|
|
The Introduction of Contact Ecotoxicity Tests for the Assessment of Terrestrial Ecosystems
Modlitbová, Pavlína ; Kráčmar, Stanislav (referee) ; Beklová, Miroslava (referee) ; Demnerová, Kateřina (referee) ; Vávrová, Milada (advisor)
This dissertation thesis is focus on using toxicity tests with testing organism - terrestrial isopod Porcellio scaber. This organism is use for toxicity assessment of selected anorganic compunds which could contaminate terrestrial ecosystem. This organism was selected for several reasons - sophisticated test methodology; well known biology of these animals and their ecological relevance. Besides classical endpoints such as mortality, change in mass of test specimens and the effect of the presence and concentration of contaminants onto food consumption; we monitored changes in the morphometric characteristics at the level of tissues and cells, the cytotoxicity and possibly bioaccumulation in various parts of the body of the organism. Selected test substance in this thesis were nanoparticles and inorganic salts. Wherein for chosen gold nanoparticles was carried out a complete study presents several levels of organization of living matter (organism, tissue, cell). For selected salts compound, this study was carried out on the behavior of organisms and classical endpoints.
|
|
|
Production of organic acids by fibrous microscopic fungi and utilization of their biomass for removal of risk elements
Juglová, Zuzana ; Hudečková, Helena (referee) ; Urík,, Martin (advisor)
The aim of this bachelor thesis was to determine the most advantageous method for production of organic acids by microscopic flamentous fungus Aspergillus niger and to evaluate mercury bioaccumulation efficiency on collected fungal biomass. The theoretical part focuses primarily on utilization, metabolism and production on individual organic acids. This is followed by section focused on the toxicity of mercury and the principles of bioaccumulation of heavy metals in biomass. The experimental part focuses mainly on the optimization of cultivation, determination of content of produced organic acids, depending on the type of cultivation. Second point of practicle part is evaluating of mercury bioaccumulation depending on the initial concentration of mercury in solution. In overall comparison, the best type of cultivation is dynamic. Higher biomass yeild resulted in higher production of organic acids. The higher biomass synthesis is also beneficial for bioaccumulation of mercury.
|
|
|
Speciace rtuti v rybích tkáních
Hrůzová, Marie
The diploma thesis is focused on the issue of contamination of freshwater fish species by chemical forms (species) of mercury. To monitor mercury speciation in fish tissues, four locations in the Czech Republic were selected - the Záskalská reservoir, Rybníkářství Pohořelice a.s., the Smrk pond, and the Lipolec pond. The Záskalská reservoir is located near the historic cinnabar mine, hence an increased risk of fish contamination was expected. No significant source of mercury contamination was identified in the other aquatic ecosystems. Four fish species - perch (Perca fluviatilis), roach (Rutilus rutilus), pike (Esox lucius), and European eel (Anguilla anguilla) were caught for analysis. Fish tissue samples (muscles, gills, liver, and skin) were analyzed for total mercury concentrations using atomic absorption spectrometry on an AMA 254 and for individual mercury species using High-performance liquid chromatography with atomic fluorescence detection (HPLC-CV-AFS). The highest total mercury contents were found in the muscles of fish from the contaminated Záskalská reservoir. The muscle tissues of pike, perch, and roach from the Záskalská reservoir exceeded the limit set by Regulation No. 1881/2006 EC. Only inorganic mercury species (Hg2+) and methylmercury species (MeHg+) were found in fish tissues. The highest amounts of methylmercury were found in muscle tissues (63-96 %), followed by skin (55-90 %), liver (31- 82 %), and gills (42-81 %). Statistically significant differences in mercury species content were compared between predatory and non-predatory fish, contaminated and non-contaminated locations, and the thesis also assessed the impact of age, species, and diet on the speciation of mercury in fish tissues.
|
|
|
LIBS analysis of heavy metals in plant matrice
Opluštil, Marek ; Pořízka, Pavel (referee) ; Krčma, František (advisor)
This bachelor thesis deals with the analysis of cadmium distribution in the plant matrix using laser - induced breakdown spectroscopy (LIBS). Technical hemp plants grown in soil with different cadmium concentrations were used as samples. The theoretical part focuses on LIBS methods in terms of basic principles, description of accompanying phenomena during measurements and instrumentation. Advantages and disadvantages over other analytical techniques as well as practical applications are also described. In addition, the issue of cadmium in the environment, its occurrence and use in human activities is described. In the experimental part, the methodology for sample preparation for LIBS and ICP-OES analysis is described. The aim of this work is to observe the effect of cadmium on the growth of plants that were successively harvested weekly until the fourth week. Subsequently, plant and soil samples were prepared for LIBS and ICP-OES measurements and the results were evaluated. ICP-OES analysis led to the determination of each element content. The LIBS method provided information on the areal distribution of the elements (spectral maps), allowing to see in which plants part the determined element is located. It is clear from the results of the experimental part that the LIBS method is very advantageous and efficient in the analysis of elements in biological matrices, both biogenic and toxic.
|
|
|
Bioakumulace vzácných kovů z červeného kalu
NÁHLÍK, Vít
This study deals with the bioaccumulation of scarce metals, especially lanthanides, contained in red mud. The effect of red mud is studied on cultures of La4 mutant of the green alga Desmodesmus quadricauda and on red microalga Galdieria sulphuraria under different metabolic regimes with the addition of acidic extract of red mud.
