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Phytoplankton of drinking water reservoirs in the Jizera Mountains, Czech Republic, in relation to treatability of water
Čermáková, Anna ; Hořická, Zuzana (advisor) ; Procházková, Lenka (referee)
The area of the Jizera Mountains (northern Bohemia) was significantly affected by acid atmospheric deposition in the second half of the 20th century. This mountain area has a very sensitive geology and is characterized by the predominance of spruce stands, naturally acidic shallow soils of podzolic type, large areas of peat bogs in the upper plateau, a rough climate, and a very high annual rainfall. The frequent heavy rains and a low infiltration capacity of soils brought about floods in the past, very dangerous for the populated foothills. , so in the early 20th century For that reason, a plan was proposed to construct a system of reservoirs for a flood protection of the area. In the 1970s, the need for new sources of drinking water increased in the area. The Souš retention and recreation reservoir was rebuilt to a drinking water reservoir in 1974, and a new drinking water reservoir Josefův Důl was bulit in 1982. Both the water bodies have had a dystrophic character since the beginning, and the Souš reservoir suffers from naturally high concentrations of aluminum. Due to the anthropogenic acidification, the reservoirs were fishless until brook charr (Salvelinus fontinalis) were successfully (re)introduced in the 1990s, and the diversity and numbers of the zooplankton were very low. The...
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Phytoplankton of the Tatra lakes: factors influencing taxonomic composition and biomass
Červenková, Lenka ; Nedbalová, Linda (advisor) ; Štefková, Elena (referee)
The aim of this diploma thesis was to describe species composition and biomass of phytoplankton in the Tatra Mountains lakes (Slovakia, Poland) and environmental factors influencing them. The surface layer of 89 lakes was sampled in September 2004. Flagellates from Chrysophyta, Dinophyta and Cryptophyta most frequently dominated the phytoplankton biomass. Lake in the same valley usually differed in their dominant taxonomic group as a result of different lake morphometry, catchment type and detailed geological structure. Based on the level of phytoplankton biovolume, the majority of lakes were ultraoligotrophic and oligotrophic, however, mesotrophic and even eutrophic conditions were recorded in some forest and meadow lakes. An allometric relationship between phytoplankton biomass and chlorophyll a was revealed. Specific chlorophyll content did not differ among taxonomic groups. Altogether 233 species were determined, the most diverse group were Chlorophyta. Species richness of lake was 3-46 and it was negatively correlated with altitude and positively correlated with lake area. The majority of species were rare both in term of biomass and number of lakes occupied by a particular species. Average local species biomass was positively correlated with regional distribution. The similarity of species...
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Extreme abiotic conditions as determinants of phytoplankton structure in high mountain lakes
Mihál, Martin ; Nedbalová, Linda (advisor) ; Hořická, Zuzana (referee)
There are many areas with extreme environmental conditions in the world. One of them are high mountain lakes which are located above treeline. Bachelor thesis presents the main abiotic conditions as determinants of phytoplankton structure in high mountain lakes. It has to cope with significant changes in light conditions and high intensity of sunlight during ice-free periods and with an important diminution of radiation by snow and ice cover. The thesis also discusses the influence of temperature, which is related to the duration of the ice and snow cover and a stratification of lakes. It characterizes local factors, such as topographic shading, morphology of lakes and character of basins, which affect chemical and physical properties of lakes. The thesis also mentions the impact of atmospheric deposition and other factors on nutrient concentrations in the water column. In addition, it discusses the adaptations of phytoplankton to environmental conditions, which include development of deep chlorophyll maximum, biosynthesis of protective compounds and nutrition strategy (mixotrophy). The thesis shows that there are many specific abiotic factors, which influence phytoplankton in high mountain lakes and all these factors interact. This results in a characteristic species composition with prevalence of...
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The impact of eutrophication on fish in running waters
Jeníšová, Karolína ; Horká, Petra (advisor) ; Frouzová, Jaroslava (referee)
Eutrophication belongs among be the most serious factors threatening freshwater ecosystems. Eutrophication is a result of excessive nutrient loading which comes mostly from both the point-source and diffuse pollution and agriculture, increased sediment loading from soil erosion, but also due to a presence of various types of impoundments, which, particularly in some areas, represent a significat part of nutrient supply. Although the effect of eutrophication on freshwater fish communities has been thoroughly studied in standing waters, very little attention has been paid to running water ecosystems. Among the processes with the most pronounced impacts on fish communities are increased phytoplankton growth and loss of macrophytes, low oxygen levels or anoxia, occurrence of toxic forms of nitrit and ammonia and elevated turbidity and subsequent light reduction. Whilst the diversity of fish communities is not usually affected, changes in structure of fish communities and decreased ecological quality has been detected with the increasing level of eutrophication. The most sensitive fishes are salmonids as they have high oxygen demands and are very sensitive to a toxic forms of nitrogen. Moreover they are visual predators highly affected by the increased turbidity of water environment. Percids are mainly...
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Dynamika fytoplanktonu kaprových rybníků
SVOBODA, Martin
The bachelor thesis deals with the dynamics of phytoplankton in the short-term time scale and compares it with the annual course of phytoplankton in two studied ponds. In August 2017, samples were taken from two ponds in South Bohemia, specifically from the Dehtář pond and the Kvítkovický pond in 5 respectively three depths. The phytoplankton biomass was determined microscopically. The short-term dynamics of the main phytoplankton groups is contained in graphs. Besides, a list of all designated cyanobacteria and algae species can be found here. The green algae of the genera Crucigenia, Coelastrum, and Oocystis had the highest representation on the Kvítkovice pond. The cyanobacterial concentration was low. The Dehtář pond is dominated by filamentous cyanobacteria of the genera Anabaena and Pseudanabaena, which formed an algal bloom. Chlorococcales dominated the lower water column. In my work, I have not seen diurnal migration of any taxonomic group of algae and cyanobacteria. Microcystis, as a dominant species in the Kvítkovický pond, did not record vertical migration, indicating enough nutrients in these eutrophic ponds. Thus, phytoplankton is apparently not forced to migrate for nutrients to the bottom, and light is a limiting factor in their life cycle in summer.
