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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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Horses and vegetation
Třeštíková, Tereza ; Herben, Tomáš (advisor) ; Mládek, Jan (referee)
Many studies show that large herbivores can have an important impact on the composition of vegetation. With the establishment of a year round, low density grazing regime, plant ecologists and nature managers expect that through selective grazing, herbivores will create a mosaic of different vegetation communities varying in structure and plant species composition. It is believed that such a mosaic in the end will guarantee a high degree of biodiversity. Grazing will, therefore, seem to be a suitable means to maintain grass. Also important is the ability of herbivores affect vegetation through endozoochory. In this thesis I have tried to find out what species of diet horses prefer regarding to plant species and what plant species they can spread through out endozoochory. I have compared this knowledge with the composition of pasture and meadow vegetation at the researched locality in Malenice and Hoslovice. With the purpose of finding out the preferences I established spots where I registered data on vegetation before pasture and the time intervals during the pasture. Afterwards, I researched the amount of sprouts and the composition of seedlings in excrements that I let germinate. I had to create phytocenologic shots from the pastures and meadows to compare the species of composition of grazed and...
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Free-ranging herbivores as a dispersal vector for species in abandoned landscape
Lepková, Barbora ; Vojta, Jaroslav (advisor) ; Karlík, Petr (referee)
Endozoochory is an important part of plant-animal relationship. In model area of the Doupov Mountains large herbivore mammals, such as red deer, sika deer and wild boar, act as effective seed dispersers. Out of 282 dung samples 29 719 seedlings of 91 species emerged. The most common species was Urtica dioica (80 % of all seedlings). The amount of seeds in dung as well as species composition were highly dependent on dispersing animal, both showed strong seasonality and differences between two studied localities. Frequency of species in dung did not correspond to their frequency in vegetation suggesting strong preferences of herbivores as predators. However more research is needed to test this hypothesis. Given very high time demands for samples processing beforehand the emergence experiment, the influence of concentration by washing through on seedling emergence and species composition was tested. According to preliminary results more seedlings and species emerge from concentrated samples. However, concentration has no effect on emergence of U. dioica as the most common species. Concentration of samples by running water is recommended for faster emergence in greenhouse conditions. Preliminary results also suggest that the approximation of number of seedlings/species on weight of dry mass is not...
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Methods for studying of free-living herbivores zoochory
Lepková, Barbora ; Vojta, Jaroslav (advisor) ; Pokorná, Adéla (referee)
Epizoochory as well as endozoochory are well known dispersal mechanisms. This topic is being studied more and more often lately but our knowledge is still incomplete. The traits of plants dispersed this way are not yet well investigated and there is a gap in knowledge of mutual interaction between plant and animal species during transport. The impact of transport itself especially in endozooochory is also poorly known. We study endozoochory most often using seedling emergence method for seeds contained in dung. Feeding experiments are an interesting way of research and we use them to learn the survival rates of seeds in digestive tract. The most favourite methods for research of epizoochory are tamed animals and all types of dummies. Various laboratory experiments, for example shaking machine, are also frequently used.
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Physical dormancy of seeds
Jiroušková, Anna ; Ponert, Jan (advisor) ; Vosolsobě, Stanislav (referee)
Physical dormancy of seeds is a widespread adaptation, allowing plant seeds to time the germination to a suitable season. Seeds with physical dormancy possess hard seed coats, which are impermeable to water and sometimes also to gases. This allows seeds to create a long-term seed bank and to wait for favourable conditions even for years. There are two main mechanisms, which break physical dormancy and enable water to enter the seed. The seed coat can be disrupted through the whole surface, or in one specialized place only. The disruption through the whole surface is common in the seeds dispersed by endozoochory. In this case, the long-distance seed dispersal brings an important advantage. In physically dormant seeds, which are dispersed by other ways, a complicated structure called water gap is usually present in the seed coat. Water gap responds to exogenous signals and controls when the water enters the seed. In such a case, physical dormancy can be broken as a response to annual or diurnal temperature fluctuations, which times germination into a proper time of the year. Another species germinate in response to high temperatures during a fire. This ensures, that seedlings emerge in suitable conditions with a high level of available nutrients, low competition and that they can restore the damaged...
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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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Free-ranging herbivores as a dispersal vector for species in abandoned landscape
Lepková, Barbora ; Vojta, Jaroslav (advisor) ; Karlík, Petr (referee)
Endozoochory is an important part of plant-animal relationship. In model area of the Doupov Mountains large herbivore mammals, such as red deer, sika deer and wild boar, act as effective seed dispersers. Out of 282 dung samples 29 719 seedlings of 91 species emerged. The most common species was Urtica dioica (80 % of all seedlings). The amount of seeds in dung as well as species composition were highly dependent on dispersing animal, both showed strong seasonality and differences between two studied localities. Frequency of species in dung did not correspond to their frequency in vegetation suggesting strong preferences of herbivores as predators. However more research is needed to test this hypothesis. Given very high time demands for samples processing beforehand the emergence experiment, the influence of concentration by washing through on seedling emergence and species composition was tested. According to preliminary results more seedlings and species emerge from concentrated samples. However, concentration has no effect on emergence of U. dioica as the most common species. Concentration of samples by running water is recommended for faster emergence in greenhouse conditions. Preliminary results also suggest that the approximation of number of seedlings/species on weight of dry mass is not...
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Horses and vegetation
Třeštíková, Tereza ; Herben, Tomáš (advisor) ; Mládek, Jan (referee)
Many studies show that large herbivores can have an important impact on the composition of vegetation. With the establishment of a year round, low density grazing regime, plant ecologists and nature managers expect that through selective grazing, herbivores will create a mosaic of different vegetation communities varying in structure and plant species composition. It is believed that such a mosaic in the end will guarantee a high degree of biodiversity. Grazing will, therefore, seem to be a suitable means to maintain grass. Also important is the ability of herbivores affect vegetation through endozoochory. In this thesis I have tried to find out what species of diet horses prefer regarding to plant species and what plant species they can spread through out endozoochory. I have compared this knowledge with the composition of pasture and meadow vegetation at the researched locality in Malenice and Hoslovice. With the purpose of finding out the preferences I established spots where I registered data on vegetation before pasture and the time intervals during the pasture. Afterwards, I researched the amount of sprouts and the composition of seedlings in excrements that I let germinate. I had to create phytocenologic shots from the pastures and meadows to compare the species of composition of grazed and...
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Methods for studying of free-living herbivores zoochory
Lepková, Barbora ; Vojta, Jaroslav (advisor) ; Pokorná, Adéla (referee)
Epizoochory as well as endozoochory are well known dispersal mechanisms. This topic is being studied more and more often lately but our knowledge is still incomplete. The traits of plants dispersed this way are not yet well investigated and there is a gap in knowledge of mutual interaction between plant and animal species during transport. The impact of transport itself especially in endozooochory is also poorly known. We study endozoochory most often using seedling emergence method for seeds contained in dung. Feeding experiments are an interesting way of research and we use them to learn the survival rates of seeds in digestive tract. The most favourite methods for research of epizoochory are tamed animals and all types of dummies. Various laboratory experiments, for example shaking machine, are also frequently used.
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