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Influence of ants on soil chemistry across biomes
Kostečka, Luboš ; Frouz, Jan (advisor) ; Jílková, Veronika (referee)
Ants are important ecosystem engineers. Their activity has direct and indirect influence on soil chemistry inside their nest through processes such as bioturbation or accumulation of organic matter and its decomposition by the microbial community. These processes depend on environmental conditions such as soil properties and climate. However, there has not yet been a comparison of this influence on soil chemistry across different biomes. The aim of this thesis is therefore (1) describe the processes through which ants influence soil chemistry (2) summarize the resulting influence on soil properties such as the concentration of nutrients and the pH level in the ant nests and the surrounding soil (3) find out whether there is a common trend to these influences across biomes, or if every biome has its own specific trend. The findings of this thesis point to the conclusion that while there is a common trend across biomes, it heavily depends on conditions such as nest structure, feeding strategy of a particular species and the climatic conditions of the given ecosystem. Key words: ants, soil, soil chemistry, biomes, nests, bioturbation, feeding strategy, macronutrients, pH, environmental conditions, climate
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Automatic hydroponic microfarm for plant cultivation
Takács, Peter ; Janoušek, Jiří (referee) ; Szabó, Zoltán (advisor)
This thesis deals with the implementation of hardware and software design for an existing hydroponic micro-farm. The thesis includes a literature and internet search focused on automated plant cultivation. A description of different types of soilless cultivation systems is given in the thesis. General plant requirements are addressed and these requirements are thoroughly discussed. Instrumentation using specific components is also described in the thesis. The system integrates a control unit, heating and aeration controls for the nutrient solution, adjustable lighting, and sensors for pH, EC, and adjustable water and ambient temperature. In addition, the advantages and disadvantages of two selected microprocessor units are discussed. Further, the operation of the microcontroller that controls the individual components is also described in the thesis. This thesis briefly describes the general circuitry of each component and includes circuit diagrams and the schematic of a printed circuit board. This thesis describes the program of the firmware and the functions of the web interface used to interact with the system. Additionally, it features remote control and monitoring capabilities via a web interface, with email alerts for external intervention needs. This thesis also includes the implementation of the electronics in terms of assembly and calibration.
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Influence of content of organic matter and calcium on immobilization of pharmaceuticals in soil
Kotradyová, Viktória ; Sedláček, Petr (referee) ; Klučáková, Martina (advisor)
This thesis aimed to highlight the problem of antibiotics and their presence in nature, particularly tetracycline. High global consumption, limited metabolism in the body and incomplete degradation in wastewater treatment plants represent the reasons why pharmaceuticals have been found in the environment. Their presence might have a negative impact on the natural ecosystem, including humans. Therefore, addressing their behaviour and finding solutions for their removal from nature seems important. The soil itself has a self-cleaning capacity, which may immobilise these pollutants into organic structures to prevent their subsequent migration. The presence of inorganic cations in soil plays an essential role in the sorption process of antibiotics. Calcium ions from the soil with whom the tetracycline forms chelate complexes, should be also taken into account. Regarding the practical part, tetracycline interactions with soil systems were studied in both sorption and desorption experiments. Four soils with different amounts of organic matter and calcium have been examined. Tetracycline was extensively adsorbed to all four soils. Desorption processes showed low efficiency and refer to stable adsorption onto soil. The experimental data were fitted by Freundlich and Langmuir isotherms, where the second mentioned is suitable for three of the four soils. Subsequently, sorption and desorption experiments were conducted in four different pH buffers (3, 5, 7 and 10). The effect of pH on sorption was not significant, however during desorption at lower pH higher desorbed levels of tetracycline were observed. Photodegradation of tetracycline in solution was investigated to determine the rate of degradation of tetracycline on light, where the results indicated that the concentration decreased by 22 % after 29 days compared to the applied concentration. Quantitative analysis was carried out using UV-VIS spectroscopy and liquid chromatography. In addition, the soil spectra of the FTIR were measured to obtain information on the sorption mechanism
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Monitoring of physico-chemical parameters on selected fisponds of the Vrbenské system
NEUŽIL, Tomáš
The aim of the bachelor's thesis was to measure selected physical and chemical indicators and then compare them with measurements that were carried out in previous years at individual ponds of the Vrbenské system near the statutory city of České Budějovice. Measurements took place at monthly intervals in the morning from April to September 2023. The measured physical parameters were water temperature and transparency. The measured chemical parameters were pH, O2 saturation in the water column and electrical conductivity.
