|
| |
|
|
Structure of zooplankton in reservoirs of the Jizera Mountains during the peaking anthropogenic acidification and recovery from acidification (1992-2011)
Bímová, Tereza ; Hořická, Zuzana (advisor) ; Seďa, Jaromír (referee)
Acidic atmospheric deposition and acidification of soil and water on the Earth's surface, due to emissions of sulfur and nitrogen into the atmosphere, have led to drastic changes in the composition of surface waters and their biota in many regions of the world over the last century. The number of species and biomass of phytoplankton, zooplankton and benthos were reduced, or some components (zooplankton, zoobenthos, fish) became extinct. In the Jizera Mountains (Northern Bohemia, Czech Republic), the man-made acidification has always been combined with a natural acidity (dystrophy) of waters, caused by a high amount of organic acids. Despite a strong recovery of water chemistry from acidification, that has started in the 1990s, biological recovery is delayed and much more complex. This master thesis is a study of the succession of zooplankton (crustaceans) in mountain reservoirs Souš, Bedřichov and Josefův Důl after decades of strong acidification. Biological recovery from acidification has been in progress differently in the drinking water reservoir Souš, which has long been limed, in the Bedřichov reservoir with naturally high content of organic material, and in the drinking water reservoir Josefův Důl, which is the largest and deepest one and which was most affected by acidification. Recovery of...
|
|
|
Diurnal vertical migrations of zooplankton in a stratified mountain reservoir
Adámek, Radek ; Hořická, Zuzana (advisor) ; Stuchlík, Evžen (referee)
The thesis - a literature review - was aimed at the phenomenon of diurnal vertical migration (DVM) of zooplankton, in relation to particular conditions in the Josefův Důl reservoir in the Jizera Mountains (northern Bohemia, Czech Republic). The area of the Jizera Mts has a very sensitive geology, and thus suffered a strong anthropogenic acidification in the second half of the 20th century. The consequence was a long-term degradation of chemistry and biology of soils and surface waters. The waters in the upper plateau of the mountains were fishless, with a low diversity and biomass of both the phytoplankton and zooplankton. Recovery from acidification is slowest in the deepest reservoir, Josefův Důl. Due to its morphology, thermal stratification, newly re-stocked brook charr population, and invertebrate predators' occurrence, the zooplankton distribution in the vertical profile is expected to be irregular, with DVM. The following diploma project, oriented to seasonal changes and vertical distribution of the zooplankton in the Josefův Důl reservoir, should contribute to long-term data on biological recovery of the reservoirs from acidification, and explain the role of biotic parameters in zooplankton succession.
|
|
|
Food quality impact on growth and survival of Daphnia longispina (Crustacea: Cladocera)
Sýkorová, Veronika ; Sacherová, Veronika (advisor) ; Macháček, Jiří (referee)
This thesis focuses on ecological processes among plankton organisms. It especially questions the influence of food quality on growth and survival of freshwater plankton. I focused on the influence of various ratios of nitrogen and phosphorus in available food. I am also interested in finding out the food requirements of chosen consumer Daphnia longispina. Within this broad topic, I specify a question, whether various quality and quantity of food influences the life history parameters of the species Daphnia longispina and whether the absence of common species of Cladoceran Daphnia longispina in Plešné Lake is caused by unsuitable quality of food. I have bred Daphnia longispina in laboratory conditions for two years. I fed it by algae Monoraphidium dybowskii isolated from Plešné Lake and grown in two media P-limited (C:P 1174), P-unlimited (C:P 290) and three concentration (1,2, 4 mg C/L). Cladocerans fed by food from medium that had a C:N:P ratio approximately the same as can be found in Plešné Lake (C:P 1174) lived for a singificantly shorter period of time and during the experiment they did not reproduce even in the case with the largest amount of food (4 mg C/L). This is a possible reason why Daphnia longispina did not return to Plešné Lake after the period of strong acidification, climax of...
