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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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