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The present thesis covered statistical evaluation of the effect of the management method and the landscape cover on selected hydrochemical parameters of surface water. To obtain and evaluate the necessary data, a model zone was selected, located in the mountains of Novohradské hory. It consists of the upper and lower sub-basins of the stream of Bedřichovský potok, which is the left-hand tributary of the River Stropnice. The sub-basins differ in how management methods are practised locally. While the upper sub-basin generally consists of forests and permanent grasslands, the lower sub-basin has primarily arable land and, in some part, built-up areas. For this reason, it is possible to compare the two sub-basins and evaluate their effect on the selected parameters of surface water; these involved conductivity, concentration of unsuspended solids, total organic carbon concentration, total nitrogen, nitrate nitrogen and phosphate phosphorus. The results show and support a conclusion that surface waters in the lower sub basin, one that is utilised for agriculture, exhibit higher values of the parameters monitored than surface waters present in the upper sub-basin, one that features forest/grassland vegetation cover. It can be noted that arable land has a reduced retention capacity and is more prone to erosion due to its vegetation cover of lesser size; this is also the reason why it is not able to completely retain the desired substances on the agriculturally managed land. This results in deterioration of individual hydrochemical parameters in surface water, such as conductivity or nitrate nitrogen. The thesis is generally indicative of the importance of vegetation cover for the management of water in the landscape.

The aim of this Master thesis was to compare the presence of used preservation substances and basic ingredients in meat products made in regular and bio-quality. In practical part of the thesis, a polarization measurement was done with the aim to determine whether there is a quality difference between these two production qualities. The obtained data were subsequently processed and statistically evaluated. The statistical evaluation showed that the basic composition of meat products in regular and bio-quality is basically identical in percentage. Furthermore, the frequency of used preservation additives in different foods was statistically evaluated as well. In conclusion, food products in bio-quality showed 0.7 less additive content compared to regular food product, however, the difference was still weighed as statistically insignificant.

The work deals with differences in ecological and conventional production. It compares soil cultivation, nutrition and plant protection, yield and crop quality. It characterizes the harmful substances found in vegetables, the way they get into the plant and their effect on human health. It describes the control system and organizations dealing with food safety in the Czech Republic and in the world. In the practical part are compared the quantities of heavy metals (Pb, Cd, Cu and Zn) and nitrates in ecologically and conventionally grown two varieties of peppers from the land of ZF MENDELU and found in organic and conventional carrots and tomatoes from the trade network. In addition to zinc in the heavy metal content, no demonstrable difference was found. Zinc was clearly more organically grown. Nitrate content did not differ in organic and conventionally grown vegetables except for carrots. Carrots sold under the bio brand contained more nitrates than conventional ones. But it was still a harmless quantity.

The aim of this diploma thesis was a statistical evaluation of the impact of farming methods and the land cover on hydrochemical parameters of surface waters drainage patterns in Novohradské mountains and identify the possible impact of agriculture on the valuesof these parameters. The area for the evaluation is consist of lower and upper parts of the basin of Pasecký, Bedřichovský and Váčkový stream. Sampling sites include agriculturally cultivated land, but also forest ecosystems. The work is mainly focused on the following parameters: conductivity, nitrate nitrogen (N-NO3-), suspended solids (NL105) and phosphate phosphorus (P-PO43-), which are parameters causing eutrophication of water. The parameters changes were analysed for the years 2014 - 2017. Significant differences were observed in the all three streams in the water chemisms between upper and lower parts of the watersheds of conductivity and nitrate nitrogen (N-NO3-). The results confirmed that the farming has a significant influence on the water quality in the Pasecký, Bedřichovský and Váčkový stream although it is an extensive farming.

The bachelor’s thesis with the theme of „Study of possible sources of pollution in the selected part of the watercourse“ deals with possible sources of pollution of the selected part of Račický potok. The theoretical part treats the characteristics of surface water and their preservation including valid legislation. After that there are described the ways of surface water pollution including particular elements and substances, which contaminate water. The practical part deals with collecting of the individual samples in selected collection points and their laboratory analysis. As the magnitudes for the analysis were selected: the amount of oxygen dissolved in water, electrolytic conductivity, the reaction of pH in the water, nitrate nitrogen, nitrite nitrogen, total phosphorus. In another chapters the results are interpreted and discussed with the valid legislation. The evaluation of the analysis shows a deterioration of the quality of the water, which is in Odunec caused by releasing the sewage water right into the watercourse and the absence of phosphorus precipitation in ČOV Krhov. In the conclusion there are suggested possible steps for improvement of the water quality in the selected area.

