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Litter decomposition requires the presence of corresponding degradative enzymes, produced mainly by fungi. Forest soils show considerable spatial heterogeneity of distribution of these enzymes at diferent scales. Moreover, enzyme pruduction varies during the year, usually accompanied by the change in fungal community composition. In this work I examined if this spatial heterogeneity can be seen even at a scale of an individual leaf and whether the fungal community differs among enzyme activity hotspots and inactive parts of the leaves. Another goal was isolation of celulytic fungi from cellulose litterbags incubated on forest floor using particle filtration and dilution-to-extinction method. In a broadleaved forest dominated by oak leaves at different stages of decay were collected: senescent leaves on twigs, and leaves after 2, 10 and 22 months of decomposition. Ten leaves per season were taken for analysis of cellobiohydrolase activity over the leaf surface. Leaves were attachmed onto melted agarose plate and leaf surface was covered with low melting point agarose containing fluorescently labelled substrate. For each leaf a map of enzyme activity was created and area with the high and low enzyme activity was identified. From both sites a square of approx. 1 cm2 was cut out, DNA was extracted and fungal...

This thesis is a part of the project No. P504/11/1151 of The Grant Agency of the Czech Republic, entitled The role of plants in the greenhouse gas budget of a sedge fen. In this thesis, the decomposition rate of a standard material (cellulose) is assessed for three types of wetlands, which differ in water regime. The study took place at two localitites of marginal wetlands with standing water (Mokré louky near Třeboň, Záblatské louky), two floodplain localities (Brouskův mlýn and Hamerské louky) and two peatbog localities (intact and mined parts of Červené blato, respectively). The intensity of decomposition processes was compared among the sites using the method of cellulose bags. The bags were made from nylon nets, each was divided into five pockets and a cellulose strip was inserted in each pocket. A filter paper was used as the cellulose. These bags were placed vertically into the soil profile so that the upper sample was lying on the surface and the lowest was at the depth of 25 cm below the surface. At each locality four places were randomly selected and four replicate bags with cellulose were placed on each of them. In total 96 bags were put in place, which makes 480 cellulose samples. Two experiments, differing in length of exposition, were carried out in 2013. The samples were taken from the field sites after three and five weeks of exposure (experiment No. 1 and 2, respectively). In both experiments, the decrease in ash-free dry matter was the highest at Hamerské louky. The lowest decrease in ash-free dry matter was in the mined part of Červené blato peatbog. In the second experiment the decrease of the ashless dry matter was more noticable, which was caused by the prolonged exposure. The lowest decrease of ash-free dry matter was found in depths of 0 - 10 cm below the soil surface at all the sites.

Leaf litter in temperate forests represents an important input of carbon into the soil. Main players in the decomposition of leaf litter are fungi and bacteria. While the role of fungi in litter decomposition was repeatedly addressed, there are just a few field studies where litter-associated bacteria were also considered. The aim of this work was to summarize available literature studying the structure and function of bacterial community during litter degradation. The nature of different possible substrates is discussed. Genetic approach is briefly outlined. Factors such as diversity, spatially distribution and abiotic factors that can influence community are also considered. It can be supposed that community composition changes with the change of litter chemistry and nutrient availability. The development of bacterial community might be driven by the decreasing availability of nutrients in litter. Labile compounds are utilised at the beginning of decomposition, while recalcitrant substrates are utilised later by specialist taxa. Members of the phyla Actinobacteria, Acidobacteria, Bacteroidetes and Proteobacteria seem to be dominant during decomposition. Different types of relationships between fungi and bacteria also most likely influence the composition of community. This review shows that the bacterial...

This work deals with the decomposition of cellulose in wetland. The speed decomposition has been studied in several areas. Mokré Louky u Třeboně, Záblatské louky, Červené blato mined and not mined. The intensity of degradation processes were determined using the litter-bags. The experiment was done for two years and each year was used another method. Bags with cellulose were placed in the soil and the soil surface. In this work the values were determined in different places and at different times.