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Foundations in Volume Unstable Soils
Legut, Dana ; Weiglová, Kamila (referee) ; Hauser,, Jaroslav (referee) ; Zdražil, Karel (referee) ; Vašina,, Josef (referee) ; Paseka, Antonín (advisor)
This dissertation is concerned with the foundations in volume unstable soils and objects disorders which are related to this. The thesis was focused on the study of clay and loess soils which are abundant in the geological profile of the Czech Republic. First, the formation of the two groups of soils is introduced, then their properties are examined and finally the influence of vegetation on the former type and the influence of collapsibility in the latter type are investigated. The conclusion is, in fact, a recommendation on the design of structures so that the system of clay / structure is not damaged and that structures are not subject to renovations. Several instance of problems with structures are discussed which were subject to structural repairs employing both a civil and geotechnical engineers.
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Geochemical Study: Sediments as a Source and/or Trap of Mercury Contaminatin.
Májska, Milada ; Amouroux, David (referee) ; Zdeňka, Svobodová (referee) ; Dočekalová, Hana (advisor)
Rtuť je v přírodě přirozeně se vyskytujícím toxickým prvkem, jehož globální emise jsou ovlivňovány zejména antropogenními zdroji znečištění. Obrovský globální nárůst v usazování rtuti, zejména ve vodných ekosystémech, byl zaznamenán současně s počátkem průmyslové revoluce. Sedimenty jsou posledním místem úložiště nejrůznějších komplexů rtuti. Rtuť však zde může být přeměněna na toxičtější organickou formu, methylrtuť, pomocí transformačních procesů kontrolovaných různými fyzikálními, chemickými, ale i biologickými faktory. Navíc mohou být specie rtuti remobilizovány ze sedimentů pomocí difuze a resuspenzace a tak se sedimenty mohou stát i potenciálním zdrojem rtuti. Proces bioakumulace a bioobohacování tak pokračuje v potravním řetězci, ve kterém se člověk, i další zvířata, stává konzumentem methylrtuti. Stanovení celkové koncentrace rtuti není dostačující k porozumění osudu rtuti v přírodním prostředí a tak stanovení MeHg poskytuje nezbytnou doplňující informaci. Dostatečně citlivá a přesná analytická metoda pro stanovení specií rtuti je nezbytným nástrojem environmentální chemie. Metody vhodné pro stanovení specií rtuti v sedimentech jsou popsány v části metodologie disertační práce. Metoda stanovení methylrtuti v sedimentech pomocí automatické Headspace vybavené pastí („trap“) a spojené s plynovou chromatografií a fluorescenční detekcí je zde také popsána. Zvláštní pozornost je také věnována potřebám zásad čistého vzorkování, skladování vzorků a přípravě vzorků před samotou analýzou, jakož i samostatné části věnující se terénní studii rtuti a methylrtuti v sedimentech vytipovaných lokalit. Sedimenty jižní Moravy a severní Francie jsou srovnány z hlediska znečištění rtutí. Specie rtuti a další ukazatele (Fe, Mn, S) byly analyzovány v sedimentech, pórové vodě a povrchové vodě řek Dele a Lys (Francie) a Jihlava a Morava (Česká republika). Z hlediska posouzení vodních ekosystémů a jejich znečištění rtutí, je vhodné znát koncentraci rtuti v pórové vodě a posoudit dostupnost rtuti ze sedimentů. Technika difuzního gradientu v tenkém filmu je vhodným způsobem jak stanovit koncentraci rtuti v pórové vodě sedimentů. Do roku 2005 bylo použití této techniky pro měření rtuti značně limitováno. Ale nedávný pokrok především v dostupnosti možných sorpčních gelů vhodných pro stanovení rtuti umožnilo využití této techniky i pro stanovení rtuti. Byly použity různé sorpční gely: Spheron.Thiol, Duolite GT-73 a TiO2. Řeka Dele představuje past enormního množství antropogenní rtuti pocházející z průmyslových zdrojů a je považována za potenciální významný zdroj methylrtuti pro okolní prostředí a živé organismy především. Poslední část dizertační práce se zabývá aplikací dobře zavedeného experimentu využívajícím stabilní isotopy ke studiu metylačních a demethylačních procesů v sedimentech řeky Dele. Obohacené stabilní značkovače rtuti v anorganické formě (199Hg) and methylované formě (201MeHg) byly přidány do sedimentů. Tyto označené specie rtuti tak pomohly sledovat osud specií rtuti a vypočítat rozsah jejich přeměny v průběhu experimentu.
