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The effect of delimitation of land on the reduction of sediment transport
HUMPÁL, David
This Bachelor´s Thesis deals with sediment denuding and with its possible reduction in the agricultural landscape by means of delimitation and other erosion control measures. The introductory part is devoted to general characteristics of the sediment, and indicates the amount of sediment in each element of hydrological network in the Czech Republic and in the world. The following two parts describe causes and consequences of higher concentration of sediment in the water environment. Factors affecting sediment denuding into surface waters and the description of these factors are determined in the following part. The last two parts, which are the most comprehensive, deal with means serving to reduction of sediment denuding in the agricultural landscape in term of erosion protection, and possibilities of delimitation application to limit sediment denuding. The aim of this work is to identify and describe protective measures, especially delimitation measures, which are used to reduce sediment denuding in the agricultural landscape, while pointing out the consequences that are caused by sediment in the water environment, coming mainly from poorly protected farmland.
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Indirect speciation of mercury in soils and sediments with cold vapor atomic absorption spectrometry.
ŠPAČKOVÁ, Jitka
In the diploma thesis have been tested four extraction techniques for isolation of organic forms of mercury from sediments (liquid liquid extraction, microwave extraction in liquid liquid extraction, solid phase extraction and extraction with use of ionic exchange) followed by determination of mercury by atomic absorption spectrometer AMA?254. It has been achieved great results during liquid liquid extraction likewise ionic exchange extraction. Reached percents of orgHg were in accord with certified reference material for sediments CRM-580 and corresponded to 86,44 ? 16,63 %, resp. 87,01 ? 29,22 %. Thanks to a simple procedure, extraction speed and ease of determination of organic forms of mercury contain was first of all (in the first instance) verified a method with use of ionic exchange, whose principle and procedure is very elementary. This technique was applied to a number of real sediment samples collected from water tanks Jordan and Skalka. It was approved that this method has been presenting a suitable alternative to chromatographic methods or methods of electro?migration.
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Study of properties DET, a method for pore water for sediment sampling
JAROLÍMOVÁ, Zuzana
The aim of this thesis was find out chosen properties of DET (diffusive equilibration in thin films), method for pore water for sediment sampling. This properties were: 1)the time require for equilibration between: a)distilled water in gel within DET and pore water b)sample of pore water within DET and distilled water 2)the comparison of samples pore water sampling with DET and other method 3)determination of DET properties in practice
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The Content of Mercury and Lead in Sediments from Vltava River and Lipno Reservoir.
MAŘÍKOVÁ, Helena
The aim of this thesis was to define and evaluate the load of sediments by exposure of mercury and lead on the upper flow of the Vltava river and in the Lipno lake. To evaluate possible influence of the glass factory in Lenora for pollution of this area by toxic metals mentioned above. The literature survey refers about problems of mercury and lead content in fresh water and reservoirs sediments, the structure of toxic heavy metals and risks of their release in the enviroment, then in chemical composition of water reservoirs. It also engages in glass manufacturing problems in the glass factory in Lenora, especially the raw materials, which where obviously used for its manufacture. Experimental part describes profile of sampling points, working methods, used chemicals and results of individual analyses. Sediments of the Lipno reservoir and the upper flow of the Vltava river aren{\crq}t seriously loaded with mercury or lead, but in the sediments below Lenora was shown multiple increase of lead and mercury content in comparison with the background. Forest soils has higher mercury content in all localities in comparison with the sediments. On the contrary, the content of EDTA-extractable lead in soils is lower. Detected isotopic ratio of lead 206/207 and 208/206 in sediments of the Vltava river below the glass factory in Lenora have different signature in comparison with the signature of sediments from the Vltava river above the glass factory. On the contrary the signature of lead in all sediments of the Lipno reservoir showed values relevant to natural background of this locality. The structure which corresponds to the lead from the glass factory was also surprisingly detected in humic horizont of the forest soils in Lenora{\crq}s surroundings. The thesis was extended with fish samples from Lipno reservoir and their liver{\crq}s load by lead and mercury content. There were determined isotop ratio (signature) of lead in the fish, the izotop ratio of lead not corresponds to the lead signature from the glass factory in Lenora.
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New methods for sediment description – how to their "metabolism"
Jan, Jiří ; Borovec, Jakub
Volume of reservoir sediments is usually small comparing to volume of water, but there are i) important place of nutrient recycling of water ecosystems and, ii) there are a dynamic part of the ecosystem. Large number of tightly coupled processes in the sediments is dependent on seasonal development and changes of physical, chemical and biological conditions (temperature, DO concentration, microbial activity, current conditions, amount and quality of settling material). Modern methods for nutrient balance in sediments, rates of release/uptake of nutrients and pore-water profiles were shown.
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