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An analysis of fungal exudate and carbon use efficiency
NÜBL, Laura
The exometabolome of various fungal functional guilds was investigated as part of the below-ground carbon flux. This thesis addresses the incorporation and exudation of carbon by individual, axenic fungal cultures, with a focus on developing a protocol for characterisation and identification of those compounds.
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Carbon sequestration by forest ecosystems in canging climate.
Hlaváčková, Lucie ; Lhotáková, Zuzana (advisor) ; Urban, Otmar (referee)
The global carbon cycle is in the focus of the scientists' interest, because understanding carbon sinks and their relationships can show the solutions of problems related with increasing CO2 concentration in the atmosphere in the future. I focused on the role of forests ecosystems in this carbon cycle. All forests cover almost one third of the Earth's land area. By photosynthesis they bind big part of atmospheric carbon to their biomass. Sink strength of forest can differ according to the type of biome, forest stand age and actual climatic conditions. Forest biomes can be generally divided according to the latitude to three groups: tropical forest biomes, temperate forests and boreal forests. The size of carbon stock decreases in this order. Other parameters, such as net primary production and respiration differ in dependence on the particular ecosystem. Tropical rain forests represent great carbon stock, but their deforestation causes massive C emissions back to the atmosphere. Boreal forests aren't considered as important carbon sink, but they influence local climate. Some speculations can also appear about the old forests. It is possible to find authors, who claims, that old forests are no more carbon sinks, so that their carbon balance is neutral. Many surveys prove that they bind less carbon...
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Effects of Climate change on root dynamics in temperate forests
Růžičková, Kateřina ; Bouda, Martin (advisor) ; Stiblíková, Pavlína (referee)
Fine roots contribute significantly to the global carbon and water cycle. Their dynamics and changes that may occur are therefore key players in these processes. Climate change significantly affects the dynamics of fine roots, and since individual factors are in interaction and may also function against each other, the overall response of the root system to climate change is difficult to predict. However, understanding these processes is essential for creating more accurate models to predict the response of ecosystems to a changing climate. This bachelor's project is a literature review that summarizes the knowledge about the effects of elevated temperature, CO2 concentration and drought on the dynamics of fine roots in temperate forests. Also, it provides a comprehensive view of the interaction of all three factors and considers some issues open for further research.
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Response of Soil Respiration, Temperature and Moisture to the Harvest of a Sessile Oak Forest\n
Dařenová, Eva
Forest management, particularly thinning and harvesting measures, has a significant impact on the forest carbon balance. In this study, we investigated the effect of the harvest of a sessile oak forest on soil respiration as a main source of CO2 emissions in forest ecosystems. Soil respiration, temperature and moisture were measured during the two growing seasons, one before and one after the harvest applied on six out of nine studied plots in April 2018. The harvest increased soil temperature by up to 6 °C. Soil moisture did not differ between the plots in 2017, but it was higher in the harvested plots compared to the control in 2018. In the first half of the growing season 2018, the difference between the control and harvested plots ranged between 5 and 100 % in proportion while in the second half the differences decreased only up to 5%. Soil respiration ranged between 1.2 and 3.3 µmol CO2 m-2s-1 during 2017 with no difference between the following variants. In 2018, soil respiration ranged between 1.2 and 7.0 µmol CO2 m-2s-1 and it tended to be higher in the harvested plots compared to the control. The exception was observed shortly after heavy rainfall on 5th September when soil respiration in the control significantly exceeded that in the harvested plots.
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Methods of CO2 separation from air, ways of its use and long-term storage
Kober, Ondřej ; Baláš, Marek (referee) ; Škorpík, Jiří (advisor)
Combustion of fossil fuels creates greenhouse gas emissions that cause global warming. The most important of these gases is carbon dioxide. Although it occurs naturally in the atmosphere, human emissions upset the balance of various natural processes. The aim of this bachelor’s thesis is to conduct a background research in the field of carbon dioxide capture, storage and utilization. The thesis also describes the role of carbon dioxide in the atmosphere, its cycle and human influence on carbon dioxide concentration.
