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The content of selected group 1 and 2 metals in edible mushrooms
MÁCHOVÁ, Nikola
Edible mushrooms are able to accumulate elements, especially some heavy metals and radionuclides, in their fruiting body. This work engages in accumulation of chosen metals (Groups 1 and 2) in basidiomycete fungi and soil. The first picking happened in autumn 2017. Eleven mushroom specimens were found - several fruiting bodies of each type. The soil where the mushrooms had grown was also taken. During the other picking in autumn 2018 ten types of mushrooms were taken. The locality in the Czech Republic (Ledenice) was chosen, because these fungi were frequently found there: Agaricus campestris, Boletus edulis, Suillus variegatus, Xerocomellus chrysenteron, Neoboletus luridiformis, Leccinum rufum, Macrolepiota procera, Suillus luteus, Imleria badia, Leccinum scabrum, Lactarius deliciosus, Agaricus silvaticus, Suillus bovinus and Amanita rubescens. The chosen metals were Lithium (Li), Strontium (Sr), Cesium (Cs) and Rubidium (Rb). I used methods of atomic absorption spectrometry (AAS). In both analysis (2017 and 2018) the largest content of Lithium was recorded in Agaricus campestris fruiting body (2.3 mg/kg and 1.6 mg/kg) and the largest content of Strontium in Leccinum rufum (3.7 mg/kg and 6.6 mg/kg). It was shown that varieties of the Bolete family demonstrated the biggest accumulation of Rubidium (Boletus edulis 519 mg/kg, Neoboletus luridiformis 398.6 mg/kg). The biggest content of Cesium (about 1.1 mg/kg) was recorded also in this family.
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Involvement of AtKT/HAK/KUP high-affinity transporters in plant K+ and Cs+ uptake
Šustr, Marek ; Tylová, Edita (advisor) ; Maršík, Petr (referee)
Potassium is essential macroelement and large amount of potassium is taken up by plants, because it's the major osmotic of plant cell. Due to various potassium availability in different kinds of soil, plants have evolved transport system that can maintain sufficient K+ uptake between several orders of magnitude of potassium concentration. In Arabidopsis thaliana mechanism of K+ acquisition is well understood and it's known that AtHAK5 is mainly involved in K+ uptake in its very low concentrations. AtHAK5 belongs to KT/HAK/KUP family that consist 13 members in A. thaliana. There's known function for some members for example in auxin transport in root tip (TRH1) or in K+ efflux in stomatal closure (KUP6). In this thesis possible involvement of yet unstudied transporters KUP5, KUP7, KUP9 and KUP10 in K+ acquisition and homeostasis in A. thaliana was investigated. In vitro cultivation showed that kup9 mutant has very short lateral roots in K+ deficiency. On the other hand kup5 mutant showed significantly higher dry weight in K+ deficiency than Col-0. Kup9 phenotype was successfully replicated in subsequent cultivations and anatomy of lateral root apical meristems was investigated. Root tips of kup9 were differently organized in K+ deficiency and they showed signs of early termination of meristems. To...
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Uptake and metabolism of 137Cs in plants
Šustr, Marek ; Tylová, Edita (advisor) ; Maršík, Petr (referee)
Plants are able to uptake radiocesium from soil, which is the potential route to enter the food chain. Cesium mobility in soil is determined by clay particles. Cesium can be reversibly ad- sorbed on their surface or can be fixed between layers. Mineral illit has the highest selectivity for cesium due to its frayed edges. Organic matter determines cesium mobility only in soil with organic matter content above 90 %. Cesium is more available for plants in this soil. Cesium uptake varies among species. Many plant species accumulating big amounts of cesium belong to family Chenopodiaceae. Cesium uptake is affected by other cations in soil solution. Potassium is the most effective one. Increasing of external potassium concentration from 50 μM to 250 μM decreased cesium uptake thirty-fold. Potassium affects cesium mobili- ty in soil and plant uptake. Due to chemical similarities of cesium and potassium some potassium transporters efficiently transport both cations. Potassium transporters are therefore considered the main entrance site in plant roots. Great contribution to cesium uptake is dedi- cated to high-affinity potassium transporter HAK5. Another great part of cesium uptake is mediated by non-selective cation channels. Plants can uptake up to 80 % of cesium applied on shoot surface. Cesium is highly...