|
|
|
Ověření možnosti dlouhodobě udržitelné akvakultury na Boheľovakých rybnících
ŠINDLER, Martin
The focus of the thesis was verifying the effects of fish breeding in production-oriented fish farming on the ecosystem of fish ponds. The observation was conducted in R1 and R3 Boheľov fish ponds in 2014 and 2016 seasons. The RKK and SGR parameters, the natural fish pond production and the overall production were monitored. The monitored chemical and physical parameters included the developments of the essential parameters at two-week intervals; oxygen, pH, transparency, temperature and insoluble substances. Chlorophyll-a, total phosphorus and total nitrogen were monitored to assess the timely trophy in the ponds. To assess the effects on water organism community zooplankton succession by Cladocera, Copepoda and Rotifera taxonomic orders was monitored at two-week intervals. The monitoring also included periodical checking of the biomass of undesired fish that reached the value of 44,5 kg.ha-1 in the R3 pond. Roach (Rutilus rutilus) was the dominating specie. Control fishing was carried out during the seasons to estimate the actual biomass of carp stock. The total production ranged between 922,1 - 1181,5 kg.ha-1. The RKK level was 2,73 - 3,26. The SGR value of 0,902 %.day-1 was reached in stock C1-2. High carp stock influenced the zooplankton communities. During the observation no occurrence of the intermediate zooplankton was found. The prevailing species of the Cladocera order included Bosmina longirostris, Dafnia galeata and D. parvula. In the Cladocera order there was prevalence of Acanthocyclops trajani and in rotifera order there was prevalence of Brachionus calycifloris, Asplanchna priodonta, Polyartha sp. Spearman's correlation confirmed difference between the total zooplankton in R1 pond compared with R3 pond in both seasons (R3 2014: rho=0,066; pval=0,854; R3 2016 rho=-0,018; pval=0,96). The TSI index showed hypertrophic condition in both ponds. The average values of the index were 78,3 (6,2) in R1 and 75,6 (?3,8) in R3. The lowest average oxygen values, namely 3,2 mg.l-1 (2,0), were in pond R3 in 2016. Taking account of the adverse development of the essential parameters (oxygen and clarity deficits) and the status of the trophy certain limitation of the farming intensity was proposed, namely: reducing the carp stock down to 1/3 including a calculation of the production-related financial loss. Reducing the stock is the only way how to make the fish ponds sustainable. Relevant compensation, in line with the effective European regulations, needs to be addressed hand in hand with the proposed measures.
|
|
|
The food of pikeperch (Sander lucioperca) fry in ponds with different kinds of management
URBÁNEK, Marek
The aim of this study was a comphensive assessment of the food of pikeperch fry in the monoculture rearing from the stage of summer fry to the stage of autumn fry in ponds with three different types of management and assessment of the influence of individual treatments for pikeperch production. The experiment was performed in small ponds in experimental facility of FFPW in Vodňany. The variants of pond treatment were: a) ponds with additional prey fish (fry of common carp (C. carpio) and grass carp (C. idella)), b) ponds with installed substrate from heather, c) control variant without any support of natural food of pikeperch. All treatments had four repetitions. Rearing of pikeperch fry lasted 97 days. In all treatments, the opportunistic food strategy of pikeperch fry was recorded during the whole period of rearing and the main recorded food was macrozoobenthos, especially insect larvae. Bigger species of zooplankton had also been often found in the stomachs of pikeperch. Considerable development of macrozoobenthos in all experimental ponds was probably caused by the presence of submerged macrophytes. Thus, this factor made harder to estimate influence of installed substrates from heather for production of pikeperch fry and composition of its food. In the treatment with prey fish, the total length (F (9. 450) = 91.1; p < 10-3) and weight (F (9. 450) = 61.9; p < 10-3) of pikeperch fry were for the whole period of rearing significantly higher in comparison to the other treatments. In addition, the survival of pikeperch in the treatment with prey fish reached to 56 - 92,4 % at the end of rearing. In the treatment with substrate from heather, the total length and weight of pikeperch was significantly higher in comparison to the control treatment only in the first term of sampling. In the rest of pikeperch fry rearing period were the values comparable or higher in control treatment. Thus, for the rearing of pikeperch from the stage of summer fry to the stage of autumn fry is appropriate to stock prey fish in ponds. In comparison to installation of artificial substrate, the diversity of water environment, which is subsequently able to provide sufficiently wide natural food for reared pikeperch, seems to be more decisive.