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Development of Gel Techniques for in situ Measurement of Bioavailable Metals in Soils and Sediments
Kovaříková, Vladěna ; Sommer, Lumír (referee) ; Janoš, Pavel (referee) ; Dočekalová, Hana (advisor)
The doctoral thesis deals with usage of gel techniques for in situ measurement of bioavailable metals in soils and sediments. The DGT technique was applied to soil samples from the localities of Zlín, Tuřany and Chrlice for estimation of bioavailable metals in soils. These soils were amended by sewage sludges in years 1980-1987. The experiment using diffusive gels with different pore size, APA and RG gels, has shown that the DGT can be used for assessment of trace metal soil complexes - small inorganic and larger organic. The results obtained by DGT measurements were approximately up to two orders of magnitude lower than metal concentrations obtained by leaching with sodium nitrate. The leaching with sodium nitrate does not provide true reflection of metal availability to plant root system and soil microorganisms and the DGT technique seems to be a better predictor of metal bioavailability. Only small differences between undisturbed and homogenized soil samples were found out by application of DGT to soil samples from localities of Veverská Bítýška and Ostrovačice. The undisturbed soil is not homogenous and the DGT unit gives information only about the part of the soil which is in direct contact with the unit. The procedure with soil slurry can be recommended for the characterization of large soil areas and estimation of bioavailable metals in soils. Gel techniques were also used for the study of processes occuring in sediments. Mercury species and other metals were analysed in surface water, pore water and sediments collected from two sampling sites in the Dele River in northern France. This river had been polluted during the last century by the activity of Métaleurop factory, which dealt with metal ore treatment. The application of DGT technique using two specific ion-exchange resins, Chelex-100 and Duolite GT-73, provided assessment of mercury in sediment pore water. DGT and DET techniques together with centrifugation provided also high resolution depth profiles of Fe, Mn, Zn, Pb, Cr and Cd in pore water. It is not possible to determine which sampling site was more contaminated. Only small differences in mercury species and metal content were observed between sampling sites. The Dele River can be classified as contaminated river according to total mercury content in sediments and as slightly contaminated river from the point of view of methylmercury content. Correlations between mercury species and sulphide content confirm that total mercury and sulphide content count among factors influencing the mercury release to pore water and controlling processes of methylation and demethylation. Only low toxicity of sediment slurries was found out by the bioluminiscence test with Vibrio fischeri. The results of doctoral thesis demonstrate gel techniques as a very good tool in environmental analysis.
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Hydrodynamic separation water flow sediment
Sajner, Pavel ; Neterda, Zdeněk (referee) ; Němec, Zdeněk (advisor)
The dissertation deals with clogging of reservoirs and ponds by redundant sediments which penetrate water system by erosion. It describes methods of extracting pond sediments. It contains measurement of dewatering of sediments on hydrocyclone and design of laboratory hydrocyclone and filter unit. In the conclusion there is design of technology of dewatering sediments which were extracted by wet method by drainage excavator. Numerical simulation of flowing in hydrocyclones is simulated in the CFX programme and dewatering technology is simulated in the CHEMCAD programme.
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Assessment the impact of the application of excavated sediments from the dam Luhačovice on the content of risk elements in arable soil
Kratěnová, Pavla ; Komendová, Renata (referee) ; Řezáčová, Veronika (advisor)
This diploma thesis focuses on an issue concerning an excavated sediment application on an arable soil and its impact on the soil quality based on a particular case of a deposition of the sediment from the dam Luhačovice on an adjacent agricultural area. The theoretical part of this thesis is focused on a soil and sediment characteristics and functions, contained risk elements, sampling methods, determination possibilities of particular risk elements and a description of conditions which emerged from a need for the deposition of sediment obtained during scavenging of the dam Luhačovice. In the experimental part was described the process of sampling, samples processing and determining of concentration values for chosen risk elements (Cd, Cu, Hg, Ni, Pb) using flame or electrothermal atomic absorption spectrometry methods. This part also contains an evaluation of obtained results and a validation of an approval for the sediment deposition.