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Effect of potassium on stable cesium uptake by Calla palustris from aqueous solution
Petrůvová, Nicola ; Komínková, Dana (advisor) ; Petr, Petr (referee)
The aim of the thesis was to evaluate the effect of potassium on receiving of stable cesium and evaluate the appropriateness of Marsh Calla (Calla palustris) for phytoremediation. The experiment was conducted in a green-house environment where the plants were grown in an aqueous solution. The plants were exposed then to a stable isotope of cesium (133Cs) at a concentration of 1 mM CsCl. Potassium was added to the plants in the form of potassium sulphate (K2SO4), in five different concentrations (0.5 mM, 1 mM, 2 mM, 5 mM and 10 mM). Plants were exposed for 8 days. The largest average income of cesium (9,37 %) had a plant without added potassium. The root part of the plants showed a greater cesium content than the ground part. Based on the total intake of cesium from an aqueous solution, calla marsh can be estimated as a plant usable for phytoremediation.
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Impact of nitrogen on accumulation of Cs by Calla palustris
Benediktová, Eva ; Komínková, Dana (advisor) ; Petr, Petr (referee)
This work deals with the evaluation of Calla palustris utilization for phytoremediation and clarifying how nitrogen influences the uptake of cesium from aqueous solution. The plants were subjected to nitrogen exposure, which consisted of five different concentrations of NH4+ and NO3- and 0.5 mM CsCl, for eight days. The greatest amount of cesium (13.5%) accumulated the plants without the addition of nitrogen, the smallest amount accumulated plants with concentrations of 6: 3 (3.9%), 8: 4 (3.6%) and 10: 5 NH4NO3: NH4Cl (3.5%). Calla has proved to be suitable for phytoremediation, however with the need for longer exposure. Besides these main hypotheses it has been moreover shown that the state of plants affected the uptake of cesium and that nitrogen influenced the condition of the plant. Further it has not been observed noticeable difference in uptake of cesium in roots and stems with leaves.
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Impact of potassium on accumulation of Cs by Calla palustris
Poláková, Monika ; Komínková, Dana (advisor) ; Petr, Petr (referee)
Environmental contamination with radionuclides is a growing problem in the world. Phytoremediation seems to be a suitable method for the removal of radionuclides from the environment. The aim of this study was to determine the impact of potassium on accumulation of stable isotope 133Cs and evaluate the suitability of plant species Calla palustris for phytoremediation. Plants were grown in a water solution in a greenhouse and after one week of pre-cultivation were exposed to stable isotope 133Cs (0,5 mM CsCl). Potassium was added in five various concentrations in the form of K2SO4. The level of cesium in plants was measured after 8 days of exposition. Plants without added potassium absorbed the most cesium (11,52 %). Plants with the highest concentration of added K2SO4 10 mM (3,45 %), 5 mM (3,62 %), 2 mM (5,57 %) absorbed the least. Higher 133Cs accumulation was measured in the plant roots than in the above- ground plant parts. Total uptake of cesium by Calla palustris suggests the possibility to use Calla palustris for phytoremediation.