This diploma thesis focuses on an analysis of the sources of pollution in the catchment area of the water source in Skalice nad Svitavou, which is used as a supply of drinking water. The theoretical part of the thesis describes the issues related to the given topic, as well as the area of interest and the water source. Field research was conducted in the catchment area of the water source, and samplings spots for monitoring water quality in the watercourse of Úmoří were determined, as the watercourse runs near the water source. Samples were collected every three months and, subsequently, analysed in the laboratory of ÚAKE AF MENDELU. The findings were evaluated according to the valid legislation. The water quality of the water source was also evaluated for the time period of the last five years. On the basis of all of these findings, protective measures were proposed to improve the protection of the water source.

The aim of the diploma thesis was a statistical evaluation of the impact of farming methods and the land cover on hydrochemical parameters of surface waters. The area for the evaluation is located in Novohradsko and consist of lower and upper parts of the basin of Vackovy potok and a lower part of Pasecky potok. The area was chosen to include different landscape managements (arable soil, forest and meadows). Due to this fact, it is possible to compare the impact of the management on values of the chosen hydrochemical parameters, which were conductivity, N NO3-, TOC, NL105 and the outflow. Based on the results, it is possible to say that the surface waters from the intesively farmed part of the basin of Vackovy potok have the higher values of all chosen parameters compared to the forest basin or the meadow basin. There was a trend of the increase of the outflow and the values N NO3- in the surface waters always one day after a heavy rainfall. Overall, it is possible to claim that the arable soil has reduced abilities of the retention. This is supported by the large water drainage from the agricultural area.

The master thesis deals with influence of system of water reservois and farming on suface water quality in catchment Košín stream in the Tabor region. There were investigated effect on suface water quality of several watercourses flowing through farmland with markedly different land cover, farming, size of catchment area and different water reservoirs. The fundamental hydrochemical parameters such as content of nutrient, inorganic and organic carbon and undissolved substances were monitored. The water samples were collected from permanent sampling points during the growing season. The investigated compounds were determined in the laboratory by titration, gravimetry and spectrophotometry. Mean, median, interquartile range were determined within the basic descriptive statistics and the data were statistically processed by nonparametric tests. Results showed particularly significant influence of the littoral vegetation and wide strips of tree vegetation as an effective filter, which prevent pollution of surface water by nutrient runoff. In some cases, the land cover was reflected positive impact of vegetation on reducing contamination of the water above the level specified by legislation, therefore vegetation is great importance in the fight pollution of waterways. From the obtained data it is obvious that influence of anthropogenic pollution on surface water is very important, but appropriate land cover can minimalize this impact.

In this thesis, I focused on the cultivation and fertilization of barley and its use as a food supplement called "green barley". Nowadays people eat unhealthily, they do not diet, their food intake consists of a few essential nutrients and this leads to various illnesses and diseases. Green Barley is one of the ways how to replenish essential nutrients, such as vitamins, minerals, enzymes and others. Its regular use can achieve better physical condition and health and it also prevents from various diseases such as anemia, cancer, heart disease, blood vessels and skin diseases etc. The aim of this study was to figure out the best way of cultivation and fertilization of green barley. One of the best methods is practiced in the US, where green barley is grown on dried-up freshwater lakes where there is a very fertile soil and green barley can grow in ecological way. In the Czech Republic, it is better to cultivate green barley in conventional agriculture environment because the soil is fertile and there is a little need to fertilize it. If green barley in our area grew in ecological way, it would increase the nitrate content in the plant due to nitrogen-potassium fertilizer manure. The plant is not able to convert all the nitrogen in organic substances and redundant nitrogen remains in the plant in the form of nitrates.

