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Effects of forest management on forest biodiversity
Dušátko, Martin ; Svoboda, Miroslav (advisor) ; Bače, Radek (referee)
Forests host approximately 80 % of species of all terrestrial organisms. Human pressure on forest ecosystems drastically increased during 20th century and poses a constant threat to global biodiversity. The aim of this thesis is to summarize current knowledge of the effects of forest management on organisms and to identify underlying mechanisms. The oldest forms of forest management techniques were coppicing and coppicing with standards which enable relatively high biodiversity of species of early successional stages. Transition to classical intensive forestry caused shielding vegetation from the sun and decrease of heterogeneity. In recent decades some further intensification of management is practiced by using fast growing trees, but awareness of the need to establish sustainable forestry conditions strenghtens. Managed forest contrary to natural one has substantially lower average age of trees, it shows spatial homogeneity and old and dead trees, elements that are tied to high diversity of organisms, do not occur. Species composition of woods changes often. Anthropogenic management also disrupts and weakens the natural disturbation regimes. In many economically developed countries forests have been fragmented for a long time and in vastly forested areas that have persisted to the 20th century massive...
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Effects of forest management on forest biodiversity
Dušátko, Martin ; Svoboda, Miroslav (advisor) ; Bače, Radek (referee)
Forests host approximately 80 % of species of all terrestrial organisms. Human pressure on forest ecosystems drastically increased during 20th century and poses a constant threat to global biodiversity. The aim of this thesis is to summarize current knowledge of the effects of forest management on organisms and to identify underlying mechanisms. The oldest forms of forest management techniques were coppicing and coppicing with standards which enable relatively high biodiversity of species of early successional stages. Transition to classical intensive forestry caused shielding vegetation from the sun and decrease of heterogeneity. In recent decades some further intensification of management is practiced by using fast growing trees, but awareness of the need to establish sustainable forestry conditions strenghtens. Managed forest contrary to natural one has substantially lower average age of trees, it shows spatial homogeneity and old and dead trees, elements that are tied to high diversity of organisms, do not occur. Species composition of woods changes often. Anthropogenic management also disrupts and weakens the natural disturbation regimes. In many economically developed countries forests have been fragmented for a long time and in vastly forested areas that have persisted to the 20th century massive...
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The sprouting dynamics of coppices on experimental clear-cuts of Podyjí National park
Pech, Jiří ; Bače, Radek (advisor) ; Čada, Vojtěch (referee)
This bachelor thesis is dealing with literature review of the subject coppice and coppice-with-standards forest in Czech Republic as well as in Europe. It is concerned with definition of these coppice systems, historical and current progress of coppice and its distribution in Czech Republic and European Union. Further questions of the thesis are, if there is any reason to continue or to renovate silviculture of coppice and if so, for what reasons and what is optimal rotation period in coppice. Description of principal tree species with sprouting ability in Central Europe are included in the thesis as well.
In the second part of the bachelor thesis sprouting ability in experimental research plots in National Park Podyjí are evaluated. The sprouting ability is evaluated for three principal tree species in Central Europe, oak, linden and hornbeam. The thesis compares interspecies relations in the initial growing speed of the shoots and the ability to produce the shoots in relation to diameter of the stump. Further the thesis is dealing with growing speed in relation to the amount of available light.
Measuring, after five growing seasons, in total of twelve experimental plots, discovered the highest sprouting ability by linden (87%), then oak (43%) and hornbeam (32%).
The thesis pointed out the significant interspecies differences in the ability to produce shoots. But the reliance of shoots producing on stump diameter has not been proved (for oak and hornbeam).
Because the relationship between the height increment of shoots and the amount of available light was not significantly demonstrate, it can be assumed, that experimental plots (forest clearing) are extensive enough and the sprouting ability is not limited by the amount of available light.
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Growth and mortality of natural regeneration after dieback of tree layer of mountain spruce forest
Červený, Jan ; Bače, Radek (advisor) ; Synek, Michal (referee)
The aim of this study is to assess the state of the natural generalization after the death of the upper tree layer in the mountain spruce forest, based on data acquired on permanent research area (50x50 m) where the collection of the data is in progress since 2006 in the area Trojmezná. These areas were damaged by hurricane Kyrill and afterwards bark beetle calamity in 2008. In these areas were defined squares of size 5x5m and they were divided into cells 0,5x0,5m and these shelf is recorded every individual, the increment, health and microhabitat. By the analysis which was carried out, was found, that woody representation is not different from the representation of upper tree layer, the number of spruce is 97% and 3% of the crane. Most individuals were caught before the disturbances, the youngest individuals germinated in 2006. Higher individuals achieve higher gains than smaller individuals, it means that the heterogeneity of the height structure is increasing. Based on analysis of mortality individual squares (50x50m) was found that after the disturbance on TVP new places without trees were not formed. The dependence of mortality on frequency of individuals in the cells (0,5x 0,5m) has not been demonstrated. That means that mortality of individuals at intraspecific competition is yet significantly independent, although abundance exceeded 17 individuals per cell. Eight years after disturbance is mortality very low. The highest regeneration grows up to 20 cm per year.
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Principles of ecological forestry and possible applications in Czech republic
Brichta, Jakub ; Čada, Vojtěch (advisor) ; Bače, Radek (referee)
This bachelor thesis deals with the principles of ecological forestry, and also with its possible use in the Czech Republic. To a large extent, the thesis also focuses on natural disturbances, which use is the cornerstone of ecological forestry. I foccus specially on small-scale disturbances that help to create heterogeneous ecosystem through dead wood acumulation and sun exposition. Natural disturbances are part of the principles of ecological forestry and without their presence to a greater, extent: we can not talk about forest management being ecological. Disturbance affect the amount of biological legacies, the course of natural succession, but also the actual diverse mosaic of plant and animal communities. As there are diverse opinions on natural disturbances and application of natural processes in forests, there are many issues that need further examination. Therefore, the research of the forest natural disturbance regimes falls among the crucial present scientific challenges.
