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Peat formation and peat meadow restoration
Krejčová, Jana ; Frouz, Jan (advisor) ; Picek, Tomáš (referee)
This work aims to clarify and describe the necessary conditions of the peat soil horizon formation. The following three types of locations were compared. Drained locations that were revitalized afterwards. Locations which were drained and never revitalized. And lastly undrained localities where the original peat horizons are still presented. It has been proven that the grounwater level differs in drained and undrained areas. However, there was no significant differrence between revitalized and non-revitalized areas in drained types of locations. The results confirmed that Sphagnum spp., which is the most important species in peat formation, dominates the plant community where the groundwater level is higher than 25 cm. If the grounwater level is lower than 25 cm below the surface, Sphagnum spp. disappears very quickly and degrades peat soil horizons. The work also proved the groundwater level directly affects plant comunities that more or less promote carbon accumulation in the soil but water level and anaerobic conditions have no direct affect on soil carbon accumulation and only affect the vegetation composition of the peat soil horizon.
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Cyanobacteria and microalgae associated with mosses in wet meadows (High Arctic)
POLÁŠKOVÁ, Anna
Associations of nitrogen fixing cyanobacteria with mosses in wet meadow habitats of central Svalbard are of significant ecological importance as they represent a dominant nitrogen source. The first aim of this thesis was to find a suitable method to mechanically dislodge cyanobacteria from the moss stems, which would allow subsequent cyanobacterial identification and quantification. The second aim was to perform pilot Sanger sequencing which would allow to obtain another assessment of the cyanobacterial community for future studies of the wet meadow.
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The Methane flux (CH4) from willow (Salilx sp.)
JANEBOVÁ, Klára
The aim of the thesis was to study the methane flux (CH4) from crack willow (Salix fragilis) and bay willow (Salix pentandra) at the ecosystem station Wet Meadow by Třeboň (49°01 N; 14°46 E). The research was carried out in May 2016. Methane is one of the important greenhouse gases, which plants can emit into the atmosphere. Neither the fluxes of methane from willows nor the factors influencing them were so far sufficiently monitored. The thesis became a part of the whole year's monitoring of these fluxes, carried out by the Global Change Research Institute of the Czech Academy of Sciences, under the lead of expert consultant Dr. rer. nat. Mgr. Macháčová. The fluxes of CH4 were measured with the help of manual static chamber systems located in three height-levels and online portable laser gas analyser. The fluxes were processed, statistically evaluated and coherent tables and charts were created from the results. Based on these results we can conclude, that all examined trees have released CH4 and CO2 from their trunks, however no significant statistical difference between morning and afternoon fluxes was measured. S. fragilis was emitting higher amounts of CH4 and CO2 than S. pentandra. At the same time emissions dramatically decreased along with decreasing trunk height. Therefore the highest emissions were detected directly at the ground level. Moreover, the emissions of CH4 and CO2 were measured from the soil as well.
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The effect of drainage and restoration on vegetation of wet peaty meadows.
Krejčová, Jana ; Frouz, Jan (advisor) ; Syrovátka, Oldřich (referee)
The aim of this thesis is to summarise the current knowledge of the effects of amelioration entervention especially drainage on wet meadow vegetation. First part of this thesis consisting of literature review of scientific papers and other studies summarises the influence of water on soil. It describes how the loss of water and degradation of soil influence the plant communities of wetlands. Drainage of wetlands was very common due to the intensification of agriculture in the past. The amelioration intervension resulted in the loss of peat horizon in soil and reduction of biodiversity. This review explains the reasons to common drainage in the past. In conclusion of the review, the thesis evaluates the efficiency and possibilities of wetland biotopes restoration. The second part of the thesis describes the specific research in the village Senotín (running between 2015 and 2016) which compared the results of the studies from 1996 and 2016. The effectiveness of restoration was examined and compared on the basis of phytosociological images of vegetation which are presented on three different types of areas.
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Factors determining the vegetation composition of wet meadows and its changes in time
Šimák, Martin ; Münzbergová, Zuzana (advisor) ; Procházka, Tomáš (referee)
This thesis is mainly a literature review of scientific papers and other studies of wet meadows and their characteristics. The aim of the thesis is to summarise knowledge especially of the changes of the vegetation composition of the wet meadows, reveal the causes of such changes and consider the influence of different types of management. Wet meadows underwent crucial changes. They have been drained, the grazing or mowing has ended up and many species were unable to adapt to the changed conditions. Biodiversity in general has been decreasing on these habitats and it has been caused mainly by the total change in management. By comparing different scientific papers I identified common characteristics of the declining species and optimal managment options suitable for stopping their decline were detected. Consequently, I introduce the main methods used to study changes in vegetation composition over time. In the final part of the thesis I mention Slavkovský Les as the area where my future research will be conducted.
