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Zhodnocení vybrané "správné zemědělské praxe" ve vybraném provozu s chovem skotu
POSPÍCHAL, Lukáš
This thesis deals with the topic of airpollutin caused by the greenhouse gases and ammonia which rises by cash breeding of dairy cows. Worldwide agriculture is considered as one of the biggest producer of ammonia. The thesis describes the environment and its components, law and legislation connected with this topic. The second part of the thesis deals with the measured and evaluated gases. The measurement took place at a collective farm in Skalka (farm Lipí), where dairy cows are bred. Both - the main measuring device and the distributor of consumption spots were supplied by the company INNOVA. Last part of the thesis mentions the ways how to reduce the stable gases production.
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Pěstování Silphium perfoliatum L. pro energetické účely a hodnocení produkčních schopností
MALINA, David
The subject of this study is "Cultivation of Silphium perfoliatum L. for energy purposes and evaluation of production capacities". One of the most important renewable energy sources is the energy of phytomass. Recently there has been a significant development of the cultivation of energy plants, as a raw material for biogas production in biogas stations in the conditions of the Czech Republic is mainly a maize. Cultivation of maize is in many ways undesirable. It carries with environmental problems associated, for example, with water erosion. One of the ways to solve these problems is to replace maize with other plants suitable for these purposes. A possible alternative is the cultivation of multi-annual energy plants. One of them is also the Silphium perfoliatum L., which is sporadically cultivated in the Czech Republic. The aim of this study is to evaluate the production capabilities of the Silphium perfoliatum L. and to evaluate the possibilities of his introduction as an alternative in the cultivation of maize sets.
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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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Testování zbytkové produkce bioplynu z fermentačních zbytků
Havelka, Kamil
This diploma thesis is focused on testing residual biogas production from fermentation residues. This thesis is divided into two parts - theoretical and practical. Theoretical part is divided into few chapters. At first I will explain basic consepts such as principle of the generation of biogas, the formation of biogas fermentation residue by dividing the output of biogas plants, waste fermination residue etc. The practical part is based on theoretical knowledge. Practical part contains actual testing of residual biogas production from fermentation residues and results of this testing.
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Aktivita a výskyt metanotrofních bakterií v povrchových vodách řeky Labe
MATOUŠŮ, Anna
During this PhD. thesis, the importance of methane-oxidizing bacteria (methanotrophs) and their ecological demands were studied on the longitudinal transect along an important European river - the River Elbe. However, it was necessary to adjust methodologies for precise measurements of methane oxidation in such a variable aquatic environment. Based on laboratory experiments and field measurements, several key methodological recommendations for future planning of methane oxidation rate estimations in an unknown environment have been identified or specified. In line with the variability of the river habitats, considerable heterogeneity was also found in the obtained data on methane concentration and methanotrophical activity. Probably, some of the most important information gathered during many field sampling campaigns is that sites with the highest methane concentration usually showed a very low activity of methanotrophic bacteria (resulting in higher methane emissions). These sites are predominantly human modified sections of the river, such as locks, weirs, harbors and canals. On the contrary, the free-flowing parts of the river, modified only by groynes, showed low level of methane concentration. And so groynes could represent a more effective solution and "natural-close" habitats of navigability of rivers.
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Wood ants of genus Formica as important ecosystem engeneers
Jílková, Veronika ; Frouz, Jan (advisor) ; Tajovský, Karel (referee) ; Bonkowski, Michael (referee)
This thesis consists of one chapter accepted for publication in a book and four papers published in international journals with impact factors. All of the contributions deal with the role of wood ants in energy and nutrient fluxes in forest ecosystems. Wood ant nests are known as hot spots of carbon dioxide (CO2) production and are also thought to affect methane (CH4) flux. Stable high temperatures are maintained in ant nests even in cold environments. This study is focused on quantification of CO2 and CH4 flux in wood ant nests, contribution of ants and microbes to CO2 production, properties of nest material that affect CO2 production and the role of ants and microbes in the maintenance of nest temperature. The research was conducted in temperate and boreal forests inhabited by wood ants (Formica s. str.). Gas fluxes were measured either by an infrared gas analyser or a static chamber technique. Ants and nest materials were also incubated in a laboratory. Material properties potentially influencing CO2 flux, such as moisture, nutrient content or temperature were determined. According to the results, CH4 oxidation was lower in wood ant nests than in the surrounding forest soil suggesting that some characteristics of ant nests hinder CH4 oxidation or promote CH4 production. Wood ant nests clearly are hot...
