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Environmental contamination of mining areas and the possibilities of their phytoremediation
Pecina, Václav ; Pospíšilová, Ľubica (referee) ; Pavlů,, Lenka (referee) ; Komendová, Renata (advisor)
Environmental pollution with heavy metals is a global problem escalating in areas with mining. The search for solutions to this problem has been the subject of research for the past decades. This work is conceived as a set of four case studies focused on environmental pollution of mining areas and phytoremediation of polluted soils. The conclusions of all four studies are discussed in the context of the situation in Mongolia, where the investigation of this issue is at an initial stage. The results of the environmental pollution investigation in the mining areas showed (I) the unsuitability of the transformation of the mining-processing plant and the adjacent heap in Příbram into a forest park due to the persistent heavy pollution of the soil with the heavy metals (As, Cd, Pb and Zn) causing potential health risks for visitors and inhibition of the tree seedlings even after the implementation of the reclamation project and (II) the low level of soil pollution of the mining areas in Mongolia with no expected risks to the local population. The results of the phytoremediation studies confirmed the potential of Lupinus luteus L. and Festuca rubra L. in combination with specific additives (mainly biochar from willow chips, poultry feather ash and chalcedonite, respectively) for aided phytostabilization of soils polluted with Cd, Cr, Cu, Ni and Zn, and Cr(VI), respectively, and thus the potential for use in phytoremediation of heavy metal-polluted soils in mining areas. Regarding uncontrolled grazing in Mongolia, phytostabilization of heaps and making them inaccessible is necessary to reduce the risks of spreading contamination and intoxication not only of livestock. A promising species for phytoremediation in Mongolia may be Larix sibirica Ledeb.; a suitable type of mining waste management aided phytostabilization focusing on the use of potentially available manure and wood chips. Future research should implement experiments with identified plant species and additives and find other suitable local species capable of creating a continuous vegetation cover.
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Chemical and Physical Transformations of Humic Acids
Vlčková, Zoja ; Pospíšilová, Ľubica (referee) ; Janoš,, Pavel (referee) ; Pekař, Miloslav (advisor)
Tato práce představuje pilotní studii testující souvislosti mezi biologickými vlastnostmi a strukturou huminových kyselin extrahovaných z původního a modifikovaného jihomoravského lignitu, důl Mír, Mikulčice. V první části práce byly testovány metody vhodné ke zvýšení výtěžku huminových kyselin extrahovaných z lignitu. Oxidace lignitu v plynné fázi nepřinesla uspokojivé zvýšení výtěžku a byla instrumentálně poměrně náročná. Dále proto byla zkoumána jen oxidace v kapalné fázi a modifikace nízkomolekulárními organickými kyselinami. Modifikace organickými kyselinami byla inspirována procesy podporujícími biologické funkce v rizosféře, t.j. kořenový systém vylučuje exudáty způsobující změny v supramolekulové struktuře okolní organické hmoty čímž zlepšuje její mobilitu a prostupnost buněčnými stěnami. Primární struktura huminových kyselin připravených v této práci byla zkoumána prostřednictvím elementární analýzy a spektrálních metod (13C CPMAS NMR, EPR a UV-VIS spektroskopie). Navzdory tomu, že primární struktura vykazovala jen malé rozdíly, měření biologické aktivity a genotoxického potenciálu prokázalo, že huminové kyseliny a jejich humáty získané z lignitu s rozdílnou předúpravou vykazují odlišnou bioaktivitu. Proto byla dále zkoumána supramolekulární struktura vzorků ve zředěných roztocích, a to prostřednictvím vysokoúčinné vylučovací chromatografie, měření ultrazvukové rychlosti a hustoty. Testovány byly dva různé protionty – draselný a amonný. Získané výsledky potvrdily předpoklad, že pozorované změny v kvalitě humátů jsou závislé na protiiontu, koncentraci humátu v roztoku a také na metodě předúpravy původního lignitu. Obě zvolené metody předúpravy lignitu prokázaly svůj potenciál produkovat huminové kyseliny s rozmanitými biologickými vlastnostmi, aplikovatelné v zemědělství, životním prostředí a potenciálně i ve farmakologii.
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Chemical and thermal stability of humic complexes
Nováková, Tereza ; Pospíšilová, Ľubica (referee) ; Klučáková, Martina (advisor)
The aim of this diploma thesis was the study of relation between chemical and thermal stability of complexes of humic acids with heavy metals, namely nickel, cobalt and copper. Complexes were prepared with metal solutions of three different initial concentrations. Through UV-VIS spectrophotometry were determined adsorbed amounts of incorporated metal ions in the structure of humic acid; it was affirmed that amount of bounded metal ions increases with increasing initial concentration. Chemical stability was determined as an amount of released metal ions, two of extraction agents were used (solution of MgCl2 and HCl), total bounded amount was distribute into three different fractions; residual fraction, strongly bound fraction and mobile and ion-exchangeable fraction. Changes that occured in the structure of humic acids after complexation and extraction were investigated by FT-IR spectrometry. Thermo-oxidative stability was tested through thermogravimetric analysis (TGA) and differential scanning calorimetry. The results of this diploma thesis has showed comparision of complexes of two different humic acids. They have confirmed an impact of each metal ion on thermo-oxidative stability of humic acids. The relation between chemical and thermal stability was compared through correlation of data obtained by these methods.
