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Habitatové preference, stanovištní dynamika a management hmyzu vázaného na staré stromy
PLÁTEK, Michal
The thesis presents studies on habitat preferences of beetles associated with senescent, open-grown trees and on dynamics and management of saproxylic habitats. It presents a brief insight into the current issues in the conservation of insects dependent on old trees. It presents the patterns of exploitation by a veteran tree specialist within old open-grown trees and the local patterns of tree exploitation by the same species at sites with different characteristics. Further, it presents a study of the effect of a prunning technique on formation of deadwood microhabitats, and also the importance of active interventions in closed-canopy forests for the communities in temperate lowland woodlands.
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Bacteria associated with decomposing deadwood
Tláskal, Vojtěch ; Baldrian, Petr (advisor) ; Uhlík, Ondřej (referee) ; Bárta, Jiří (referee)
Deadwood is a hotspot of microbial diversity and its decomposition contributes to carbon and nitrogen cycling in temperate forests. The historically recognized importance of fungi in the decomposition of deadwood has recently been complemented by the description of bacterial functions thanks to the rapid progress of culture-independent methods based on the analysis of nucleic acids. To study different aspects of deadwood decomposition, a temperate mixed forest in Zofinsky prales National Nature Reserve was selected as a site with rich historical forestry data where deadwood decomposition represents an important process in wood turnover. The aim of this thesis is to describe role of bacteria in deadwood decomposition at fine scale resolution with respect to community composition, enzyme transcription, and metabolic potential of dominant species. Effects of deadwood age together with pH and water content on the bacterial community composition proved to be more important than tree species identity. Bacteria showed distinct composition between early and late community in decomposing deadwood. The bacterial community was also under a significant influence of fungal community composition. Despite being in a close contact, bacterial and fungal communities differed significantly between deadwood and the...
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The importance of bacteria for deadwood decomposition in forest ecosystems
Némethová, Ema ; Baldrian, Petr (advisor) ; Bárta, Jiří (referee)
Forest ecosystems represent a huge reservoir of carbon. The volume of deadwood in managed forests is in the tens of m3 h-1, while unmanaged forests have the volume of deadwood in hundreds of m3 ha- 1. Deadwood is a substrate with a high potential for decomposition. However, deadwood is a specific habitat that has a high C/N ratio and changes due to ongoing decomposition. The C/N ratio decreases with increasing decay time. In addition to the C/N ratio, the pH also changes during the wood pulping process, due to the decomposition of plant biomass by fungi. Moreover, deadwood has a high impermeability. The main decomposers of dead wood are fungi. In addition to them, bacteria, which are numerous in deadwood, also contribute to decomposition. Bacterial communities that decompose woody biomass are affected by these factors, and their distribution is also affected by dead tree species. The aim of this study was to describe how bacterial communities associated with deadwood change during decay. The most significant factor in the decomposition by bacterial communities is the time of decay. Bacteria found in short-decaying wood (less than 16 years old) are more diverse than those found in long-decaying wood. Methylotrophic bacteria and N-fixing bacteria are common in short-decaying wood as well. N-fixing...
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Assembly, successional development and functioning of microbial communities in deadwood
Bernardová, Natálie ; Brabcová, Vendula (advisor) ; Kopecký, Jan (referee)
Dead wood is one of the most important reservoirs associated with forest ecosystems. In natural forests, its volume is counted in hundreds of m3 ha-1 , whereas it reaches only tens of m3 ha-1 in productive commercial forests. In contrast to soil and plant litter, deadwood is unevenly distributed on the forest floor. The specific physicochemical properties such as high content of recalcitrant polymers, low nitrogen level and impermeability negatively affect the rate of decomposition especially in the initial stages of wood deconstruction. The deadwood decomposition is very slow in comparisons with other substrates, it accumulates and thus it represents the important reservoir of nutrients. This thesis is focused on the structure, development and function of microbial (fungal) community in decomposing deadwood in unmanaged forest. Functional screening of fungi isolated from fruit bodies collected from coarse deadwood was set aside. Physico-chemical properties of deadwood including pH, carbon and nitrogen content and microbial biomass were estimated for four wood decomposition stages and three different tree species. New generation sequencing (Illumina MiSeq platform) was applied for fungal community structure analysis based on ITS2 fragment. Fungal functional screening was based on physico-chemical...
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Structure and function of bacterial communities during succession on dead plant biomass
Tláskal, Vojtěch ; Baldrian, Petr (advisor) ; Marečková, Markéta (referee)
The decomposition of dead plant biomass substantially contributes to the carbon cycle and therefore is one of the key processes in temperate forests. While the role of fungi in litter and deadwood decomposition was repeatedly addressed, there are just a few surveys of bacteria associated with decomposing plant biomass. The development of bacterial community within leaf litter is likely driven by the changes in litter chemistry and by the availability of nutrients in the litter. Fungal activity greatly contributes to changing properties of substrate and thus influences bacterial community. Availability of nutrients is changing during biomass decomposition from easily accessible substrates toward more recalcitrant ones (e.g. lignin). The colonization of deadwood by bacteria is influenced by various factors such as microclimate conditions, tree species and volume. The aim of this thesis was to describe bacterial community dynamics during the first two years of decomposition of leaf litter and deadwood. In the leaf litter experiment, bacterial community was analysed in the live, senescent and decomposing leaves of Quercus petraea. This experiment was performed in the Xaverovsky Haj Natural Reserve, Czech Republic. Deadwood experiment was focused on the composition of bacterial community in the initial...
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Enzyme activity and molecular characterization of fungi in decaying wood
KONAROVSKÁ, Kristýna
Decomposing wood is necessary part of forest ecosystem. Wood is robust and hardly decomposable material. Some fungi can use enzymes to degrade lingocellulose. This bachelor thesis is concerned with these fungi and enzymes. Goal of this work was to describe factors affecting composition of fungal community in deadwood. Two different kinds of trees - beech and fir had been sampled from trunks and branches and ergosterol content, fungal biomass, activity of extracellular enzymes and fungal community composition were determined. Main watched property has been different source of samples coming from tree trunks (T) or branches (B) and from Silver fir (FWD) or European beech (CWD) thus forming 4 categories FWD-T, FWD-B, CWD-T and CWD-B. Analysis confirmed higher potential activity of enzymes and higher pH in samples taken from branches specifically endocellulose, exocellulose, endoxylanase, N-acetylglukosaminidase a -glukosidase. Ergosterol marker confirmed higher biomass content in branches. Ascomycet or Basidiomycet fungi content was not dependent on type of wood or its size. Enzyme activity and fungi biomass with lower pH confirms higher fungi enzymes content in branches in comparison to trunks. Presence of fungi influences substrate thanks to active metabolism. Higher biomass values were linked to faster branches colonization and their decomposition.
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