|
|
|
Fish farming in ponds exposed to municipal water management
CHMELICKÝ, Petr
In August 2014 a total die-off of fish stock occurred in Záhumenní velký, a pond with a surface area of 5.85 ha. The investigation of the fish kill revealed that the Jabkenice WWTP located above the pond area had discharged water of inappropriate quality (N-NH4+ -99.3 mg/l-1) into the pond. This event resulted in the monitoring of physical and chemical parameters of water quality, zooplankton sampling and measuring of growth dynamics of fish stock by using control reduction fishing. The survey conducted in 2015 studied three different ponds (Ohrada 0.85 ha, Záhumenní velký 5.85 ha and Vlkava 22.1 ha), located in the fertile lowland areas around Mladá Boleslav where pre-cleaned sewage water from the sewage treatment plants flows. The water samples taken both at the outflow of the waste water treatment plant and in the pond were analysed in an accredited laboratory. The following parameters were examined: BOD5, TN, CODCr, ammoniacal nitrogen, TP, nitrites, nitrates and others.
|
|
| |
|
|
Diet quality impact on growth and survival of freshwater zooplankton species
Sýkorová, Veronika ; Sacherová, Veronika (advisor) ; Nedbalová, Linda (referee)
Food quality has a significant influence on freshwater zooplankon. It influences its growth rate and development generally. By quality we understand a certain stoichiometric ratio of the main biogenic elements (carbon, nitrogen, phosphorus) in the biomass of food. Ecological stechiometry is helping to understand the balance of chemical elements in ecological interactions and processes. Freshwater zooplankton consists mostly of two groups of organisms: rotifers (Rotifera) and crustaceans (Crustacea) - cladocerans (Cladocera) and copepods (Copepoda). Each of this groups requires different quality of food. Most of filtering cladocerans are fast- growing organisms, which need a phosphorus-rich food for their fast development (small C:P ratio in food) and vice versa for most of the copepods. The food offered is not always ideal for all members of zooplankton, that is why various pre- and post- absorptional mechanisms developed to help them to cope with unsuitable food. The ability to survive unvafourable conditions is closely linked to the zoolpankton's reactions to unsuitable C:N:P ratio in its food. The C:N:P ratio in food of zooplankton also influences the species distribution in water bodies. Key words: stoichiometry, food quality, zooplankton
|
|
|
Comparing Study of Fluvial Lakes in Middle Part of Elbe River and Upper Parts of Lužnice and Svratka River
Havlíková, Petra ; Janský, Bohumír (advisor) ; Pithart, David (referee) ; Pokorný, Jan (referee)
COMPARATIVE STUDY OF FLUVIAL LAKES IN FLOODPLAINS OF THE ELBE, LUŽNICE AND SVRATKA RIVERS Petra Havlíková ABSTRACT The aim of the thesis was to specify key differences in chemistry and biota (zooplankton communities) among fluvial lakes in three regions of Czech Republic: "střední Polabí" (central part of the Elbe River on the territory of Bohemia), "Horní Lužnice" (the upper part of the Lužnice River on the territory of Bohemia), and the Svratka River near Milovy (upper part of the Svratka River). The 10 studied lakes of the three regions differ in size, geology, shading, the influence of the river, and the level of anthropogenic impact. The following hypotheses were tested: 1) The chemical composition of the water in fluvial lakes is significantly different in different areas (floodplains). In the central Elbe River floodplain, there are the highest values of conductivity and concentrations of organic matter and nutrients. Fluvial lakes of the Svratka River floodplain near Milovy show the lowest level of these parameters, and fluvial lakes of the upper Lužnice River occur between the two previous regions. 2) The chemistry of fluvial lakes that have contact with the river through surface connection is significantly influenced by the river, and differs from the chemistry in fluvial lakes without any direct...
|
guest ::