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Utilization of chronopotentiometric titration in humic research
Viktorinová, Jana ; Pospíšilová, Ľubica (referee) ; Klučáková, Martina (advisor)
Humic acids are natural substances belonging to the group of humic substances. They arise mainly decomposition of plant residues. They are contained in soils, peat, sediments, young coal, water and even in the air. Humic acids are only partially soluble in water with increasing pH increases their solubility. Diploma thesis focuses on the use of chronopotentiometric titration of humic research. This method is mainly used for the determination of trace concentrations of analytes. This work is focused on the determination of acidity by potentiometric titration and the determination of dissociation constants using chronopotentiometry with measurement of pH of prepared samples.
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Calorimetric study of interactions of humic substances with metal ions
Solná, Irena ; Pospíšilová, Ľubica (referee) ; Klučáková, Martina (advisor)
The main object of the diploma thesis is study of interaction beetween humic acids and selected metal ions using calorimetric titration. The research about reactivity of humic substances is done comparing the different models used to describe the variety of properties of humic substances. In experimental part the methods of FT-IR spektrometry, potenciometric and conductometric titration are used to recieve the total acidity and carboxylic acidity of lignite humic acid. The optimalization of isothermic titration calorimetry is done to be used within study of reactivity of humic acids, revealing the best correlation with sols of studied humic acid. The basic organic compounds were used including benzoic acid, ftalic acid, salycilic acid, pyrocatechol and phenol as models of bonding groups in humic acids. The reaction enthalpy was calculated from the titration of models and results were compared with semiempiric quantum chemistry calculations following INDO method.
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Conformation and molecular organization of humic acids in aqueous solutions
Věžníková, Kateřina ; Pospíšilová, Ľubica (referee) ; Klučáková, Martina (advisor)
This diploma thesis deals with the conformation and molecular organization of humic acids in aqueous solutions. Humic substances have heterogeneous and polydisperse nature, therefore their secondary chemical structure has not yet been defined properly, neither has their conformational arrangement. The conformation of humic substances in the solutions is mainly stabilized by weak disperse forces, such as Van der Waals, -, CH- interactions and hydrogen bonds. Humic substances in the solutions tend to form aggregates that are held together mostly by the intermolecular hydrophobic interactions. Concentration series of humic acids were prepared in three different mediums of constant ionic strength: NaOH and NaCl (prepared either by neutralization NaOH by HCl or direct dilution by solution of NaCl). Several analytical methods have been used to determine conformation and molecular organization of humic acids: potentiometric determination of pH, direct conductometry, ultraviolet and visible spectroscopy, density measurement, dynamic light scattering, laser Doppler velocimetry and high resolution ultrasound spectrometry. It was confirmed that the conformation and molecular organization of humic acids in aqueous solutions depend not only on pH of medium, but they also depend on chemical nature and concentration with the same pH. Results showed that hydrodynamic diameter of particles is significantly increasing in NaCl medium prepared by neutralization NaOH by HCl, particularly at low concentrations, which corresponds to higher values of zeta potential obtained. Concentration dependencies of ultrasonic velocity and compressibility also indicate the changes in conformation and molecular organization corresponding with results from other methods used.
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Influence of soil management on properties of humic substances
Rubínková, Eva ; Pospíšilová, Ľubica (referee) ; Klučáková, Martina (advisor)
The aim of the Diploma thesis is to consider an influence of soil management (rotation of crops on arable land and grassland) to quantity and quality of humic substances. These properties are depended not only upon way of soil management, but also upon climatic effects, such are rainfall, temperature, elevation above sea-level, level of underground water and content of clay. Significantly influenced factors are content and form of organic carbon which is very tightly bonded to humic substances. In this work the humic acids content and properties progression was studied in given time period. Also the effect of crop rotations to changes of physical and chemical properties of humic acids in soil environment was observed. Diploma thesis was realized in co-operation with Mendel University in Brno, which supplied elaborating samples. Studied soil samples were taken from humus horizon Cambisol modal Vatín during years 1999–2006, always in autumn. Individual samples were characterized by available analytical methods, which are generally used in humic substances research area. They are especially fluorescence spectrometry, UV-VIS and infrared spectrometry and acid-base and conductometric titrations.
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Influence of compost application on properties of soil humic substances
Enev, Vojtěch ; Pospíšilová, Ľubica (referee) ; Klučáková, Martina (advisor)
The aim of this diploma thesis is to study to the influence of compost addition to soil humic substances extracted from blackland luvicsol. Humic substances extracted from soil and from compost were characterized by titration with potentiometrical and conductival indication, UV-VIS, FT-IR and 3D EEM fluorescential spectroscopy. Compost in amount of 124, 239 and 478 t/ha was applicated and manured into dept of 150 mm at blackland luvicsol. The main aim of thesis was the appraisal of compost influence into fluorescent attributes of soil HS and localization of fluorescent peaks at excitation emission spectrums. Next part of diploma thesis was focused on the study of spectroscopic attributes of soil HS and compost by UV-VIS and infrared spectroscopy with Fourier transformation. Humic substances were characterized by humifical index E4/E6 and transmissional vibratile spectrums. The last aim of diploma thesis were the characterization of soil HS extracts and compost by acidimetral titration. For each sample was calculated value of H+ ionts amount of substance from measured titrational curves.
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Fluorescence of soil and lignite humic substances
Konečná, Soňa ; Pospíšilová, Ľubica (referee) ; Fasurová, Naděžda (advisor)
The purpose the diploma thesis was to determine main fluorophores of soil and lignite humic substances using methods of 2D synchronous fluorescence spectroscopy (SFS) and 3D SFS. These fluorescence methods are frequently used for characterization multifluorophore systems. Measured synchronous spectra were compared with standards IHSS. Next to that the aim was to find differences between chosen samples of humic and fulvic acids.
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