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Floristicko-ekologická studie sinic a řas v různých typech stojatých vod na severním Plzeňsku
ČECHUROVÁ, Markéta
The algological research was realized on 10 various water bodies in the northern Pilsen region during the year 2020. They were mainly post-mining sites or artificial ponds, where plankton samples were collected. Environmental characteristics (pH, conductivity, water transparency, temperature, amount of nutrients) were measured. Cyanobacteria and algae found in samples were identified to the possible lowest taxonomic level, also relative abundance levels were stated. The relationship between environment and the species composition was studied. A total of 77 phytoplankton species were recorded.
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Species traits determining species composition on abandoned fields
Jarošíková, Cecílie ; Münzbergová, Zuzana (advisor) ; Klimešová, Jitka (referee)
Though succession is a widely studied process, there are only a few reports dealing with changes in plant functional types in the course of succession. Even fewer studies are dealing with agricultural, wet meadows, which are under continuous impact of mowing. The aim of this work is to fill this gap. The studied area is situated in south part of CHKO Slavkovský Les (region of Karlovy Vary, West Bohemia). In previous works grasslands on arable field after 15, 35 and 55 years after abandoned and continual grasslands in last 100 years were detected from historical agriculture maps. The releves on all types of grassland were made and the species pool was investigated. I this work I investigate the functional types and live-history traits of these species and I also look for Ellenberger values and changes of abiotic environment. The result suggests that the late - successional species are long-lived and have slower live cycle (they mature later). Their seeds are less persistent and have worse dispersal ability. Their seedlings are more viable and the species invest more to aboveground biomass than to underground. Late-successional species also flower earlier and shorter time, what seems to be an adaptation to mowing. I found no relationship between successional age in which the species occur and seed mass,...
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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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Forest vegetation changes in the Bohemian Forest during the second half of 20th century
Prach, Jindřich ; Kopecký, Martin (advisor) ; Sádlo, Jiří (referee)
Long-term forest vegetation changes were studied in the Bohemian Forest and its foothills. New vegetation relevés were taken at sites of typological plots established by forest engineers between 1955 and 1980. Data from 158 semi-permanent plots were analysed using modern statistical methods. The data show significant changes and homogenization of the vegetation. Ellenberg indicator values indicate eutrofication. Repeated measurements of soil pH suggest acidification, but the interpretation of these data is complicated by methodological problems. The forests under study exhibit high spatial variability. No main prevailing trend in vegetation changes was found. The changes are considered to be related to sulphur and nitrogen deposition and forest management. The influence of increasing age of forest stands seems to be unimportant. Discussed are not only vegetation changes and their possible causes but also the possibilities and limitations of using such old forestry data in botanical and ecological studies.
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Forest vegetation in Eastern Elbe Basin in the mid-20th century and today
Pospíšková, Marie ; Hédl, Radim (advisor) ; Novák, Jan (referee)
This thesis describes the shift in vegetation of broadleaf forests in eastern part of the Elbe River Basin between 1958-1968 and 2011-2013. It emphasizes the understorey vegetation. From lowland woodlands in other temperate regions in Europe and North America changes towards eutrophic and mesophytic vegetation are documented, specifically driven by changes in forest management and by atmospheric depositions; in some localities the game impact can be also important. The data were obtained by sampling 190 typological semi-permanent plots, which were precisely located - in 43% the original soil pit was found. The vegetation on study sites shifted towards nutrient-demanding, shade- adapted species, it was partly ruderalized. These changes can be seen on the level of species and communities as well as on phytosociological level. Increase of soil pH and moisture was discovered using Ellenberg indicator values. The number of seedlings and cover of shrubs also increased significantly. Homogenization of sites was significant as well although total number of species and alpha- diversity remained unchanged. These changes are probably caused by changes in forest management and by atmospheric depositions of nitrogen. On subset of plots in game-preserves the vegetation also demonstrated eutrophication but no increase in...
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Diversity of zooplankton of Tatras lakes in space and time
Čablová, Radka ; Černý, Martin (advisor) ; Šorf, Michal (referee)
This thesis is the first of its kind that evaluates the species composition, species richness and species abundance of zooplankton in littoral samples of 90 Tatras lakes (Western and High Tatras of Slovakia and Poland) collected in September 2004 in the context of environmental parameters of lakes and spatial relationships of individual lakes. The most frequently occurring species in the Tatras lakes in 2004 were also evaluated in terms of their occurrence in the lakes a century ago (Minkiewicz 1914, 1917 and Lityński 1913, 1917), during the period of acidification (Ertl & Vranovský 1964, Ertl et al. 1965, Hrbáček et al. 1974, Stuchlík et al. 1985) and during the period of recovery of the lakes from acidification (Hořická et al. 2006, Sacherová et al. 2006). Relationships between variables were analysed using Poisson regression, cluster analysis with multinomial regression, canonical correspondence analysis, Mantel tests and multiple negative binomial regression. Using analyses, lakes were divided into four clusters (A, B, C, D). Each cluster consisted of lakes with the same environmental and spatial factors and similar species composition. Thirteen zooplankton species (Acanthocyclops vernalis, Acroperus harpae, Alona affinis, Arctodiaptomus alpinus, Ceriodaphnia quadrangula, Cyclops abyssorum...
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Vliv acidifikace a vápnění na druhové složení a diverzitu bylinného patra na ekosystémové stanici Rájec
Müllerová, Iveta
The aim of this tittle was to evaluate changes in herb layer vegetation at the Rájec ecosystem station (Drahanská Uplands), where the conditions of acidification mitigation were artificially induced in the past by the application of dolomitic limestone. This research was carried out by collecting 60 phytocenological images. Subsequently, differences in species diversity, species claims on the environment using Ellenberg indicator values, species composition and changes in species frequencies within individual applications were evaluated.
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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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Effect of grazing on bryophytes diversity of dry grasslands in the PLA Český kras
TENČÍK, Aleš
Dry grassland are among the most endangered plant communities mainly due to the overgrowth of a number of localities. That is why from the beginning of the 21st century pasture with mixed herds of sheep and goats is restored on the most valuable dry grassland sites in the Bohemian Karst as the way of maintaining these habitats. Concurrently, research sites each 1x1 m in size were set up at four pastured localities, and were paired with control sites equipped with a fence for the research of grazing effect on vegetation. The main aim of this work was to evaluate the effect of grazing on the diversity of bryophytes at the forty pairs of the above-mentioned areas in three types of calcareous dry grasslands. In addition to the inventory of bryophytes, data on the most important abiotic and biotic factors of the environment were recorded on individual sites. The total number of bryophyte species found at the research sites is 46. 37 species were found at the grazing areas and the same number was at the fenced areas. Minimal differences in the number of species of grazed and unspoilt areas were also found in the comparison of individual localities. The grazing effect was shown up more significantly on species richness in the comparison of individual types of communities, especially in broad-leaved dry grassland (T3.4). There was a 40% increase in the number of species on grazing areas. The environmental factors have a positive effect on the species abundance mainly due to the higher slope of the terrain and the correlation with the larger occurrence of the stones, the smaller coverage of the herb layer and the litter. These conditions prevailed in areas with rock outcrop vegetation with Festuca pallens (T3.1), where the largest species richness of bryophytes in area was found. In the obtained data, the influence of grazing on the species composition of bryophytes on grazed and unspoilt areas was also assessed with the statistical methods and the Sörensen test of beta-diversity. The results show that grazing significantly influences the species composition towards open grassland and supports the growth of the bryophytes T3.1 plant community at the expense of the T3.4 plant community
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