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Endozoochorous seed dispersal by free ranging herbivores
Lepková, Barbora
Endozoochorous dispersal of seeds is a very common phenomenon which may occur anywhere some animals feed on plants bearing mature seeds. Endozoochory has been identified as a potential driver for long-distance migration but there is a strong discrepancy between endozoochory by frugivorous animals and herbivores. Despite the fact that the latter has been observed as early as a century ago, our understanding of the herbivorous endozoochory is still limited, even more so when it comes to the free-ranging wild species of herbivores. Furthermore, the endozoochorous dispersal shows significant differences between study areas and between herbivore species suggesting we need information about the process from various study areas to draw any conclusions. This thesis aimed to: (i) research the species composition found in dung samples of wild boars and deer, (ii) quantify the effect of deer dung deposition on vegetation of dry grasslands, (iii) establish the adaptation of plant species to the passage through digestive tract, and (iv) disentangle the drivers of species composition dispersed in dung. The results of my research indicates: (i) the species composition in dung samples differs up to a point between deer and wild boars: some species are dispersed by both dispersers while other only by one of them....
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Endozoochorous seed dispersal by free ranging herbivores
Lepková, Barbora ; Herben, Tomáš (advisor) ; Eycott, Amy Elizabeth (referee) ; Mudrák, Ondřej (referee)
Endozoochorous dispersal of seeds is a very common phenomenon which may occur anywhere some animals feed on plants bearing mature seeds. Endozoochory has been identified as a potential driver for long-distance migration but there is a strong discrepancy between endozoochory by frugivorous animals and herbivores. Despite the fact that the latter has been observed as early as a century ago, our understanding of the herbivorous endozoochory is still limited, even more so when it comes to the free-ranging wild species of herbivores. Furthermore, the endozoochorous dispersal shows significant differences between study areas and between herbivore species suggesting we need information about the process from various study areas to draw any conclusions. This thesis aimed to: (i) research the species composition found in dung samples of wild boars and deer, (ii) quantify the effect of deer dung deposition on vegetation of dry grasslands, (iii) establish the adaptation of plant species to the passage through digestive tract, and (iv) disentangle the drivers of species composition dispersed in dung. The results of my research indicates: (i) the species composition in dung samples differs up to a point between deer and wild boars: some species are dispersed by both dispersers while other only by one of them....
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Dry grassland restoration on a limestone quarry landfill using different sowing densities
Strušková, Eliška ; Kuťáková, Eliška (advisor) ; Mudrák, Ondřej (referee)
Grassland restoration by sowing seeds of native species is one of the most commonly used methods of community restoration, especially in cases when conditions are not favourable for spontaneous succession, for example due to absence of a suitable seed source in the vicinity or introduction of unsuitable substrate. Although seeding is commonly used, there is still no consensus on what seeding densities are sufficient to restore the target community. The aim of this thesis is to assess the influence of seeding density on species composition of the restored xerotherm grassland on two different substrates in a limestone quarry in the Czech Karst during eight years from the beginning of the restoration. It also assesses the influence of the subsequent management of the site, specifically grazing. The results of this thesis show that the sowing density influences plant community composition and vegetation cover only in the first five to six years of the community development and only on the quarry substrate. On the ex-arable soil seeding density does not significantly affect the community composition. Plant community on this substrate is dominated by ruderal species. Grazing promotes vegetation development towards a community of dry grassland and suppresses non-target ruderal species. These findings can...
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Effect of grazing on bryophytes diversity of dry grasslands in the PLA Český kras
TENČÍK, Aleš
Dry grassland are among the most endangered plant communities mainly due to the overgrowth of a number of localities. That is why from the beginning of the 21st century pasture with mixed herds of sheep and goats is restored on the most valuable dry grassland sites in the Bohemian Karst as the way of maintaining these habitats. Concurrently, research sites each 1x1 m in size were set up at four pastured localities, and were paired with control sites equipped with a fence for the research of grazing effect on vegetation. The main aim of this work was to evaluate the effect of grazing on the diversity of bryophytes at the forty pairs of the above-mentioned areas in three types of calcareous dry grasslands. In addition to the inventory of bryophytes, data on the most important abiotic and biotic factors of the environment were recorded on individual sites. The total number of bryophyte species found at the research sites is 46. 37 species were found at the grazing areas and the same number was at the fenced areas. Minimal differences in the number of species of grazed and unspoilt areas were also found in the comparison of individual localities. The grazing effect was shown up more significantly on species richness in the comparison of individual types of communities, especially in broad-leaved dry grassland (T3.4). There was a 40% increase in the number of species on grazing areas. The environmental factors have a positive effect on the species abundance mainly due to the higher slope of the terrain and the correlation with the larger occurrence of the stones, the smaller coverage of the herb layer and the litter. These conditions prevailed in areas with rock outcrop vegetation with Festuca pallens (T3.1), where the largest species richness of bryophytes in area was found. In the obtained data, the influence of grazing on the species composition of bryophytes on grazed and unspoilt areas was also assessed with the statistical methods and the Sörensen test of beta-diversity. The results show that grazing significantly influences the species composition towards open grassland and supports the growth of the bryophytes T3.1 plant community at the expense of the T3.4 plant community
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The effect of landscape context on the restored meadows in the White Carpathians
ČERNÁ, Ivana
Methods suitable for restoration of dry grassland were reviewed. An index of isolation was calculated for each of 34 meadows in the White Carpathians, which were restored by sowing the regional seed mixtures in the course of the past ten years. The relationship between the isolation, the year of regrassing and the number of newly established target species by the spontaneous succesion was studied.
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