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Floristicko-ekologická studie oblasti Bystřicka se zaměřením na ekologii zelených volvokálních řas
HNÁTEK, David
Since 1889 twenty-two different species of colonial algae from the order Volvocales have been found in the Czech Republic according to the available algological literature. In this work the morphology and ecology of these species is described in detail. Besides investigating the literature resources, I performed my own floristic research of twenty ponds near Bystřice u Benešova. Phytoplankton samples from these ponds were taken in spring, summer, and autumn of years 2014 and 2015 using phytoplankton net and at the same time the environmental characteristics such as pH, conductivity, water transparency, temperature, and degree of shading were measured. Cyanobacteria and algae in the samples were identified to the lowest possible taxonomic level and their relative abundance was assessed. The differences in species composition between ponds and between seasons were compared using basic statistical methods and relationship between environmental factors and species composition was studied.
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The development of physical, chemical and biological parameters of water in new constructed natural swimming pools.
VLKOVÁ, Dana
The goal of this work was to evaluate of water quality in natural swimming pools in Borovany and Sezimovo Ústí, to compare the differences in the results of water analyses in proper swimming water body and regenerative part, as well as to compare of both these localities. Most of results were gathered during 2016 in Borovany and during 2017 in Sezimovo Usti. Transparency, color of water, temperature, conductivity, concentration of dissolved O2, concentrations of NH4-N, NO2-N, NO3-N, TN, PO4-P, TP, Cl, turbidity, fluorescence, chlorophyll concentration, alkalinity, zooplankton and phytoplankton composition and bacterial contamination were monitored. The results confirmed the possibility to achieve the good water quality even though the problem with phosphorus removing remains. The comparison of both site showed more efficient functioning of regenerative zone in Borovany natural swimming pool.
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Fungal parasites as a factor affecting the dynamics of microalgal communities
Rosa, Jan ; Šťastný, Jan (advisor) ; Pichrtová, Martina (referee)
This bachelor thesis deals with fungal parasites which are an important factor that affects the dynamics of microalgal communities. Here I sum up the knowledge of parasites especially from Oomycota and Chytridiomycota along with a little focus on other groups. The basic characteristics of these fungal parasites, such as their host specificity and factors that affect their spreading ability between algal hosts, are summarized. The abiotic factors such as light and temperature, which are the most important factors causing epidemic, are mainly discussed. The fungal parasites can change the maximal population size and are able to alter the competitive relationships in microalgal communities. These factors are discussed in individual algal groups. The fungal parasites could be a negative economic player of the bioindustry and their future role in this industry is also discussed. Key words: parasite, host, host specificity, communities dynamics, algae, fungi, phytoplankton
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Zooplankton response to a change of water chemistry and amount of food during the recovery of lakes from acidification
Bartošíková, Martina ; Stuchlík, Evžen (advisor) ; Šorf, Michal (referee)
Anthropogenic acidification has affected assemblages in thousands of lakes in North America and Europe. It turned out that, during the acidification, the number of zooplankton changed and also the species composition of their assemblages, at some sites there was also the total disappearance. The main reason was a decrease of pH, wash out toxic aluminium and a change of trophic status. The rate and extent of biological recovery after restoring the pH in acidified lakes varies considerably across regions. Recovery of aquatic communities is significantly lagging behind the recovery in chemistry. Some zooplankton species are nonetheless able to quickly colonize recuperating ecosystems and in many acidified lakes again started to appear native species that have disappeared during acidification. The return of indigenous species, however, can be blocked acid-tolerant occurrence of species after species extinct occupied empty niches. Zooplankton can be affected by water chemistry directly, but also indirectly by the quality and quantity of food. An important factor is the possible spread of colonizing species. However, the relative roles of these factors in regulating recovery may be difficult to determine. Key words: zooplankton, acidification, water chemistry, aluminium toxicity, phytoplankton
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Phaeocystis - a key organism in dimethylsulfoniopropionate production; ecological and physiological functions of DMSP
Füllsacková, Alena ; Němcová, Yvonne (advisor) ; Pusztai, Martin (referee)
Dimethylsulfoniopropionate (DMSP) is an organic sulfur compound with an important ecological and physiological functions. DMSP is a major precursor for dimethylsulfid (DMS). DMSP is produced by variety of halophytic plants and phytoplankton for the purposes of osmotic regulation, antioxidation and protection from predators. It is especially widespread among the marine phytoplankton and it is ubiquitous in the euphotic zone. DMS and DMSP are also involved in flux of carbon and sulfur. Marine emissions of DMS have a particularly important role as precursors of atmospheric sulfur-containing aerosols that influence the Earth's climate system through direct backscatter of solar radiation and through cloud formation. DMSP is produced mainly by phytoplankton, because this group of organism is very large, I'll focus on Phaeocystis. Phaeocystis is a genus of marine phytoplankton with a worldwide distribution. It has a polymorphic life cycle alternating free-living cells and colonies but develops massive blooms under the colony form. Among the 10 species, only 3 (P. pouchetii, P. antarctica, P. globosa) have been reported as blooming species. DMSP is produced intracellulary and it is released as DMS. DMS concentration is high during the growth of the cells, predation or senescence. The production of DMSP is...
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