|
|
Časoprostorové vzory zmlazení v přírodních temperátních lesích
Holík, Jan
Interactions among woody individuals can be mediated by natural enemies depending on the local community composition, thus contributing fundamentally to the formation of the spatio-temporal patterns of tree species in temperate forests. The effects of density and distance to neighbouring individuals are thought to influence the susceptibility of woody individuals to predation and their survival. However, how the effects of neighbouring individuals depend on, for example, the species and life stage of woody individuals, type of natural enemies and environmental conditions is poorly understood. The spatial extent of the effects of neighbouring individuals that influence the susceptibility of woody individuals to predation and their survival also remains an important question. This dissertation addresses the role of neighbourhood effects on the predation (herbivory) and survival of woody individuals at early life stages at several temperate forest sites in the Czech Republic. It compiles the findings from one experimental and three observational studies representing its main research areas. In terms of ecological theory, the area of research on woody seedling survival investigates neighbourhood effects associated with the Janzen-Connell effect (Papers 1, 2). In terms of foraging theory, the area of research on the susceptibility of woody individual to herbivory then investigates associational effects (Papers 3, 4). The dissertation evaluated variation in spatial scale and direction of neighbourhood effects on seedling survival in a lowland alluvial forest depending on seedling size, growth form and species (Paper 1). We found a negative relationship between the density of conspecific neighbours and seedling survival only at low light availability. This relationship was observed for the group of all seedling species except the most abundant Acer campestre. The next part of the dissertation examined the importance of natural enemies for the neighbourhood effects of adult trees (Paper 2). Due to vertebrates and partially insects, the survival of first-year Fagus sylvatica seedlings was lower beneath conspecific than heterospecific adults and it was also lower beneath conspecific adults than the survival of Picea abies. Conversely, the establishment of Picea abies was lower beneath heterospecific than conspecific adults, although it was eventually lower beneath conspecific adults than the establishment of Fagus sylvatica. The last part of the dissertation evaluated spatial patterns in neighbourhood effects on deer herbivory (Papers 3, 4). A positive relationship between conspecific neighbours and browsing of Fagus sylvatica seedlings was significant only at short distances up to 1.5 m. Conversely, we found that Abies alba neighbours increased browsing of Abies alba and Fagus sylvatica seedlings along the whole distance interval up to 4 m. In a species-rich lowland alluvial forest, neigbourhood effects of trees and shrubs either increased or decreased the susceptibility of individuals to bark stripping and its intensity at distances of 2–30 from neighbouring individuals depending on the species of focal and neighbouring individuals. Finally, I illustrate that the local composition of tree communities can modify the susceptibility of woody individuals to herbivory and their survival at early life stages. I identify the species, life stage of focal and neighbouring individuals, type of natural enemies and light availability in the understorey as key factors determining the importance of neighbourhood effects. This dissertation also shows how and at what spatial scales enemy-mediated neighbourhood effects can contribute to community structure and composition.
|
|
|
System with Servos Controlled by Microcomputer
Veselý, Miroslav ; Kolář, Martin (referee) ; Zemčík, Pavel (advisor)
The goal of this bachelor thesis was to investigate possibilities of controlling RC servos by amicrocomputer. A part of this thesis was creation of a device for purpose of browsing distant surfaceby a laser. The created device is based on Arduino platform and it is possible to control this deviceremotely by a computer application.
|
|
|
Analýza využitelnosti jednoduchých indikátorů pastevního tlaku zvěře na les pro plánování lovu v honitbách
Rachůnek, Karel
This work deals with the analysis and evaluation of the usability of simple indicators of grazing pressure of game on the forest. The territory in the Zlín region was selected for the elaboration of this bachelor's thesis, specifically the hunting of MS Kyčera. The field survey was performed by the patrol method. Data from control and comparison areas (CCA), transects and artificial cultures were used to assess damage. Eight stands were selected for evaluation. Three main tree species in the area were evaluated, namely beech (Fagus sylvatica), Norway spruce (Picea abies) and white fir (Abies alba). Based on the damage by grazing pressure, the number of ungulates in the given area was evaluated.
|
|
|
Škody zvěří v honitbách Lesů České republiky,s.p., Lesní správa Šternberk
Ellnerová, Hana
This bachelor's thesis deals with game damage that was caused in hunting areas of the Šternberk forest administration. The aim was to verify whether the increased catch is reflected in the area of damage. Using a statistical investigation, I developed a regression analysis of the data, which showed that there is a relationship between hunting and damage. But this addiction has the opposite character than I expected. I thought that with increased hunting, the damage caused by game would decrease. In the case of my investigation, the amount of damage has an increasing tendency despite the increased catch.