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Methane emissions from temperate freshwater reservoirs
Bašta, Jan ; Frouzová, Jaroslava (advisor) ; Rulík, Martin (referee)
Methane (CH4) emissions from temperate freshwater reservoirs have only been evaluated for the last several decades. Freshwater ecosystems (including water reservoirs) release crucial quantities of this important greenhouse gas. Ebullition that releases methane into the atmosphere from bubbles originating from sediment is important source of methane. Regardless of the importance of these emissions, a very limited number of scientific research papers monitoring this flux into the atmosphere are available. Estimated values of methane emissions from freshwater temperate reservoirs vary considerably. There are many different methods for monitoring methane emissions. It seems that the freshwater reservoir stimulates methane formation in increasing scales. The size of the sum of methane emitted from freshwater reservoirs is also difficult to say.
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Carbon-smart forestry for building resilience to global change
Brnkalakova, S. ; Kluvánková, T. ; Marek, Michal V.
The specific role of mountain ecosystems in the carbon cycle and their importance as carbon sinks already\nhas been noted within the broader debate about climate change. There has been progress in designing\nand attempts towards implementing such mountain-specific strategies as green economies, global and regional\nconventions, frameworks, and institutions. There is still need, however, for new and integrative approaches\nto governing mountains in a sustainable and adaptive way with local and global contributions.\nThe proper institutional arrangement, adaptive forest management, and sustainable use of forest ecosystems\ncan make a substantial contribution to the well-being of local communities as well as contribute to\nmitigating global climate change by provisioning of carbon sequestration ecosystem service. This paper\nexamines how reconfiguration of social practice in forest-dependent communities can address urgent societal\nchallenges. In particular, it considers the potential of a common pool resource regime for governance\nand carbon-smart forestry in innovative management of mountain ecosystems to meet societal and natural\nchallenges.
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Carbon sequestration by forest ecosystems in canging climate.
Hlaváčková, Lucie ; Lhotáková, Zuzana (advisor) ; Urban, Otmar (referee)
The global carbon cycle is in the focus of the scientists' interest, because understanding carbon sinks and their relationships can show the solutions of problems related with increasing CO2 concentration in the atmosphere in the future. I focused on the role of forests ecosystems in this carbon cycle. All forests cover almost one third of the Earth's land area. By photosynthesis they bind big part of atmospheric carbon to their biomass. Sink strength of forest can differ according to the type of biome, forest stand age and actual climatic conditions. Forest biomes can be generally divided according to the latitude to three groups: tropical forest biomes, temperate forests and boreal forests. The size of carbon stock decreases in this order. Other parameters, such as net primary production and respiration differ in dependence on the particular ecosystem. Tropical rain forests represent great carbon stock, but their deforestation causes massive C emissions back to the atmosphere. Boreal forests aren't considered as important carbon sink, but they influence local climate. Some speculations can also appear about the old forests. It is possible to find authors, who claims, that old forests are no more carbon sinks, so that their carbon balance is neutral. Many surveys prove that they bind less carbon...
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Dynamics of aboveground biomass of a sedge fen
HAŠEK, Ladislav
This thesis is part of Project of the Grant Agency of the Czech Republic No P504/11/1151, focused on the role of plants in the balance of carbon dioxide and the other greenhouse gases produced in the ecosystem of a sedge fen, which is situated on the study site Wet Meadows near Třeboň. The thesis deals with the growth dynamics of the dominant sedge, Carex acuta. The samples were taken using the method of successive harvests near the automatic meteorological station of Czech Globe, Academy of Sciences of the Czech Republic. During the growing season nine harvests were accomplished on 25.3, 15.4, 6.5, 5.6., 9.7., 5.8., 9.9., 21.10., 25.11.. On each date eight replicates were taken, i.e., a total of 72 samples within the vegetation season. The seasonal dynamic of the above ground biomass was compared between C. acuta and the other plant species on the experimental area. Both live and dead biomass, was harvested and subsequently sorted to single botanic species, dried, weighed and the values were processed using the MS Excel tables. The seasonal maximum of aboveground biomass of all plant species (both live and dead parts) was found on 9.7. (1452,72 g.m-2). Among plant species the highest values of aboveground biomass were attained by Calamagrostis canescens (1257,93 g.m-2) and C. acuta (1163,49 g.m-2). C. acuta displayed the highest density of all shoots on 15.4 (300 m-2),and the highest average weight of one shoot. The maximum length of the longest live shoot of Carex acuta was very consistent among the measurememnts.
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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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