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Substrate specifity of epiphytic communities of diatoms (Bacillariophyceae) and desmids (Desmidiales)
Mutinová, Petra ; Neustupa, Jiří (advisor) ; Šímová, Irena (referee)
Substrate specificity of epiphytic communities of diatoms (Bacillariophyceae) and desmids (Desmidiales) Bc. Petra Mutinová Master's thesis, Prague, 2015 Abstract It has been always assumed, and frequently reported, that host plants, as biologically active substrates, should have a direct influence on associated epiphyton. However, some studies favoured the neutral substrate hypothesis. Thus the relationship between host plant and epiphytic community remained unresolved. This Master's thesis focused on the basal question that numerous previous studies overlooked. Is there any significant influence of host plant on freshwater algal epiphyton in comparison to the influence of other factors, e.g. site and environmental conditions? In addition, substrate specificity of individual algal taxa was investigated. The research concerned several types of natural plant substrates at several water bodies in the Czech Republic, which provided a more accurate and general insight in the ecology of microphytobenthos. The results have demonstrated that site was the main factor affecting epiphytic community structure, followed by mild, but still noticeable, effect of environmental conditions (pH and conductivity). In contrary, host plant had almost no influence and very few algal species were found to be host specific....
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Composition and structure of larval trematode communities in model freshwater pulmonate gastropods in eutrophic environments in Central Europe
SOLDÁNOVÁ, Miroslava
This work applies advanced sampling (mark-release-recapture) and comparative approaches addressing the patterns in composition, structure and variability of larval trematode communities in three species of gastropod molluscs (Lymnaea stagnalis, Planorbarius corneus and Radix auricularia) at two nested scales of community organisation in typical Central European eutrophic environments. Hypothesis-testing with the application of null-model analyses, logistic regression modelling and multivariate randomisation techniques, revealed determinants of transmission rates, levels of infection and community structure in freshwater snail hosts in Central Europe and elucidated the mechanisms linking the spatial and temporal environmental variability with the action of complex community assembly rules in freshwater pulmonate snails.
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Soil nematodes in ungulate grazed and ungrazed forests of the Křivoklátsko Biosphere Reserve -- first results of an ongoing project
Háněl, Ladislav
The effect of ungulate grazing on various woodland ecosystems was studied in oak-hornbeam forest, subxerothermic oak forest, and herb-rich beech forest of the Křivoklátsko Biosphere Reserve. Samples of soil nematodes were taken in May 2006 from plots within enclosures established in 1993 and from plots outside the enclosures. The total abundance of nematodes varied from 248.7 to 790.0 x 10.sup.4./sup. ind.m.sup.-2./sup. and was always greater outside the enclosures. In two cases out of four the difference was statistically significant. Bacterivores were the most numerous nematodes. Their abundance was greater only in one plot outside the enclosure in the oak-hornbeam forest and about one half of the bacterivores were short-living .i.Rhabditis./i.. The abundance of root-fungal feeders (mainly .i.Filenchus./i.) was always greater outside the enclosures than within enclosures.
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Vliv různých travních směsí na společenstva pancířníků (Acari: Oribatida) v iniciálních sukcesních stádiích během obnovy květnatých luk
Starý, Josef
Altogether 400 quantitative soil samples were taken from 8 stationary plots in the localities Výzkum and Čertoryje in the Bílé Karpaty Mts. during the years 1999-2002. The present study is based on material of 10563 oribatid specimens belonging to 62 oribatid species. The lowest species richness and mean abundance were recorded on the plot with agricultural management.The highest mean abundance was found on the old sub-xerothermic meadow in Čertoryje. The eurytopic species .i.Scheloribates laevigatus./i. and .i.Tectocepheus velatus./i. as well as the heliophilous .i.Punctoribates punctum./i. were eudominant in all studied plots. These eudominant species were complemented by the dominant and recedent eurytopic species .i.Microppia minus, Hemileius initialis, Achipteria coleoptrata./i. and .i.Medioppia subpectimata./i.. The rare xerophilous species .i.Lucoppia burrowsi./i. was found in the plots sowed by different grass mixtures and in the fallow.
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Comparison of soil nematode communities in spruce forests of the Žofín woodland area (Novohradské hory Mts.) and the upper Vydra river basin (Šumava Mts.), Czech Republic
Háněl, Ladislav
Soil nematodes were studied in two spruce forests at the Žofín National Nature Reserve and in three spruce forests of the upper Vydra river basin, National Park Šumava, in South Bohemia. The total mean abundance of nematodes in the spruce forests ranged from 863 to 4877x10 3 ind.m-2 with variation from 231 to 6947x10 3 ind.m-2 on individual sampling dates. The most abundant nematode genera were root-fungal feeding Filenchus (48,3% of all nematode individuals in the spruce forests studied), bacterivorous Plectus (11,2%), and omnivorous Eudorylaimus (8,5%). The lowest abundance but the greatest variety of nematodes was found in a waterlogged spruce forests at the Žofín Reserve whereas the greatest abundance of nematodes occurred in the spruce forests of the Vydra river basin. The nematode fauna in the two regions compared showed particular differences, especially in the groups of bacterivorous, plant parasitic and predatory species.
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