|
|
Biotopes associated with migration corridor valley of the Tichá Orlice river (Eastern Bohemia, Czech Republic)
Rejzek, Tomáš ; Kovář, Pavel (advisor) ; Černý, Tomáš (referee)
Biotopes associated with railway corridor in valley of the river Tichá Orlice (Eastern Bohemia, Czech Republic) ABSTRACT Expansion, invasion or decline of plant species caused by environmental changes belong to the most important phenomenons associated with vegetation cover development. In spite of their often initiation by human activities the above mentioned processes continue then spontaneously and uncontrollably. This study is concentrated to the effect of these mechanisms on the biotope structure along the Tichá Orlice River (Eastern Bohemia, Czech Republic) - in its lowland landscape segment of the canyon character where the second axis of the valley (river flow is the first one) is created by railway line more than 150 years of local history. The case study has the general aim: to treat the present and/or future impact of described trends to plant biota and the degree of its influencing. My diploma thesis investigates functional impact and mutual interaction of the two main migration pathways of exotic species - the T.Orlice river and the railway corridor. It presents qualitative and quantitative changes in plant components of local (semi)natural biotopes by mean of interrelationships among selected ecological groups of species (neophytes, expansive species, and ephemeroids). At the same time, this...
|
|
|
Hydraulic cylinder
Černý, Tomáš ; Kozák, Jiří (referee) ; Klas, Roman (advisor)
Bachelor thesis contains a brief description of the principle of operation of hydraulic motors, their use and computational relations. The main part of the research is devoted to hydraulic cylinders, their principle of function, division and construction. Also, a space for calculating the buckling stiffness of the piston rod is given. The next part deals with mathematical modeling of hydraulic mechanisms. A simple mathematical model is created in the case of a hydraulic cylinder with two identical piston rods and in the case of a differential piston. Based on the model, graphs of the frequency of oscillation are plotted. The possibilities of influencing the frequency of oscillating are explained by changing the parameters of the cylinder.
|
|
|
Phytogeographical analysis of distribution of selected xero-thermophilous herbaceous taxa along the Sázava River valley in Central Bohemia
Vlasák, Tomáš ; Černý, Tomáš (advisor) ; Boublík, Karel (referee)
This study is focused on a phytogeographic analysis of the distribution of selected xero thermophilous herb taxa along the Sázava Canyon in Central Bohemia. The research was done in 62 localities scattered along the major river stretch from Ledeč nad Sázavou to the confluence of Sázava with the Vltava Riever. The Sázava River was divided according to the river mileage into 8 even sections where there were 6 or 7 larger representative localities further selected. In each locality there was obtained the semi quantitative floristic inventory of species according to a pre prepared check in list with 57 taxa, further a detailed exploration of the locality was performed including the measurement of the area (in ha), direct perpendicular distance to the Sázava riverbed (in km), distance of the locality related to the river mileage, proportion of slopes of southern expositions, by means of conservative method using paper maps, calculation of the coefficient of variation of local altitudes (i.e. the assessment of vertical complexity), reading of geographical coordinates by tourist GPS receiver and finally a detailed determination of bedrock types at individual localities. The results were processed and then statistically evaluated in the program CANOCO software for multivariate analyses. The CANOCO program calculated that the influence of species composition in the given areas describes approximately 8.6 % of the total variability of individual species. This influence is proven to be statistically significant on the alpha level = 5%. The analysis, using observed data, calculated that 28.9 % of total variability of the vegetation composition in the studied floristic areas is influenced by the chosen variables. This work may serve as a comprehensive resource of the sites for future research, also it brings a valuable floristic data for the nature conservation purposes.
