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The effect of pyrethroid based pesticides on fish
RICHTEROVÁ, Zuzana
Pyrethroids are ones of the most used pesticides worldwides. The widespread use and high stability of pyrethroids lead to the assumption of that their occurrence in the environment could be quite frequent. They can reach water ecosystem as pollutants. Residues of pyrethroids are not only detected in the water column, but also in sediments and in fish tissues. The first study was devoted to the product Nexide containing 60 g.l-1 of active substance gamma-cyhalothrin. Tested Nexide concentrations were 5, 25, 50, 100, and 250 µg.l-1. Early life stage test was used.Common carp (Cyprinus carpio) was tested. There were significant mortalities in all concentrations except the lowest concentration during the trial. The lowest concentration tested 5 µg.l-1 only caused a slightly increased mortality. This lowest concentration influenced the growth in length and weight negatively, decelerated ontogenetic development, and made the body surface of the individuals darker. Histopathology of individuals from this concentration revealed dystrophy in liver. Examination of kidney, intestine and gills did not show significant histopathological differences compared with control. The evaluation of selected parameters of oxidative stress demonstrated a significantly higher activity of detoxification enzyme glutathione-S.transferase (GST) and a significantly lower activity of defensive enzyme glutathione peroxidase (GPx) compared with the control group. The other examined parameters of oxidative stress such as catalase (CAT), glutation reductase (GR), and lipid peroxidation determined by using the thiobarbituric acid-reactive substances (TBARs) were comparable to the control group. Changes in oxidative stress parameters suggest that exposure of the organism to the product Nexide in the given concentration leads to dysbalance of defensive enzymes. The second study was devoted to the product Cyperkill 25 EC containing 250 g.l-1. Tested Cyperkill 25 EC concentrations were 7.2, 36, 72, 144, and 360 µg.l-1. The procedure of the trial was the same as the preceded one. There were 100% mortalities in all concentrations except the lowest concentration during the trial. The lowest tested concentration 7.2 µg.l-1 allowed 90% of individuals to stay alive till the end of experiment. The lowest concentration influenced the growth in length and weight negatively and decelerated ontogenetic development compared with the control. Any individual exposed to this concentration did not reach juvenile stage until the end of the trial. Dark pigmentation was visible in 68% of these exposed individuals on the last day. Similar darkening was visible in individuals from higher concentrations shortly before death too. Histological examination did not revealed significant changes in intestine, liver, kidney, and gills compared with the control group. Evaluation of selected parameters of oxidative stress demonstrated significantly lower activities of GST, GR, and GPx. Activities of CAT and TBARS were comparable with the control group. Changes in oxidative stress parameters suggest that exposure of the organism to the product Cyperkill 25 EC in the given concentration could induce oxidative stress and interfere with the activities of antioxidant enzymes. The presented thesis summarises actual data about pyrethroids and their influence on fish. The demonstrated effects confirm high susceptibility of early developmental stages of fish to tested pesticides. When interpreting the results, we have to take into account the fact that studies showed this risk even on single pyrethroid substances. But water organisms are exposed to many other more or less toxic products and substances in a real environment. These xenobiotics could react with each other and their mixture could even potentiate negative effects. The performed studies also clearly show the significant differences in the sensitivity of embryonic and embryolarval tests.
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Geographical aspects of religion – comparison of the Czech Republic and Austria
Pecharová, Kateřina ; Kokaisl, Petr (advisor)
The purpose of my thesis is to map a development of religion, mainly christianity, and its different geographical aspects of the Czech republics and Austrian territory. I´d like to compare individual indicators and using questionnaires and interviews answer these questions:
Nakolik tyto atributy může zachytit statistika?
What are the main attributes of religiosity?
The extent to which statistics capture these atributes?
How does faith and religiosity vary from each other?
How much does actual rate of religiosity and real faith vary?
Do the statistics give us a realistic information about religion and its part in mentioned countries?
Why do the rate of religiosity in the Czech republic and Austria vary so much from each other considering that they are neighboring countries.
Are Austrians considering their high rate of religiosity really more religious than Czechs as an atheistic nation?
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Geographical aspects of religion – comparison of the Czech republic and Austria
Pecharová, Kateřina ; Kokaisl, Petr (advisor)
The purpose of my thesis is to map a development of religion, mainly christianity, and its different geographical aspects of the Czech republics and Austrian territory. I´d like to compare individual indicators and using questionnaires and interviews answer these questions:
Nakolik tyto atributy může zachytit statistika?
What are the main attributes of religiosity?
The extent to which statistics capture these atributes?
How does faith and religiosity vary from each other?
How much does actual rate of religiosity and real faith vary?
Do the statistics give us a realistic information about religion and its part in mentioned countries?
Why do the rate of religiosity in the Czech republic and Austria vary so much from each other considering that they are neighboring countries.
Are Austrians considering their high rate of religiosity really more religious than Czechs as an atheistic nation?
