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Chrysophycean cysts and scales in paleolimnological studies
Bartošová, Kateřina ; Němcová, Yvonne (advisor) ; Škaloudová, Magda (referee)
This thesis deals with chrysophyte scales and stomatocysts as useful tool of paleoecological reconstructions in lake ecosystems. In the first part the geological physical and biological aspects of lake reconstructions are described. The second part contents information about chrysophyte taxa and their utilisation as paleoekological indicators. Chrysophyte microphosils include two major groups of siliceous indicator: stomatocysts and sculptured and ornamented species-specific scales. Using surface-sediment training sets, quantitative inference models have been constructed for eutrophication, acidification, air-born pollution, salinification, climatic change, and other environmental changes. This thesis represents a literature review.
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Processes in the forest vegetation of thermophyticum in the past decades
Pospíšková, Marie ; Hédl, Radim (advisor) ; Szabó, Péter (referee)
The thermophilous forests, especially their herb layer, are important from the conservational as well as from the cultural point of view because they represent unique communities directly and indirectly affected by man on the long term basis. Since the 19th century the way these communities are affected changed significantly, the same way as the whole society changed, and the vegetation responded by shift of species composition, diversity and also changes of the spatial structure. This thesis brings together the most relevant changes of vegetation and their causes. However, there is similar situation in the whole Europe, or more widely in the whole temperate zone, thus there are references also for other countries. Regarding historical ecology, one of the most studied countries is the Great Britain, which is mentioned the most often in this work.
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Management of the protected areas in sand habitats
Šímová, Kamila ; Pivnička, Karel (referee) ; Münzbergová, Zuzana (advisor)
Management of the protected areas in sand habitats is a thesis interested in the management techniques in relation to the sand habitats. In Central Europe, sand habitats are a rare and threatened grassland biotope. In the Czech Republic, we can find natural sand habitats localities, which are threatened by the human impact and anthropogenic localities, which tend to increase in number. Diversity and richness of the natural stands is gradually decreasing due to the high sensitivity of the species to any change of the local environment. These changes are mainly caused by the human activity. The negative effects are eutrophication, acidification and accelerated succession. The management of the sand habitats should contain many succession regulation tools and techniques reducing eutrophication. I discuss mowing, removal of the expansive plant species, pasturage, burning and sod disturbance or sod cutting. Each of these methods has specific impacts on the ecosystems and the best management combines them to achieve the best performance of the protected area. The most preferable method seems to be sod cutting, due to its high effectivity. However, there are many questions about sod cutting that need to be answered in a future study, such as how the population dynamics after sod cutting will look like, what the...
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Dynamics of phosphates and nitrates in (Liderovice, Radimovice u Tábora, Košín and Jordán) water systems.
KURAL, Vladimír
This thesis deals with the evaluation of concentration levels of phosphates, nitrates and other parameters (pH, conductivity, suspended solids, alkalinity, total carbon, inorganic carbon, total organic carbon and total nitrogen) in fishpond systems at Tabor. Further was to consider the difference in value depending on the age of the systems and agricultural activities in their vicinity. Samples were taken in season 2015 Liderovické pond system (2 sampling points at the top of the system, one sampling point in the outflow from the system), Radimovická pond system (one sampling point at the top of the systém, one sampling point at the outlet of the system) and Jordan ( one sampling point at the outfall of the pond). The highest differences were found in the values of conductivity from 279 S.cm-1 to 1230 S.cm-1, the values of total carbon from 18.75 mg.l-1 to 67.33 mg.l-1, and the values of suspended solids from 1 mg.l-1 to 117.33 mg.l-1. The gradual increase in the value of NO3-N and PO4-P was registered during the season with Jordan. Based on the results we can say that the older (Radimovická system) showed higher levels of total carbon and younger (Liderovická system) showed higher NO3-N depending on land use in the surrounding area.