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Freshwater wetlands as a biogeochemical archive: Temporal changes in climate and environmental records
Zemanová, Leona ; Novák, Martin (advisor) ; Mihaljevič, Martin (referee) ; Hojdová, Marie (referee)
Worldwide, peatlands cover an area of 4.106 km2 . Plant primary production dominated over organic matter decomposition and enabled organic matter to accumulate during the last 11 000 years. Peatlands represent a reservoir of atmospheric carbon and they are a useful scientific tool for reconstructions of historical atmospheric pollution. The first part of the thesis focuses on peatlands as a dynamic carbon reservoir under predicted climate change that would influence carbon cycling and emissions of greenhouse gases into the atmosphere. Three methodological approaches were used - a mesocosm laboratory incubation, a transplant experiment and in situ gas flux measurements. The laboratory incubation studied the response of peat samples from temperate (Velké Dářko, Czech Republic) and boreal (Stor Åmyran, Sweden) zone to a temperature increase, water table decrease and their combination. Today, the warmer site exhibits ~14 times higher CH4 production potential than the colder site (28 mg m-2 hr-1 at VD, and 2 mg m-2 hr-1 at SA). Both sites respond differently to temperature increases. Changes in methane production were up to 9 fold due to different temperatures. A gradual decrease of water table level from 2 to 14 cm below the peat surface had a much stronger effect, VD exhibited a decrease in methane...
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Formation of organics molecules initiated by high-power density energy events in planetary atmospheres
Kamas, Michal ; Civiš, Svatopluk (advisor) ; Zelinger, Zdeněk (referee)
The focused laser beam delivered by the high-power laser system PALS was used for laboratory simulation of high-energy-density events in a planetary atmosphere. Several model gas mixtures were prepared to mimic the mildly reducing early Earth's atmosphere (CO-N2-H2O) as well as the atmosphere of Saturn's moon Titan and the strongly reducing early Earth's atmosphere (CH4-N2-H2O). In situ investigation of transient species generated by the laser-induced dielectric breakdown in the gaseous mixtures was performed by optical emission spectroscopy (OES). Final products of laser-plasma initiated chemical reactions were identified and determined by advanced mass-spectrometry (SIFT-MS) and absorption FT-IR spectroscopy. High-power laser system SOFIA was utilized to simulate in our laboratory a high-velocity impact into the icy satellites of the outer planets of the Solar system. OES was engaged in probing the plasmas produced by the SOFIA beam focused on ice surfaces (water, methanol, formamide), while final products were analyzed by means of gas chromatography (GC/MS) and mass-spectrometry (SIFT-MS).
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Emise skleníkových plynů ve vztahu k mikrobiální aktivitě a obsahu živin arktických půd
HAJŠMANOVÁ, Klára
The aim of this study was to understand the link beween greenhouse gasses emissions (CH4 and N2O) microbial activity and nutrient content in soil from different types of soil in Svalbard. Warming can cause release of large amounts of carbon and nitrogen in form of greenhouse gasses from soil into the atmosphere. This might strengthen the greenhouse effect and thus global climate change. We measured release of greenhouse gases from soil. At the same time, soil sampling was conducted at five different localities in August in the years 2014 and 2015. Soils were found to have low nutrient content and unfavourable C/N ratio to support vegetation growth. Areas were not a significant source of emissions of greenhouse gasses from soil to the atmosphere.
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Climate change caused by volcanic eruptions
Kolářová, Iveta ; Vokoun, Martin (advisor) ; Soukupová, Jana (referee)
This Bachelor thesis is engaged in climate changes caused by volcanic eruptions and explains, why after major volcanic eruptions follow volcanic winters. The first chapter shows the formation of volcanic activity and relations to climate changes. In three parts of the second chapter are described sectional factors (solar activity, problems of ocean currents and at-mospheric flow) to climate changes. In the third chapter are mentioned issues of science discipline of paleoclimatology and historical climatology, which combines a lot of disciplines as a geology, botany, zoology and more. The fourth chapter presents the main part of the work, because in this part is a description of the selected major volcanic eruptions of the last millennium and their consequences in the period after an explosion from the viewpoint of abnormalities in the weather. In conclusion of the Bachelor thesis is a search for an answers to question: Risks of powerful eruptions in the future and their impact on the human population.
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