|
|
|
Detection of heavy metals in hard tissues by laser-induced breakdown spectroscopy
Konečná, Anna ; Novotný, Karel (referee) ; Pořízka, Pavel (advisor)
This master thesis deals with the detection of heavy metals bioaccumulated in hard tissues by laser-induced breakdown spectroscopy (LIBS). As model samples, murine mandibles and femurs of animals exposed to lead oxide or cadmium oxide nanoparticles were used. The exposure of animals lasted for 6 or 7 weeks. Control group of animals was exposed only to air for a reference. The distribution of biogenic elements and contaminants was determined by mapping the samples' surface using LIBS with a spatial resolution of 30 and 100 µm. The second part of the work focused on the possibility of using the method LIBS for quantitative analysis. Samples of hydroxyapatite standards were prepared as reference material. By their analysis a calibration curve was constructed, and the limits of detection and quantification were determined. Furthermore, a model for prediction of heavy metal concentration by calculation from the calibration curve was presented.
|
|
|
Bioaccumulation of heavy metals in macroinvertebrates: relationship between concentrations and organism size
Hanzlíková, Lenka ; Dočkalová, Kateřina (advisor) ; Hořická, Zuzana (referee)
The size of benthic organisms is one of many possible factors affecting resultant concentrations of metals accumulated in organisms from surrounding water environment. Partial information is presented in research publications which state this dependency with different conclusions. So far the dependence was not unequivocally interpreted. Relationship between concentration and body size may differ among various metals and also between individual species of macroinvertebrates. This bachelor thesis is a research of professional literature and its result is analysis of existing knowledge of types of this dependancy and comparison of individual representatives of aquatic invertebrates and individual metals. Significance of the trend of dependence as a factor having the influence on the final interpretation of data on the concentrations of monitored substances, especially heavy metals is to be assessed. Result of this work should facilitate the interpretation of data for future analysis of heavymetals in aquatic invertebrate organisms. Keywords: bioaccumulation, heavy metals, macroinvertebrates
|
|
|
The study of vertical mobility of heavy metals and their transfer to mushrooms
Jurnečka, Roman ; Doležalová Weissmannová, Helena (referee) ; Komendová, Renata (advisor)
This bachelor thesis deals with the issue of contamination of forest soils and edible mushrooms with lead, cadmium, copper and zinc in the Jeseníky Mountains, specifically in the Domašov and Vápenná forests. Sampling took place at 12 localities, divided into spruce and beech stands. Atomic absorption spectrometry AAS ContrAA 800D was chosen to determine the content of selected heavy metals. Based on the measured values of the concentrations of the studied metals and other soil properties, dependences were created to determine the vertical mobility of selected metals in the soil profile. Vertical mobility depends on the physico-chemical properties of the soil (pH, C and S content). The dependence of the content of selected heavy metals in the soil on the pH value of the soil was found. In the case of lead, the sorption capacity of the soil organic component was confirmed. The risk and above-limit content of Pb, Cd and Cu was found on the yellow-boletus mushroom. Cadmium shows the highest bioavailability. Lead was evaluated as the element with the lowest mobility.
|
|
|
Detection of luminescent nanoparticles in plants by laser spectroscopy
Střítežská, Sára ; Novotný,, Karel (referee) ; Modlitbová, Pavlína (advisor)
This diploma thesis deals with evaluation of toxicity and bioaccumulation of photon-upconversion nanoparticles (UCNPs) in model plant maize (Zea mays). Lanthanide-doped UCNPs with different composition and size were tested in three different concentrations in this work. The exposure took place for 168 hours. Toxicity was assessed based on four macroscopic toxicological endpoints (mortality, the length of belowground part of the plants, the length of aboveground part of the plants and whole plants length). Spatial distribution of elements yttrium, ytterbium, erbium and gadolinium in model plants was determined using laser induced breakdown spectroscopy with spatial resolution of 100 m and 26 m. Distribution of UCNPs in plants was further studied with photon-upconversion microscanning with spatial resolution of 40 m. Stability of UCNPs during and after the plant exposure was also discussed in this thesis.
|
|
|
The study of contamination of forested areas of the Czech Republic by mercury
Trávníčková, Gabriela ; Řezáčová, Veronika (referee) ; Komendová, Renata (advisor)
This bachelor thesis deals with the issue of mercury in the environment. It focuses on determining the concentration of total mercury in edible mushrooms and in the soil in 12 localities in the Jeseníky Mountains. A single-purpose absorption spectrometer AMA 254 was used to determine the mercury content. The sites where sampling took place were divided into 6 sites with spruce stand and 6 sites with beech stand. No relationship was found between the type of stand and the amount of accumulated mercury in the mushrooms. On a representative sample of yellow-boletus mushrooms found in each locality, it was found that the higher the amount of mercury in the mushroom, the lower the amount of mercury in the soil. The fungi are therefore able to accumulate mercury from the environment. Thus, they can become a potential source of intoxication when ingested. The mobility of heavy metals in the soils depends on many soil properties (pH, carbon and sulfur content). Metals form more soluble compounds in lower pH environments. The soil pH was very low and the lower the soil pH, the higher mercury concentration in the soil. This fact could be supported by acid fallout. The relationship between the mercury content and the carbon content of the soil confirmed that carbon has the ability to bind mercury. The higher the amount of carbon in the soil, the higher the amount of mercury.
|
guest ::
