National Repository of Grey Literature 11 records found  1 - 10next  jump to record: Search took 0.00 seconds. 
Bacterial life history strategies in gamma-irradiated arable soil receiving different microbial inocula
FARKOVÁ, Karolína
Soil contains an extraordinary level of microbial biodiversity that supports key ecosystem functions. Understanding how soil microbial communities assemble in agricultural ecosystems, as well as what traits they exhibit (i.e., what functions and services they mediate), is essential to better predict the consequences of biodiversity loss. This thesis analyzes the composition, diversity, and life history strategies of soil bacterial communities after the introduction of microbial communities from different sources (i.e., soil and cow excreta) into sterile soil (-irradiated). The results show that bacteria from soil and excreta successfully established in the -irradiated soil and that the bacterial composition and diversity strongly depends on the inoculation source. Analyses of selected functional traits proved that early colonizer taxa were characterized by having higher 16S rRNA copy numbers, smaller genomes and elevated motility and sporulation abilities than the original soil bacterial community. In addition, despite the soils showing similar initial physicochemical and biochemical properties, the different bacterial assemblages generated strong differences in soil properties and microbially-mediated functions. This thesis contributes to a better understanding on how the composition of microbial community is important for the microbial biodiversity in soil and in turn, how biodiversity can contribute to changes in soil fertility and bacterial activity through different life history strategies and traits.
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....
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...
Relationships between functional traits, home range sizes, and dispersal abilities in birds
Holubová, Kateřina ; Storch, David (advisor) ; Sedláček, Ondřej (referee)
Avian movements through the landscape involving dispersal and routine movements within home-range or territory are one of the basic but due to a high mobility of birds also one of the least understood processes of bird ecology, especially on the interspecific level. Not only is dispersal a fundamental mechanism of species' spreading into new areas, but also, together with home-range size, it shows the scale on which species perceive the landscape and how they can deal with habitat changes. Dispersal ability, represented by dispersal distances, is determined by a few species specific traits like body size, migratory status, wing and bill morphology, diet type, preferred habitat type or some life-history traits. On the contrary, home-range size variability is determined primarily by energetic demands of the species, given by its body size and trophic level, and by the productivity of the environment. There is a positive relationship between home-range size or territory size, respectively, and dispersal distances of birds that can be attributed to species vagility or their spatial requirements determined especially by their food preference. Nevertheless, further research mainly on interspecific level is necessary for a deeper insight into this issue.
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...
Functional diversity of flowers in alpine plant communities
Plachtová, Kateřina ; Sklenář, Petr (advisor) ; Koupilová, Klára (referee)
Alpine environment differs from other biomes with its special abiotic conditions, which may influence local plant communities. Species composition of plant communities' changes along the altitudinal gradient. So do its vegetative and generative functional traits, as well as abundance and species composition of their pollinators. This thesis mainly examines floral functional traits (morphology, color and chemical traits of flowers) and their diversity along altitudinal gradient. It attempts to find general trends that characterize altitudinal changes of these traits. Most crucial drivers are pollinators and abiotic factors of environment. Functional traits of alpine plants change in response to variation in abundance and species composition of pollinators. Since dominant pollinators in the alpine environment are Diptera, floral functional traits of local plant communities are adjusted according to their preference. However, floral functional traits are also depending on abiotic factors, which can have an opposite effect compared to biotic factors. Considering the complexity of alpine plant communities and also the complexity of the drivers, which influence them, it's extremely difficult to find unambiguous patterns to describe these changes. Nevertheless, some trends in the altitudinal changes of...
Lichen ecology in the relationship to functional diversity and genome size
Konečná, Eliška ; Malíček, Jiří (advisor) ; Palice, Zdeněk (referee)
Eliška Konečná Lichen ecology in the relationship to functional diversity and genome size Abstract This bachelor thesis in its first part summarises and characterizes lichen functional traits and sums up known relation between particular traits and ecological factors of the enviroment. Second part of the thesis focuses on question of genome measurment in general and than summarises known information about lichen genom size. In the second part there is partial focus on relation between genom size and ekology of organisms as well, which could become focus of some study in the future. Key words: functional traits, lichens, mycobiont, genome size
Vybrané aspekty vlivu bezobratlých herbivorů na složení travinného společenstva
HRUBÁ, Karolína
The first part of my thesis is focused on observation of the leaf damage by invertebrate herbivores during season. I examined how the selected traits affect the palatability of plant species. In the next project, I investigated the effect of herbivory and gaps on seedling establishment. And finally, in the last part, I studied the effect of herbivory of terrestrial gastropods on competitive relationships among selected species.
Diversity of traits of aculeatan hymonopterans in habitats with finely-grained substrate
Wofková, Gabriela ; Tropek, Robert (advisor) ; Šlancarová, Jana (referee)
Natural habitats of aculeate hymenopterans are rapidly decreasing and strictly specialized species are thus going to be endangered or extinct. However, in the last decades the conservation potential of postindustrial sites has been found. There were many endangered and nationally extinct species recorded along with the drift sand specialists. However, one unclear thing remains - on postindustrial sites there were still no recordings of species that have similar biological traits to the species that are colonizing these sites. The main target of my thesis was to find traits which make it possible for the insects to colonize postindustrial sites. A matrix of 79 traits was made to describe aculeate hymenopterans biotope preferences, phenology, morphology, biogeographical area, nest, food and life history strategies. With these traits I describe 351 species systematically collected on twenty-one localities with finely - grained substrate found in Polabi and South Bohemia. These traits were tested with weighted mean abundances on type of substrate (artificial vs. sandy) with GEE analysis and the type of locality (dumping ground of coal combustion, ore and sand sludge vs. sandpits vs. natural sand) with PCoA analysis. A phylogenetic correction was incorporated in both analyzes. My results show that on...
Relationships between functional traits, home range sizes, and dispersal abilities in birds
Holubová, Kateřina ; Storch, David (advisor) ; Sedláček, Ondřej (referee)
Avian movements through the landscape involving dispersal and routine movements within home-range or territory are one of the basic but due to a high mobility of birds also one of the least understood processes of bird ecology, especially on the interspecific level. Not only is dispersal a fundamental mechanism of species' spreading into new areas, but also, together with home-range size, it shows the scale on which species perceive the landscape and how they can deal with habitat changes. Dispersal ability, represented by dispersal distances, is determined by a few species specific traits like body size, migratory status, wing and bill morphology, diet type, preferred habitat type or some life-history traits. On the contrary, home-range size variability is determined primarily by energetic demands of the species, given by its body size and trophic level, and by the productivity of the environment. There is a positive relationship between home-range size or territory size, respectively, and dispersal distances of birds that can be attributed to species vagility or their spatial requirements determined especially by their food preference. Nevertheless, further research mainly on interspecific level is necessary for a deeper insight into this issue.

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