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Možnosti zlepšení kvality vody v chovu ryb pomocí plovoucích mokřadů - přehledová studie
JINDRA, Tomáš
The bachelor thesis deals with the technology of floating wetlands, which construction could lead to improvement of water quality in fishponds. The aim of the thesis is to describe existing methods of water purification using wetlands with surface and subsurface water flow (root treatment plants). Further, to describe the method of refining in biological treatment reservoirs. One of the main chapters describes the construction of an artificial floating wetland. The cost / function ratio is often emphasized in their construction. However, it is important to mention that not all materials have a positive effect on water quality such as artificial materials. If possible, natural biodegradable materials that are environmentally friendly and often easier to handle with should be preferred. In addition, they are able to decompose in the environment and this can also save the cost of their disposal. In the thesis, a list of suitable wetland plants is proposed, focusing on species that are capable of growth and survival in our climatic conditions. The choice of species also depends on the type of habitat. Due to the low water transparency in fishponds, emergent and floating plant species, such as common reed (Phragmites australis), reed canary grass (Phalaris arundinacea), cattail (Typha spp.), branched bur-reed (Sparganium erectum) and duckweed (Lemna spp.), could be suitable. Nowadays, fishponds are in unsustainable conditions and water quality may become a limiting factor in fish production in the future. Floating wetlands may play an important role in its improvement.
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Temporal changes in bird communities at the landscape level in Třeboň basin
Havelka, Jan ; Sedláček, Ondřej (advisor) ; Reif, Jiří (referee)
Population trends of birds are usually studied mainly on large national and continental scales or, on the contrary, quite locally. In an attempt to link these spatial scales, we repeated a quantitative survey of bird communities in the Třeboň Protected Area twenty years later (between 2001 and 2021). Bird counts were conducted during the breeding season on a fifty- kilometre transect (128 count points) intersecting a diverse range of habitats. We found declines in long-distance migrants and insectivorous birds compared to more stable or slightly increasing populations of resident species. Consistent with known trends, we also observed declines in populations of species tied to agricultural landscapes. Deviations from the well described trends by JPSP and PECBMS relate more to individual species characteristics. For example, we observed increases in populations of otherwise declining House Sparrow (Passer domesticus) and Field Sparrow (Passer montanus), or nationally stable Eurasian Siskin (Spinus spinus). Using detailed mapping of habitat and vegetation changes and other ecological characteristics of individual species, we have attempted to explain these general and site-specific changes in bird abundance and population trends. We were also interested in the manifestations of the generally...
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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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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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Příspěvek k poznání vegetace sinic a řas vodních biotopů na Nepomucku
HAZUKOVÁ, Václava
The algological research was conducted in the surroundings of Nepomuk. In total, 9 fishponds and 2 streams were investigated over two years. Samples of net phytoplankton, periphyton and phytobenthos were collected in spring, summer and autumn. Moreover, various environmental variables were measured at each sampling site. Specimens were identified to the lowest taxonomic level possible and the relative abundance was assessed. Seasonal fluctuations and changes in the species composition among sampling sites were compared and discussed. The influence of environmental variables on changes in planktic and benthic assemblies was analysed. The list of species and the photodocumentation are presented.
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Fishpond sediment – new approach to the nutrient recycling in the agricultural landscape
Potužák, Jan ; Duras, J. ; Kröpfelová, L. ; Šulcová, J. ; Chmelová, I. ; Benedová, Z. ; Svoboda, T. ; Novotný, O.
Possibilities of the use of the fishpond sediment in the improvement of arable land is discussed. Among others, this approach has a high potential to contribute to the recycling of phosphorus in the agriculture landscapes. For this purpose, we propose set of particular techniques which were tested in the field study.
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Fishponds and water quality
Duras, J. ; Potužák, Jan ; Marcel, M.
Most of the fishponds in the Czech Republic is highly eutrophic to hypertrophic. This situation is related to the run-off in the catchments and by the fis-farming management (especially fertilisation). Long-term monitoring of fishpond water quality is complicated by large spatiotemporal variability of the parameters measured.
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The chemistry of the fishpond water ČR - long term development of the chemistry of the fishpond water - effect of eutrophication
STRNADOVÁ, Johana
The thesis deals with eutrophication of fishponds in the sixteen regions in the Czech Republic. Data about basic chemistry and nutrients (nitrogen and phosphorus) were evaluated in terms of temporal (during the years 1995 - 2003 and 2012) and spatial differences. ANOVA one-way and linear regression analysis, were used for detail description. Only regions (locality) Lednice, Brno, Ostrava and Řežabinec showed regular differences in most of the parameters. Between other regions individual differences were frequently found, mostly in conductivity and alkalinity, which are primarily reflect the different character of the catchments e.g. natural conditions. Less significant differences were observed in total N, and minimal differences were found in total P and chlorophyll. The high level of fishpond eutrophication has been also demonstrated by similarities in seasonal trends. Increasing the average value of the total P from 0, 23 mg/L to 0, 32 mg/L and increased chlorophyll concentration from 76 ?g/L to 218 ?g/L from spring to summer, are typical patterns for shallow fishponds heavily loaded with nutrients. The results allow to conclude, that fishpond eutrophication level is similar over the most of studied regions and remains unchanged during the last decades.
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Spatial distribution of water bugs (Heteroptera: Nepomorpha) in fishponds: estimation and comparison based on results reached by classic method (netting) and method of light traps.
ČELOUDOVÁ, Monika
The aim of this methodically oriented thesis was to find spatial distribution of water bugs in fishpond by parallelly used two different sampling methods - classic method (netting) and light traps as well as to find, if sampling method can influence a result of ecological study by substantial way. Study was realized in the one locality - fishpond Polepšil (region: Vysočina: Moravskobudějovicko) in years 2007 and 2008. Spaces {--} transects for sampling were difined. Efficiency of water bug sampling by nett is conspicuously less than sampling by light traps. More species and individuals (in total sum of samples and in samples from individual transects too) were sampled by light traps under comparable conditions. Chemical yelow-green light of light traps was more attractive for water bugs than the pink one. Spatial preferences of some corixid species and their developmental stages were noted by application of light trap method of sampling. Light trap method of samplings brings more complete and valuable data for ecological studies of water bug communities.
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