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Ponds and lakes of South Moravia ceased to exist
Vaštík, Karel ; Doležal, Petr (referee) ; Králová, Helena (advisor)
This bachelor work deals with the research of extinct water bodies of South Moravia from the oldest mapped history till today. It analyzes their origin, development during the time and their extinct, and the gained findings illustrates on selected water bodies. It analyses also the restoration possibilities of selected lakes and ponds.
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The Revitalization of Mixed Use Zone Rybníky in Zlín
Hudečková, Petra ; Kotásek, Jiří (referee) ; Zemánková, Helena (advisor)
The main idea of the project is a gradual interpenetration of a town and nature and concurrently the free connection of the new projected area Rybníky and neighbouring quarter Prštné. And so the density of housing gradually becomes thinner and the density of vegetation thicker from the South to the North. At the same moment the form and function of buildings are changing. There is a sport area in greenery between Rybníky and Prštné as an open connection of new buildings in Rybníky and old ones in Prštné. Entrances of the area are defined by two dominant administration buildings. A local centre of the area is a park with a pavilion in its heart and a near public courtyard with café, kindergarten and the home for the elderly and singles. The projected area is full of cycle paths which connect the quarter and the Zlín city centre. The riverbank with a relaxation zone is created along the river Dřevnice.
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Floristicko-ekologická studie sinic a řas v různých typech stojatých vod na severním Plzeňsku
ČECHUROVÁ, Markéta
The algological research was realized on 10 various water bodies in the northern Pilsen region during the year 2020. They were mainly post-mining sites or artificial ponds, where plankton samples were collected. Environmental characteristics (pH, conductivity, water transparency, temperature, amount of nutrients) were measured. Cyanobacteria and algae found in samples were identified to the possible lowest taxonomic level, also relative abundance levels were stated. The relationship between environment and the species composition was studied. A total of 77 phytoplankton species were recorded.
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Rozvoj zooplanktonu v rybnících s produkcí rychlených stádií hospodářsky významných druhů ryb
PECHA, Oldřich
This master thesis was focused on zooplankton development in ponds with advanced fry rearing of economically important fish species. For the purpose of my study, we sampled pond cascade that is managed by Štičí líheň - ESOX, spol. s r.o. in the village Liderovice, near Tábor. In this particular pond cascade, the annual production of advanced fry of economically important fish species takes place, namely pike, pikeperch, carp, tench and grass carp. Importantly, pond cascade is used several times during one growing season, and zooplankton is the main food source of all early stages of rared fish. For the production of advanced fry of fish served 3 ponds, which were released and refilled 2-3 times a season. Fourth pond served as a control stocked with one year old carp throughout the whole season. The water from an upper pond in the cascade served as zooplankton inoculum to a lower pond after the pond harvesting. Statistical analyses showed that the fry of different fish species in ponds lying in the same cascade does not affect the composition of zooplankton after restocking and water refilling. The only difference we noticed was in the treatment with pikeperch, which partially does not share the food base of other monitored species.We also found out, that the occurrence of Cyclops vicinus, Daphnia magna, D. ambigua or D. pulicaria was positively correlated with increased P-PO4 concentrations. We also confirmed that pond ecosystem can effectively retain nutrients from basins and use them for its production. As was shown after a short rain when the measured concentration of total phosphorus in the inflow in our pond system was 0.50 mg/L, on the contrary in the last pond of our cascade we measured values below 0.08 mg/L. High transparency was maintained in the whole cascade throughout the monitoring period, and an adequate economic profit was generated. Such management can be applied to only a few ponds (systems).
