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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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Defence mechanisms of phytoplankton exposed to UV radiation
Dvořáková, Jana ; Němcová, Yvonne (advisor) ; Pichrtová, Martina (referee)
Phytoplankton builds an important part of energy flow in the Earth's ecosystem. It forms the basis of the food chain and represents main primary producers. The question arises, due to the continuing ozone depletion, what impact may cause the increasing intensity of UV radiation on aquatic ecosystems. Especially UV-B radiation is capable of penetrating depp into the water column and affects the key physiological processes (e.g. growth, reproduction) and causes acute physiological stress to aquatic organisms including phytoplankton. The gole of my thesis is to summarize the studies focused on the impact of UV radiation on planktonic algae and the defense mechanisms that reduce the negative effects of UV radiation. These mechanisms may be devided into three groups: active avoidance, production of UV-absorbing substances and repairs of damage induced by UV radiation. Powered by TCPDF (www.tcpdf.org)
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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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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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Photosynthetic characteristics of phytoplankton in eutrophic waters
Tesařová, Blanka ; Pechar, Libor (advisor) ; Fott, Jan (referee)
Photosynthesis and primary production were estimated in fishpond phytoplankton during period 2008-2010 in Třeboň fishpond region, Czech Republic. Photosynthesis was measured by the oxygen method in computer-assisted light pipetting system Illuminova. Altogether 64 samples of fishpond phytoplankton and 11 cyanobacterial cultures were analysed. Cyanobacteria and chlorococcal algae formed the most important part of phytoplankton biomass and their photosynthesis-irradiance (P-I) curves showed shade-adapted type of P-I curves with the high photosynthetic efficiency. No significant differences in the main parameters of P-I curves were obtained between different types of phytoplankton (chlorococcal-dominated, cyanobacteria- dominated). The results are consistent with the high turbid conditions in eutrophic or hypetrophic fishponds. On the contrary photosynthesis in cyanobacterial cultures differs from "wild" phytoplankton and therefore they can not be taken in primary production models. Primary production was estimated according Talling's model (1957), based on daily measurement of radiation, extinction coefficient of water and seasonal courses of chlorophyll concentration. Photosynthetic capacity and onset of light saturation determined in P-I curves were used as physiological parameters of Talling's model. The...
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Phytoplankton in experimental ponds: colonization and seasonal succession
Hrušková, Lenka ; Nedbalová, Linda (advisor) ; Lukavský, Jaromír (referee)
Artificial ponds are excellent for the study of phytoplankton ecology. They permit repeatable initial conditions and sufficient replication of independent experimental units in complex experiments to test hypotheses about the control of structure and function in natural communities. There were 20 experimental ponds constructed in Kokoř nsko Protected Landscape Area, from which samples were taken and analyzed. This study was part of the EU BIOPOOL. During the first two years after the filling of the ponds the colonization and the seasonal development of phytoplankton communities in the ponds were examined. The phytoplankton species composition was determined, then species richness and relative abundance of individual taxa were quantified. Species composition data were compared with the environmental parameters measured (temperature, oxygen concentration, pH, transparency, conductivity, depth, chlorophyll-a concentration, and zooplankton). In the spring 2007, the ponds were periodic, and followed a similar trend over time (February- April). There were dominated by the following taxonomic groups: Dinophyta, Chrysophyta, Cryptophyta, and Euglenophyta. After installing foil on the bottom of the ponds, the ponds were of permanent character. In terms of environmental parameters, the individual ponds...
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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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Plankton of small village ponds
ČEJNOVÁ, Monika
The object of my thesis was to document the basic characteristics of four small ponds. Register seasonal changes in the occurrence of selected zooplankton groups and compare individual ponds among them. Then evaluate management on ponds and assess the possible impact on the formation of plankton. These results were then compared with the current situation on standard economic ponds. In this study, I observed three private ponds and local pond, which were located in the cadastral area Lodhéřov. From the results it is evident, that the zooplankton development was in private ponds very slow, while at local pond was developed zooplankton quickly. The diversity of zooplankton species was higher in local pond. On private ponds showed a high increase in fish, which amounted to R1 597 kg/ha and R3 519 kg/ha. In terms of management of ponds R2 was the least effective because the gain was only 113 kg/ha. Private ponds, according to the average annual ration 2910 kg/ha still ranked in halfintesification, while local pond to intensification ration with 4557 kg/ha.
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Biology and ecology of invasive species bryozoan Pectinatella magnifica
SKUHROVEC, Tomáš
Biology and ecology of invasive species bryozoan Pectinatella magnifica The aim of this bachelor theses is to create a literary overview containing available information about biology and ecology of the species Pectinatella magnifica. This invasive bryozoan originates from North America. Its occurrence in the Czech Republic was first recorded in the 30s of the twentieth century around the rivers Labe and Vltava. However its first massive presence was reported in the year 2003 in the sand pit Cep in the national protected landscape area Třeboňsko. From the reservoir Cep, it spread into other locations (sand pits Cep I, Vlkov, Veselí, Veselí I., Horusice and into ponds Hejtman, Nový Kanclíř, Staňkovský and Podřezaný, where it found suitable conditions for its life. It can be found in other locations in the Czech Republic as well, but its occurrence does not reach such big amounts. Outside our country it can be found in other European states and in some Asian countries. Pectinatella magnifica is a colonial fresh water animal preferring asexual reproduction. The colonies have yellow and brown colour, a structure of a hard gelatine and a spherical or oblong shape. Pectinatella magnifica is an effective filter feeding invertebrate, its diet consists of phytoplankton, especially diatoms. The most significant ecological factor effecting its seasonal dynamics is the temperature, as it is a thermophilic species preferring the optimal temperature of 20°C. If the temperature sinks bellow 20°C, the colonies start to decline and the hibernating units, called statoblasts, are released. Pectinatella magnifica tends to occur in slightly alkaline fresh water with a lower conductivity (bellow 200 S.cm-1). Regarding the trophy, water, qualified from oligotrophic to mesotrophic, is suitable for Pectinatella magnifica. It is found especially on submerged branches and on driftwood in the areas of river banks. Within this species, the association with other water animals has been proved, for example with small crustaceans and snails. In the cavity of coelom, the sexual evolution of parasitic species Trichonosema and Tetracapsula has been proved, these species represent a group of significant parasites of salmonids. To be able to estimate and describe the influence of this species, recently spreading in biotopes, which it inhabits, it is necessary to get acquainted with its biology.
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