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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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Structure evolution of primary mixed temperate forests depending on disturbance regime
Dušátko, Martin ; Svoboda, Miroslav (advisor) ; Altman, Jan (referee)
Our thesis reconstructs disturbation history of primary forest remnant in Kornietová reservation in Slovakia. We extracted dendrochronological samples and collected data about the structure of a stand on sampling plots. 6 of total 14 plots were affected by an extreme disturbance around the year 1830. It removed almost complete upper canopy layer. This event was followed by a long period of minimal disturbance activity. The rest of plots was characterized by a regime of weak disturbances returning every 30 or 40 years. Between these two groups of plots, the shape of DBH distibution and the amount of large trees were significantly different. The plots which were affected by the extreme disturbance had distinctly more trees over 600 mm of DBH, because total extend of disturbances was markedly lower after 1830. The other parameters like amount of dead wood, species composition and quantity of saplings were not significantly different. The other studies suppose, that weak disturbances promote regeneration of beech, while large disturbances allow conifers to regenerate. The results of you study do not support such a relation. During data processing and evaluation, we discovered a high error rate the data suffered. It is more difficult to crossdate correctly a beech, then previously thought, but finally...
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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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