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Ombrotrophy and minerotrophy of acidic wetlands - ecological and environmental indicators
Hanousková, Andrea ; Neustupa, Jiří (advisor) ; Šťastný, Jan (referee)
In this thesis I focus on different aspects of two basic types of peatlands - ombrotrophic bogs and minerotrophic fens, that differ in the source of their water supplies. In case of the bogs, all the moisture comes from precipitation, the fens are in varying degrees supplied with water from the mineral soil and bedrock. This concept is based on the assumption that hydrological conditions are essential for other properties of acidic wetlands, especially for vegetation, which is still the subject of discussion. Therefore I mention different gradients of peatlands (pH, nutrients and minerals) and important processes (succession, accumulation of peat) with regard to their relation to minerotrophy and ombrotrophy and I discuss their importance for the entire ecosystem. In the second part of my thesis, I focus on the algal assemblages in peatlands, which despite its immense diversity often form a neglected component of these ecosystems. The structure of algal communities vary in space and time under the influence of various factors, including, among others, ombrotrophy and minerotrophy. Powered by TCPDF (www.tcpdf.org)
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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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Associations of fish with various types of littoral habitats in reservoirs
ŠMEJKAL, Marek
The study investigated fish habitat association within littoral habitat of four Czech reservoirs. Three most common habitats within reservoir: beaches (former meadows), stump fields (former forest) and rubble slopes were chosen for the study. The patterns of fish biomass, abundance and species structure were analysed based on robust data obtained from gillnet sampling. Adult bream Abramis brama, white bream Blicca bjoerkna and roach Rutilus rutilus were associated with beaches and stump fields with gentle slope of the bank, whereas perch Perca fluviatilis, ruffe Gymnocephalus cernuus, asp Leuciscus aspius and pike Esox lucius were associated with rubble slopes. We demonstrated fish species are not distributed homogeneously in the littoral and that that most common species are associated with distinct habitats.
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The importance of woodlots for birds in farmland
Rajmonová, Lenka ; Reif, Jiří (advisor) ; Zasadil, Petr (referee)
One of the outcomes of agricultural intensification is landscape homogenization, particularly obvious in developed countries. Unproductive plots of woody vegetation may represent a refuge for many species within large blocks of open areas. Eventhough it is crucial to assess the importance of such plots for animals in farmland, surprisingly, no synthesis on this topic has been published up to now. Therefore, performance of such an assessment is the main task of this bachelor thesis which is focused on birds since they heavily suffer from agricultural intensification. It was found that marginal vegetation provides not only habitat for breeding and foraging but also ecological corridor for birds᾽ short-distance movement and stopover sites for long-distance migrants. The structure of avian community is affected by specific characteristics of vegetation itself considerably and also by characteristics of landscape in smaller measure. Both farmland and forest birds occur in marginal vegetation, each of these bird groups utilizes these plots in a different way based on its ecological needs, however. The understanding of these mechanisms will allow effective conservation of biodiversity and restoration of once devastated areas. The main goal of conservation should be to ensure heterogeneous landscape mosaic...
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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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Ombrotrophy and minerotrophy of acidic wetlands - ecological and environmental indicators
Hanousková, Andrea ; Neustupa, Jiří (advisor) ; Šťastný, Jan (referee)
In this thesis I focus on different aspects of two basic types of peatlands - ombrotrophic bogs and minerotrophic fens, that differ in the source of their water supplies. In case of the bogs, all the moisture comes from precipitation, the fens are in varying degrees supplied with water from the mineral soil and bedrock. This concept is based on the assumption that hydrological conditions are essential for other properties of acidic wetlands, especially for vegetation, which is still the subject of discussion. Therefore I mention different gradients of peatlands (pH, nutrients and minerals) and important processes (succession, accumulation of peat) with regard to their relation to minerotrophy and ombrotrophy and I discuss their importance for the entire ecosystem. In the second part of my thesis, I focus on the algal assemblages in peatlands, which despite its immense diversity often form a neglected component of these ecosystems. The structure of algal communities vary in space and time under the influence of various factors, including, among others, ombrotrophy and minerotrophy. Powered by TCPDF (www.tcpdf.org)
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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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Community structure of soil saprophagous mites and their food selection
Jourová, Barbora ; Smrž, Jaroslav (advisor) ; Hubert, Jan (referee)
Community structure of soil saprophagous mites illustrates not only their diversity, but also it is able to characterize biotop as a whole. Such structure can be correlated with fluctuation of factors in with respect to the historical development and perspectives of biotope. Therefore, community structure exhibits the dynamics. The nutritional biology belongs to biological as well as to ecological parameters. This work presents the summary of existing knowledge about study of nutritional bi- ology and community structure of soil saprophagous mites and also critical analysis of methods studying soil mites. Keywords: moss mites, community strukture, food selection.
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The importance of various types of littoral habitats for fish in reservoirs
ŠMEJKAL, Marek
The aim of this study was to evaluate fish habitat preferences in three various types of littoral habitats (beaches, rubble slopes and stumps). Data originated from four Czech canyon-shaped reservoirs. This study showed that habitats differed in biomass and abundance of fish as well as in species compositions. Patterns in biomass, abundance and species preferences were the same even under different community structures of sampled reservoirs.
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