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Changes in organic matter input to soil during pedogenesis as a driver of soil organic matter sequestration
Lačná, Karolína ; Frouz, Jan (advisor) ; Vindušková, Olga (referee)
Soil organic matter is an integral part of the soil representing a reservoir of nutrients for plant and soil organisms, especially in accumulation of a biogenic element carbon (C). The accumulation and stabilisation of soil organic matter depends on several mechanisms. The input source for the creation of SOM is the plant organic matter consisting mainly of the litter and above-ground part of the plant herbal biomass. The accumulation of SOM and carbon sequestration is primarily influenced by the chemical composition and amount of OM entering the soil. In this work, the entry of OM into the soil was experimentally verified at locations with an older naturally formed soil type and man-made soil (post-mining sites). As part of the research, other types of forest cover represented by spruce and alder stand were compared. From the measured data of the individual influencing factors, it was found that the composition and quantity of OM is determinated significantly with the species composition of the forest. More plant OM was observed in the alder trees area stands on both soil types with a lower C:N ratio, whic describes better decomposable OM. By contrast, there were no statistically significant differences between areas on young and old soils. The results suggest increased concentrations of...
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Biotic interaction and their role in organic matter turnover in soil
Radochová, Petra ; Frouz, Jan (advisor) ; Smrž, Jaroslav (referee)
The thesis brings overview of main taxa of soil organisms. It describes in detail their trophic and non trophic interactions that contribute to organic matter decomposition in soil. In particular soil food web and behavior of fungal and bacterial channel of food web is described in relation to organic matter decomposition, soil formation and humus formation. This work contains also experimental work sealing with interaction of soil microscopic fungi and invertebrates. Food preference and suitability for development of three fungal species growing on three different litter types was studied. Litter was more important for food preference and food suitability. There were disproportion between litter suitability and litter preference. In particular oak was not preferred by adults but very suitable for development.
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The importance of mycorrhizal fungi in the root decomposition.
Haiclová, Klára ; Kohout, Petr (advisor) ; Kolaříková, Zuzana (referee)
Mycorrhizal fungi are known as symbionts of many plant species. Fungi provide better access to mineral nutrients and water for host plants, and in return fungi receive carbohydrates from plants. Although a significant proportion of organic matter is bound in the root biomass, little is known about the factors affecting root decomposition. Understanding the process of root decomposition and the factors that affect it, is important to us. Knowledge of root decomposition helps us understand the carbon cycle and answer questions about carbon sequestration in soil. This Bachelor's thesis is focused on the importance and function of mycorrhizal fungi during root decomposition. It describes the influence of mycorrhizal fungi on the decomposition of fine roots colonized by mycorrhizae, the ability of mycorrhizal fungi to decompose organic matter and influence the decomposition rate through competition with saprotrophic organisms. Keywords: mycorrhizal fungi, roots, decomposition, rate, organic matter, soil, importance, carbon sequestration
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Study of decomposition of organic matter in soil using the method of "tea bags"
Lišková, Kateřina ; Sedláček, Petr (referee) ; Enev, Vojtěch (advisor)
The main aim of this master thesis was to introduce an optimal method which could be used for study of a decompostion of an organic matter in a soil. For this purpose was chosen based on a literaly review so-called tea bag method. With regard to the completeness of the work, a physico-chemical characterization of the soil environment and HS isolated from it was also performed. The degraded organic material was then further characterized using thermogravimetric analysis, elemental analysis, FT-IR spectroscopy, and the total content of water-extractable polyphenolic substances in the samples was also determined.
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Study and characterization of organic substances in a biochar sample
Vojáčková, Beáta ; Kalina, Michal (referee) ; Enev, Vojtěch (advisor)
This bachelor thesis characterizes biochar from a physico-chemical point of view. The theoretical part deals with biochar as a soil conditioner, its properties, use, production, and last but not least, effect of its sorroundings. For better characterization of organic and inorganic matter a phosphate buffer was used. This buffer ensures their specific extraction due to a neutral pH. The second path is to use rainwater, which simulates the condition of the soil environment. In the experimental part are discussed both; purified buffer-extracted samples and rainwater samples, which were studied by thermogravimetric analysis (TGA), elemental analysis (EA) and by infrared spectroscopy with Fouier transform (FTIR-ATR). Conductivity and pH were also measured. Moisture and ash content, which represent the inorganic non-combustible fraction, were determined using thermogravimetry. The extraction yields were converted to ashless wt. % based on these values. Results of EA provided us with information on the content of biogenic elements and basic physico-chemical characteristics of biochar. In contrast, the FTIR method defined the presence of individual functional groups and specific constitutive units, which are present in the extracts. This information allows us to better understand the environmental impact of biochar on the soil ecosystem.
