|
|
Removal of different species of phytoplankton by dissolved air flotation
Sukopová, Martina ; Mega, Jaroslav (referee) ; Dolejš, Petr (advisor)
The work evaluates the efficiency of dissolved air flotation (DAF) in removal of various kinds of phytoplankton. As absolutely necessary in the process of water treatment proved the agglomeration phase, or coagulation and floculation. This phase neutralizes the particles so that they can fasten air bubbles. The efficiency of this process depends on several variables, though: the kind of coagulant used, dose, coagulation pH, duration of floculation and its intensity, recycle ratio and the polymer use in coagulation. The particle size volume distribution and the volume of organic matter in raw water also have certain influence on phytoplankton removal. Dissolved air flotation is currently the most suitable method of phytoplankton removal. It can remove 93-98 % of blue-green algae and even 99-99.9 % of algae. The efficiency of flotation was also compared to sedimentation for the economic reason. In the process of water treatment, the sedimentation is now being replaced by flotation.
|
|
|
Study of seasonal changes of water quality in Vír reservoir
Navrátilová, Martina ; Dolejš, Petr (referee) ; Chocholáčová, Hana (advisor)
Thesis deals with measuring of chosen indicators of water quality in Vír reservoir (temperature, pH, colour, turbidity, fluorescence of fykocyanin, concentration of chlorofyl-a, pheopigments, microcystin-LR, orthophosphates, nitrates, etc.). Samples were taken from the sampling profiles 10, 30 a 50 metres from absolute level and in the season from May to October was direct in reservoir measured a vertical profile by a multifunction sonde YSI 6600.
|
|
|
Study of the limnological components of the ecosytem of Lake Medard in 2022
Peterka, Jiří ; Hejzlar, Josef ; Nedoma, Jiří ; Znachor, Petr ; Seďa, Jaromír ; Vejřík, Lukáš
The report summarizes the results of research into the limnological and biological components of the ecosystem of the newly created Medard post-mining lake. The aim of the presented report is to summarize the results achieved for the year 2022 and recommendations for further monitoring. The year 2022 was the fifth year after the lake was completely filled, when water from the Ohře River was no longer added. Only small tributaries flowed into the lake from its own catchment area, and at the same time, water from the lake drained through seeps, which are apparently drained into the nearby rivers, the Ohře and the Svatava. The lake ecosystem reached the final state of its initial phase in terms of hydrological regime and nutrient load. This condition is characterized by very little water exchange and a low nutrient level with low productivity of plankton communities. There is the development of submerged macrovegetation in littoral zone and a specific seasonal change in chemistry and biological parameters. However, the aquatic ecosystem is still far from stabilized and the biological communities of the littoral zone (littoral) and open water (pelagial), including the fish community, still show significant interannual dynamics.
|
|
| |
|
|
Allelopathy of aquatic plants and its possible application to control cyanobacterial blooms
Kolářová, Anna ; Jandová, Kateřina (advisor) ; Kučerová, Andrea (referee)
The excessive growth of phytoplankton and the development of water bloom leading to the damage to aquatic ecosystems are becoming a more and more frequent problem. There are many methods to control the water bloom from which mainly those that use interactions of living organisms have been developing lately, with the utilisation of aquatic plant allelopathy being one of them. Allelopathy is a type of relationship between two organisms when one of them influences the other by secreting allelopathically active compounds in the environment. However, the effect of these secondary metabolites depends on many biotic and abiotic factors, which also has consequences for their potential use to control the water bloom. Although the results of many studies suggest that allelopathy can affect the community of phytoplankton, its role in aquatic ecosystems is still unclear. This thesis summarizes the knowledge about the occurrence of allelopathy among aquatic organisms, the modes of action of allelochemicals and the impacts of the key factors influencing the allelopathic effect. At the same time, it evaluates the prospects of using the allelopathy of aquatic plants to control water bloom and reviews experimental approaches to studying allelopathic interactions.
|
|
|
Influence of microplastics on aquatic organisms - an overview study
BÁRTOVÁ, Lucie
The aim of this bachelor thesis was to develop a review summarizing knowledge about the effect of microplastics on aquatic organisms. In recent years, negative impacts of microplastics on aquatic organisms have begun to be observed. This work clarifies the entry paths of microplastics to the water recipient and their occurrence in aquatic ecosystems. The effects of microplastics on aquatic organisms, both vertebrates and invertebrates and phytoplankton, were also presented. To work properly out this bachelor thesis, I have used Czech and foreign sources found in the scientist database. However, many studies are still needed to fully understand the impact of microplastics and deduce clear conclusions. In order to deduce general conclusions from the studies, it is necessary to standardize water sampling methods as well as methods for testing the effects on organisms.
|
|
|
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.
|
|
|
Sezónní dynamika bičíkatých řas v různých typech rybníků
STAŘÍKOVÁ, Ester
The research was conducted in the surroundings of Toužim town. Samples of plankton and metaphyton were collected from 10 fishponds over the year 2020, samples were taken in spring, summer, autumn, and winter. Various environmental variables were measured such as temperature, conductivity, pH, transparency, and nutrient content. The specimens were identified and relative abundance was assessed and later used for counting environmental indexes. The main focus was on flagellated algae and their seasonal changes in composition among other alga were compared. All the environmental data together with species data were statistically analyzed.
|
|
|
Photosynthetic activity of phytoplankton in eutrophic waters
TESAŘOVÁ, Blanka
Photosynthesis was measured in several natural populations and cultivated strains of cyanobacteria. In the natural fishpond phytoplankton species of the Microcystis genus and small {$\mu$}-cyanobakteria were dominated. Anabaena mendotae and Anabaena lemmermannii, different cultivated strains were selected for photosynthesis measurements. Photosynthesis was estimated as an oxygen evolution in Illuminova (Sweden AB) light pippeting system. During the experiment the oxygen concentration, temperature and photon flux density were detected automatically and registered in computer. Results were evaluated as Photosynthesis-Irradiance (P-I) response curves. Altogether 13 experiments were performed. In the natural cyanobacterial populations as well as in the cultivated strains the results confirmed high efficiency of photosynthesis in low irradiances. In some natural waterbloom-forming populations of Microcystis the results demonstrated also the high photosynthetic performace in high irradiances. It is evident that these cyanobacteria are able to avoid damage to the photosynthetic apparatus in photooxidative conditions. These findings probably reflect the mechanism by which cyanobacteria outcompete chlorococcal algae in the shallow eutrophic water bodies.
|
|
|
Niche width of eukaryotic marine phytoplankton with respect to recent and future climate change.
Junková, Natálie ; Kulichová, Jana (advisor) ; Neustupa, Jiří (referee)
This paper describes the concept of niche breadth of photoautotrophic protists and attempts to introduce us to the basic concepts we may encounter when studying the ecological niche. The review clarifies what a niche is and its components fundamental and realized niche and presents some examples of organisms that are specialists or generalists. It uses diatoms, dinoflagellates and Haptophytes to describe how they can be affected by climate change. Since the number of environmental changes is steadily increasing, it is very difficult to predict the changes in the coexistence of generalists and specialists. The thesis presents some of the main methods used in measuring the width of the ecological niche of protists, which can be MaxEnt, ONE and the most frequently mentioned OMI (outlying mean index) method, which is described in more detail in the thesis. Given the focus of the thesis on photoautotrophic marine plankton, the most frequently mentioned organisms are diatoms, dinoflagellates and Haptophyta. Finally, I summarize the main ocean factors that could be affected by climate change, which are mainly pH, temperature, salinity or the amount of available nutrients (carbon, nitrogen, phosphorus, silicon and iron).
|
guest ::