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Changes of the vegetation of wet meadows depending on management
HORNÍK, Jan
Central Europe wet meadows are characterized by considerable species richness. The biodiversity maintenance of the wet meadows is connected with regular management (i.e. grazing or mowing). As their area drastically decreased due to changes in land use in the last century, they have become the object of interest among scientists, conservation biologists. This thesis is composed of three original studies which are focused on escribing diversity patterns of the whole spectra of wet meadows at landscape level and dynamic of their changes depending on different management regimes (mowing/abandonment,fertilizing/unfertilizing). The synthesis of these studies reveals the description of the processes underlying the wet meadows species loss depending on land use changes and proposes the principles for sustainable conservation management.
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Decomposition of aboveground biomass of a herbaceous wetland stand
KLIMOVIČOVÁ, Lucie
The master?s thesis is part of the project GA ČR č. P504/11/1151- Role of plants in the greenhouse gas budget of a sedge fen. This thesis deals with the decomposition of aboveground vegetation in a herbaceous wetland. The decomposition rate was established on the flooded part of the Wet Meadows near Třeboň. The rate of the decomposition processes was evaluated using the litter-bag method. Mesh bags filled with dry plant matter were located in the vicinity of the automatic meteorological station at four randomly selected sites. Values of the decomposition rate were assessed in two experiments. In the first experiment the litter bags were fixed in April 2009. The litter bags were fixed in the vertical position and they had one size. Values of the decomposition rate were assessed for 6 sampling dates and the total exposure time was 2,5 years. The decrease of the total dry mass was 18,37 % in the first year and 13,05 % in the second year. The value of LDR was 0,7227 in the first year and 0,4740 in the second year. In the 2nd experiment the litter bags were fixed in November 2010. The litter bags were fixed in the vertical and horizontal position, respectively, and they were of two sizes (small, big). Values of the decomposition rate were assessed for 2 sampling dates and the total exposure time was one year. The total annual value of LDR was 0,5212 for the vertical bags and 1,0676 for horizontal bags.
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Effect of fertilization on leaf anatomy of Carex acuta
HŮRKOVÁ, Drahomíra
This thesis is part of the project GA CR No 526/09/1546 ("Importance of newly assimilated carbon to the interaction of plants with soil in grassland and wetland ecosystems in varying environmental conditions"). The was focused on differences in leaf anatomy of plants subjected to different nutrient regimes. Stands dominated by C.acuta were studied in two localities - wetlands: Záblatské meadows with organic soil and Hamr meadows with mineral soil. Effect of fertilization was studied in areas subjected to doses of fertilizer of 300 kg NPK. ha-2 (HIGH treatment) and unfertilized areas (NO treatment). These doses were applied from 2006 to 2008, but not in 2009 because of continuous flooding. All leaves of C. acuta were hypostomatic. At Hamr, the average stomatal densities were 724 {$\pm$} 88 mm-2 and 820 {$\pm$} 130 mm-2 on the lower side of leaves of unfertilizer and fertilized plants respectively. At Záblatské louky, the average stomatal densities were 872{$\pm$}114 mm-2 and 849{$\pm$}125 mm-2 on the lower side of the leaves of unfertilizer and fertilized plants, respectively.
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Effect of mineral nutrient availability and flooding on the growth of Carex acuta in a mesocosm experiment
SYCHROVÁ, Jana
This MSc thesis is part of the project GACR 526/09/1545 Importance of newly assimilated carbon for the plant-soil interactions in wet grassland ecosystems in varying environmental conditions, which focuses on the effects of eutrophication on selected wet meadows with mineral or organic soil in the Trebon Biosphere Reserve. The results of this project will serve as a basis for developing a suitable ecosystem management for wet meadows, especially for sites registered as nature reserves. Pot experiments were carried out with Carex acuta, a dominant species of wet meadows that has already been subject of many studies. The aim of this work was to find out how C. acuta responds to different levels of fertilization and soil flooding under controlled conditions. The growth of the generative shoots of C. acuta was significantly affected by fertilization. The growth of vegetative shoots was significantly influenced by the soil organic matter content and fertilizer addition. The vegetative shoots reached greater length than the generative shoots. The pot experiment indicates that fertilization has not a large influence on the growth of C. acuta. This finding may explain field observations that C. acuta is gradually replaced in eutrophic habitats by stronger competitors, especially Phalaris arundinacea.
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