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Importance of fungal decomposition of wood in the ecosystems of natural forests
Štercová, Lucie ; Baldrian, Petr (advisor) ; Kolařík, Miroslav (referee)
The decomposition of organic substrates represents an important part of the global carbon cycle and affects its global change through CO2 release. In temperate forests, deadwood represents a large carbon stock, its amount and decomposition is crucial for ecosystem biodiversity and functioning. The fungi are omnipresent powerful decayers in all terrestrial ecosystems. Their ability to decompose all deadwood compounds, mainly lignocellulose, is highly important. Without fungi, the wood decompositions and the release of withheld nutrients back to nutrient cycles couldn't be performed. While many studies were concerned with the estimation of decomposition rates of deadwood, still deeper knowledge about microbial decomposition processes and the diversity of saproxylic species and their interaction is needed. The fungi are still underrepresented in dead wood studies. This study had two main objectives. First was to describe the fungal community on downed deadwood of Fagus sylvatica and Abies alba in natural forest of Salajka in the Czech Republic, to reflect the substrate changes during the different decay stages, and to link the enzyme activities to fungal community composition and their described ecophysiologies. Second aim was to describe the fungal communities on standing and downed dead logs of...
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Ecology of deadwood-associated fungi in the ecosystems of nature-like forests
Zrůstová, Petra ; Baldrian, Petr (advisor) ; Konopásek, Ivo (referee)
Dead wood plays an important role in forest ecosystems in the context of C dynamics, nutrient cycling, forest regeneration and biodiversity. Decaying wood sustains biodiversity by providing habitats and energy for fungi, bacteria, invertebrates, and many other organisms. Dead wood is resistant to decomposition and its decay is driven mainly by filamentous fungi. Community structure of wood- inhabiting fungi changes during decomposition, but the relationship between substrate quality and decomposer community is still poorly understood. This work studied fungal community composition with respect to tree species, stage of decay, volume and physico-chemical properties (such as pH, carbon and nitrogen content) of dead wood. Fungi were identified using next generation sequencing approaches - 454-pyrosequencing and Illumina MiSeq sequencing. Tree species, volume of dead wood (branches x logs) and stage of decay were the main variables affecting fungal community composition. Higher enzyme activities and content of fungal biomass indicate faster colonization of small branches than tree trunks by fungi. Fungal community composition, wood chemical properties and enzyme activities changed during decomposition. Both content of nitrogen and fungal biomass increased during decomposition. Enzyme activites peaked...
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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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