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Overstory-understory neighborhood effect in mountain mixed forest
Matouš, Marek ; Bače, Radek (advisor) ; Ulbrichová, Iva (referee)
The object of this study is to describe overstory-understory neighbourhood effects in natural mountain mixed forests in environmental conditions of central Europe. Namely, the neighbourhood effect of European beech (Fagus sylvatica L.), silver fir (Abies alba Mill.) and Norway spruce (Picea abies [L.] Karst. ).
The sample plots are situated in central Slovakia. On 60 plots, counts of individuals of these species were recorded and divided by social status (from 6 cm of DBH). Regeneration of these species, was divided into 4 high categories. For 30 trees of each species, regeneration was also counted under specific crown in the area of 4 m2. The data was evaluated mainly by the generalized linear model in R statistical program. Here was evaluated the relationship between individuals of different categories of understory and overstory and the dependence between counts of regeneration of each species under specific crown.
The strongest positive overstory-understory neighbourhood effect, was observed for the silver fir in all categories of regeneration (p<0.001). It also weakly negatively affected the regeneration of beech. For spruce, the positive neighbourhood effect was demonstrated only among the trees of upper level and saplings from 0.5 to 1.3 meters. Other categories of spruce saplings, were in too small quantities for demonstrating these relationships. Positive overstory-understory neighbourhood effect of beech was weak, or neutral for advanced regeneration. But seedlings to 0,5 m height, were in minimum quantity under spruce and fir crown. Beech also significantly negatively influenced all regeneration categories of silver fir (p<0.001). So, for each species, the overstory-understory neighbourhood effect is more or less positive, at least for lower height regeneration categories. This effect suggest also to small scale species stability of these forests.
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History and presence of oak stands in Europe
Kloučková, Dominika ; Bače, Radek (advisor) ; Janda, Pavel (referee)
The aim of this work is to evaluate historical human impact on the expansion of European oak stands in the past through scientific publications and to find existing limitations that affect the oak recovery ability. The European historical forest is characterized by coppicing, of which origins date back to the Neolithic period. The coppice featured vegetative renewal, in the coppice with standards there were left standards of the generative origin, often oaks. Both forms have a very long tradition in European countries. People used the sprouting capacity and the quick regeneration of oak especially for construction purposes and their need for firewood. Acorns secured the source of food for pig farming. Based on for example the ring width or pollen analysis, current methods of research permit to assess the impact of active management on the oak stands and outline the structure of primeval forests. It turned out that coppicing has a positive effect on the increment of oak standards and that the open landscape with a rich diversity of species, which features a picture of a primeval forest, was always maintained especially by a man starting forest fires. Since the mid-20th century, it was gradually transferred to the high shape of the wood, which favors generative way to recovery, and thus monocultures of often coniferous trees are created. Oak is currently health endangered tree species and its recovery is negatively affected by grazing deer (browsing), the influence of abrupt climate change, weed, pathogenic fungi of the genus Phytophthora, oak powdery mildew (Microsphaera alphitoides), tracheomycotic diseases or larvae of winter moth (Operophtera Brumata) and green oak moth (Tortrix viridana). Finally, it is inappropriately selected management that is not based on the rich history of this species and doesn´t preserve its characteristic natural properties.
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Disturbance history of the primary mountain mixed forests in Temperate Zone (Europe)
Komín, Stanislav ; Janda, Pavel (advisor) ; Bače, Radek (referee)
This paper is about structure and disturbance regime of mountain mixed forests in location Šrámkova dolina, which is in Tatras national park. Except this, thesis also informs about problems which are in mountain mixed forests. Forest dynamic were monitored od 14 permanent plots, which were in the line polygon, every plot takes 1000 m2. Study is based on the structural data of the type, thicknes and age structure and this data were put into dendroecological analys, which shows releases during the growth. Based on results, we can say that most trees strarts their growth in forests gap, and most of trees did not detect release. Šrámkova dolina were formed by gew several wind disturbances, biggest impact had few disturbances between year 1834 and 1845, this event strongly affected regenerations between decades 1845 and 1885. In the Europe temperate zone are mountain forests mostly affected by wind adn bark beatle, but in mixed forests are damage caused by bark beatle smaller. Small canopy destruction caused by small disturbance salso play very important role in forests dynmic here.
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Ecology and management of dead wood in the aquatic ecosystems
Málek, Jakub ; Bače, Radek (advisor) ; Kjučukov, Petr (referee)
This paper discusses the influence of deadwood on aquatic organisms and animals found in the vicinity of waters. The thesis also analyzes the economic aspects of the occurrence of deadwood in relation to water management. The chosen issue was addressed on the basis of findings of studies already carried. The work globally compares the abundance and species diversity of macroinvertebrates and fish in the environment of deadwood and the environment without wood. Effect of deadwood on the occurrence of selected species found in the area of Czech Republic was determined from available resources. Depending on the theoretical knowledge and ascertained facts, the economic pros and cons of deadwood are compared here. This work verified that the dead wood actually positively affects the density and species richness of communities of aquatic organisms. Regarding the deadwood and the occurrence of selected animals, due to the absence of necessary data, no connection has been confirmed. In the case of the importance of deadwood in water management, only ambiguous results were found. The author acknowledged this hypothesis to be valid, however, based mainly on theoretical knowledge. Overall, the results of the work indicate that deadwood could also have some economic benefits in connection with its ecological values, and therefore it is important to devote more of the scientific work to this issue, and based on them, it would be possible to evaluate these benefits.
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