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Knowledge of population in a selected region about the Chernobyl Nuclear Power Plant accident consequences
PRAŽÁK, Marek
The Chernobyl nuclear disaster of April 26, 1986 is the worst nuclear accident in the history of mankind. An experiment conducted in the 4th reactor resulted in its explosion and a huge amount of radionuclides escaped into the environment in the course of the subsequent fire. The greater part of Europe was contaminated by radioactive fallout, including the former Czechoslovak Socialist Republic. From a health point of view, the most harmful radioactive substances causing radioactive contamination were caesium 137Cs and iodine 131I. The then government did not provide objective and true information to the citizens and the media depicted the disaster as an insignificant incident. I set the following goals of my thesis: a) to develop an overview of immediate and especially long-term consequences of the accident; b) to analyse the knowledge of the population of the South Bohemian Region of the consequences of the Chernobyl disaster depending on the age of respondents. For fulfilling the set goals, I set myself the following hypotheses: H1) the theoretical division of the population's knowledge will be normal; H2) the knowledge of persons over 45 years of age will statistically be significantly higher than that of younger people. I handled the given theme using available specialized literature, Internet sources and publications published by relevant institutions. In the introductory part I describe the construction of the power plant, basic technical parameters of the reactor used and the course and causes of the actual accident. The next section is focused on the consequences of the accident in individual time periods immediately, after 10 years and after 20 years. I devote myself both to influences on human lives and health and to environmental, social, economic and psychological consequences. Furthermore,I describe the situation in former Czechoslovakia and the way of informing the population by the then government. The last section of the theoretical part is dedicated to the present situation in the Chernobyl region and at the power plant itself. While compiling the research part of the thesis, I gathered data among the inhabitants of the South Bohemian Region through questionnaire investigation. I addressed a total of 280 respondents, of which 140 were under 45 years of age and 140 were over 45 years of age. The questionnaire contained 15 questions concerning basic, not professional knowledge in this area. For the purposes of my questionnaire investigation, I divided the South Bohemian Region into districts. The selection of individual towns within the framework of the questionnaire investigation was carried out at random, by drawing lots. 280 questionnaires were completed in all, of which 140 questionnaires were completed by respondents under 45 and 140 questionnaires were completed by respondents over 45. By drawing lots, I selected 100 questionnaires out of these completed questionnaires, each age group being included. The test of the set hypotheses and statistical evaluation are carried out using descriptive and mathematical statistics. I carried out statistical evaluation by testing normality, using X2-good agreement test. I mutually compared the knowledge of the groups monitored by testing using a two-sample t-test, based on the estimate of empirical parameters from each group. Based on statistical investigation I came to the conclusion that the division of the population's theoretical knowledge was normal, which confirms the first hypothesis. The results of the investigation also unambiguously confirmed the fact that the knowledge of the population over 45 years of age was statistically significantly higher than the knowledge of the younger group of respondents. As far as total evaluation is concerned, the average value of correct answers in case of the older group of respondents reached 71%, while the younger group showed just 44% of correct answers, which confirms the second se hypothesis.
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Agroekologické důsledky havárie reaktorů v japonské jaderné elektrárně Fukušima I. se zaměřením na vodní ekosystémy
Krejčí, Michal
This thesis deals with agroecological consequences of the Fukushima Daiichi power plant accident and it focuses on aquatic environment. It includes short history of radioactive elements in energetics. It also includes properties of the most important fission products. The thesis describes the accident of the power plant, fission products that were released into the environment through atmospheric release and direct discharges of contaminated water, measuring and monitoring of the contaminants, their movement and accumulation in river and marine ecosystems. The thesis focuses on radioisotope 137Cs, its accumulation in river and ocean sediments, sea algae and aquatic organisms. There is a special chapter about accumulation of 137Cs in fish which are a key component in aquatic ecosystems and also they are often consumed in Japan.
