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Manipulation with flow rates in water bodies - the possibilities for inhibition of cyanobacterial blooms development
Maršálek, Blahoslav ; Šejnohová, Lenka ; Vinklárková, Darina ; Plotěný, Miroslav ; Jančula, Daniel
If we compare the sediment capping by active barriers to protect the phosphorus release from sediments with other technologies of manipulation with methods of water discharge, it is clear, that by well-considered manipulations with water discharge, it is possible to reach the same (comparable) results with lower costs and with lower ecotoxicological and limnological risks. By the manipulation of water level, it is possible to reduce cyanobacterial bloom development as supplemental or supporting measure, but the effects may differ in different water bodies and thus it must be consulted always with specialists.
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Changes in water quality in outdoor swimming pools and swimming areas during the summer season
MARŠÁLKOVÁ, Alena
Good quality of bathing water is an increasingly important factor taken into account when we choose summer vacations, a place to stay for a weekend or a weekend trip destination. In the Czech Republic, bathing waters may be divided according to the legal status into outdoor swimming pools, surface waters used for bathing (swimming areas), other water surfaces or artificial pools. In my thesis I dealt only with outdoor swimming pools and swimming areas. The difference between them lies in the fact that outdoor swimming pools have their own operators who monitor water quality and provide other services in the waterside. Usually there is a fee charged. Swimming areas have no operators and water quality monitoring is placed under the responsibility of regional public health authorities. In the Czech Republic, at present, 188 outdoor swimming pools and swimming areas have been monitored on a regular basis each bathing season. For my research I chose four sites located in the South Bohemian region and four sites in the South Moravian region. For each of these eight sites, I collected results of laboratory analyses, including categories of water quality in bathing seasons of the past five years, it means from the year 2005. With these obtained data I assessed the water quality development both during the bathing season of 2009 and its evolution over the past five years. On the basis of particular categories of water quality I also tried to compare water quality in the South Bohemian and the South Moravian region and also to compare water quality between individual sampling points in one locality. Another aim was to evaluate some measures and interventions made in order to improve water quality. I focused particularly on the pond Olšovec in the South Moravian region and the VN (water reservoir) Orlík in the South Bohemian region. The results do not show any prominent changes in water quality both during the bathing season 2009 and over the past five years. Pronounced fluctuations in water quality were recorded only at certain locations during the 2007 bathing season. Not even between individual regions significant differences in water quality were found. The proportion of individual water quality categories in the two regions did not differ by more than 4%. We can therefore say that water quality in selected localities in the South Bohemian and South Moravian regions is comparable. As for certain measures and interventions implemented to improve water quality, it is important to focus also on the wider neighborhood of the locality, because it could also be a source of substances worsening water quality.
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