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Optimization of the Methodology for Assessment of Biochar Effect on the Growth of Model Plants
Štorková, Natálie ; Enev, Vojtěch (referee) ; Kalina, Michal (advisor)
This bachelor thesis is studying the effect of biochar on the growth of model plant and deals with the optimalization of the methods for assessing its impact. Theoretical part describes the properties and utilization of soil conditioners, special attention is focused on biochar. According to the literature research, maize (Zea mays) was chosen as a model plant for cultivation experiment and subsequently the application doses of biochar were also defined. The cultivation experiment took place in growing box under controlled illumination and irrigation. Plant dry weight weighing after cultivation, continuous measurement of plant height during the cultivation and also image analysis of the root system were used for evaluating the influence of biochar on quantitative and qualitative properties of model plants. From obtained data it can be summarized that the growth differences were influenced by the application dose, the type of biochar and also by type of soil, which was used for the cultivation experiment.
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Use of thin layer chromatography for fractionation and characterization of organic matter isolated from alginite
Solanský, Pavel ; Sovová, Šárka (referee) ; Enev, Vojtěch (advisor)
This diploma thesis is focused on the study of structure and physicochemical properties of organic fractions of humic substances, which were obtained by the method of thin-layer chromatography. Humic substances, which were used in this study, were isolated from a sample of Slovak alginite based on the procedure of the International Humic Substances Society (IHSS). The following analytical techniques were selected for the characterization of isolated humic substances: thermogravimetric and elemental analysis, molecular absorption spectroscopy (UV/Vis), Fourier transform infrared spectroscopy (FTIR) and steady-state fluorescence spectroscopy. Each organic fraction of humic substances were characterized by molecular absorption spectroscopy (UV/Vis) and steady-state fluorescence spectroscopy. Using steady-state fluorescence spectroscopy, humic substances were found to be composed of fluorophores of humic and non-humic (protein) character. Organic fractions corresponding to the humic fluorophores were characterized by a higher content of oxygen substituents on the aromatic nukleus, a higher degree of aromaticity and also a higher molecular weight. The aim of this diploma thesis was to design and optimize the process of organic matter fractionation for the purpose of detailed understanding of the structure and properties of humic substances, which were isolated from the sedimentary rock alginite. Based on this, the practical applicability of the thin layer chromatography method to significantly reduce the molecular heterogenity of the studied humic substances was evaluated.
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Distribution of the Organic Matter in a Sample of Biochar
Novotný, Maximilián ; Enev, Vojtěch (referee) ; Kalina, Michal (advisor)
This bachelor’s thesis is focused on characterization of the content and distribution of organic matter in a sample of biochar. For these purposes, the organic matter from a biochar sample was isolated using two procedures, specifically sequential chemical fractionation, and alkali extraction. Prepared samples were characterized by elemental analysis and thermogravimetry. Analysis results showed that sequential chemical fractionation brings higher yields than alkali extraction, moreover, it provides more detailed image of organic matter in biochar thanks to obtained separated fractions according to their linkage to the original biochar matrix. Secondly, studied biochar has a great potential as soil supplement, it contains almost 70 % of organic carbon, whilst isolated amount, which is available represent only small amount, the rest is strongly bound. On the other hand, the study showed that this specific biochar has rigid structure, which brings benefits in the context of using biochar in agriculture in long-term consideration.
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Study on the Effect of Biochar Application on Organic Matter in Soil
Kurková, Marie ; Sovová, Šárka (referee) ; Kalina, Michal (advisor)
This bachelor thesis studies the effect of the application of biochar on the composition of organic matter of two different soil samples. Specifically, the total content of organic matter in the soil and the ratio of humic and fulvic acids in these soils before and after the application of biochar were monitored. The composition of the soil mass was also observed thermogravimetrically and by using the certified method of humic and fulvic acids isolation from samples of studied soils. Furthermore, the effect of biochar on the growth of a model plant (maize – Zea mays) was observed. From this point of view, differences in plant growth were possible to observe from the beginning of the experiment, both in comparison with samples with and without biochar and in comparison with samples containing different doses of biochar. The type of soil used for cultivation experiments also influenced on plant growth.
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Genetic potential for methane metabolism in the Greenland subglacial ecosystem
Rybár, Marek ; Stibal, Marek (advisor) ; Šabacká, Marie (referee)
Subglacial environments, located at the interface of glacier ice and bedrock, represent one of the major ecosystems associated with glaciers and ice sheets. This environment contains liquid water and underlying sediment with large amounts of organic matter overridden during periods of ice advance. Large areas of subglacial sediment are exposed annually by glacier melting and retreat, which affects the subglacial carbon stores and may significantly impact regional carbon fluxes. Due to the widespread anoxia at glacier beds, subglacial environments are potential producers and reservoirs of methane that can be released into the atmosphere as a consequence of glacial retreat. While the presence of methanogens and methane oxidisers has been shown based on 16S rRNA gene data, no data on the functional genetic potential for methane metabolism currently exist. In this study, the first subglacial metagenomes obtained from subglacial sediment exported from beneath the Greenland ice sheet by a meltwater river were used to characterize the metabolic potential for methane metabolism by the identification and quantification of genes involved in methane production and consumption. Functional genes of potential syntrophic pathways were also investigated. Functional genes of methanogenesis/anaerobic oxidation of methane and...
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