The thyroid carcinoma incidence has currently multiplied and the largest increase was recorded for thyroid papillary carcinoma. The aim of this work is to discuss factors increasing the risk of thyroid carcinoma. The only confirmed risk of developing this form of carcinoma is ionizing radiation mostly in connection with nuclear attacks and nuclear power plants disasters. Other risk factors include iodine intake and the influence of nitrates, both of which act as separate risk factors and also as factors increasing the risk potential of ionizing radiation. Thyroid carcinoma occur 3 times more frequently in women, therefore the risk factors specific for females, such as estrogens, assisted reproduction methods, pregnancy and hysterectomy, are also discussed. Hypothyroidism and Hashimoto's thyroiditis have a significant association with thyroid carcinomas while controversial factors are risky elements of lifestyle and nutrition (eg smoking, cruciferous vegetables, high glycemic index and body weigh index). A high incidence of thyroid carcinomas was found in volcanic areas in connection with the effects of heavy metals contained in lava. Another high incidence was recorded in the areas with low average annual temperatures. One of the reasons for the increase in the incidence of thyroid carcinoma is...

Autotrofní denitrifikace bakterií Thiobacillus (T.) denitrificans patří mezi alternativní metody odstraňování dusičnanových a dusitanových iontů z kontaminovaných vod. V procesu se využívá bakteriálně katalyzované redoxní reakce - oxidace elementární síry nebo některých jejích anorganických sloučenin generuje elektrony, které jsou za anoxických podmínek prostředí využity k redukci dusičnanových a dusitanových iontů až na molekuly plynného dusíku. V této práci byla sledována v laboratorním měřítku autotrofní denitrifikace bakterií T. denitrificans v průtočném systému, kde byla použita elementární síra jako náplň a zároveň jako zdroj elektronů pro redukci dusičnanových a dusitanových iontů. Tato kolona měla 80 % účinnost. Autotrophic denitrification using bacteria Thiobacillus (T.) denitrificans belongs to group of alternative methods of removing nitrate and nitrite ions from contaminated water - it is used the redox reaction catalysed by bacterial enzymes. The electrons are released by the oxidation of reduced inorganic supfur compounds and used for the reduction of nitrates and nitrites under anoxic conditions. The aim of the work was to describe autotrophic denitrification of T. denitrificans in flow-through system, where elemental sulfur was used as electron donor. This flow-through system had 80 % efficiency.

V této práci byla testována metoda stanovení dusičnanů ve vodách s využitím přenosného fotometrického analyzátoru Fotometr PF-12. Výsledky i samotná metoda byly porovnány s průtokovou injekční analýzou (FIA) a spektrofotometricky sledovanou simultánní neutralizační mikrotitrací. In this work, a method to determine NO3− using portable analyzer Photometer PF-12 (Macherey-Nagel, Germany) for analysis of model solutions, and drinking as well as natural water was tested. The obtained results have been compared with those achieved by flow injection analysis and by spectrophotometrically followed simultaneous neutralizing microtitration.

The topic of the thesis is determination of concentration of dissolved solids in water and seasonal changes in surface water chemistry for specific affluents of Orlík water reservoir. Water samples were collected on regular basis and analysed in a laboratory during one season (November 2014 - November 2015). The thesis is focused on monitoring of changes in phosphate and nitrate concentrations, in particular. The results of analysis indicate that measured concentrations of substances at monitored locations reflect generally measured data within the region. Concentrations of NO3-N peak in winter to early spring seasons, therefore seasonal changes do occur; differences between locations have not been proven statistically. As for the parameter PO4-P within locations downstream pond systems no significant statistic differences were identified. Values of PO4-P concentration are not primarily associated with agricultural activities but rather with local sources existing within the catch basin. It has been concluded from testing water quality upstream and downstream fish ponds that pond management had no impact on quality of water within the monitored locations in 2015; respectively no additional phosphor and nitrogen load was imposed on Orlík water reservoir

This diploma thesis deals with clarification of an influence of rain discharge events on nutrients loss from drainage area and which rain discharge events are the main cause of the loss. Within the scope of this the influence of these episodes on drainage area of the Jenínský brook will be quantified, more specifically sub-drainage area J2. The thesis describes not only the circle of water in the nature, specification of rain drainage events origin, but also the very factors which influence the water drainage and the loss of nutrients caused by the drainage. Furthermore, the basic nutrients which appear the most often and in the biggest quantities in our waters are described, these being nitrogen and phosphor and last but not least what is described here is the total loss of nutrients in water during rain drainage events. The description of a drainage area itself and a water intake profile J2 follows. The water intake profile J2 was the source for processing the results. The results were processed by several computational methods, which were compared to each other in the end. The loss during 5 extreme rain events was calculated and so was their percentage representation in the total annual losses and the consecutive evaluation of the results.