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A comparison of unemployment in various social groups
Urbanová, Věra ; Majerová, Věra (advisor) ; Petra, Petra (referee)
This diploma thesis has both a theoretical and a research section. In the theoretical part basic concepts related to the topic are defined and the unemployment of social groups vulnerable in the labour market that require increased attention in their inclusion are analysed. The empiric section comprises of research focusing on candidates of these social groups applying for a job. Furthermore, the research of the labour office's employees at the departments of the labour office (KoP ÚP ČR) is included. The acquired data is then evaluated and a conclusion formed as to how the current situation can be improved.
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Biotransfer of selected risk metals into plants and their accumulation and distribution in plant organs
Le Minh, Phuong ; Lachman, Jaromír (advisor)
Contamination of soils with heavy metals is one of the serious environmental problems threatening human being. Heavy metals are considered as the special hazard of soil pollutants because of the adverse effects on the plant growth, the amount, activity of useful microorganisms in soils and the quality of food. Regard to the persistent and toxicity, the heavy metals are toxic when we consider different kinds of pollutants in soils. In the soil, zinc (Zn), cadmium (Cd), lead (Pb) and mercury (Hg) toxicities frequently occur than the other metals because of their precipitation and sorption by the soil. It is a very dangerous situation because when these metals are taken up by plants, they can be transported to the food web and food chains.
In the present study, the accumulation of four heavy metals (mercury, zinc, lead and cadmium) in the whole grain of spring accessions of emmer, einkorn and common spring wheat cultivars and potato (Solanum tuberosum) is reported. Heavy and essential elements were monitored in potato cultivars in the exact field experiments and in hydroponically grown plants. The elements were determined by methods FAAS, ET AAS, and AMA (Advance Mercury Analysis). Statistical analyses were performed using SPSS 9.0 with the Tukey HSD (Honestly Significant Difference) test (alpha equal to 0.05).
In our study, the concentration of heavy metals decreased in the order zinc (Zn) > lead (Pb) > cadmium (Cd) > mercury (Hg) in the wheat grain. The comparison between three varieties of investigated wheat revealed that the emmer wheat was rich in zinc content (62.12 mg kg-1 dry matter), while the spring wheat had the lowest average concentration of zinc in the grain (40.99 mg kg-1 dry matter). Generally, the values of lead concentration in grain wheat varieties were low (ranging from 0.1268 mg kg-1 dry matter to 0.2950 mg kg-1 dry matter).
The concentrations of mercury in four typical growth stages of wheat (boot stage 10, heading stage 10.2 1/4 of head emerged, leaf-stage 10.2 and stage ripening 11 according to Feekes) were also determined. It has been shown that the concentrations of mercury in different wheat varieties were absorbed differently at different growth stages of plant. Stage 10.2 and leaf stage 10.2 showed the high mercury content (0.0152 mg kg-1 dry matter and 0.0214 mg kg-1 dry matter, respectively). Among individual varieties significant differences were determined.
Amounts of toxic and potentially toxic elements detected in investigated potato tubers are characterized by a large variability within investigated groups. Performing statistical analysis (one way ANOVA) showed that there were no significant differences between two investigated groups of samples (samples from Uhříněves and Valečov in the year 2013 and 2014) considering either one of investigated metals. Measurable levels of mercury were found in smallest amounts in all investigated potato samples comparing to other metals (Cd, Pb).
Plant cells compared to animal cells are characterized by the formation of cell walls. Plasma membrane or cell membrane is a biological active membrane separating the interior of cell from the outside environment. An adjusted method for isolation of protoplasts was developed and adapted for isolation of protoplasts from plant material (potatoes). In our experiment, the plants were grown hydroponically in the Research Institute of Plant Crops Prague-Ruzyně. If we examine the plant membrane, one option is to remove the cell wall by means of special mixture enzymes. Protoplasts were released in the dark at 25 degrees of Celsius for 18 hours. The 70 and 90 microns sieve was used to filter and then centrifugation for 5 minutes at 100 x g. All the steps were carefully carried out to prevent the damage or breakage of protoplasts.
