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Natural sources and sinks of volatile chlorinated hydrocarbons in the spruce forest ecosystem
Štangelová, Pavla ; Tesařová, Eva (advisor) ; Pavlík, Milan (referee)
Biogeochemical cycle of chlorine, particularly the formation of organically bound chlorine is still not well understood. In continental ecosystems chlorides act as source of chlorine, and also as a stress factor. Chlorides originate from precipitation of marine cloud masses. Organically bound chlorine in the environment is formed naturally by biotical and abiotical way. The biotical factors are microorganisms, plants, soil enzymes and animals. Volatile chlorinated hydrocarbons (VOCl) represent one group of organically bound chlorines. Several volatile chlorinated hydrocarbons reacts with atmospheric ozone, consequently causing depletion of the ozone layer. The most important known terrestrial source of volatile chlorinated hydrocarbons is the spruce forest ecosystem. Chlorine in the soil can be transformed by microorganisms into organically bound chlorine or translocated by transpiration stream in plants, where they are also transformed enzymatically into organically bound chlorine, and both of them can be emitted into the atmosphere. Too large amounts of chloride can affect the physiological functions of plants. In this thesis experiments were designed for measuring the natural emissions of volatile halogenated hydrocarbons from plants and fungi, with various periods of incubation, and also to...
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Chlorophenols in the environment
Jíšová, Tereza ; Tesařová, Eva (advisor) ; Pavlík, Milan (referee)
Chlorophenols belong to major environmental pollutants and are characterized by their considerable toxicity, persistence and bioaccumulation. For their bactericidal and fungicidal properties have multiple uses. They are readily formed during water chlorination process and cause sensoric defects of drinking water. Thus they are posing a serious health hazard. Chlorophenols also occur in nature in minor amounts due to natural activity. The presence of chlorophenols in water samples is determined by various analytical methods. In this work, emphasis is placed on their determination by gas chromatography. The model assay was performed for 2-chlorophenol and 4-chlorophenol using derivatization and subsequent extraction with a final analysis by gas chromatography with electron capture detection. The limit of detection for 2-chlorophenol was 2.47 μg/l for 4-chlorophenol 3.14 μg/l. Key words: Chlorophenols, determination chlorophenols, degradation, toxicity
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The determination perimeter of the complex land consolidation in the cadastral area Dobronice
Matušková, Veronika ; Pavlík, Milan (referee) ; Berková, Alena (advisor)
The subject of this diploma thesis is the determination perimeter of the complex land consolidation in the cadastral area Dobronice. Documents for detection of borderlines are prepared on the basis of a defined perimeter. Borderlines of perimeter is examined with an officially appointed commission and with landowners. A geometric plan is made for the partition of the land, determination borderline of lands for land consolidation and running of specify borderlines from landowners. The results of detection borderlines are created in prescribed elaborate.
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Natural sources and sinks of volatile chlorinated hydrocarbons in the spruce forest ecosystem
Štangelová, Pavla ; Tesařová, Eva (advisor) ; Pavlík, Milan (referee)
Biogeochemical cycle of chlorine, particularly the formation of organically bound chlorine is still not well understood. In continental ecosystems chlorides act as source of chlorine, and also as a stress factor. Chlorides originate from precipitation of marine cloud masses. Organically bound chlorine in the environment is formed naturally by biotical and abiotical way. The biotical factors are microorganisms, plants, soil enzymes and animals. Volatile chlorinated hydrocarbons (VOCl) represent one group of organically bound chlorines. Several volatile chlorinated hydrocarbons reacts with atmospheric ozone, consequently causing depletion of the ozone layer. The most important known terrestrial source of volatile chlorinated hydrocarbons is the spruce forest ecosystem. Chlorine in the soil can be transformed by microorganisms into organically bound chlorine or translocated by transpiration stream in plants, where they are also transformed enzymatically into organically bound chlorine, and both of them can be emitted into the atmosphere. Too large amounts of chloride can affect the physiological functions of plants. In this thesis experiments were designed for measuring the natural emissions of volatile halogenated hydrocarbons from plants and fungi, with various periods of incubation, and also to...