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Sewage sludge and sediments evaluation via ecotoxicity tests
Ondrová, Jana ; Vávrová, Milada (referee) ; Zlámalová Gargošová, Helena (advisor)
Sediments and sewage sludges are part of the environment. Sewage sludges are formed in wastewater treatment plants as solid residues after water purification, therefore they have antropogenic origine. Although the sediment are formed by natural processes, humans also contribute to their formation. Sediments and sewage sludges can be a reservoir of a number of contaminants, due to their properties. Utilisation of sediments and sewage sludges as material for recultivation or a natural fertilizer is currently supported. But after application to the land, contaminants can be released to the environment. The consideration of ecotoxicological effects of sediments and sewage sludges is very important. Sediments and sewage sludges were ecotoxicologicaly evaluated by bioassays with water leacheate and by whole sediment bioassays. Daphnia magna, Thamnocephalus platyurus, Sinapis alba and Lemna minor were used to perform tests with water leacheate. Heterocypris incongruens, Lactuca sativa and Eisenia fetida were used to perform whole sediment tests.
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Monitoring of water and sediment contamination
Grajciariková, Eva ; Mravcová, Ludmila (referee) ; Vávrová, Milada (advisor)
The diploma thesis is focused on the issue of the presence of POPs in the surface water and sediments. Monitored compounds were chosen from the group of polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDE). Samples were collected in selected localities in the Slovak and the Czech Republic. Selected analytes were extracted with hexane from the aqueous matrix. Analytes were isolated by the ultrasonic extraction using a solvent mixture of hexane-dichlormethane from the solid matrix and the resulting extract was cleaned up by the column chromatography filled with the florisil and the silica gel. Target compounds were analysed by GC/ECD finally. Obtained results show the level of contamination in selected localities in the Slovak and the Czech Republic.
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Ecotoxicological evaluation of sediments
Dobešová, Zuzana ; Doležalová Weissmannová, Helena (referee) ; Zlámalová Gargošová, Helena (advisor)
Sediments of lotic and lentic water can be a reservoir of a number of contaminants, which can enter the aquatic ecosystem either due to the controlled discharge of waste water or leakage of various accidents or technological devices. Sediments can hereby affect not only the aquatic ecosystem, but also the terrestrial system in the case that they will be used as fertilizer or as a material for the recultivation. For this reason it is important to consider their potential ecotoxicity. Sediments were subjected to ecotoxicological bioassays and their potential ecotoxicity was assessed. The phytotoxicity assays on terrestrial plants Sinapis alba, Lactuca sativa and Allium cepa were used and the effects of aqueous extracts of sediments on the inhibition of growth their root were evaluated and the value of IC50 was determined. For the ecotoxicological assessment of sediments and determination of IC50 value also Lemna minor as a representative of aquatic plants was selected. For more objective assessment of the sediment ecotoxicity aquatic invertebrates as Artemia salina and Daphnia magna were selected and the value of LC50 or EC50 was determined.
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Determination of mercury alkylderivatives in water ecosystem
Doležalová, Jana ; Vávrová, Milada (referee) ; Čáslavský, Josef (advisor)
Diploma thesis is oriented on the question of the fate and occurence of mercury and its derivatives in water ecosystems. At first, deep literature review will be worked out. At second, the optimal analytical procedure for the determination of mercury alkylderivatives in water ecosystem compartments will be proposed and verified. At third, real samples from selected water ecosystems will be taken and analyzed.
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Sulfonamide residues in sediment and sludge from wastewater treatment plants
Chaloupková, Petra ; Lacina, Petr (referee) ; Vávrová, Milada (advisor)
The aim of the bachelor’s thesis was a method optimalization for extraction of sulfonamides from sediment and sewage sludge samples from wastewater treatment plants. This optimized method was used for analyzing sulfonamides in real soil and sewage sludge samples. Antibiotics are commonly used as a prevention and medicament for human and animals. Drugs and their residues enter to wastewater treatment plants within excrements and then they can be a part of sewage sludge or they can occur in treated water. It can also enter environment as a part of soils or sediments. Three extraction methods were chosen for optimizing; a pressurized solvent extraction, a microwave-assisted extraction and an ultrasonic extraction. Extracts were cleaned by solid phase extraction and analysed by liquid chromatography with diode array detector.
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