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Development of resistant life stages and mechanisms of passive dispersal of freshwater copepods
Šliková, Adéla ; Juračka, Petr Jan (advisor) ; Fott, Jan (referee)
Copepods are an important part of metacommunities in freshwater and marine ecosystems. Freshwater copepods occur at all continents and are found in almost every water habitat. These small invertebrates cannot actively disperse among habitats and therefore have to rely on vectors of passive dispersal. Copepods can produce diapause life forms and are therefore able to survive unfavorable conditions during the transport. Throughout the ontogenetic development from an egg to adult stage, they have to pass naupliar and copepodit life stages. Various evolutionary lineages of copepods developed diapause phase at different life stage. Hence it is possible to observe both diapausing eggs as well as diapausing adults. Discussed vectors of passive dispersal are wind, floods, animal fur, animal gut, but also human recreational and industrial activity. This work summarizes basic knowledge about the mechanisms of development of copepods diapausing life stages and about their passive dispersal. Key words: passive dispersal, freshwater copepods, diapause
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Metacommunities of the copepods, molluscs and ostracods in Kokořínsko pools on the longterm gradient
Tichá, Adéla ; Juračka, Petr Jan (advisor) ; Šorfová, Vanda (referee)
Re-creation and building new small freshwater habitats belong among the important management activities within the Protected Landscape Area Kokořínsko - Máchův kraj (Czech Republic) for almost two decades. These pools keep the water within the landscape and serve as the habitats for vulnerable species of amphibians and invertebrates, which I have studied within this thesis. Most studies focusing on studying metacommunities of small water bodies have been based on the data from one or two seasons, and thus completely neglect the development of composition of these metacommunities over longer periods of time. This thesis builds on previous research on the species composition of small ponds in the Kokořínsko Protected Landscape Area, which had been done in 2005 and 2006. In 2009 and 2017, sampling in the same ponds continued. I investigated the influence of spatial and environmental variables of individual ponds on the species composition of ostracods, copepods and molluscs in specific years and how has the representation of individual species changed among those years. With one exception, I have not observed any new incoming species of copepods and ostracods since 2006; the number of species had in fact decreased. In the case of molluscs, there was a significant exchange of species between individual...
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Development of resistant life stages and mechanisms of passive dispersal of freshwater copepods
Šliková, Adéla ; Juračka, Petr Jan (advisor) ; Fott, Jan (referee)
Copepods are an important part of metacommunities in freshwater and marine ecosystems. Freshwater copepods occur at all continents and are found in almost every water habitat. These small invertebrates cannot actively disperse among habitats and therefore have to rely on vectors of passive dispersal. Copepods can produce diapause life forms and are therefore able to survive unfavorable conditions during the transport. Throughout the ontogenetic development from an egg to adult stage, they have to pass naupliar and copepodit life stages. Various evolutionary lineages of copepods developed diapause phase at different life stage. Hence it is possible to observe both diapausing eggs as well as diapausing adults. Discussed vectors of passive dispersal are wind, floods, animal fur, animal gut, but also human recreational and industrial activity. This work summarizes basic knowledge about the mechanisms of development of copepods diapausing life stages and about their passive dispersal. Key words: passive dispersal, freshwater copepods, diapause
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Passive dispersal of land snails (Gastropoda: Pulmonata) with focus on endodispersion via birds
Simonová, Jasna ; Juřičková, Lucie (advisor) ; Pech, Pavel (referee)
The ability of land snail active dispersal is very limited. Despite that, they have colonized even very isolated habitats and some species are able to disperse relatively fast on continental scale. This used to be explained by passive dispersal, especially via birds. Land snails could be transported on bird's body (ectodispersion) as well as inside their digestive tract (endodispersion), but the direct evidence of these processes has been more likely anecdotal. A review concerning passive dispersal of land snails via birds with focus on endodispersion is presented in this bachelor thesis. The methodological aspects of experimental studies, including relevant insights of other organism's endodispersion studies, are discussed. Selected traits of land snails and their avian vectors which can affect success of endodispersion are also discussed.
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