|
|
|
Correlation analysis among the distribution of forest vegetation zones, selected climatological parameters and actual vegetation status in Hostýn-Vsetín Mountains subregion of natural forest region 41
Pšenko, Martin ; Černý, Tomáš (advisor) ; Ulbrichová, Iva (referee)
Hostýnské mountains are part of the most frequently visited forests in Moravia. Whether because of the numerous cottage and recreational areas with abundant occurrence of fungi, these forests were subject to great anthropogenic influence since its origin. Therefore, it was created on the territory of several protected areas and nature reserves, which were designed to preserve the natural vegetation potential of local vegetation and protection of rare species of local phytomass and zoomass. The goal of this thesis is the verification of the respective forest vegetation zones of the investigated plots, which had been historically assigned in several respects. In the past, namely the allocation of forest vegetation zone was entirely an empirical matter, which scientists have not been able to verify the correctness of his judgment by means of statistical analysis, as is the case nowadays. The plots were therefore selected to characterize best the local conditions, whether in terms of species composition of vegetation or climatic conditions. On the 20 selected plots there were collected data within individual tree layers (based on Kraft-Zlatník scale), species composition and level of development of individual trees by circuits measured at breast height and height measurements according to average individuals. As additional data for the overall evaluation were used climatological maps using GIS software creating a mosaics from which it can be acknowledged how much of the forest stands is affected by abiotic factors such as the length of the snow or the average air temperature. The data assembling the complete image of the plot characteristics were subsequently analysed by regression and multivariete statistical analysis. The obtained results show the context between the actual stage of the forest stands and the used climatic parameters. I believe that this work could be a model for those who do not rely on empiricallly-derived forestry maps and admit that the overall climate in our country is changing and evolving. It is therefore important to consider these causes not only for the purposes of forest management, but also for the protection of existing vegetation.
|
|
|
Influence of understory light on diversity and composition of forest vegetation in the České Středohoří Mts.
Macek, Martin ; Kopecký, Martin (advisor) ; Černý, Tomáš (referee)
Light is essential component of forest ecosystem, as limited light availability in forest-floor restricts herb and tree seedlings growth. Importance of light availability for maintaining plant species diversity and community structure wasn't sufficiently evaluated in the Czech Republic. This study focus on the ecological relevance of light availability on both landscape and local scale. Relationship of light to cover, diversity and species composition was quantified in the thesis. Dominant tree species affected light availability and its spatial variability. Light availability was along the soil reaction and slope most influential factor for large-scale species diversity. Within-site light variability affected plant diversity more than soil reaction variability. Measuring light by means of hemispherical photography seems to be an appropriate for studies like this. Light availability influnence on community compostition is weak in comparison with other environmental gradients.
|
|
| |
|
| |
|
| |
|
| |
|
|
Vascular plants along the roads in the Jizerské hory Mts – the effect of altitude and contact habitat
Titěra, Jan ; Boublík, Karel (advisor) ; Černý, Tomáš (referee)
The aim of the diploma thesis was to map the incidence of vascular plants along the various categories of roads and crossroads at different altitudes and in different contact habitats (forests × meadow) and identify invasive species. The species were mapped to a total of 120 sites, including 45 sites accounted for forest roads, 40 sites meadow paths and 35 sites forest crossroads. There were found 3 strongly endangered species and 5 endangered species. From the total non-native species was found a large proportion of naturalized and invasive species that could potentially threaten natural communities. DCCA analysis was found that the species composition invasive plant reacts to the individually environmental variables statistically significant. It was also found large share of competitive strategies, and a small share of stress-tolerant strategists. Furthermore, it was found that the species composition of the flora responds to altitude statistically highly significant. DCA analysis was found affiliation species to categories of roads and crossroads, level of traffic and to contact habitats. Furthermore was used CCA analysis. It was found that the species composition of the plant reacts to the presence of trees present in the surrounding vegetation statistically highly significant. Part of the work has also been gathering literature data about the relationship between flora and roads, vectors of spread plants and alien species and flora of roads in Jizera mountains. The results were compared with other works, and complemented by own knowledge of the author, in the discussion. Contribution of work consists in mapping the flora of roads and crossroads in many locations in Jizera mountains, botanical supplement data and the identification of potentially invasive species expanding along the roads. The results of this study should serve as a basis for preventive or protectionist measures implemented in Jizera mountains.
|
guest ::
RSS feed.