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Influence of reservoirs on communities of river flow
Lavičková, Šárka ; Černý, Martin (advisor) ; Tátosová, Jolana (referee)
Construction of dams significantly affects the chemical, biological and physical properties of the flow below the dam. These changes include a decrease in the numbers of individuals one or more species, the complete disappearance of species, or the introduction of non-native species. Disruption of natural water flow also applies to animals, who have only one stage of their life (usually reproduction) connected with the aquatic environment, although they are not permanent residents. Also necessitate significant changes in the life cycles of native plants and animals near the regulated river. Basic principles of behavior impounded flow describes the concept of serial discontinuity, which assumes that the construction of the dam will break river continuum, which then causes changes in river communities. Undergoing significant change such as flow regime in the river below the dam, the most striking changes are caused by the flow hydroelectric power stations. In addition, a temperature change in the flow decreases turbidity and often the availability of nutrients, because the location of the dam with the usual outlets (high or medium) acts as a trap sedimentary particles of organic and inorganic origin. It is important but also the contact area of the river, for example, reducing the zaplavovaného...
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An acidification of fresh waters is not over
Beneš, Filip ; Tátosová, Jolana (advisor) ; Hardekopf, David (referee)
Acidification of freshwaters is a problem of many areas over the northern hemisphere from the half of the 20th century. It has been caused by industrial factories discharging emissions of sulfur and nitrogen oxides, from which originate acids by the photochemical reactions in the atmosphere. Acidic atmospheric deposition has caused disappearance of fish and the most aquatic organisms in streams and lakes. Acidic atmospheric deposition has also washed up not only the buffering basic cations (Ca2+ , Mg2+ , Na+ , K+ ), but also toxic aluminium (Al3+ ) ions from soils into the freshwaters. The maximum levels of emissions of sulfur and nitrogen oxides were observed in 1980s and since that time the emissions of sulfur and nitrogen oxides significantly dropped down. However, the recovery from acidification is not as fast as it could be expected. It is impeding by several processes. One of them is hysteresis or saturation of soils by sulfur and nitrogen, which are slowly washing up into the freshwaters in forms of sulfates and nitrates now. Another process is the oligotrophication of lakes, when the important nutrient - phosphorus - is precipitating by aluminium. There is the lack of food for organisms after that. Another processes slowing down the recovery from acidification could be bad forest management...
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Invasive water invertebrates in Czech Republic
Kolářová, Lucie ; Tátosová, Jolana (advisor) ; Dočkalová, Kateřina (referee)
An introduction of invasive species is considered to be one of the most actual problems of these days and is also related with water environment and water invertebrates. Occurences of many non-native species has been recorded in waters of the Czech Republic and these species can be divided into two groups. Species of the first group are invasive alien species - their ecological patterns (e.g. high growing rates, high reproductive capacity or ability to transfer exotic diseases) make their spreading more successful. North-American crayfish species (Orconectes limosus and Pacifastacus leniusculus), Dreissena polymorpha or Dikerogammarus villosus are the typical representatives of this group. The spreading of these species is very remarkable, since their introduction causes many harmful effects and has negative impacts on native fauna. However, the appearance of other group of water invertebrates has been found in our waters. These are also non-indigenous species, but their spreading is very inconspicuous - they do not reach high population densities and their invasion does not cause negative impacts on native fauna and ecosystems. The evidence of these harmless invasive species has been recorded thanks to the monitoring programs and we possibly wouldn't know about them without this monitoring. The...
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Possibilities to restore seminatiral meadows in post industrial sites.
Kolářová, Petra ; Frouz, Jan (advisor) ; Tátosová, Jolana (referee)
The post-industrial sites (brownfields) are sites which were devastated and abandoned by industrial production (generation areas, dumping grounds, mining areas…), but buildings and paved areas abandoned by agricultural production, too. On the other hand on these very disturbed places, primary succession, may leads to recovery of valuable ecosystems. It shows the potential of these areas for the restoration of valuable near natural ecosystems. One of the possibilities how to use these areas could became establishing species rich meadows rich, which could return to the meadow ecosystem his original function. They could benefit from oligotrophic status, at least some of these sites, too. The aim of this work is to summarize the information about factors which influence structure and diversity of meadows, their restoration and assess chance post-industrial sites utilization for the recovery of species rich meadows. Finally results of experiment about restoration of species-rich meadow ecosystems on mine spoil dumps in the surrounding of Sokolov are represented.
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Recent and subfossil chironomids as a tool for tracing of environmental changes in mountain lakes of glacial origin
Tátosová, Jolana
JOLANA TÁTOSOVÁ, Charles University in Prague Ph.D. Thesis, 2008 ____________________________________________________________________________________________________ ___________________________________________________________________________ Abstract The limnological research in mountain areas of Czech Republic and Slovakia have a long tradition at our workplace, and our hydrobiological team has participated on many international projects focused on study of mountain lake ecosystems. Since 2000, I have become a member of this team and I have directed my research activities on the benthic fauna of mountain waters, especially on chironomids. They represent the most numerous and diverse group of benthic communities in the waters of mountain areas. As the life and geographical distribution of chironomids are controlled by many environmental parameters - temperature, food availability, concentrations of dissolved oxygen, pH, salinity, heavy metals and other pollutants, they can be very successfully used for tracking of environmental changes and effects of climatic variability on mountain lake ecosystems. The investigation of mountain areas has also its foundation. High altitude lakes represent very unique and vulnerable aquatic ecosystems. At the present time of very strong influence of human activity, these...
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Ecohydrological survey of river habitat quality - application to study area of the Zbytinsky brook catchment
Bímová, Tereza ; Matoušková, Milada (advisor) ; Tátosová, Jolana (referee)
Eco-hydrology represents a new approach to managing and protection of water bodies. Creates a new option of protection, revitalization and use rivers. Essential components in assessing the quality of streams are biological, hydromorphological and physical-chemical elements. This study is mainly focused on the review of the ecohydrological research in the upper Blanice river basin. Introduction is short overview of the current valid legislation of the European Union and the Czech Republic which creates a basic framework for assessing the ecological quality of streams. The aim is to summarize existing knowledge and assessment of surface water quality in terms of chemistry based on available data. The territories concerned are catchments of Zbytinský stream and Tetřívčí stream.
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