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Funkční a patologické změny žaludku hostitelů reinfikovaných různými druhy a genotypy žaludečních kryptosporidií
MARKOVÁ, Marie
Representatives of the genus Cryptosporidium are intracellular parasites from the phylum Apicomplexa that parasitise the gastrointestinal tract of vertebrates. Within the genus, the species are divided into two groups depending on the site of infection: intestinal and gastric cryptosporidia. Infection with intestinal species is associated with watery diarrhoea, while infection with gastric species is usually asymptomatic. However, studies have indicated histopathological changes in gastric tissue during infection with these species. This work focuses on the influence of infection and reinfection with Cryptosporidium proliferans and Cryptosporidium muris CAT21 on gastric pH, morphological and pathological changes of the gastric mucosa in experimental mastomys and the mouse strains BALB/c and C57Bl6. In mice infected with C. muris CAT21, an increase in stomach pH was observed only after the primary infection; during reinfection, no increase in pH was observed on any of the days observed. In both groups, an increase in mucosal thickness was observed during infection, but was not as pronounced in BALB/c mice during reinfection as during primary infection. In C57Bl6 mice, reinfection resulted in a slight thickening, but no significant peak was observed and mucosal thickness remained similar. Inflammatory infiltrates were present in the tissue of both BALB/c and C57Bl6 mice during both infection and reinfection. Reinfection with C. proliferans led to an increase in gastric pH in both BALB/c and C57Bl6 mice. Although morphological changes were observed after reinfection, they were less pronounced. The results indicate that reinfection can influence the immune response and gastric morphology, but does not cause significant changes in pH. In addition, the influence of acidic water administration on the course of C. proliferans infection was investigated. No significant differences in the course of infection and pathological changes were observed between groups of mastomys supplied with acidic and tap water and infected with C. proliferans.
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Vliv teploty a času na excystaci Cryptosporidium muris izolát CAT21
DUDÁKOVÁ, Hana
The main aim of this master's thesis was to investigate the impact of environmental pH and the host's body temperature on the excystation of Cryptosporidium muris oocysts. The experiment utilized the CAT21 isolate obtained from a naturally infected domestic cat (Felis catus f. domestica), although rodents are the primary hosts of Cryptosporidium muris. The isolate was continuously maintained in immunodefi-cient SCID mice, from which fecal samples were regularly collected for individual experiments. The first factor examined for its influence on oocyst excystation was the host's body temperature. Oocysts stored in dH2O were subjected to water baths set to temperatures ranging from 21 to 44°C for durations of 5, 15 and 30 minutes. According to the results, the optimal temperature for excystation of C. muris CAT21 oocysts was 37°C for a duration of 30 minutes, resulting in up to 92% excystation. Additionally, the study included an examination of the pH impact on excystation. Oocysts were exposed to PBS solutions with varying pH values (ranging from 2.00 to 9.00) and heated in a water bath at 37°C. The optimal pH for excystation was found to be 6.00, with up to 93% excystation observed. The viability of the oocysts used was determined by staining with propidium iodide before each measurement.
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Study of electrolyte influence on diaphragm discharge stability and efficiency
Němcová, Lucie ; Krčma, František (referee) ; Kozáková, Zdenka (advisor)
This thesis is focused on so-called diaphragm discharge, which is one kind of electric discharges in liquid, which belongs among so-called AOP´s techniques, still more used for water cleaning in the present. One of effectiveness and stability indicators of diaphragm discharge is generation of hydrogen peroxide. In theoretical part, detail principle description of electric discharge in liquid is situated. Further, properties of electrolyte are introduced and general spectrophotometric method of obtained sample determination is described. In experimental part, a full procedure of experiment is introduced. Next part containing results and discussions introduces particular results of individual measurements and their reasons. Final chapter is the end, which forms total summary and evaluation of all results. By the application of all chosen electrolytes in solution at diaphragm discharge formation of hydrogen peroxide has appeared. Inorganic and organic electrolytes were used. As inorganic electrolytes following salts were selected – solutions of halogenides, next sodium nitrate as a representative of nitrates, potassium dihydrogenphosphate as a representative of phosphates, etc. Representative of organic electrolytes was citric acid. The value of initial conductivity of electrolytes had the main influence on hydrogen peroxide formation. Electrolytes potassium dihydrogenphosphate and sodium sulphate the great influence on effectiveness and stability of the diaphragm discharge. Their rate constants reached maximum value by the application of solution with initial conductivity of approximately 400 mikrosiemens, particularly 0.0492 mmol/l.min and 0.048 mmol/l.min. On the contrary, low values of rate constant were achieved in electrolyte ammonium chloride at around the same initial conductivity – 0.0269 mmol/l.min. During experiments stainless steel and platinum electrodes were used. It was found that kind of electrode material hadn’t influence on generation of hydrogen peroxide. Hydrogen peroxide was formed only in the cathode space.
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Automated control of aquarium operation
Kejzlar, Radim ; Šteffan, Pavel (referee) ; Háze, Jiří (advisor)
This master´s thesis describes complete design and implementation of an automated system for the control of a common freshwater tropical aquarium with a keyboard and display. The thesis discusses the applicability of equipment in today's aquaristics of freshwater tropical aquariums with respect to the history and market offer. Thesis describes the complete design of the electrical, program and mechanical parts of the resulting system and electrically controllable automatic feeder, communicating with the system.
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Determination of selected nutritional parameters in the fruit of the plant genus Ribes
Ledvina, Vojtěch ; Diviš, Pavel (referee) ; Vespalcová, Milena (advisor)
This bachelor thesis focuses on the small fruit representatives from the plant genus Ribes L. - currant, gooseberry and jostaberry. The beginning of theoretical part describes history of cultivation and basic botanical description of individual cultivars. The next part describes important substances contained in fruit as well as their importance in human diet and it also describes some basic products made of the Ribes L. genus representatives. The final section of the theoretical part contains basic principal of determination of individual nutritional parameters. In the experimental part several nutritional parameters were determined including dry matter, soluble solids, pH, titratable acids, formol number, reducing sugars and total phenolics. Individual species and cultivars were compared based on the results.
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