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Effect of different water regime on microorganisms of nitrogen cycle in permafrost
TURKOVÁ, Sára
The gene abundances and community structures of nitrogen-fixing and denitrifying bacteria in permafrost-affected soils with different moisture level were analysed. Additionally, DNA- and RNA-based analysis was used to evaluate the variations in gene copy numbers and community composition between the total and active bacteria. The gene abundances of nitrogen-fixing and denitrifying bacteria were quantified by qPCR of the nifH and nosZ genes, and the gene copy numbers were compared between the soils with different moisture. Furthermore, the bacterial community structure variation was evaluated by analysis of the taxonomic classification obtained from sequencing data.
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Atmospheric deposition of nitrogen - application of stable isotopes
Hanzlová, Barbora ; Hůnová, Iva (advisor) ; Hovorka, Jan (referee)
Human impact on particular parts of ecosystems has become a highly discussed topic. Due to different isotopic values of nitrogen, it is possible to evaluate the extent to which human influences the natural nitrogen cycle, using isotope measurements. Stable isotope measurement has been used in various scientific disciplines around the world. This thesis summarizes the findings about atmospheric deposition and the subsequent use of stable nitrogen isotopes. The objective of this work was to gather the information about the use of stable isotopes in the study of the atmospheric deposition and how to make better use of the information obtained from the measurements. Based on the literature review, it has been found that, unlike other countries, nitrate substances such as NH3 and HNO3 are not measured in the Czech Republic, which distorts the data on the nitrogen produced. The use of stable isotopes is a convenient method of measuring both not yet quantified substances as well as already measured substances contributing to atmospheric deposition. The stable isotope measurement method represents an improvement for the overall estimation of atmospheric deposition to provide more realistic values compared to the current approach. Key words: atmospheric deposition, nitrogen, stable isotopes
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Atmospheric deposition of nitrogen - application of stable isotopes
Hanzlová, Barbora ; Hůnová, Iva (advisor) ; Hovorka, Jan (referee)
Human impact on particular parts of ecosystems has become a highly discussed topic. Due to different isotopic values of nitrogen, it is possible to evaluate the extent to which human influences the natural nitrogen cycle, using isotope measurements. Stable isotope measurement has been used in various scientific disciplines around the world. This thesis summarizes the findings about atmospheric deposition and the subsequent use of stable nitrogen isotopes. The objective of this work was to gather the information about the use of stable isotopes in the study of the atmospheric deposition and how to make better use of the information obtained from the measurements. Based on the literature review, it has been found that, unlike other countries, nitrate substances such as NH3 and HNO3 are not measured in the Czech Republic, which distorts the data on the nitrogen produced. The use of stable isotopes is a convenient method of measuring both not yet quantified substances as well as already measured substances contributing to atmospheric deposition. The stable isotope measurement method represents an improvement for the overall estimation of atmospheric deposition to provide more realistic values compared to the current approach. Key words: atmospheric deposition, nitrogen, stable isotopes
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Atmospheric deposition of nitrogen - application of stable isotopes
Hanzlová, Barbora ; Hůnová, Iva (advisor) ; Hovorka, Jan (referee)
Based on the literature review, the thesis summarizes the use of stable isotopes in the atmospheric deposition. According to the studies and empirical research, the origin and the extent of the pollution in the environment can be tracked down. Due to the different isotopic values, it is possible to evaluate the extent of human impact on the natural cycle of the ecosystem. Nitrogen can be found in all nature constituents where it gains different isotopic values. The objective of this work was to gather the information about the stable isotopes and to prove whether they are reliable indicators in determining the source of the nitrogen in the given area. By using the evaluated study, the difference in pollution within the coastal and continental areas in Central Europe was described. Keywords: atmospheric deposition, nitrogen cycle, stable nitrogen isotopes, fractionation
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Effect of eutrophication of environment on transformation and leaching of nitrogen from soil to water
KOFROŇOVÁ, Iveta
The master thesis lists the basic effects of nitrogen transformation in soil (nitrification), subsequent leaching of nitrates from soil to water and the effects of eutrophication of aquatic environment on the human health. The results of this experiment show that the interaction of all three factors (fertilization, soil moisture, vegetation) has a significant effect on the rate of nitrification. Generally, the nitrification rate increases with fertilization, decreases with presence of vegetation and decreases with soil moisture decrease. The health risk of nitrates in water consists in their consumption and the subsequent development of methemoglobinemia (especially in young infants) and the formation of N-nitroso compounds (e.g.nitrosamines), which have carcinogenic and teratogenic effects. Nitrate together with phosphates also promote the growth of cyanobacteria and algae. Cyanobacteria can produce cyanotoxins causing several groups of diseases.
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