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Content of cesium-137 in forest ecosystem in selected locations
SEBEROVÁ, Pavlína
The human and the whole environment are irradiated from the different sources (natural or artificial). The natural sources of radiation are cosmic and sun rays or the natural radiation of the Earth. The artificial sources mean cyclotrons, X-rays, particle accelerators, nuclear reactors and others. Natural cesium is located very rarely on Earth, but it has many artificial isotopes (for example Cs-137 and Cs-134). The Cs-137 is an artificial isotope produced by human. The first source of the Cs-137 became the nuclear tests and attacks used in the World War Two. In the 1960s (related a study of nuclear weapons) there were found out storing of Cs-137 in the surface soil layers. Even the peaceful use of the nuclear energy could cause the nuclear crash accompanied by a leakage of radioactive substances. The most tragic crash was an explosion of the nuclear power station Chernobyl in Ukraine. That crash contaminated the whole Ukraine and close states, but also Scandinavia. The spread of the Cs-137 depended on the rainfall and the air flow. Human has been affected by the radioactive elements even after the long time since the crash. Forest ecosystem seems to be the place with the largest amount of Cs-137 located. The Cs-137 may get into the human body though food; it has a very long half-time (30ys), it is stored in the top soil layers and through the root system of plants gets into the plants or mushrooms. The aim of this thesis is to determine and compare the content of the Cs-137 in the selected commodities in the forest ecosystem of Šumava using semiconductor gamma spectrometry. The research question was specified: Is the content of the Cs-137 in the selected commodities of the Šumava forest area significantly different? Based on an analysis of literature and consultation with the State Office for Nuclear Safety there were chosen areas, where was the highest fallout of radioactive elements. Therefore I sampled the area called Kvilda, Zadov and Churáňov. Further locations with the commodities of the forest ecosystem are Bavorov, Svinětice and Baranaviči. There are samples of soil, moss, spruce bark, cones and lichen. Not all commodities could be collected in all locations because there were picked in a small area and not all commodities occurred there. To determine the mass activity of the Cs-137 samples I used a semiconductor gamma spectrometry. The obtained spectra were evaluated through software GAMAT. The range of the values of mass activity of the Cs-137 in all samples is between 3-700 Bq.kg-1. The highest activity was measured in soil, where values reached up to 700 Bq.kg-1. High activity was also measured in moss in Kvilda, 513 Bq.kg-1. Samples of spruce bark, cones and lichens have low values activity. It was not reached out the value of 300 Bq.kg-1. Answer to the research question is that contamination of Sumava Cs-137 in selected commodities forest ecosystem is significantly uneven.
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Independent monitoring of Nuclear power plant Temelin environs by Regional centrum of SONS České Budějovice. Project of independent monitoring NPPTE in the case of Emergency incident.
ZEMAN, Karel
The State Office for Nuclear Safety (SONS) and the National Radiation Protection Institute (NRPI) are involved in independent monitoring of surrounding areas of nuclear power plants (NPPs), in accordance with the Czech legislative requirements (Decree No. 319/2002 Coll. on radiation monitoring network (RMS), as amended by Decree No. 27/2006 Coll.). The monitoring includes surveillance of environmental samples, in which radionuclides can be detected in case of emergency event, i.e. radioactivity release from the NPP. Another part of the monitoring is measurement of photon dose equivalent, continuously in the air (early detection network - SVZ) or using thermoluminescent dosimeters (TLD) placed in SONS monitoring points in the NPP vicinity. Environmental sampling and evaluation of photon dose equivalent in the air is carried out in regular intervals. The 137Cs and 131I activity is measured by gamaspectrometry method used with Gamat evaluation program, according to SONS internal procedure (VDMI). Tritium activity in surface water is measured by liquid scintillation spectrometer Beta TriCarb made by Canberra Packard Company, according to methodology CSN ISO 9698 (757635). Evaluation of dose equivalent rate is carried out continuously by LB 6360 proportional probe and LB 6500-3 Geiger-Muller tube located in RC Building in Ceske Budejovice. TLD evaluation is carried out by NRPI laboratory in Prague and the results are sent to SONS RC Ceske Budejovice. Goal of this work is to provide a set of results of the independent monitoring in surrounding areas of Temelin NPP (ETE) carried out between 1999 and 2009, by determination of volume, mass or surface activity of environmental samples (137Cs and 131I) and spot samples of water (3H) taken from SONS monitoring points near ETE . The set of such results should provide a baseline reference values for normal (pre-accident) situations. Additionally, based on the long term of the ETE surrounding surveillance, it can be shown that the ETE operation represents no threat to the health of the critical population group, and that the radiation situation in the ETE surrounding is stable. It can be also shown that the ETE operator meets requirements and conditions of authorized limits for discharging radionuclides into the environment. Procedures and method of independent environmental monitoring in the ETE surrounding during emergency events can be proposed on the basis of many years of experience with proven methodologies, experience with sampling locations, staffing and organization of measurement.
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