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Food composition and feeding selectivity of zooplankton
Lis, Jonáš ; Škaloud, Pavel (advisor) ; Čablová, Radka (referee)
Zooplankton are an important link in the food web between phytoplankton and higher tro- phic levels, and understanding their feeding preferences is the key to unraveling the functions and dynamics of aquatic ecosystems. Current knowledge of zooplankton food composition is limited, consisting mainly of laboratory experiments that have revealed different hunting strategies and selection of prey based on size and nutritional value. Recently, publications have emerged that, through the use of DNA metabarcoding, provide a completely new and comprehensive insight into the diversity of zooplankton diet composition, especially copepods, cladocerans and rotifers. These methods reveal that the feeding niches of copepods and cladocerans are distinct and do not overlap. In general, both groups are said to prefer mainly diatoms as their food, when available. The food niches of rotifers are so diverse that no clear trend can be established for the entire phylum. Cyanobacteria appear to be the main source of energy for zooplankton and are proba- bly consumed by metazooplankton largely as secondary prey when consuming ciliates and other heterotrophic prey. Furthermore, differences in feeding niches between species are known and can be partly explained by their vertical distribution, and different levels of feeding...
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Společenstva korýšů a vířníků v přirozených a revitalizovaných rašeliništích
Pfeifer, Lukáš
The theoretical part of the diploma thesis evaluates the current state of peatlands in the Czech Republic. Peatland were affected by drainage and the subsequent drying due to the peat extraction. There is the effort to restore these localities to their natural character and to protect them at present. The practical part evaluates species composition of mi-crocrustaceans and rotifers of monitored natural and restored peatlands in the Ore Mountains and Šumava. A total of 39 taxa of rotifers and planktonic crustaceans was found. The impact of restoration on these communities was evaluated based on differ-ences in species composition.
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Phenotypic plasticity of planktonic rotifers as a response to predator.
VAJDIAKOVÁ, Nikola
The aim of this thesis is to assemble essential information about phenotypic plasticity of zooplankton, especially planktonic rotifers. More specifically, the thesis is focused on predatorinduced morphological changes. I introduced different types of predators and their behavioral, physiological and morphological impacts on zooplankton. Moreover, I examined the effects of inducible morphological defences on the planctic rotifers.
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The community of zooplankton in the pools in inundation area of Lužnice river
ŠEBESTA, Roman
This thesis aims to discuss generally the pools of river with a focus on the Upper Lužnice river maiinly on zooplankton communities, which ooccurs in these locations. Regular sampling of communities in different types of river pools better then identify their species and numerous changes during the year. Thesis deal with samplinng techniques and laboratory processing sampples of the zooplankton to.
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The role of rotifers by filtration of \kur{Cryptosporidium} in water column
BRŮČKOVÁ, Petra
Filtration abilities of Cryptosporidium parvum oocysts by rotifers (Brachionus calyciflorus) were studied. The filtration rate of rotifers is quick: the passage of oocysts through the digestive system is few minutes only. During the first 10 minutes 24300 of whole amount one million oocysts passed through the digestive system of 100 rotifers. Moreover, 93% of oocysts were death after passage. All oocysts expelled were unable to infect suckling BALB/c mice. Oocysts were degraded in mastax, stomach and intestine. Rotifers can be use for detection of cryptosporidia oocysts in water and they effectively decrease their numbers.
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