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Potravní zdroje plůdku reofilních ryb v rybnících s instalovanými světelnými a barevnými atraktanty hmyzu
KAJGROVÁ, Lenka
The aim of this work was to evaluate the food base (zooplankton, zoobenthos and aerial insects) and production results in culture of two-year-old golden ide (Leuciscus idus aber. orfus) and chub (Squalius cephalus). The specifics of the study were to use the attractants (yellow plates) and submersed lights as a supplement to the nutrition of farmed fish. Experimental rearing took place in the earth ponds in the area of Experimental Fish Culture Facility in Vodňany (Czechia) and in the storage ponds in Schlossfischerei Schönau bei Litschau (Austria). Zooplankton composition and physico-chemical parameters were monitored during regular two-week sampling periods. Monitoring of zoobenthos and terrestrial insects captured by attractants was performed at monthly intervals. Macrozoobenthos was sampled by Ekman Grab. After processing the samples in the laboratory, the benthic invertebrates were divided into three groups - Chironomidae, Oligochaeta and Varia. Zooplankton was collected by planktonic mesh in the 3 m long hauling and divided into the fraction of small zooplankton (Daphnidae < 499 micrometre, Copepoda < 999 and > 1000 micrometre and Others - small Cladocera), and into the fraction of coarse zooplankton (Daphnidae 500 - 999, Daphnidae 1000 - 1499 and > 1500 micrometre). Terrestrial insects were captured by installed attractants for a specified time period of day (colour attractants) or night (light attractants). The results show that the environmental conditions of the monitored ponds did not differ significantly. Abundance of coarse zooplankton in both experimental cultures was influenced by fish. The density of zoobenthos did not differ significantly. However, the values in the ponds with the lights were higher than in the control. According to the analysis of growth and production data, the installation of insect attractants as a supplementary measure to fish nutrition in aquaculture seems to be beneficial for production results. The average weight of golden ide increased during the growing season from the initial 4,3 g to 26,9 +- 4,9; 32,3 +- 6,5 and 41,2 +- 9,2 g in control ponds, ponds using lights and yellow plates, respectively. The differences between both control and experimental treatments as well as between lights and yellow plates were highly significant (p < 0,001). In the culture of chub using light attractants, the average fish weight increased from the initial 12,7 g to 41,9 +- 2,2 g, respectively to 26,7 +- 5,5 g in control. In both treatments, the production was analogously higher.
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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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Dynamika rybničního ekosystému z hlediska produckční ekologie
RUTEGWA, Marcellin
With the rise of environmental concerns, fish farmers are facing the challenge of maximizing fish production while maintaining the ecosystem integrity of fishponds. In semi-intensive ponds, fish production is based on the utilisation of the natural production potential of the pond ecosystem and supplementary feed. Understanding the sources and the fate of inputs in fishponds is crucial to assess the utilisation efficiency of these inputs and hence reduce nutrients and organic matter losses. Ecological integrity of ponds is not regularly assessed in the Czech Republic, where pond aquaculture is an important economic activity. Therefore, the quality of inflow, pond water and effluent were monitored in the Dehtář pond from 2014 to 2018. Nutrient and organic carbon budgets were used to quantify the sources and fates of nutrients and organic matter inputs in Dehtář. Assessment of ecosystem metabolic rates, plankton community composition, utilisation efficiency of nutrient and organic carbon inputs and nutrient retention were used to indicate the effect of fishery practices on the structure and functioning of the pond ecosystem. The transboundary layer model was used to determine and compare the levels of dissolved and diffusive methane (CH4) from two types of fishponds (main and nursery) differing in individual fish size of cultured common carp. The results showed that the Dehtář pond became hypereutrophic due to fishery management, namely high fish stock, associated weed fish, manuring and supplementary feeding. The phytoplankton assemblage was dominated by eutrophication tolerant species, including toxic cyanobacteria. Larger sized zooplankton disappeared from the pond due to the high grazing pressure of fish stock already in the spring. The major sources of phosphorus, nitrogen and organic carbon inputs to the pond were feed, water inflow and primary production, respectively. Accumulation in water and sediments were the main fate of nitrogen and phosphorus whereas respiration was the main fate of organic carbon. The utilisation efficiency of nutrient inputs was comparable to results from other studies but the utilisation efficiency of organic carbon inputs was rather lower. In general, this efficiency was low due to the poor quality and low digestibility of cereals used as fish feed and the inability to transfer the primary production to fish. The potential of the Dehtář pond to retain nutrients is comparable with other temperate lakes and reservoirs. This may be explained by a high load of nutrients, their assimilation by fish and phytoplankton, sedimentation and denitrification. However, during the fish harvest, part of the retained nutrients is released and discharged. Furthermore, it was found that unused organic matter partly fuels the production of methane, which is then released into the atmosphere. The methane concentration was higher in nursery ponds than in main ponds, but the diffusive methane emission did not differ much between the two types of ponds. Based on our present findings we highly recommend to conduct more research activities heading to more sustainable pond management practices that can maximize fish production while minimizing pollution risks in the fishponds and their catchments.
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