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Intraspecific trait variability of herbaceous plants in organic and conventional olive plantations in region at desertification risk
MIGLIORINO, Michele
This thesis is an ecological study in an agricultural context (agroecological research). It is carried out in olive plantations in south Italy, Apulia, a region at strong desertification risk. The effect of agricultural management (organic vs. conventional) is investigated on i) the herbaceous species composition ii) intraspecific trait variability of five selected herbaceous plants iii) soil conditions. Herbaceous plants are here considered as "indicators" of olive plantations' health. Studying if and how species traits and soil parameters vary with management, should reveal how olive understory grasslands are responding to increasing drought conditions and other desertification constraints. Management of grasslands and soils is critical to maintain high ecological functionality and services of olive agroecosystems.
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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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Transgenerational effects of plant biotic interactions
PUY GUTIÉRREZ, Javier
This thesis focuses on the transgenerational effects triggered by plant biotic interactions and explores their relevance on ecological and evolutionary processes. The following sections document novel results that show their important consequences on different aspects. Primarily, we established the necessary methodology to be able to explore these questions and to disentangle the mechanisms originating the transgenerational plasticity by validating a demethylation method. Then, we checked whether the biotic interactions alter the phenotype via within-generation and transgenerational plasticity, examining the magnitude and direction of the response on each specific "response traits". Lastly, the potential role of transgenerational plasticity for adaptation, species coexistence, creating biodiversity and population and ecosystem functioning is tested.
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From resource variation to habitat loss: how changing environment shapes the plant-pollinator interactions
AKTER, Asma
Annotation: Akter, A. and Klecka, J. 2020. Interactive effects of temperature, water, and nitrogen availability on the growth, floral traits, and pollination of white mustard, Sinapis alba. This was an experimental approach where Sinapis alba (white mustard), an economically beneficial crop was grown under different environmental conditions. Here, we assess how different growing conditions affected the growth of S. alba and the impact of different climate changing drivers on pollination and seed production. Akter, A., Biella, P., Klecka, J. 2017. Effects of small-scale clustering of flowers on pollinator foraging behaviour and flower visitation rate. PLoS ONE 12(11): e0187976. In this part of research, we experimentally changed the spatial structure of flower in small patches and assessed the impact on the foraging behaviour of pollinators, particularly, A. mellifera. Akter, A., Biella, P., Klecka, J. 2020. Introduction of new floral resources into plant-pollinator communities: impact on flower visitation mediated by species traits. This field-based experiment showed the impact of experimentally introduced floral resources in a plant community and how the response of the pollinator communities towards the new resources were mediated by the floral traits. Biella, P., Akter, A., Pajares, A.J.M., Federici, G., Galimberti, A., Jersáková, J., Labra, M., Mangili, F., Tommasi N. and Mangili, L. 2020. Pollination strategies of a plant in an unstable habitat: the case of the narrow-endemic toadflax Linaria tonzigii (Plantaginaceae). In this field-based research we assessed the pollination and reproduction strategies of an endemic plant, Linaria tonzigii, and the relation between the genetic variation and distribution. Akter, A., Biella, P., Batáry, P., Klecka, J. 2020. Changing pollinator communities along a disturbance gradient in the Sundarbans mangrove forest: a case study on Acanthus ilicifolius and Avicennia officinalis. Global Ecology and Conservation 24: e01282. This study was carried out in the Sundarbans mangrove forest, where we assessed the impact of human disturbances and forest loss on the plant-pollinator communities.
