Summary: Throughout the world there are many places with a high concentration of arsenic in water. In the Czech Republic is such a place the area of Mokrsko, where arsenic in groundwater reaches the values, which are well above recommended limits for drinking water. On the studied locality arsenic is bound to secondary minerals containing iron; however, in the reducing conditions of the fluvial sediments arsenic is bound to newly-formed realgar accumulations associated with organic matter. Aim of this diploma thesis was to characterize realgar from this locality and try to determine the way and conditions of its origin. For the purpose of research, realgar and pore- water have been sampled, using lysimeters and rhizon samplers. Specimen of realgar was characterized by numerous standard techniques (XRD, SEM, TEM, chemical and isotopic composition). Water samples have been analysed for As, F and S species. Analysis of realgar using XRD, SEM and TEM techniques confirmed the presence of nanocrystalline realgar, forming clusters and needle like aggregates. Domination of divalent iron and reduced form of As3+ (4,3-7,3 mg/L) in similar concentrations has been observed within the pore- water samples. The concentration of dissolved sulfide was very low (cca 30 µg/L), on the other hand, content of sulphate was always...

Nkana smelter belonged to the main sources of contamination by trace elements (especially Cu and Co) in the area of African city Kitwe (Copperbelt, Zambia). The main objective of this study was to compare elemental and isotopic composition of Zambian soils and tree rings, and to investigate biogeochemical processes between plants and soils in contaminated and uncontaminated environment. Elemental composition (Cu, Co, Cr, Mn, Fe, Zn, Pb, Cd, Hg and Tl) and isotopic composition of Cu (63 Cu/65 Cu) were determined in soils and tree rings of pine trees (Pinus latteri, Pinus kesiya) using ICP-MS , AMA and MC ICP-MS. Our results demonstrated that soils and tree rings were both affected by mining and metallurgical activity. Increasing content of elements with depth is the result of the mobility of the elements in uncontaminated soil profile. Soil from contaminated site had the highest metal contents especially in the upper part of the soil profile as a result of continuous contribution of metallurgical components during long-term smelter operation. Fractionations of Cu isotopes in soils were caused primarily by interactions with plants. Concentration changes that some elements showed in the individual tree rings could be the effect of variable intensity of pollution in the area. In the case of Cu, however,...

This thesis is dedicated to reasearch in radiolabeling bile pigment bilirubin. Minority bilirubin present in the body the form unconjugated. In this work, it was crucial synthesize radiolabeled bilirubin which could be monitored by detector in vitro experiments. A possible further applications, such bilirubin would be detectable in vivo experiments using µ-PET/SPECT (micro- positron emission tomography/single photon emission computed tomography) . The aim of this thesis propose variation for possible signs of bilirubin radioisotopes and synthesis of bilirubin derivates suitable for radioactive labeling. Another objektive of this work is the synthesis and study of the well-known derivative ranarubin called bilirubin, which could potentially have very simile characteristics, such as bilirubin and therefore would be a good candidate for radioisotope labeling and study of biological systems.

Human activities have largely impacted the environment and its biota to the extent that biodiversity declines can be seen worldwide. Biological invasions significantly contribute to these processes. Slovakia is a rapidly developing country stretching along the northern parts of the Pannonian basin and western Carpathian Mountains. Geological characteristics predetermine its extraordinarily high species richness thanks to largely preserved regions and habitats of high biological and conservational value. As a result, a strong population of the stone crayfish occurs in the western part of the country, while there is a countrywide distribution of the noble crayfish. On the contrary, the country's narrow-clawed crayfish is on the edge of extinction. The main reason behind the decline of this species is the expansion of the non-indigenous crayfish species transmitting the crayfish plague pathogen. Although sites of the stone and the noble crayfish occur in the upper parts of the river basins, there is a high risk of crayfish plague outbreaks, since the established spiny-cheek crayfish population are confirmed chronic carriers of the causative agent. Aquarist trade is increasingly recognized as an important pathway for the non-indigenous species introductions, out of which some may establish and become invasive. Freshwater crayfish, shrimp and crab species were recorded in the aquarist trade in Slovakia, counting altogether 26 different species. The marbled crayfish was one of the most frequently traded species. We identified several new sites of the marbled crayfish occurrence with established reproducing populations in very close vicinity of major rivers in the country. One of the newly identified flourishing spiny-cheek crayfish populations is located close behind a bank with a pumping station, i.e. critically close to a sidearm of the Danube River, with a confirmed crayfish plague infection. Marbled crayfish can become a crayfish plague carrier acquiring the pathogen from the infected spiny-cheek population in the Danube and rapidly spreading the disease along the river, thereby endangering the remaining populations of the narrow-clawed crayfish. More sites with the marbled crayfish are expected to occur in the country. Given their parthenogenetic reproduction, theoretically, a single individual is sufficient to establish a new sustaining population. Considering the high availability of the marbled crayfish in the pet trade industry and the rising numbers of established populations in the wild, research clarifying its potential impacts on the invaded ecosystems was warranted. We provide the first study investigating the trophic position and food preferences of the marbled crayfish in its well-established populations. Based on carbon 13C and nitrogen 15N stable isotopes analysis marbled crayfish were identified in the middle of the trophic chain with polyphagic diets. Marbled crayfish were found to utilize algae, allochthonous and autochthonous detritus, zoobenthos and macrophytes, thus being a strong competitor to a wide scale of organisms depended on the same food sources. The marbled crayfish transmit the energy from the bottom of the trophic pyramid to higher trophic levels as it was found to be a prey for top fish predators. This species can form dense populations and become a dominant component of the benthic fauna, thus affecting the entire invaded ecosystem. Its trophic niche width confirms high plasticity of the species, sustaining its populations in a wide range of different habitats. The marbled crayfish is thus a highly adaptable invader that can threaten not only the indigenous crayfish species by means of competition and the spread of crayfish plague, but also entire freshwater ecosystems and their biota.

