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Chironomid fauna of acidified mountain waters
Malá, Martina ; Tátosová, Jolana (advisor) ; Vondrák, Daniel (referee)
Acidification of freshwater ecosystems peaked in 1980. There were overall changes in the chemistry of surface waters. As a result, some fish and sensitive species of zooplakton and zoobenthos disappeared. After the peak, emissions of major pollutants (SO2, NOX a NH3) declined significantly, which started the process of recovery from acidification. Nevertheless, biological recovery proceeds very slowly and it is not clear whether it is a completely reversible process. Chironomids serve as a very useful tool to assess acidification and recovery processes, mainly due to their toletance and also sensitivity of species to low pH, concentration of dissolved oxygen, nutrient content and adaptability to changes in food supply. Chironomids have in general high adaptability of species to harsh conditions. Food supply and concentration of dissolved oxygen are likely the main factors which influence the assemblages of chironomids in freshwater ecosystems. Chironomids are suitable for use in surface water research and biomonitoring due to their world-wide distribution, high species diversity and density. In comparison to other families of zoobenthos there is far less studies of chironomid assemblages, because of demanding determination. The CPET method, which uses collection of pupal exuviae, has great potential...
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Periodic Water Bodies and Their Biota.
Bušová, Tereza ; Říhová, Dagmar (advisor) ; Škodová, Jana (referee)
This thesis is focused on a description of small periodic water bodies and their biota. These telms are formed as a result of heavy spring rains, floods, melting snow or the ground water level rising. They are formed on green parts, non-green parts or fallen parts of a plant (in that case they are called phytotelmes), in water-filled tree-holes (dendrotelmes), in fissures of rocks (lithotelms) or in various cavities, artificially created by human - in empty jars, water- filled tires, flower-holding vases in cemeteries etc. The thesis deals mainly with dendrotelmes and phytotelmes which are the most frequent, especially in tropics. It provides the information about their formation and animals that lives in these small habitats. Also, a taxonomical review of the main reported fauna was added for better orientation of the reader. The most common taxa which occur in temporary pools are families of mosquitoes (Culicidae), chironomids (Chironomidae) and ceratopogonids (Ceratopogonidae). There are also present other Dipteran larvae or larvae of scirtid beetles from the family Helodidae. Some of the animals living in the pools used different evolution strategies to be well adapted to deal with periodicity and drying out of the water bodies. Their overview is also included in this thesis. Furthermore,...
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Biodiversity of chironomid fauna in mountain lakes and streams influenced by acidification and recovery from acidification.
Černocká, Veronika ; Stuchlík, Evžen (advisor) ; Frouz, Jan (referee)
This thesis examines the influence of acidification on the largest group of macroinvertebrates in mountain lakes and running waters - chironomids. The diversity of chironomids has been associated with temperature, the concentration of dissolved oxygen in the water, the amount of nutrients, and also with the ability to survive in conditions (e.g. extreme pH) that are not suitable for other taxa. Because of this the family Chironomidae has become a dominant group of macrozoobentos in many assemblages affected by acidification. The Bohemian Forest lakes and the Tatra Mountain lakes belong to the most frequently studied locations, which were affected by acidification. The peak of acidification was in the 1980s. It turned out that, during the acidification, the number of chironomids changed and also the species composition of their assemblages. The main reason was a change of trophic status, which chironomids reflected more than a change of pH. A decrease in the number of species occurred after the pH dropped below 5. Until then, only their relative abundance had been affected. Chironomids are also influenced by the toxic effect of Al. The most important factor affecting chironomids fauna is not the value of pH, but the change of food supply. Acid stream food webs are often viewed as being...
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Chironomid fauna of acidified mountain waters
Malá, Martina ; Tátosová, Jolana (advisor) ; Vondrák, Daniel (referee)
Acidification of freshwater ecosystems peaked in 1980. There were overall changes in the chemistry of surface waters. As a result, some fish and sensitive species of zooplakton and zoobenthos disappeared. After the peak, emissions of major pollutants (SO2, NOX a NH3) declined significantly, which started the process of recovery from acidification. Nevertheless, biological recovery proceeds very slowly and it is not clear whether it is a completely reversible process. Chironomids serve as a very useful tool to assess acidification and recovery processes, mainly due to their toletance and also sensitivity of species to low pH, concentration of dissolved oxygen, nutrient content and adaptability to changes in food supply. Chironomids have in general high adaptability of species to harsh conditions. Food supply and concentration of dissolved oxygen are likely the main factors which influence the assemblages of chironomids in freshwater ecosystems. Chironomids are suitable for use in surface water research and biomonitoring due to their world-wide distribution, high species diversity and density. In comparison to other families of zoobenthos there is far less studies of chironomid assemblages, because of demanding determination. The CPET method, which uses collection of pupal exuviae, has great potential...
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Periodic Water Bodies and Their Biota.
Bušová, Tereza ; Říhová, Dagmar (advisor) ; Škodová, Jana (referee)
This thesis is focused on a description of small periodic water bodies and their biota. These telms are formed as a result of heavy spring rains, floods, melting snow or the ground water level rising. They are formed on green parts, non-green parts or fallen parts of a plant (in that case they are called phytotelmes), in water-filled tree-holes (dendrotelmes), in fissures of rocks (lithotelms) or in various cavities, artificially created by human - in empty jars, water- filled tires, flower-holding vases in cemeteries etc. The thesis deals mainly with dendrotelmes and phytotelmes which are the most frequent, especially in tropics. It provides the information about their formation and animals that lives in these small habitats. Also, a taxonomical review of the main reported fauna was added for better orientation of the reader. The most common taxa which occur in temporary pools are families of mosquitoes (Culicidae), chironomids (Chironomidae) and ceratopogonids (Ceratopogonidae). There are also present other Dipteran larvae or larvae of scirtid beetles from the family Helodidae. Some of the animals living in the pools used different evolution strategies to be well adapted to deal with periodicity and drying out of the water bodies. Their overview is also included in this thesis. Furthermore,...
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