The thesis deals with the issue of drinking water. The aim of the study is to evaluate quality parameters of drinking water in connection with legislation attending to this issue. The evaluation was conducted in nine agricultural subjects and analyzes of drinking water were determined and evaluated. Microbiological and hydrochemical indicators of drinking water were compared within the year 2015. Regarding microbiological indicators, coliforms, Escherichia coli, enterococci, psychrophilic bacteria were followed. Ammonia nitrogen, nitrate nitrogen, phosphate phosphor, total inorganic carbon, total organic carbon, total carbon, total nitrogen, pH, conductivity were followed regarding hydrochemical indicators. The final values showed exceeded values of the microbiological indicators at five sampling sites according to applicable legislation. Furthermore, threshold values of total organic carbon were exceeded in all tested agricultural subjects and also values of nitrate nitrogen in drinking water were increased at three subjects evaluated throughout the year.

The objective of this research was to investigate the effect of nitrification inhibitors (dicyandiamide and 1,2,4 triazole) on the content of nitrate and ammonium nitrogen in the soil and the effectiveness of nitrogen-sulphur nutrition of maize. The research was conducted in field small-plot experiment with maize on Haplic Luvisol with dominance of clay fraction in experimental years 2012 to 2015. The dose of nitrogen in all experimental treatments was 160 kg*ha-1 and was applied at one shot or split in three partial doses. Soil samples from all examined treatments were taken from three soil depths (0.0-0.3 m, 0.3-0.6 m and 0.6-0.9 m, respectively) by probe rod in 4- 5 week intervals. Achieved results indicate that on the average of four years and three depths of the soil profile, application of nitrification inhibitors contained in fertilizer ENSIN considerably reduced portion of nitrate nitrogen from the content of mineral nitrogen in the soil by 7-32 relative %. The application of fertilizer ENSIN considerably increased content of ammonium nitrogen in the soil by 10-59 relative %. A favourable effect on increase of ammonium nitrogen content and reduction of nitrate nitrogen content was found out in spite of the fact that in this treatment the total dose of fertilizer was applied at one shot., V pestovateľských rokoch 2012, 2013, 2014 a 2015 bol založený maloparcelkový poľný pokus s pestovaním kukurice siatej na stredne ťažkej hnedozemi s prevahou ílových častíc na lokalite Horné Semerovce. Pred sejbou kukurice sa z pôdneho profilu 0,0-0,3 m a 0,3-0,6 m odobrali pôdne vzorky k agrochemickým analýzam. Cieľom výskumu bolo skúmanie vplyvu inhibítorov nitrifikácie (dikyándiamid a 1,2,4 triazol) na obsah dusičnanového a amónneho dusíka v pôde a efektívnosti dusíkato-sírnej výživy kukurice siatej. Dávka čistého dusíka vo všetkých pokusných variantoch bola 160 kg*ha-1. V poľnom pokuse boli použité nasledovné dusíkaté hnojivá: liadok amónny s dolomitom LAD 27 (27% N), dusičnan amónny + síran amónny DASA 26/13 (26% N, 13% S) a ENSIN s rovnakým obsahom živín ako hnojivo DASA 26/13, obsahujúci dva inhibítory nitrifikácie. Inhibítory nitrifikácie dikyándiamid (DCD) a 1,2,4 triazol (TZ) sú priamo začlenené do granúl hnojiva ENSIN a tvoria jeho neoddeliteľnú súčasť. Hnojivá LAD 27 a DASA 26/13 boli aplikované 3-krát delenou aplikáciou pred sejbou kukurice, počas sejby kukurice a pri výške rastlín kukurice 0,3 m. Hnojivo ENSIN bolo aplikované jednorazovo pred sejbou kukurice. Každý variant bol štvornásobne opakovaný a plocha jedného opakovania bola 100 m2 (20 m x 5 m). V pokuse bolo 16 parceliek o celkovej výmere pokusu 1 600 m2 (4 varianty x 4 opakovania = 16 parceliek x 100 m2 = 1 600 m2). Pôdne vzorky zo všetkých skúmaných variantov sa odoberali z pôdneho profilu 0,0-0,3 m, 0,3-0,6 m a 0,6-0,9 m. Počas vegetácie kukurice sa uskutočnilo 6 odberov pôdnych vzoriek v 4-5 týždenných intervaloch až do zberu kukurice v pestovateľských rokoch 2012-2014. V pestovateľskom roku 2015 sa uskutočnilo 5 odberov pôdnych vzoriek počas vegetácie kukurice. Najnižšie hodnoty amónneho (N-NH4+), dusičnanového (N-NO3-) a anorganického dusíka (Nan) boli na kontrolnom nehnojenom variante vo všetkých pokusných rokoch. Relatívne vyššie obsahy dusičnanového dusíka oproti amónnemu dusíku v pôde sa nachádzali pri aplikovaní hnojív LAD 27 a DASA 26/13. Pri aplikovaní hnojiva ENSIN sa prejavila inhibícia nitrifikácie postupným uvoľňovaním amónneho dusíka, čo spôsobilo vyššie obsahy amónneho dusíka ako dusičnanového dusíka hlavne v mesiacoch máj až júl. Najvyššie obsahy amónneho dusíka a zároveň aj obsahy anorganického dusíka počas celej vegetácie boli na variante s hnojivom ENSIN. Dosiahnuté výsledky ukazujú, že v priemere štyroch pokusných rokov a troch hĺbok pôdneho profilu, aplikácia inhibítorov nitrifikácie v hnojive ENSIN výrazne znížila podiel dusičnanového dusíka z obsahu anorganického dusíka v pôde o 7-32 relatívnych %. Aplikácia hnojiva ENSIN výrazne zvýšila obsah amónneho dusíka v pôde o 10- 59 relatívnych %. Priaznivý vplyv na zvyšovanie obsahu amónneho dusíka a na znižovanie dusičnanového dusíka v pôde bol zistený, aj napriek skutočnosti, že celková dávka hnojiva ENSIN bola aplikovaná jednorazovo pred sejbou kukurice.

