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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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Ecotoxicological assessment of biochar from sewage sludge
Kotzurová, Iveta ; Vávrová, Milada (referee) ; Zlámalová Gargošová, Helena (advisor)
The aim of this diploma thesis is to assess the ecotoxicological effect of biochar produced from sewage sludge. In case of application of biochar to agricultural land, both the soil and aquatic ecosystem may be affected therefore contact and aquatic tests were chosen to assess the ecotoxicological effects. Representatives of soil invertebrates were earthworms Eisenia fetida; Daphnia magna and Artemia salina were chosen from aquatic animals and terrestrial plants were represented by Lactuca sativa, Sinapis alba and Allium cepa. The results of contact tests point out how ecosystem could be negatively affected by biochar dose. Through aqueous extract were shown differences in sensitivity of individual organisms in aquatic tests. Dried sewage sludge was found to be the biggest burden for all tested organisms. The pelletized biochar with the addition of an additive showed the lowest negative effect on tested organisms.
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Preparation and Characterization of Biochar - the Effect of Pyrolysis Conditions and the Source of Used Biomass
Novotný, Maximilián ; Pořízka, Jaromír (referee) ; Kalina, Michal (advisor)
This diploma thesis is focused on preparation of biochar samples, which were characterized to reveal influence of preparation conditions on biochar properties physical-chemical properties. Preparation conditions covered temperature range of 400 °C to 700 °C and 2 different residence times were used. Biochars from each source biomass has its own characteristics, however the similiarities between biochars from different sources were found. Biochar yields were specified and the minimum yield was at least 24 %. Analysis on content revealed, that oat brans, mixed wood and corn residue contain a lot of organic matter, relatively, and also contains a lot of organic carbon. Results of structural analysis confirmed individual structural properties, porosity and content of function groups in particular. Influence of higher pyrolysis temperature results in slightly lower yields, however it provides products with higher content of organic carbon and higher surface area, in majority of cases. Subsequently, it was found out that short residence time of 10 minutes does not have to be enough for all used biomasses. On the basis of gained data, the preparation or production can be optimalized in effort to make usage of residue biomass more effective in different application, not only in agronomy sector.
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Study of sorption properties of biochar
Kocinger, Oskar ; Řezáčová, Veronika (referee) ; Mravcová, Ludmila (advisor)
This diploma thesis deals with sorption properties of biochar produced from wood biomass treated with concentrated hydrochloric acid and activated carbon with respect to the triazine pesticide propazine. Although pesticides are widely used in both agriculture and the private sector worldwide, they pose a significant risk to ecosystems and human health. Propazine belongs to the group of chlorinated triazine herbicides, which pose a risk mainly as endocrine disruptors. The sorption of organic pollutants using pyrogenic carbonaceous materials promises an efficient and economically affordable solution, which has recently received increasing attention from the scientific community. In this work, we used isotherms to describe the equilibria of propazine sorption to given sorbents during vial experiments. Analysis of the propazine content in the model water solutions after reaching equilibrium was performed using high-performance liquid chromatography with mass detection.
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Biochar Effect on the Microbial Processes in Soil
Losová, Anežka ; Sovová, Šárka (referee) ; Kalina, Michal (advisor)
This bachelor thesis is focused on the investigation of the biochar effect on the microbial processes in soil. The theoretical part describes the properties of the soil, the characteristics of biochar, the definition of the methods of its production and the influence of biochar on microbial activity in soil. The experimental part was focused on optimization of the conditions for assessing of the effect of biochar on the rate of mineralization of soil organic matter through monitoring of the release of carbon dioxide from soil without biochar and from the biochar-amended soil with NPK fertilizer. Carbon dioxide was sorbed into sodium hydroxide during the incubation and the released amount was determined by titration. In the following part of the thesis, the experiments were focused on assessing the effect of increased soil temperature and humidity on the amount of CO2 released by soil respiration. Experimental data showed that biochar promoted the microbial activity and this effect was even enhanced by addition of NPK fertilizer to a defined amount of biochar. The increased temperature negatively influenced the microbial processes in soil, as the rate of soil respiration of carbon dioxide decreased. Excessive moisture had also a negative effect on microbial activity, resulted in the slowed rate of the soil respiration. In summary, biochar has a positive effect on microbial activity and the rate of mineralization of soil organic matter in a defined amount under the appropriate conditions and it can be used as a suitable soil conditioner in agriculture.
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The Influence of Microbial Degradation of Biochar in Soil on its Physico-chemical Properties
Kurková, Marie ; Weidlich, Tomáš (referee) ; Kalina, Michal (advisor)
This master‘s thesis studies the different factors that can affect biochar in soil and cause its degradation. These factors include irrigation, root exudates and the action of microorganisms. In the experimental part, the degradation of biochar in the soil environment was studied in two ways, firstly without the action of microorganisms, where the effect of irrigation was simulated by leaching biochar in ultrapure distilled water and model rainwater, and the effect of root exudates was simulated by extracting of biochar in citric acid as a model root exudate of maize sown. The extracted biochar solutions without prior cultivation in soil were characterized by pH, conductivity, UV-VIS analysis and elemental analysis. The biochar residues after extractions were characterized for morphology by SEM, structural differences by FTIR, and organic and mineral content by TGA analysis. The biochar samples after cultivation in soil were subjected to extractions under the same conditions and the same analyses were performed. The effect of cultivation in soil on biochar resulted in a change in elemental composition, a decrease in biochar alkalinity and changes in the ratio of organic matter and mineral fraction were observed. The decrease in pH and conductivity of biochar was mainly related to potassium leaching. The structural and morphological analysis indicated that there is no significant degradation of the structure of the biochar due to washing or cultivation in soil, but there is a partial fouling of the biochar pores by low molecular weight impurities from the soil. These results suggest a short-term action of biochar in soils as a source of nutrients (potassium, phosphorus) and, conversely, a long-term action as a soil conditioner.