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Changes in physico-chemical parameters of the Orlik reservoir selected tributaries
ZELENKOVÁ, Kamila
The topic of the thesis is determination of concentration of dissolved solids in water and seasonal changes in surface water chemistry for specific affluents of Orlík water reservoir. Water samples were collected on regular basis and analysed in a laboratory during one season (November 2014 - November 2015). The thesis is focused on monitoring of changes in phosphate and nitrate concentrations, in particular. The results of analysis indicate that measured concentrations of substances at monitored locations reflect generally measured data within the region. Concentrations of NO3-N peak in winter to early spring seasons, therefore seasonal changes do occur; differences between locations have not been proven statistically. As for the parameter PO4-P within locations downstream pond systems no significant statistic differences were identified. Values of PO4-P concentration are not primarily associated with agricultural activities but rather with local sources existing within the catch basin. It has been concluded from testing water quality upstream and downstream fish ponds that pond management had no impact on quality of water within the monitored locations in 2015; respectively no additional phosphor and nitrogen load was imposed on Orlík water reservoir
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Management of agricultural landscape and its impact on ion concentrations in running water
MIKEŠOVÁ, Aneta
The aim of this thesis was to compare chemical and physical parameters of surface water drainage patterns in Novohradské mountains and identify the possible impact of agriculture on the values of these parameters. Were used data for 2015 and 2016. Sampling sites include agriculturally cultivated land, but also forest ecosystems. The work is mainly focused on the following parameters: conductivity, pH, alkalinity, NO3-N and PO4-P, which are parameters causing eutrophication of water. The difference between the upper closures flows in forest ecosystems and lower closures flows near the agriculturally cultivated land has been contradictory. Conductivity values clearly showed that agricultural activity deteriorating water quality because conductivity at lower closures flows was sometimes three times higher than conductivity in the forest ecosystems, but for example, the value of PO4-P concentrations were higher at the upper closures flows, ie in forest ecosystems.
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Impact of fish pond harvest on water quality especially on
FREIDINGER, Jan
The topic of this thesis is the impact of fish pond harvest on water quality especially on concentration of suspended solids and phosphorous. Goal of the study is to contribute to ongoing discussion about carp aquaculture's role in fresh water pollution. Sampling was carried out in five carp ponds in the Třeboňsko Protected Landscape Area. Main monitored parameters were concentration of suspended solids and total phosphorous during pond drainage and fish harvest.Results of the study confirmed very negative impact of fish harvest on water quality in recipient water.
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Respiration and oxygen deficit risk in eutrophic fishponds
LENDLEROVÁ, Lucie
The purpose of this thesis is to obtain informations about the parameters of environment, which increases respiratory processes in fishponds and can cause an oxygen deficit. 24 monitored lakes were chosen according to the requirements of Rybářství Třeboň a.s. Between 4. 2. 2014 and 30. 9. 2014 took place 10 samplings. Water samples were taken for chemical laboratory analysis. At the same time there were made field measurements of basic physico-chemical parameters - dissolved oxygen concentration, temperature, color and transparency. Laboratory analysis determined compound and forms of nitrogen, phosphorus, carbon and the quantity of chlorophyll-a. Plankton respiration per 24 hours was detected by measuring the oxygen consumption by plankton in sizes up to 235 microns. Relations between respiration and other parameters, and different concentration of dissolved oxygen at the surface and in the depth of 1 m and the other parameters were compared using regression and correlation analysis. The observed decreasing trend of the seasonal oxygen saturation indicates that whole fishpond is dominated by respiratory processes. The results of correlation analysis, comparing the relationship of environmental parameters and respiration pelagial per 24 hours, shows that respiration correlates most with organic carbon content (representing the amount of organic substance). Furthermore, positively correlates content of total nitrogen, the amount of phytoplankton expressed as chlorophyll-a concentration and transparency. Content of particulate and total nitrogen, amount of phytoplankton and transparency also positively correlated with respiration. Total phosphorus concentration correlates with the respiration least of the monitored parameters.
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The possibilities of water quality improvement in small catchments by landscape planning from the viewpoint of nutrients
VLK, Daniel
This bachelor thesisis is focused on the issue of increasing concentration of nutrients in the watershed, and subsequently in other natural ingredients, especially water . This thesis dealt with the most problematic nutrients that have affected the water quality such as nitrogen and phosphorus. Subsequently, there is cycle of both the above-mentioned substances described in detail. Particularly those elements get into the environment in excessive amount due to human activities. Therefore their natural cycles are distorted, and that can lead to natural habitats impairment.
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Determination of phosphorus sources and determine of corrective measures of Hornoveské eutrophic reservoir
Čech, Dalibor ; Palčík,, Jiří (referee) ; Biela, Renata (advisor)
The aim of the present master's thesis is to assess the problem of eutrophication in the reservoir named Hornoveská reservoir near the city of Fryšták. The main goal of this thesis is to do a search report on the topic of eutrophication of surface waters, to do practical measurement and make samples in the Hornoveská reservoir, and then evaluate results from these actions and determine the source of phosphorus in the reservoir. Last goal is to suggest actions which can improve the condition of reservoir by limitation the occurrence of algae and cyanobacteria in the summer period.
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