This thesis deals with the evaluation of concentration levels of phosphates, nitrates and other parameters (pH, conductivity, suspended solids, alkalinity, total carbon, inorganic carbon, total organic carbon and total nitrogen) in fishpond systems at Tabor. Further was to consider the difference in value depending on the age of the systems and agricultural activities in their vicinity. Samples were taken in season 2015 Liderovické pond system (2 sampling points at the top of the system, one sampling point in the outflow from the system), Radimovická pond system (one sampling point at the top of the systém, one sampling point at the outlet of the system) and Jordan ( one sampling point at the outfall of the pond). The highest differences were found in the values of conductivity from 279 S.cm-1 to 1230 S.cm-1, the values of total carbon from 18.75 mg.l-1 to 67.33 mg.l-1, and the values of suspended solids from 1 mg.l-1 to 117.33 mg.l-1. The gradual increase in the value of NO3-N and PO4-P was registered during the season with Jordan. Based on the results we can say that the older (Radimovická system) showed higher levels of total carbon and younger (Liderovická system) showed higher NO3-N depending on land use in the surrounding area.

This diploma thesis deals with the comparison of the development of nitrates and phosphates in various regions of the Czech Republic. The thesis contains of the description of the circulation of groundwater and its importance to the human society, the circulation of nitrogen and phosphorus and their occurrence in waters. Further, this thesis incorporates the description of the development and the way of observation of the concentration of nitrates and phosphates in groundwater. The selection of observational objects and used methods for the evaluation of the concentrations are described in the thesis. The aim of the thesis is the determination of trends of the concentrations of nitrates and phosphates during time periods and the statistical evaluation of the progress of the concentrations in regional cities of the Czech Republic. The next part of the thesis deals with the spatial analysis of the concentrations of nitrates and phosphates in the region of České Budějovice. This area was chosen for its great amount of the observational objects with a long time period of measuring.

The opening part of the thesis and literature review focused on familiarization with the issue of nitrates in water sources. In particular, the divorced anchoring issue of nitrates in both Czech and European legislation. Following the interpretation of the possible hazard occurrence of nitrate in drinking water. In the next part of the thesis deals with a specific locality - spring area I. and II. of water conduit Březová nad Svitavou. Here is described area of interest with a focus on hydrological, geological, pedological and climatic conditions. In the last part there are processed and evaluated the data, both in dependence of the concentration of nitrates and level height and dependence on the type of culture grown in the vicinity of boreholes. It was also evaluated the effects of atmospheric precipitation on level height in boreholes. In conclusion there are given possible measures to higher incidence of nitrate concentrations in boreholes could prevent. In the appendix part there is documented and described surroundings individual boreholes the degree of protection and economic use of land in the vicinity of boreholes.