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Chlorophenols in the environment
Jíšová, Tereza ; Tesařová, Eva (advisor) ; Pavlík, Milan (referee)
Chlorophenols belong to major environmental pollutants and are characterized by their considerable toxicity, persistence and bioaccumulation. For their bactericidal and fungicidal properties have multiple uses. They are readily formed during water chlorination process and cause sensoric defects of drinking water. Thus they are posing a serious health hazard. Chlorophenols also occur in nature in minor amounts due to natural activity. The presence of chlorophenols in water samples is determined by various analytical methods. In this work, emphasis is placed on their determination by gas chromatography. The model assay was performed for 2-chlorophenol and 4-chlorophenol using derivatization and subsequent extraction with a final analysis by gas chromatography with electron capture detection. The limit of detection for 2-chlorophenol was 2.47 μg/l for 4-chlorophenol 3.14 μg/l. Key words: Chlorophenols, determination chlorophenols, degradation, toxicity
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Hydrogen peroxide and the abiotic formation of chlorinated organic compounds in forest soil
Doležalová, Jana ; Forczek, Sándor Tamás (advisor) ; Pavlík, Milan (referee)
3 Abstrakt Peroxid vodíku je přirozenou součástí lesní půdy a vzniká především díky činnosti různých půdních organismů jako jsou houby rozkládající dřevo a mykorrhizní houby. Peroxid vodíku se v půdě účastní abiotické chlorace organických látek. Tato chlorace probíhá pravděpodobně pomocí Fentonové reakce: Fe2+ + H2O2 → Fe3+ + OH- + OH·. Vznikající hydroxylové radikály jsou schopny oxidovat chlorid na reaktivní HOCl a následně může proběhnout chlorace organických látek a vytváří se tak různé chlorované uhlovodíky. K měření H2O2 lze použít řady analytických optických, elektroanalytických či chromatografických metod. Cílem této práce byla optimalizace spektrofotometrické metody za použití xylenové oranže při stanovení H2O2 v lesní půdě. Tato metoda je spolehlivá, přístojově nenáročná, čas analýzy poměrně krátký. Metoda je vhodná k měření nízkých koncentrací hydroperoxidů ve vodě, ale pro půdní vzorky prozatím nebyla použita. Protože je matricí při této analýze půda, je vhodné užití metody standardního přídavku. Pro stanovení koncentrace z půdy byla přezkoušena také různá extrakční činidla, kdy se jako nejvhodnější ukázal aceton. Limit detekce peroxidu je 0,29 g H2O2/g půdy (n=8) a metoda je lineární až do hodnot 10 g H2O2/g půdy při čemž množství peroxidu v čerstvých jarních vzorcích půdy se pohybovalo od 2,5...
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Changes in cytokinin contents and metabolism in spinach in response to zinc excess in soil
Žižková, E. ; Gajdošová, Silvia ; Pavlíková, D. ; Pavlík, Milan ; Száková, J. ; Motyka, Václav
Changes in endogenous cytokinin (CK) contents and metabolism in spinach (Spinacia oleracea L.) responding to excessive amounts of zinc in soil were studied. Application of three zinc rates in soil (250, 500, 750 mg.kg-1) resulted in a progressive (1.7- to 3.3-times) increase of endogenous CKs in spinach leaves. This increase was predominantly due to accumulation of inactive and storage CK forms (N- and O-glucosides) and was accompanied with an enhanced activity of cytokinin oxidase/dehydrogenase (CKX), the key CK degradative enzyme, especially on the highest zinc rate (750 mg.kg-1 soil). On this rate, maximum endogenous CK concentrations in both control and stressed plants were found at the first and the last samplings, i.e. in the course of very young leaf development and just before or during flowering. The CKX activity of stressed plants exceeded that of controls during the whole development and reached the maxima at the last sampling of treated plants.
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Alternative Plant Utilization for Obtaining of Significant Nature Substances: Can Weed Find a Utilization?
Wimmer, Zdeněk ; Sajfrtová, Marie ; Sovová, Helena ; Pavlík, Milan ; Svobodová, Hana ; Jurček, Ondřej ; Wimmerová, Martina
Numbers of compounds and their mixtures, which are produced by plants, can be obtained by extracting plant materials by supercritical fluids. Phytosterols and phytoecdysterotds represent an important family of these plant products. They can be used in a synthesis of supramolecular structures with possible importance for targeted effect of drugs or other biological(y active compounds. Target organisms for the compounds investigated are: (a) insects - pests and human food competitors, also important as model system in investigation of convenient application forms of biologically active compounds; (b) cell cultures used during basic pharmacological research. Supramolecular structures may form convenient matrices for practical application of the biologically active compounds. It has already been proved that numbers of medicinal or cultural plants produce important natural compounds. The present question has appeared to be answered, if so far inutile weeds may be turned into important sources of pro-drugs for disease treatments.
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