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Vliv antropogenních aktivit na společenstva vodních organismů v horní části povodí Litavky
ČERNÝ, Jan
The degradation of the natural environment is considered to be a global problem. Due to the importance of water sources, preservation and improvement of their quality are one of priority interest of all society. This study deals with the reactions of aquatic organism groups like fish and benthic invertebrates to an anthropological effect in the Litavka basin. Researched part of Litavka is polluted by toxic heavy metals from past ceveral centuries of extensive mining and industrial smelting in its close proximity. It is also polluted by releasing wastewaters, which contain xenobiotics, trash, and decomposing organic matter. The Obecnický stream was chosen as a reference locality because it is the most similar to a clear natural habitat. It flows into the Litavka river in a spot, where the riverbed is channelised and its floodplain is occupied by toxic waste dumps. The Obecnický stream can be considered the most important water source in the upper Litavka basin regarding the current hydrological conditions. Autochthonous fish population in the upper Litavka basin suffer from several water abstractions, which change temperature and flow regimes. It was our effort, to evaluate the influences of these anthropological factors on aquatic biota, aiming to above-mentioned pollution types, and presence of the water reservoir situated on the Obecnický stream. Monitoring of organism and environmental data collecting (physically chemical parameters, NH4+ , NO2-, PO43-, bottom substrate, flow, and others) were always implemented parallelly. In the case of fish species groups, the resulting correlations show us the greatest impact of the temperature gradient and zinc concentration. We found out a negative correlation between zinc concentrations and abundances of brown trout (Salmo trutta morpha fario) and brook lamprey (Lampetra planeri). On the other hand, common minnow (Phoxinus phoxinus) was highly tolerant for this kind of pollution. The abundance of brown trouts decreased with increasing temperature and it seemed as beneficial for common minnow populations. There was also a shift in the community of invertebrates, namely total absence of three mayflies families (Ephemerellidae, Heptageniidae and Leptophlebidae), Gammaridae, the sphaerid clam Pisidium sp. and the river limpet (Ancylus fluviatilis). The inflow of the wastewaters was accompanied with considerable increase of biomass of common several cyprind species. Besides that, there was a high density of eruciform caddisflies of genus Micropterna and Halesus. Within particular benthic invertebrates, domination of dipteran insects, leeches (Hirudinea) and the freshwater waterlouse (Asellus aquaticus) was observed under the outcome of wastewaters.
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The influence of management on biodiversity of vertebrates model groups - small mammals
KOUTNÍKOVÁ, Lenka
This bachelor{\crq}s work: The influence of management on biodiversity of vertebrates model groups {--} small mammals, creates a part of a large study focused on an assessment of influence of different agricultural management on ecological functions and water fluxes in the landscape of spring water areas in Bohemian forest. The bachelor{\crq}s work is based on a hypothesis that management influences among others also biodiversity of the locality. Small terrestrial mammals are one of the vertebrate groups, which diversity is a good indicator for momentary quality of environment. It is given by their good reproduction capacity and ability of invasion. The aim of this work is to compare the small mammals{\crq} biodiversity of three small catchments with different management. The theoretical part contains literary review of the small mammals{\crq} occurrence in Bohemian forest, their microhabitat preferences and the influence of management on their communities diversity. In the practical part, data from three live-trappings realized during the summer and autumn 2007 were evaluated. The greatest diversity and abundance of small mammals were recorded in the forested catchment of Bukový potok. By contrast, we captured no individual of small mammal in the drained Mlýnský potok catchment, which is used as a pasture. The theme was supported by a project MSM 6007665806.
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Microclimate as a driver of species distribution and community composition of bryophytes compared with lichens
Růžičková, Anna ; Man, Matěj (advisor) ; Starosta, Jakub (referee)
This bachelor thesis deals with the influence of microclimate on species distribution and composition of bryophyte and lichen communities. It defines the term microclimate, characterizes the specific properties of bryophytes responsible for their sensitivity to microclimatic conditions and includes a comparison of the role of individual microclimatic factors in controlling the distribution of bryophytes and lichens. The key microclimatic factors for bryophytes are humidity and air temperature, but the significance of each varies between functional groups of species and depending on the type of biome. With the available portable measuring devices with large battery capacity and memory storage, it is now possible to measure in-situ microclimate for the long-term and also with high spatial and temporal resolution. Despite that, there are currently only 12 bryological studies that provide continuously measured field microclimatic data on small spatial scales. The main part of the thesis summarizes these studies and compares the methodologies used. The paper can serve as a starting material for designing bryological microclimatic studies.