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Application of mathematical models for simulation of hydrological conditions in selected streams
Kurková, Marie ; Vašků, Zdeněk (advisor) ; Michal, Michal (referee)
Flood is a natural phenomenon that occurs at different intensities and irregular time intervals. As to natural disasters, floods represent the greatest direct threat for the Czech Republic. They may cause serious critical situations during which not only extensive material damages are done, but may bring also losses of the lives of inhabitants in affected areas as well as vast devastation of cultural landscape including environmental damages. Important from the viewpoint of the elimination of potential threats and consequences of such events is the information issued by flood forecasting service about the character and size of flood areas for individual N-year flood discharges and specific flood scenarios. An adequate image of depths and flow rates in the longitudinal or cross profile of the watercourse during a flood event is provided by the hydrodynamic model. This is why the information obtained from the hydrodynamic models occupies a privileged position from the viewpoint of the protection of citizens' lives and mitigation of damage to their property. The first study is situated on the river Úhlava in meadows by Příchovice near the town Přeštice. The proposal of flood-protection measures is contained in Territorial control documentation. The documentation was elaborated on the basis of hydraulic calculations and experiences from the flood in August 2002. The mathematical model is practically used in the study of analysis of proposed flood-protection measures. The analysis is based on mathematical simulation of water outflow and water level on the river Úhlava. It is possible to use the non-commercial software Hec-Ras, version 3.1.1., for the simulation itself. One of the points of view of the possibility of using proposed flood-protection measures is total efficiency. The mathematical model is posssible to use as a basis of support for realization of proposed flood-protection measures on the river Úhlava in meadows by Příchovice within the grant programme "Program prevence před povodněmi II" under the control of the Ministry of Agriculture. In the second case the mathematical model is practically used in the study of hydrotechnical analysis of streams in cadastral unit. The analysis is based on matjematical simulation of water outflow and water level on chosen streams. It is possible to use the noncomercial software HEC-RAS for the own simulation. The analysis should be shown on dangerous places in the interest place. The mathematical model is possible of using to use as basis for revaluation of action in spatial plan or for view of the flood-protection measures in the village Mochtín. Basic input into the hydrodynamic models is represented by altimetry data. One of ways to obtain such data is through the method of aerial laser scanning (ALS) from the digital relief model (DRM). This method is considered one of the most accurate methods for obtaining altimetry data. Its bottleneck is however incapacity of recording terrain geometry under water surface due to the fact that laser beam is absorbed by water mass. The absence of geometric data on watercourse discharge area may perceptibly affect results of modelling, especially if a missing part of the channel represents a significant discharge area with its capacity. One of methods for eliminating the deficiency is a sufficient channel recess by means of software tools such as CroSolver. The third submitted paper deals with the construction of a hydrodynamic model using 5th generation DRM data, and compares outputs from this model at various discharges with a model based on the altimetry data modified by using the CroSolver tool. Outputs from the two hydrodynamic models are compared in HEC-RAS programme with the use of recessed data and with the use of unmodified DRM. The comparison is done on the sections of two watercourses with different terrain morphology and watercourse size. A complementary output is the comparison of inundation areas issuing from both model variants. Our results indicate that differences in the outputs are significant namely in the lower discharges (Q1, Q5) whereas for Q50 and Q100 the difference is negligible with a great role being played by morphology of the modelled area and by the watercourse size.
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The comparison of digital terrain model sources in GIS for hydrological purposes
Klempíř, Hynek ; Bašta, Petr (advisor) ; Gdulová, Kateřina (referee)
This thesis deals with comparsion of digital terrain models from different
sources processed in GIS for hydrological purposes. The diploma thesis is
composed from several parts. First part sis consist of characteristics related to
watershed and water flow, which are important for the understanding this work. The
thesis also describes digitial terrain model, his creation and methods for obtainig
digitial models. Then, there are described data sources from which is possible to
gain digitial models. Next chapter is dedicated to the coordinate system. The last
parts of this thesis describes drain alghorithms.
Characteristic of this area was collected on experimental watershed Modrava II
with the ESRI ArcGIS Desktop software that would mainly Spatial Analyst and
ArcHydro extensions.
The results of this diploma thesis can be concluded that the free digital terrain
model SRTM 90 is not suitable for small regions with diverse terrain structure. Thereason is a small resolution model. Other terrain models provided free of chargé are
sufficient even for small areas as the selected area of interest. Paid digitial models
can al lbe established for the area of interest as appropriate.
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Comparison of various methods monitoring insect diversity in sown flower strips and neighboring fields of winter wheat and winter oilseed rape
Kolařík, David ; Kazda, Jan (advisor) ; Josef, Josef (referee)
In this study we deal with comparison of insect monitoring methods on flowering strip, wheat and oilseed rape. The experiment is located at two study sites: Crop Research Institute at Ruzyně and Experiment unit of Czech University of Life Sciences in Uhříněves. The experiment was carried out in 2015.
To make monitoring we utilized sweeping net, Möricke yellow traps, transect counting and as a supplementary method we utilized light trap. Monitoring was done in 25 of June, 16 of July and 12 of August 2015. These dates were chosen because of flowering of the strip which was the most important issue in this study. As a result of this the insect diversity in other almost harvested variants was quite low.
The most important insect species quantities were collected from Möricke traps in all three variants. But this fact could be naturally based on the attractivity of the yellow color, so we can´t reliably say, if in out of bloom rape or wheat could be present this high amount of insect or if it is only being attracted by color of the trap from the neighborhood.
The second method with the highest insect occurrence was sweeping net. Again the highest species diversity was described from the flowering strip.
The lowest amount of insects was noted in transect counting. This method has (contrastingly to the others) disadvantage in the high possibility of fail to detect small insect, which are normally noticed by the other methods.
Light trap monitored about the highest species number, where the majority of species belong to order Lepidoptera. That sway this method was employed only to enrich the species diversity.
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