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Causes of vegetation heterogeneity of oak forests in Podbořansko region
Procházka, Michal ; Vojta, Jaroslav (advisor) ; Melichar, Vladimír (referee)
Thermophilous oak forests are a habitat characterized by a large diversity of vascular plants. In the case of open canopy woodlands, the diversity of the herb undergrowth is enhanced by the significant heterogeneity of the environment. It can be demonstrated for example at the Dětaň Chlum in neighborhood of the Doupovské hory Mts. However, it has not yet been fully known which natural characteristic have the most significant influence on the formation of such a diverse vegetation. One of the possible causes can be found in historical management. Therefore, this work provides some insight into the history of forest management in the Podbořany region based on archival materials such as Historical Forest Survey, Management Plans or Archive Maps. The obtained information is to a large extent surprising. It has been shown that coniferous stands with a long time of timber extraction have dominated the Dětaň chlum in the past. However, this contradicts the assumption that it is an ancient oak coppice, as suggested by the current appearance of vegetation with a high incidence of polycormones in the local nature reserve. To find out the environmental causes of the current heterogeneity of vegetation, I used the CANOCO statistical program to analyze the dependence of my own phytosociological data on selected...
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Functional parameters of biocorridors built in fragmented cultural landscapes due to facilitation of the organism's mobility
Vaškovský, Adam ; Kovář, Pavel (advisor) ; Vojta, Jaroslav (referee)
Human caused landscape fragmentation, accompanied by loss of habitat connectivity, is currently a significant global threat to biodiversity conservation. One possible way to address this problem is to identify, establish and maintain wildlife corridors that connect isolated habitat patches to allow the movement and spread of organisms through the environment. This study based on literature review addresses the identification of relevant factors supporting functionality of wildlife corridors in various scale levels for different species or groups of organisms. Key words: biocorridor, ecoduct, barrier, landscape fragmentation, connectivity, dispersal of organisms, mobility, corridor functionality, landscape ecology
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Diversity and succession of spontaneous vegetation in urban environment
Rejchrtová, Lucie ; Vojta, Jaroslav (advisor) ; Adámek, Martin (referee)
Urban vegetation is important due to its functions (e.g. aesthetic, spiritual, recreational, hygienic). In the city, vegetation and its succession are influenced by factors such as nature in the same or altered form. Compared to the surrounding landscape, the city's climate is warmer, the urban soil has an increased pH, it is drier, it can contain more nutrients, heavy metals and salt. In the city, human activity, and humans themselves are the main plant breeder and biotope disturbant. As a result of all the above, plants with higher demands on heat, light, alkalinity, nutrients and disturbances occur in the city. These are often alien species, which are much more in the city than in the surrounding landscape due to the more frequent occurrence of early successional stages. The proportion of alien species during succession decreases in favor of the native species. The total number of species (even within each group of species - native species, archeophytes and neophytes) is higher than in the surrounding landscape due to the high diversity of biotopes and the introduction (intentional and unintentional) of species by human activity. Keywords: urban vegetation, succession, diversity, anthropogenic factors, alien species
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