, with variant E. didelta var. bengalicum, which has two pores according the literature records. Key words: desmids, species, hidden diversity, molecular phylogenetics, geometric morphometrics, Euastrum, scanning electron microscopy
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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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Diversity of the Micrasterias papillifera / M. radiosa (Desmidiales) species complex
Trumhová, Kateřina ; Šťastný, Jan (advisor) ; Mareš, Jan (referee)
This Master's thesis deals with diversity within the Micrasterias papillifera/ M. radiosa (Desmidiales) species complex. Both species are inhabitants of endangered biotops, like peat-bogs and, like other desmids, are used for biomonitoring. Many described varieties for both of them can be found in taxonomic literature, but their morphology is overlapping and revision of this species complex seemed to be necessary. All strains were isolated from peat-bogs and lakes across Europe and my dataset was properly completed by strains from algal collections. Results of phylogenetic analysis of sequences for ITS and psaA showed, that the real intraspecific diversity of Micrasterias papillifera Brébisson ex Ralfs was overestimated. Although I could find a little intraspecific diversity within the ‚papillifera' lineage in the phylogenetic tree based on ITS sequences, it did not correspond with a morphology of isolates. M. papillifera possess unexpected morphological plasticity and also some isolates designated as Micrasterias radiosa Ralfs were present in this lineage. On the contrary, there were only a few isolates in the lineage ‚radiosa'. This species seems to be relatively rare and probably has limited distribution. Both species are morphologically well delimited from each other on the basis of several characters...
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Substrate specifity of epiphytic communities of diatoms (Bacillariophyceae) and desmids (Desmidiales)
Mutinová, Petra ; Neustupa, Jiří (advisor) ; Šímová, Irena (referee)
Substrate specificity of epiphytic communities of diatoms (Bacillariophyceae) and desmids (Desmidiales) Bc. Petra Mutinová Master's thesis, Prague, 2015 Abstract It has been always assumed, and frequently reported, that host plants, as biologically active substrates, should have a direct influence on associated epiphyton. However, some studies favoured the neutral substrate hypothesis. Thus the relationship between host plant and epiphytic community remained unresolved. This Master's thesis focused on the basal question that numerous previous studies overlooked. Is there any significant influence of host plant on freshwater algal epiphyton in comparison to the influence of other factors, e.g. site and environmental conditions? In addition, substrate specificity of individual algal taxa was investigated. The research concerned several types of natural plant substrates at several water bodies in the Czech Republic, which provided a more accurate and general insight in the ecology of microphytobenthos. The results have demonstrated that site was the main factor affecting epiphytic community structure, followed by mild, but still noticeable, effect of environmental conditions (pH and conductivity). In contrary, host plant had almost no influence and very few algal species were found to be host specific....
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Cryptic and pseudocryptic diversity of conjugating green algae (Zygnematophyceae)
Kupčíková, Eva ; Šťastný, Jan (advisor) ; Škaloud, Pavel (referee)
This bachelor thesis summarizes the most commonly used species concepts in the class Zygnematophyceae. This group of algae and the molecular markers used in the zygnematophytes' molecular phylogeny will be presented in this thesis. Zygnematophytes have unicellular or multicellular forms and they generally occur in freshwater habitats. Desmids are useful as indicators of water quality and they are also used for scoring of conservation value. Therefore it is important to have the species well defined. The confusion in defining of desmid species was caused by often very variable morphology. Some authors had different opinions on the classifying of desmid species and theirs subunits. The combination of molecular phylogeny, electron microscopy and geometric morphometrics was used in revealing of (pseudo)cryptic species in the genera Micrasterias or Xanthidium. The geometic morphometrics was helpful for finding of important details for distinguishing of particular pseudocryptic species. Key words: cryptic and pseudocryptic diversity, conjugation, desmids, Micrasterias, Euastrum, Xanthidium, molecular phylogeny, taxonomy, geometric morphometrics, biogeography, green algae
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