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Diversity of floral functional traits and its seasonal changes in alpine environment
Plachtová, Kateřina ; Sklenář, Petr (advisor) ; Janeček, Štěpán (referee)
Floral functional traits characterize flowers and mediate contact between entomogamous flowers and their pollinators. Their form depends on many biotic and abiotic factors. The floral functional traits tend to be similar in high altitudes. However, the overall diversity of the floral functional traits does not vary significantly between altitudes. On the other hand, how temporal diversity of the floral functional traits varies during the flowering season was not studied yet. And this is the focus of this thesis. The aim of this study is to examine the hypothesis, whether the diversity of the floral functional traits changes in plant communities of alpine and montane meadows during the flowering season and also between them. The alpine and montane meadows are located in the area of Luční hora in the Krkonoše National Park. Morphological and spectral characteristics of the flowers were measured on both meadows. Abundance of flowering species and their flowers were measured every three weeks during five periods of the season. Diversity of the floral functional traits was obtained, for both meadows and all the measured periods of season, by weighting the floral functional traits with the species abundances. Using multivariate analysis, differences of temporal and altitudinal diversity were studied....
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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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Pattern as a functional trait, case study on Mallomonas chrysophytes
Knotek, Petr ; Němcová, Yvonne (advisor) ; Rychtecký, Pavel (referee)
The patterns that can be admired on the surface of many living creatures are also found in many microscopic organisms outside of the macroscopic world we are familiar with. However, their significance and function are yet little understood compared to those of the macroscopic world. In diatoms (Bacillariophyceae) and coccoliths (Haptophyceae), several hypotheses have already been developed concerning the function of their patterned shells. One hypothesis considers the shell as a photonic entity that could reflect UV radiation away from the cell. Others focus more on its mechanical properties, which are among the most impressive within biological structures. Silica-scaled chrysophytes (Synurales, Stramenopiles) also possess a complex shell (or scale-case). Cells are covered with scales (about 4 µm in size) that are very regularly arranged and form a siliceous scale-case on the surface. The pattern on the scales is species-specific and has undergone gradual modification during evolution. This work aims to assess whether the patterning of siliceous scales in the order Synurales can be considered a functional trait or it is a result of neutral evolution. To test the possible photonic properties of the patterned structures, a pair of growth experiments were performed. The experimental cultures were...
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Relationship between the genome size of mycobiont and ecological strategy of lichens
Konečná, Eliška ; Malíček, Jiří (advisor) ; Vondrák, Jan (referee)
The inner organisation of organisms originates from the information contained within its DNA. In addition, the size of the genome itself may influence the function of the organism. Unlike many other groups of organisms, genome size is only known for a very limited number of lichen mycobionts. So far it has been only speculated whether there is a connection between genome size, the ecology and the traits of lichens. The goal of my thesis is to measure genome size of a sufficient amount of lichen mycobionts to be able to determine possible connection between genome size and ecology or functional traits of these lichen species. I succesfully measured the genome size of 50 lichen species using flow cytometry (FCM). I did molecular phylogenetic analysis of 141 taxa with known genome size in order to recognize the influence of phylogeny on genome size of these species. Two genes - ITS and mtSSU - were used for the phylogenetic analysis. Statistical analysis was performed using measured genome sizes, ecologicaly relevant traits of lichen species and my phylogenetic tree. I found that genome size might be connected to substrate preference, vegetative reproduction or the type of the lichens' photobiont. A correlation of genome size and life strategy - larger genome sizes connected to K-strategy, whereas smaller...
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Trait ecology of arbuscular mycorrhizal fungi
Hudáková, Zuzana ; Kohout, Petr (advisor) ; Ponert, Jan (referee)
Arbuscular mycorrhiza is a type of mutualistic symbiosis between fungi of the Glomeromycota division and the roots of vascular plants, which is the most common kind of mycorrhiza in the world. It is based on the exchange of substances, where the mycorrhizal fungus provides the plant with mineral nutrition and protection against pathogens and stress, and its plant host returns its products of assimilation. The phylogenetic classification of the division is equivocal, and we recognise two views on their categorisation into taxonomic groups, according to the morphology of their spores or by molecular methods, which is based on the rDNA sequence. The aim of the work is to characterise the influence of different taxa of the Glomeromycota division on the host based on their spores and the type of mycelium they prefer to form. This also affects the possibilities of the fungus, by which it can influence the life of the host plant. Key words: arbuscular mycorrhiza, arbuscular mycorrhizal fungi, Glomeromycota, spores, intraradical mycelium, extraradical mycelium, functional traits
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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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