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Seasonal and long-term dynamic of plankton communities of small water-bodies
Pejsar, Patrik ; Černý, Martin (advisor) ; Juračka, Petr Jan (referee)
Zooplankton pool-inhabiting organisms form metacommunities and metapopulations. Locations are connected through dispersion which is an essential part of colonization-extinction dynamic. Locations vary with the environmental conditions, the specifics of the community and the biotic interactions taking place there. Differences in these parameters may occur between spatially separated pools or in one pool throughout time. These changes are caused by seasonal dynamics, disturbances, long-term development of environmental conditions or biotic factors such as predation, competition and parasite influence. On a long-term scale the locations are classified into rather stable and ephemeral. In pool environment the ephemeral locations may unexpectedly be the driving force of metacommunity and metapopulation processes according to the "inverse mainland-island" theory. Global climate change has an essential influence on zooplankton dynamic in smaller water-bodies. Hydrology of pools and through it also life dynamics of plankton organisms is directly influenced by temperature changes and precipitation. Regional metacommunity and metapopulation dynamics are changing in dependency on regional course of climate change and the specifics of these water-bodies and the communities living there.
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Freshwater fishless pools: from the metacommunties to the systematics
Juračka, Petr Jan ; Petrusek, Adam (advisor) ; Kotov, Alexey (referee) ; Zhai, Marie (referee)
Freshwater fishless pools: from the metacommunities to the systematics Petr Jan Juračka, Ph.D. Thesis, 2016-04-08 ABSTRACT Despite their small size, freshwater fishless pools often contain complex communities and substantially increase regional invertebrate and macrophyte biodiversity. The main core of this thesis originates from such habitats, which were newly created for the conservation purposes in the Protected Landscape Area Kokořínsko, Czech Republic. This landscape consists of deep valleys separated by steep sandstone ridges and is characteristic for very sparse stream network and low number of large water habitats, which consequents in generally low abundance of waterfowl. We studied microcrustacean metacommunities of 42 selected pools scattered over the area of approximately 220 km2 . Using variation partitioning of the species composition, analyses of the species richness and colonization experiment in the study area, we identified that spatial distribution of the habitats and number of neighbouring aquatic habitats play a major role in assembly of local communities. This led us to the conclusion that the landscape heterogeneity served as a partial barrier to dispersal of microcrustaceans. Subsequently, we compared this pattern of the microcrustacean metacommunity with other invertebrates of...
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