The Riverbank Filtration (RBF) water supply system Karany has been affected by increasing NO3- concentrations during recent decades. This thesis deals with flow and chemical composition of groundwater in Skorkov and Sojovice RBF systems, which are the most problematic ones according to their quality in long term. Twelve new groundwater wells (V1- V12) were drilled in study area in 2013. Data derived from the wells were used to improve the conceptual hdrogeological model of the area and I tried to specify information about the origin of nitrate pollution. The Groundwater level logging showed hydraulic connection between the river and the wells situated up to 130 m faraway from the river (V1, V2 andV10), which were also demonstrated by the short- term temperature fluctuations caused by fast penetration of surface water from The Jizera River during higher flow rate to wells. I compiled geological sections which show the geometry of The Quaternary fluvial deposits and groundwater level. The chemical analysis of groundwater showed that it is not possible to differentiate groundwater from the shallow part of The Cretaceous aquifer from the aquifer of fluvial deposits by major chemical components. The result of infiltration experiments showed higher permeability in the environment with grass cover (kv=...

The content of the bachelor thesis was the comparasion of chemical-physical parameters of surface waters in Novohradsko. The data, which were used in the thesis, were taken in 2014. Individual sampling points were differed in their management practices and types of ecosystem. The monitored parameters are associated with eutrophication: conductivity, pH, KNK4,5, nitrates and phosphates. Based on the results we can claim that the sampling points of agroecosystems reached higher values of the selected parameters. The biggest differences were detected in conductivity. The values of conductivity were oscitalled from 51,8 mS cm-1 to 164,4 mS cm-1.

This thesis deals with the evaluation of hydrochemical characteristics of groundwater (dripping water) in The Chýnov Cave and the subsequent statistical processing of the results. There were followed three sampling points, which were irregularly distributed in the cave system. Bicarbonates occured as the dominant anions in the dripping water. The dominant cation was calcium. Water can therefore be classified as bicarbonate - calcium. This corresponds with the expectations for The Chýnov cave location. There were also detected enhanced concentrations of nitrates and sulphates at sampling site Štola - this has long-term character and influences the quality of the underground stream of The Chýnov cave, which is directly connected to spring "Rutický" (source of drinking water for the town of Chýnov). Although a protective zone is declared over the whole territory of Rutice water resources, there is increased amount of nitrates and sulphates which probably has anthropogenic character and it comes from applied fertilizer and mineralization processes in arable land in the close surrounding of the National Natural Monument: The Chýnov cave.

Natural springs and small water sources have existed on Earth since prehistoric times, serving as natural waterholes. After the man had appeared on Earth, he started to take care of these water resources and thus, wells were created. They were often associated with legends about their healing power. In the course of time, the function of the wells has changed. First, hunter's wells and then agro-wells were formed and used for the cultivation of fields. Later, they also began to fulfil the function of pilgrimage and hiking points. This bachelor's thesis gives a list of wells in the surroundings of Brno Dam with a focus on the ones in which the water quality is very probably affected by human activities, such as by influence of agriculture, forestry or transport. The thesis deals with potential sources of threat for these small water sources and examines the factors affecting their quality and the relations among them. In its final part, it assesses the water quality of the selected wells on the basis of the carried out laboratory analyses, evaluates the risks related to its consumption and tries to answer the question, how these risks depend on the position of the wells.

The master thesis lists the basic effects of nitrogen transformation in soil (nitrification), subsequent leaching of nitrates from soil to water and the effects of eutrophication of aquatic environment on the human health. The results of this experiment show that the interaction of all three factors (fertilization, soil moisture, vegetation) has a significant effect on the rate of nitrification. Generally, the nitrification rate increases with fertilization, decreases with presence of vegetation and decreases with soil moisture decrease. The health risk of nitrates in water consists in their consumption and the subsequent development of methemoglobinemia (especially in young infants) and the formation of N-nitroso compounds (e.g.nitrosamines), which have carcinogenic and teratogenic effects. Nitrate together with phosphates also promote the growth of cyanobacteria and algae. Cyanobacteria can produce cyanotoxins causing several groups of diseases.