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The relationships between diversity patterns and community abundance
Dlouhá, Hana ; Storch, David (advisor) ; Keil, Petr (referee)
Increase in the number of species with area is one of the most studied ecological patterns. There is a considerable amount of literature devoted to this question. The rate of increase in the species diversity with area isn't equal at all the spatial scales, as shown by empirical studies. On the finest and coarsest scales, there is distinctively higher rate of increase than on the middle (regional) scales. These distinctions were attributed to many characteristics of environment, taxon etc. There is a possibility to explain the variability of this particular rate by mean species abundance. This work focuses on summarizing the relationships between the rate of increase in biodiversity with area, factors that influence it and mean species abundance.
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Life history strategies of arbuscular mycorrhizal fungi
Fričová, Renata ; Janoušková, Martina (advisor) ; Kohout, Petr (referee)
Arbuscular mycorrhiza is a symbiotic interaction of vascular plants and arbuscular mycorrhizal (AM) fungi from subphylum Glomeromycotina. Currently, it is difficult to predict the population dynamics of AM fungal communities, mainly because little is known about their life-history strategies. However, it is clear that AM fungi differ in a range of traits. Physiological and ecological differences between AM fungi can affect the outcome of their competition as well as cooperation with the plant symbiont and the successional dynamics of the whole community. In order to advance our knowledge of AM fungal life-history strategies, it is crucial to deepen our understanding of the traits and factors that modify interactions between the symbionts. This bachelor thesis is designed as a literature survey aimed at summarizing knowledge about functional traits of AM fungi and the impact of these traits on their life-history strategies. Key words: arbuscular mycorrhizal fungi, life-history strategies, host plant, traits, mycelium, colonization, competition, community, succession
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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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Microclimate as a driver of species distribution and community composition of bryophytes compared with lichens
Růžičková, Anna ; Man, Matěj (advisor) ; Starosta, Jakub (referee)
This bachelor thesis deals with the influence of microclimate on species distribution and composition of bryophyte and lichen communities. It defines the term microclimate, characterizes the specific properties of bryophytes responsible for their sensitivity to microclimatic conditions and includes a comparison of the role of individual microclimatic factors in controlling the distribution of bryophytes and lichens. The key microclimatic factors for bryophytes are humidity and air temperature, but the significance of each varies between functional groups of species and depending on the type of biome. With the available portable measuring devices with large battery capacity and memory storage, it is now possible to measure in-situ microclimate for the long-term and also with high spatial and temporal resolution. Despite that, there are currently only 12 bryological studies that provide continuously measured field microclimatic data on small spatial scales. The main part of the thesis summarizes these studies and compares the methodologies used. The paper can serve as a starting material for designing bryological microclimatic studies.
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Revision and evaluation of sites with current and historical occurrence of selected species \kur{Orchidaceae} in Bohemian Paradise (Czech: Český ráj)
ALBRECHTOVÁ, Linda
The subject of this diploma thesis was the research of vegetation at localities in the Protected Landscape Area Bohemian Paradise. There were choosen areas: Natural Monument Podloučky and Protected Area Fialník, where grows an orchid Gymnadenia conopsea subsp. montana. There were made 60 phytocenological samples, and described: biotop, altitude, slope, huminidy and exposure. There were found four orchid species in the localities. Phytocenological samples were compared with each other. It has been shown that differences between localities are greater than the differences between orchid and non-orchid samples. Significant differences were also found in comparing the coverage in the floor between locations and abundace of species in each floor.
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The relationships between diversity patterns and community abundance
Dlouhá, Hana ; Storch, David (advisor) ; Keil, Petr (referee)
Increase in the number of species with area is one of the most studied ecological patterns. There is a considerable amount of literature devoted to this question. The rate of increase in the species diversity with area isn't equal at all the spatial scales, as shown by empirical studies. On the finest and coarsest scales, there is distinctively higher rate of increase than on the middle (regional) scales. These distinctions were attributed to many characteristics of environment, taxon etc. There is a possibility to explain the variability of this particular rate by mean species abundance. This work focuses on summarizing the relationships between the rate of increase in biodiversity with area, factors that influence it and mean species abundance.
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