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Vztah revitalizací vodních toků a rekreace v krajině
Blažková, Kateřina
This thesis explores the relationship between the revitalization of watercourses and recreation in the countryside. The literature search analyses and describes the issue of the modification of watercourses in the urban landscape, and discusses the examples of good and worst practice of implementation in the Czech Republic as well as abroad. The practical part characterises the model locality of the Blanice River in Vlašim. The recreation effect of the revitalizations carried out is evaluated in the model locality and other selected examples of rivers in the Czech Republic and it also includes the public preferences method the questionnaire survey method, guided interview method, which focuses on the awareness of the population about the modifications of the watercourses. Using SWOT analysis, the factors of external and internal environment of the recreation potential are determined in the model locality. Based on the findings, the conclusion of the paper suggests some measures for improving the recreational conditions in the model locality.
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The occurrence and interactions of iodine in a natural environment, focused on the hydrosphere.
ŠEDA, Martin
Iodine is an important element essential for higher animals. A large part of the global human population suffers from a lack of iodine; elucidation of transfer and mobility of this element in the environment, water, soil, air and in organisms is thus very important. The aim of this work was the elaboration and optimisation of the method for determination of very low concentrations of iodine in the waters. The mass spectrometry with inductively coupled plasma (ICP-MS) technique was used. It has been shown that using of different filter types during sample preparation had no significant effect on the content of impurities in the filtered sample. Antimony was recommended as an internal standard, despite commonly used elements (indium or tellurium). Samples were not preserved because nitric acid caused volatilization of iodine from the sample and the addition of aqueous ammonia had no significant effect. The optimised method was tested on several groups of water samples, including precipitation, surface water and lysimetric waters. From autumn 2009 to summer 2010, a part of the Blanice River (Šumava Mountains, South Bohemia) was sampled. The average content of iodine in samples ranged from 1.48 ? 0.30 ?g?dm-3 (April 2010) to 3.05 ? 0.38 ?g?dm-3 (July 2010). The average content of iodine in samples from all tributaries of the Blanice River ranged between 2.52 ? 1.63 ?g?dm-3 (March 2010) and 3.67 ? 1.37 ?g?dm-3 (July 2010). The concentration of iodine in the monitored surface waters did not change significantly along the flow of the river. The other two streams were sampled near Rapotín village (Jeseníky Mountains, north Moravia). The average contents of iodine were as follow: Annov (upper stream) 1.60 ? 0.65 ?g?dm-3, Annov (lower stream) 1.88 ? 1.18 ?g?dm-3, Salaš (upper stream) 1.77 ? 0.92 ?g?dm-3, Salaš (lower stream) 1.42 ? 0.58 ?g?dm-3. Generally, the data showed that considering iodine, the area of Šumava had slightly higher levels than those observed in the Jeseníky Mountains. Precipitation collected in the South Bohemia (Arnoštov village and city of České Budějovice) and in Jeseníky (Rapotín) contained less iodine compared to surface waters, and rarely exceeded 3 micrograms per liter of water. The situation has changed in the spring of 2010, because of the occurrence of volcanic dust and ash over the Czech Republic. This volcanic cloud came from the sudden activity of the Eyjafjallajökull Volcano (Iceland). In the mentioned period, the contents of iodine in precipitation were increased several times at all sample collection sites. This is an indirect evidence that iodine could be released during volcanic eruptions and transferred over long distances through the atmosphere. It turned out that the wastewater treatment plant can eliminate iodine in wastewater only partially. However, the wastewater treatment plants in the monitored region were too small to evaluate the overall impact on the environment. The maximum iodine content at the outlet of the wastewater treatment plant Prachatice town (South Bohemia) was 28.5 ?g?dm-3, which is several times higher than natural levels in the Živný stream, to which the treated water flows. Lysimetric water samples were collected from lysimeters installed in three nearby plots in Arnoštov village (Šumava, South Bohemia). The highest concentrations of iodine were found on plot where cattle were grazed. These values were significantly higher (average 4.38 ? 1.74 ?g?dm-3) than those obtained from a site used as hay meadow (average 2.69 ? 1.19 ?g?dm-3) or an untreated meadow (average 2.25 ? 1.39 ?g?dm-3). Iodine therefore probably originated from the urine and feces of grazed cattle. This thesis contributes to the total knowledge of iodine, particularly to the part concerning determination of iodine in the hydrosphere.
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Migration permeability of fish pass on the river Blanice in region of urban area Zábrdí
KNÍŽEK, Jonáš
The purpose of my diploma thesis was tracking of new build fish pass on upper part of the Blanice river in cadastral area of Zábrdí.This fish pass is situated in area up stream from road bridge in village Zábrdí.For the data collection it was used a direct fishing of fish by portable electric unit.Direct fishing were carried out on 50 meters section under fish pass and in fish pass itself.Catching of fish was carried out in period from January to October 2008. There was realized total 10 catches .For a evaluation of migration permeability was used 336 pieces from 6 fish species,concretely it was Salmo trutta m. fario, Thymallus thymallus , Cottus gobio , Leuciscus cephalus, Leuciscus leuciscus, Lota lota, which was caught in tracked section of Blanice river ( 50 m section towards body of weir ) and 105 pieces from 4 fish species (Salmo trutta m. fario,Thymallus thymallus , Cottus gobio, Lota lota),caught in a body of fish pass. Of these results specific and size characteristics were determinated.Caught fish was determinated,measured and returned to aquatic environment.
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Seminatural spawning of brook minnow
FIDLER, Petr
The main subject of this experiment was to explain the behaving of the minnow during its reproduction, the preferation of the spawning substratum, the length of the incubation of eggs, the evolution and the growth of the juvenile and the fry. Brood fish were taken by elektrical unit in the Blanice river, in the area between the railway bridge and the weir in the village of Blanice. These were put into the experimental pond of 75 square metres. There were two spawning processes. The first took place on 10 June , the fry hatched after ten days and in the next ten days it could be found all over the pond looking for food. In the selection of the substratum the gravel (of the size of 2-5cm) was prefered at all. The standard length of the fry at the end of the process of breeding (after a hundred days) was 39{--}48 mm (the amount of 800 individuals). The second spawn took place on 11 August. The fry hatched after eight days and the next week it was hidding in the substratum and consuming yolk sack. The standard length at the end of the breeding was 18{--}26mm. The ammount of the breeded fry was 350 individuals.
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