Environmental modelling is lately becoming to be one of the most important decision support systems. Hydrological models present significant potential for use especially in area of surface and groundwater protection. In the diploma thesis, the Soil and Water Assessment Tool (SWAT) was used to evaluate nitrate surface water pollution in nine catchments situated in Křivoklátsko protected area during the period of 2003 - 2010. Modelling process consist of assorted consequent steps. First the hydrological model of each catchment was created. Afterwards the sensitivity analysis was conducted to select most sensitive model parameters. Calibration process was carried out after the parameters selection using SWAT-CUP automatic calibration tool. Model results were visualized and evaluated. The results of the model suggested, that the area of interest was not widely endangered by nitrate pollution. Within each catchment the critical source areas of nitrate pollution were identified. It was observed that these areas are related with intensive agricultural areas. Nitrate leaching ranged from 6 kg.ha-1 to 10 kg.ha-1 per year in agriculture areas. Some areas exceed this amount. Nitrate loss from most of the area of interest ranged from 0 kg.ha-1 to 4 kg.ha-1 per year. Concentrations of nitrates in modeled...

This thesis is focused on the selected methods of calculating basic runoff on a small catchment basin known as the P6, which belongs to the basin Kopaninsky flow and assess the impact on the basic runoff concentration of nitrate nitrogen in the total runoff. The thesis also analyzes the total, surface and subsurface runoff with its detailed division. There are also described in detail the chosen methods used for the separation of basic drainage. There is shown their mutual comparison too. We dealt with the nitrogen in groundwater. The methods for separation of basic runoff are described with regard to the content of nitrogen compounds, which are practically the most common type of pollution of groundwater used as drinking water sources.

This work aimed to evaluate long-term changes of selected chemical and physical parameters of rainwater from their own rain gauge stations Stropnicko. Chemical and physical parameters influence the rate of loss of substance in the landscape through the soil environment. In particular, the amount and concentration of dissolved sulphates and nitrates, affecting the value of the current pH. Samples were taken from their own rain gauge stations Stropnicko. Names of stations from which samples were taken are Horní Stropnice, Nakolice, Paseky and Nové Hrady. Rainfall were measured between the years 2005-2011 and were subjected to chemical analysis.

The aim of this study was to examine content of nitrates as anti-nutritional factor in selected species of vegetable available in stores of Jindřichův Hradec. The study was carried out in years 2010 and 2011. Number of analysed samples reached 206. Due to the very wide range of vegetable diversity on the market the study was focused on basic categories. The green-stuff were represented by Chinese leaves and Iceberg lettuce, the root-vegetable by carrot, parsley and radishes. Finally there were put in test turnip cabbages and potatoes. The lowest amount of nitrates was determined in samples of root-vegetable except radishes and potatoes. Parsley contained 452 mg of NO3-.kg-1, carrot 241 mg NO3-.kg-1. The average of nitrate concentration in potatoes was 230 mg NO3-.kg-1. The other side of the scale occupied turnip cabbages containing 1982 mg NO3-.kg-1 in average.

This Bachelor thesis is aimed to clarify the hydrological cycle, hydrological balance, groundwater hydrology, the selected basic baseflow separation methods of comparing them and last but not least, nitrogen cycle, nitrogen, nitrates, ammonia nitrogen and nitrogen in groundwater. In the work there is also closely analyzed the total, surface and subsurface outflow and the detailed division. The methods of the groundwater baseflow separation are described with regard to content of nitrogen compounds., which currently create the most common type of pollution of groundwater used as drinking sources.

The subject of this thesis is a description of various types of mathematical models aimed at the spread of pollution in the river downstream and selection of the most suitable type of model and design the new one with using MATLAB. The application of the model is performed on Karlický creek, where it will be put into operation a new wastewater treatment plant Vysoký Újezd. Using the assembled model there are presented three simulation studies showing the dependence of time on the concentration of nitrate. These are:  Simulation of accident of the wastewater treatment plant Vysoký Újezd  Excessive intake of nitrate caused sheet erosion from adjacent agricultural land  Combination of both simulations Individual studies present the effect of nitrate on the water quality in Karlický creek, which falls into two categories of protection, Český kras area and Nature Reserve Karlické údolí. The aim of the above simulation studies is to demonstrate the spread of the nitrate into the various compartments along the entire length of the watercourse, and to show the loss of the nitrate over time and to compare the effects of point and diffuse sources of pollution. The model is calibrated according to the samples taken in Karlík creek during the period from 30 June 2008 to 31.12. 2009th . The results of...

