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Long term dynamic of vegetation succession on post-mining sites.
Skalníková, Andrea ; Mudrák, Ondřej (advisor) ; Janíková, Eva (referee)
Spontaneous succession of vegetation can be one of the restoration approaches of disturbed sites after coal mining. It is therefore important to know the course of successional changes and whether it can be replicated. The spontaneous succession of vegetation on disturbed sites is usually based on monitoring of multiple sites of a different stage of succession. By their comparison the course of the succession over time is inferred. This approach of the study is called chronosequence (space-for-time substitution). Another option is to repeat monitoring of permanent plots, but it requires a long period of time to observe successional changes. Rarely are these approaches combined. In this thesis, I analyse the main trends in the succession of plant communities and their plants functional traits on five localities of various age during the 15 years. I have examined whether the localities follow similar successional trends. Data (plant coverage) were collected by annual resampling of 50 (ten per locality) permanent plots of 5 m x 5 m since 2007. By performing a multivariate CCA analysis, we analysed the species composition of the plant community, and by performing an RDA analysis, we analysed the changes in weighted averages of plant functional traits. In both cases, the localities and their...
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The relationships among functional traits of tardigrades (Tardigrada), their diet, and environmental conditions
TŮMOVÁ, Michala
In this thesis, I explore several ways how to use functional traits to study the tardigrade role in the soil food web. The goal of the thesis was to show that it is possible to study tardigrade ecology even without species identification. Trophic classification of tardigrades, as well as morphometric traits of each individual, were used as functional traits. First, I confirmed the existence of different trophic groups, testing the whole spectrum of potential diet in three tardigrade species from different trophic groups. I showed that tardigrades differed not only in the scope of ingested items but also in survival and fecundity under different types of diet. Secondly, I compared trophic group composition with species composition in natural tardigrade communities. The results showed that species, as well as trophic group composition, responded to the same environmental drivers. Trophic group composition enabled easier interpretation of the tardigrade role in the soil food web, while species composition illustrated also species-specific preferences that were not connected to their feeding habits such as preferences for different levels of soil moisture. Finally, I have used morphometric traits measured in each individual separately which allowed me for evaluation of inter-specific as well as intra-specific variation. As a result, buccal tube length was selected as a predictor of tardigrade feeding preferences among nematode, rotifer, and tardigrade prey. In summary, the thesis documented that functional traits provide a tool for the prediction of tardigrade feeding behaviour and detection of changes in the role of tardigrades along environmental gradients without the need of species identification.
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The efficiency of pollen transfer by selected functional groups of pollinators and the ability of plants to influence it
Freudenfeld, Martin ; Janovský, Zdeněk (advisor) ; Klečka, Jan (referee)
Pollinator functional groups differ in their pollen carryover effectiveness and in the importance for particular species of plants, due to specific functional traits of pollinator functional groups. Plant species differ in their specific functional traits too. I determined pollen loads of pollinators by swabbing their bodies with a jelly to compare pollen carryover effectiveness of pollinator functional groups. This helped me to decide which pollinator functional groups are the most and the least effective in pollen carryover. I considered an influence of the last visited flower to make the comparison of pollen loads more accurate. I also calculated proportions of conspecific and heterospecific pollen grains carried on bodies of pollinators to estimate their carryover effectiveness. Likewise, I compared composition of pollen morphotypes carried on pollinator's bodies to find out differences among pollinator functional groups. My analysis shows that pollen carryover effectiveness of particular pollinator functional groups differ. Apis mellifera and solitary bees have the biggest pollen loads, on the other hand, butterfies and small dipterans have the smallest pollen loads. The last visited flower influences an amount of pollen grains carried on bodies of pollinators. Relative pollen loads of some...
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Pollinator pollen carryover effectiveness and plants' ability to enhance it
Freudenfeld, Martin ; Janovský, Zdeněk (advisor) ; Mikát, Michael (referee)
Pollinators carry over pollen from one flower to another. They facilitate plant reproduction. Pollinator functional groups differ in their effectiveness of pollen carryover. Quantity of pollen grains on their body and deposition on stigma are very important. Pollinator carryover capacity depends on its functional traits. Body size, hairiness, visitation behaviour, foraging preferences, flower constancy and abundance of pollinators are significant. Plants can enhance effectiveness of their pollination by adaptations to specific pollinator functional groups. They improve positioning of pollen on pollinators by specific changes to floral morphology, quantity and size of pollen grains. They can also enhance the effectiveness through aggregation of pollen grains into groups or into pollinia or by optimisation of pollen release in time.
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Technologické vlastnosti křepelčích vajec
Dostálová, Marie
Technological properties, in other words functional properties, of quail eggs influence the preparation and production of food. The basic functional properties of egg albumen include gel formation, foam formation and suppression of crystallization. Gel formation is important in the production of boiled quail eggs. Foam formation is necessary in the production of confectionery and bakery products. Suppression of crystallization is used especially for confectionery. The functional properties of egg yolk can include the emulsion formation and antioxidant action of the phospholipids of yolk. Emulsion formation is important in mayonnaise production. For certain technological properties, there are defined criteria, which describes applicability and quality of eggs. Foam ex-pansion index, foam stability index, foam density and toughness are obtained during the foam formation of quail fresh or dried albumen. Emulsion stability index and emulsion activity index are obtained during formation of emulsion from quail fresh or dried yolk. Functional properties are influence affected for example by solubility of protein, water-holding and oil-holding capacity.
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Evaluation of functional properties of selected vegetable flours
VÍTKOVÁ, Věra
This bachelor thesis deals with basic structure, nutritional properties, production and use of flours. There are information about cereals and legumes, which are used for productions of flours. This thesis talks about food intolerances, which can be a reason why change basic flours of wheat, barley, oat and rye to another. Practical part is about 14 flours, which were tested on dry matter, humidity, nitrogen substances content, proteins, protein electrophoretic profiles (patterns), solubility, water and fat holding capacity, formation of gels and changes of colours during a boiling. The results of this research are information about nutrition and functional properties of tested flours.
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How universal are reserve design rules? A test using butterflies and their life history traits
BARTOŇOVÁ, Alena
This thesis uses butterfly species lists for 125 Czech National Nature Reserves and Monuments to test the validity of generally agreed 'reserve design rules' using multivariate ordination analyses. We used analyses of butterfly life history traits to seek for biological mechanisms responsible for butterfly community responses to geometric and heterogeneity characteristics of the reserves. We found that different design characteristics are important for individual species, depending on their life histories.
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