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Use of various extraction techniques for the analysis of biochar extracts
Jakubčeková, Kristína ; Řezáčová, Veronika (referee) ; Mravcová, Ludmila (advisor)
Biochar is a material whose properties, composition and impact on the environment are often discussed nowadays. The reason is its application as a soil conditioner. This leads to the need for qualitative as well as quantitative knowledge of its composition. This diploma thesis focuses on the qualitative analysis of biochar leachates processed by various extraction techniques. To approximate the real conditions, six aqueous mediums with different pH values is used, which a solid sample of biochar is exposed to. The prepared leachates are after that processed by extraction techniques, which are solid phase microextraction (SPME), single drop microextraction (HS-SDME), solid phase extraction (SPE) and liquid-liquid extraction (LLE). Analysis of the extracts was performed by gas chromatography-mass spectrometry (GC/MS). The measurements showed that the HS-SDME technique did not show a response. SPE was a rapid technique, but compared to other techniques, it acquired a smaller range of substances. Liquid-liquid extraction, a time-consuming technique, did not obtain as much analytes as SPME. By comparing these applied techniques, the SPME technique is the best choice. The most common determined analytes were those from the group of ketones and carboxylic acids and their derivatives.
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Analysis of biochar aqueous extracts by separation methods
Tučková, Dominika ; Čáslavský, Josef (referee) ; Mravcová, Ludmila (advisor)
This master's thesis deals with the analysis of biochar extracts by separation methods. All analyzed biochar was produced from waterworks sludge by microwave pyrolysis. The aim of the thesis is the optimization of the sample preparation method and its analysis in a laboratory environment. With the ever-growing world population, the problem of a sustainable economy in both agriculture and waste management is becoming increasingly urgent. This fact has led most countries to consider promoting the so-called Circular Economy. The use of sewage sludge as a feedstock for biochar production is perfectly in line with this strategy. So far, however, the short term and the long term benefits and risks of using biochar have not been sufficiently described. Potentially hazardous organic substances were extracted from the biochar extracts by three techniques: liquid-liquid extraction, solid-phase extraction, and solid- phase micro-extraction. The obtained samples were analyzed using the GS-MS/TOF method. The individual methods were compared. Several biochar samples from WWTP Brno and WWTP Drahovice were selected and analyzed to verify the suitability of the selected sample analysis method.
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Characterization of organic substances in biochar and their release in the soil ecosystem
Bočán, David ; Doležalová Weissmannová, Helena (referee) ; Mravcová, Ludmila (advisor)
The aim of this master’s thesis was to optimize the extraction of 38 PAH and 7 PCB compounds from samples of commercially available biochar and then apply the most suitable extraction method to real samples of biochar and soil. The concentrations of mentioned compounds were determined by using gas chromatography with mass spectrometry detection. Finally, from these concentrations in individual samples, a rate of release of these compounds from biochar to soil was determined. The theoretical part was focused on summarizing the process of biochar production and its properties. The next part deals with compounds that can be present in biochar, their physicochemical properties and effects on organisms and the environment. Also, a most common ways of extracting and determinating these compounds are mentioned. The final part focuses on soil and its characteristics and the changes it undergoes when biochar is applied to it. In the practical part an extensive optimization of extractions using a PSE extractor and thermal desorption extraction was conducted. After determining optimal conditions for both types of extraction methods, these methods were applied to real samples of biochar and soil. Qualitative analysis was carried out using GCxGC-TOF mass spectrometer and quantitative analysis by MRM method on GC-MS2 mass spectrometer.
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Revitalizace zemědělských půd
Vavřina, Jan
From the beginning of agriculture, an important soil-forming factor begins to take shape, and that is man. Human activity changes soil properties in favor of only one soil function, and that is plant growth (production, yield). However, these changes reduce the variability of soil properties, which are subsequently degraded and thus further disrupt the entire agroecosystem. New procedures, principles and agrotechnical measures that help to revitalize the soil are gradually being implemented across the world. These changes in the way agricultural land is managed take advantage of mutual ecological interactions that help to fulfill basic soil functions and provide ecosystem services. In the practical part of the work, two soils with different degrees of revitalization were compared. These soils were compared in relative values to the control soil, which was little affected by agricultural activities. The results show that agricultural soils have a lower stability of soil aggregates, bulk density, ammonium form N content, and SOM content compared to the control soil. At the same time, however, a higher respiration rate was recorded, which was influenced by tillage by taking soil samples.
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