This research project was aimed at monitoring the quality of drinking water that is supplied to the inhabitants of small villages. The quality of drinking water produced by small waterworks in South Bohemia, in municipalities Mazelov, Ortvínovice, Doubravka and Rábín, was studied. Sanitary analyses of drinking water samples carried out by the waterworks operators in 2004-2009 showed some variability in the concentrations of free chlorine, nitrates, pH, turbidity and the content of Escherichia coli in all the waterworks during the investigated period. The hypothesis assuming that the quality of drinking water produced by water treatment from small water sources is stable and that it does not vary in some key indicators, such as nitrates, the contents of Escherichia coli etc., throughout the year was not confirmed. The other hypothesis assuming that the number of small water sources used for public drinking water supplies decreases during the period was confirmed. The causes of these changes depend on many factors, such as the location and source of drinking water, the type of treatment plant, and, last but not least, the quality of service and economic potential of the waterworks operators play a negative role.

The object of this research was follow up the cumulation of nitrates in individual kinds of vegetables. Analysed was 240 samples of root crops, cole crops and potatoes distributed in the trade network in Humpolec in the years 2008 - 2010. The measurement results show that all the vegetables went beyond the nitrate permitted limit, according to a law n. 53/2002. The most frequently it was in potatoe samples (50 % samples). The next was a carrot (27 %), kohlrabi (25 %), broccoli (24 %) and celery (17 %). From aspect cumulation of nitrates is parsley unchallenged kind of vegetable. Permitted limit was transcendent in 10 % about less than 1 %. The origin of the vegetables was detected as well. Czech republic had the worst results (52,5 %) because of the high nitrate concentration in potatoes. It is grown by a domestic growers. Spain had 20 % in broccoli and kohlrabi. It is imported to our market. Although the high nitrate concentration in some vegetable samples the vegetable influence the human health in a positive way and it doesn?t make health hazard.

The influence of precipitation on runoff characteristics of tile drainage systems and nitrate concentrations in drainage water were evaluated in this thesis. The Jeninsky stream catchment is located at the foothill of Sumava Mountains near the border checkpoint Dolni Dvoriste. Extensive agriculture (pasture) is practised in the catchment as well as surrounding areas. Above mentioned evaluated characteristics were measured on two closure profiles of tile drained subcatchments. Discharges were measured continously, water quality was sampled forthnigtly. Evaluated hydrologic year 2007 was rich in rainfall {--} the precipitation amounted to 892 mm, which is classified as a wet year, despite of 41 days long dry period. Runoff characteristics don{\crq}t vary much in both subcatchments, due to similar area and land use on researched catchments. Long dry period did not cause zero discharges. The progress of nitrate concentrations in subcatchments is characterized by low variations in values. Relatively low values (90-percentil of nitrate concentrations in individual catchments belong to II. and III. class of water quality limits set by Czech legislative) occured in the catchment. These values correspond or slightly exceed values monitored on surrounding simirarly used areas, but are significantly lower than values monitored in areas, where intensive agriculture is practised. This confirms positive influence of grassing on nitrate pollution of drainage and surface water.

The bachelor thesis deals with the risks of chemical contamination of food and possible health risks for the consumers. Firstly, there is a general outline of foreign substances including the additives, which are added to foods intentionally, and contaminants. The contaminants are viewed as undesirable substances which occasionally occur in foods. They develop directly in the foods or penetrate into them from the outside during the basic stages of agricultural production, in stores, during transportation or during processing for culinary purposes, or due to environmental pollution. Such substances can have negative effects on human health. The second part of the thesis focuses on concrete contaminants - nitrates, nitrites and acrylamide. Nitrates and nitrites are both contaminants and additives. Their use as food additives is motivated by their sensoric and protective effects. The sensoric function is to ensure a permanent pink colour of smoked meat and other meat products. The protective function consists in inhibiting the growth of the microorganisms Clostridium botulinum and thus preventing the origination of dangerous botulin. The nitrates exist as contaminants mainly in foods of vegetable origin, penetrating them from soil and water due to nitrogen cycle in the nature. The acrylamide is a newly discovered food contaminant. It is considered to be a very dangerous substance as regards possible peroral exposure. The danger consists in its neurotoxic, genotoxic and possible carcinogenic effects. It originates in foods with a higher content of reducing sugars during the process of production or culinary processing if the temperature is higher than 120° C. The thesis should provide information for the public as consumers or providers of different food-processing facilities. Its main objective is to pinpoint some risks connected with the consumption of various foods and meals, and to eliminate the risks as much as possible or to avoid them completely.