Soil archives provide valuable information on the past of the environment, in particular vegetation history (Costantini 2018). The aim of this thesis is study the feasibility of using the modern method of near-infrared spectroscopy to study the vegetation history of chernozems, using previously collected databases (Vysloužilová et al. 2015) to extract information from new sites along the grassland-woodland boundary in Minnesota, USA. The results are then analyzed and compared to known information and the results of more traditional approaches.

Stable isotope composition of bulk leaf water is a useful proxy for geochemical and biological processes and is, thus, appreciated in ecological research and global modelling. The mechanisms determining the abundance of different isotopes in leaf water are not fully understood. The research presented in this thesis aimed to describe variability in leaf water isotopes which occurs under natural conditions and to distinguish which factors generate such variability. For that purpose, field sampling, water extraction, stable isotope analysis and measurements of several additional environmental and physiological characteristics were carried out at one sampling site during three subsequent growing seasons. The results obtained point out that oxygen isotopes rather then hydrogen isotopes have greater potential to be used in higher scale applications. Apart from that, several interesting ecophysiological interpretations of isotopic data have been made.

Coal is one of the major energy sources in the world and contains most of the elements from the periodic table. During combustion of coal these elements are released and redistributed. This may lead to environmental problems. Some of these elements are considered to be very dangerous for human and animal health and ecosystems. The knowledge of concentration and speciation of elements in coal is important for the prevention of the adverse environmental phenomena associated with the use of coal. One of the hazardous elements in coal is lead. The purpose of this work is to determine the concentration of lead and its isotopic composition simultaneously with determining the speciation of lead in coal. The ICP-MS method was used to determine the concentration and isotope ratios of lead. A total of 62 samples of subbituminous coal was analyzed. The method of selective extraction analysis BCR was used on 9 samples of subbitumnious coal to identify the speciation of lead in coal. Lead concentrations in coal were measured in the range of 0.25 to 78.84 mg·kg-1 . These concentrations correspond to the average concentrations of lead in most of the coals. Isotope ratio 206 Pb/207 Pb in coal samples ranged from 1.169 to 1.219. Isotopic 208 Pb/206 Pb ratio was measured in the interval 2.047 to 2.093. The isotopic...

The (Lomnice) LOM-1 borehole records a nutrient-rich quiet environment of the outer shelf to upper bathyal in the Mid Badenian (sensu Hohenegger et al. (2014)) of the Carpathian Foredeep. The LOM-1 borehole is rich of a fossil content with a relatively good preservation. The studied section can be correlated with the interval from 14.6 Ma (the FO of Orbulina spp.) to 13.42 Ma (the LO of Sphenolithus heteromorphus) which agrees with the beginning of the "Middle Miocene Climate Transition". The foraminifera for the carbon and oxygen stable isotope analysis were picked from the fraction 0.063-2 mm. The suitability for the stable isotope analysis was carefully evaluated based on the inner wall preservation. The isotopic analysis was done for fifteen samples with total 373 tests analyzed. Each analysis was performed from exactly one test. The following foraminiferal genera from different paleobiotops were used for the isotope analysis: Globigerina bulloides; Orbulina universa, Praeorbulina glomerosa; Globigerinoides spp.; Uvigerina spp.; Heterolepa dutemplei; Cibicidoides spp.; Gyroidinoides spp. and Melonis pompilioides to document the isotopic signal for the superficial and bottom waters. The oxygen and carbon isotope analysis from foraminiferal tests were used for the verification of the...

This biological study is focused on the possibility of using stable isotope analyses to determine the geographic origin of plants and mainly animals especially tortoises. In the experiment nineteen tortoises were divided into two groups which were fed by isotopically different food and water for one year. The samples of keratin from their shells were collected before and after the experiment. Then the samples were analysed for the ratio of particular isotopes using isotope ratio mass spectrometry.

This thesis deals with the isotopic composition of lead and 210 lead in recent galena from burning heaps after coal mining in the Lower Silesian basin. The studied sites were heaps in Radvanice, Markoušovice and Rybníček, where samples of galena, coal and burnt rocks were available. For the determination of the isotopic composition was used mass spectrometry with inductively coupled plasma (ICP - MS). Mass 210 Pb activity in galena was measured in a gamma - spectrometer Silar and the effect of radioactivity on galena crystal lattice was determined by the modified Williamson - Hall graph which was made from taken X-ray diffraction data. The values of isotope ratios in galena ranged for 207 Pb/206 Pb = 0,8402 to 0,8435 and for 208 Pb/206 Pb = 2,0663 to 2,0836. The average values of the coal were measured for 207 Pb/206 Pb = 0,8312 and 208 Pb/206 Pb = 2,0421. On the basis of these isotope ratios was found out that during the burning of coal and subsequent galena crystallization from hot gases there is no isotopic fractionation. Mass 210 Pb activity in galena ranged from 135 ± 9 Bq/g to 714 ± 22 Bq/g. Radioactivity of galena causes the developement of micro-deformation in the crystal structure. This micro-deformation is demonstrated by increased micro-strain in the crystal lattice. The level of this...