|
|
|
Influence of vertebrates on recovery spruce and rowan growth in natural spruce forest of Krkonoše
SÍČOVÁ, Petra
Animal influence has in wood ecosystem big importace. Previously responded amount of animals to population curves of big beasts of prey. Since the time, when man started to regulate animals, he has to database, how big is each population and which density of animals is optimal according to local conditions. The aim of my work was to find out the influence of vertebrates on recovery and growth of Sorbus aucuparia and Picea abies. The research, I have been doing during growing season of the year 2007, contained field work on four LRA and one transect in Krkonoše. Work involved monitoring movement notes of vertebrates, schematic layouts of tree rings of experimental nurslings of spruce and measuring seeding of rowan. Counting, layouts and measurings were processed into schedules and consequently analysed. It was found, that amount of deer animals is raising and its influence on recovery is therefore more significant. Damage, which was found out on plants of spruce has raised since year 2000. Results has shown, that the slight browsing has increased by 10% compared to year 2000. Big effect on rowan recovery has instead of other also altitude which is connected with climatic conditios. By reason of raising deer animals in the area of Krkonoše national park and necessity its regulation, further monitoring of vertebrate influence on wood ecosystem is recomended.
|
|
|
Plant responses to deer browsing and the consequences for further browsing
Dudlová, Tamara ; Lepková, Barbora (advisor) ; Štenc, Jakub (referee)
(English) The bachelor thesis focuses on the interaction of plants and herbivores, specifically deer. The main question is if (and possibly how) the changes induced in the plants by deer browsing affect the probability of re-browsing. I tried to answer the question by reviewing published literature. Plants respond to browsing by tolerance (compensatory growth) or resistance (production of defensive chemical compounds), depending on the plant's life strategy. Tolerance prevails in adult woody plants and grasses; resistance prevails in young woody plants and forbs. In resistant plants, browsing increases the content of phenolic substances and decreases the cellulose content, while tolerant species react in the opposite way. It is the contents of these substances, which are negatively correlated, that are key to food selection by deer. Large species of deer generally prefer plants with more cellulose, which they are able to digest efficiently. Smaller species prefer plants with lower cellulose content and higher concentration of simple sugars. These more nutritious plants are protected from browsing by phenolic substances, which smaller deer species are able to neutralize more effectively. Only a few studies have addressed the issue of re-browsing of the same plants, and their results are ambiguous....
|
|
|
Effects of wild ungulates on vegetation in an abandoned landscape
Horčičková, Eva ; Herben, Tomáš (advisor) ; Diekmann, Martin (referee) ; Tichý, Lubomír (referee)
Wild ungulates are considered one of the major drivers for shaping terrestrial ecosystems, which has been developing since the early Cenozoic. Understanding the effects of ungfulates on vegetation is necessary for qualified knowledge how European landscape looked prior to human habitation and how it would look like without human intervention. Further, such understanding is of practical importance as management information necessary for managing abandoned landscapes. While the present-day wild ungulate European fauna does not contain several large grazers like auroch (Bos primigenius) anymore, the landscape has long been affected by them. It thus possesses historical experience of response to large grazers, which has been further maintained by livestock grazing. Importantly, the European landscape is experiencing a steady increase of populations of deer (Cervidae) and wild boar (Sus scrofa) with major effects of vegetation and landscape structure. While the effects of these present-day dominants have been studied mainly in forest habitats, there is a growing evidence that they both promote species diversity of forest understory and, interestingly, preferably feed in open vegetation and thus can affect broader landscape heterogeneity. The main aim of this thesis is therefore to examine effects of...
|
|
|
Tree sedlings and grazing.
Juřicová, Anna ; Weiser, Martin (advisor) ; Mayerová, Hana (referee)
My bachelor thesis resumes effects of forest grazing and browsing in the temperate climate region. Grazing can be useful tool in maintaining biodiverzity. However this effect strongly depends on abundance of herbivores and their selectivity. These results are based on studies that manipulated with grazing pressure, using exclusion or enclusion of the herbivores.
|
|
|
Effects of wild ungulates on vegetation in an abandoned landscape
Horčičková, Eva ; Herben, Tomáš (advisor) ; Diekmann, Martin (referee) ; Tichý, Lubomír (referee)
Wild ungulates are considered one of the major drivers for shaping terrestrial ecosystems, which has been developing since the early Cenozoic. Understanding the effects of ungfulates on vegetation is necessary for qualified knowledge how European landscape looked prior to human habitation and how it would look like without human intervention. Further, such understanding is of practical importance as management information necessary for managing abandoned landscapes. While the present-day wild ungulate European fauna does not contain several large grazers like auroch (Bos primigenius) anymore, the landscape has long been affected by them. It thus possesses historical experience of response to large grazers, which has been further maintained by livestock grazing. Importantly, the European landscape is experiencing a steady increase of populations of deer (Cervidae) and wild boar (Sus scrofa) with major effects of vegetation and landscape structure. While the effects of these present-day dominants have been studied mainly in forest habitats, there is a growing evidence that they both promote species diversity of forest understory and, interestingly, preferably feed in open vegetation and thus can affect broader landscape heterogeneity. The main aim of this thesis is therefore to examine effects of...
|
|
|
System with Servos Controlled by Microcomputer
Veselý, Miroslav ; Kolář, Martin (referee) ; Zemčík, Pavel (advisor)
The goal of this bachelor thesis was to investigate possibilities of controlling RC servos by amicrocomputer. A part of this thesis was creation of a device for purpose of browsing distant surfaceby a laser. The created device is based on Arduino platform and it is possible to control this deviceremotely by a computer application.
|
guest ::
