National Repository of Grey Literature 26 records found  1 - 10nextend  jump to record: Search took 0.00 seconds. 
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....
Long term dynamic of vegetation succession on post-mining sites.
Skalníková, Andrea ; Mudrák, Ondřej (advisor) ; Janíková, Eva (referee)
Spontaneous succession of vegetation can be one of the restoration approaches of disturbed sites after coal mining. It is therefore important to know the course of successional changes and whether it can be replicated. The spontaneous succession of vegetation on disturbed sites is usually based on monitoring of multiple sites of a different stage of succession. By their comparison the course of the succession over time is inferred. This approach of the study is called chronosequence (space-for-time substitution). Another option is to repeat monitoring of permanent plots, but it requires a long period of time to observe successional changes. Rarely are these approaches combined. In this thesis, I analyse the main trends in the succession of plant communities and their plants functional traits on five localities of various age during the 15 years. I have examined whether the localities follow similar successional trends. Data (plant coverage) were collected by annual resampling of 50 (ten per locality) permanent plots of 5 m x 5 m since 2007. By performing a multivariate CCA analysis, we analysed the species composition of the plant community, and by performing an RDA analysis, we analysed the changes in weighted averages of plant functional traits. In both cases, the localities and their...
Dynamic of the plant establishment in the experimental seeding into the grasslands restored on the former arable land
Šťástková, Eva ; Mudrák, Ondřej (advisor) ; Konečná, Marie (referee)
Grasslands of White Carpathians belong to the most diverse grasslands of the world, but despite this their large area was plowed in the past. During the last two decades one of the biggest ecological restoration projects in the Central Europe is there ongoing, which aims to restore arable fields back into species rich grasslands. As even a relatively species rich regional seed mixture cannot include the original grassland diversity, grasslands are dependent on spontaneous colonization species after initial sowing. Species, however, face the considerably altered environment, different to preserved reference grasslands. The question is, to what extent can be the colonization of grasslands successful. Eventually, if it is possible to sow them into species poor restored grassland and enforce the formation of a more diverse grassland community. This bachelor thesis experimentally compared establishment (number of individuals during the growing season 2021) of 10 grassland species in sowings on three restored grasslands (old 20 years since restoration) and on three reference grasslands, which were in their proximity and served as reference ecosystem. Sowing was conducted in autumn 2020 into the disturbed and undisturbed microsites 20 × 20 cm. All species successfully established at least in some number...
Modelling of spatiotemporal development of vegetation
Šálek, Vojtěch ; Frouz, Jan (advisor) ; Mudrák, Ondřej (referee)
Gathering quantitative data on stand density and aggregation of the most abundant woody species present during spontatneus succession on spoil heaps is a of the essence in situations, when we need to compare it with man-made sylviculture stands and other areas of of post-mining environment. For the scope of this study a large dataset, containing over 2500 trees on more then 11 hectares of spontaneous forest succession on spoil heaps. was measured and acquired. These entries were used to calculate indices of self-thinning, specifically Reineke's stand density index (SDI) and a index of clustering using Hopkins statistics (HSI). Data consists of stand measurements ranging from 16 to 90 years of continuous succession. Taking species composition into account, the study focuses mainly on population of silver birch, which reached dominant abundance on many of the studied areas and reference data on silver birch SDIs are common in literature. Along with stand density indices, the slopes of its functions were calculated and compared with the reference values. The correlations of clustering index values with site age, species composition, diameters at breast height, and density indices were analysed. Analysing the resulting values of stand-density indices for areas where birch was dominant, spontaneous...
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...
Performance of late succession tree species in reclaimed and unreclaimed post mining heaps
Šimáňová, Doubravka ; Frouz, Jan (advisor) ; Mudrák, Ondřej (referee)
As a result of surface mining, ecosystems are destroyed, soil deposited on landfills is subject to degradation, contamination and erosion events, the water regime of the area is changed and all vegetation is removed from the surface. The most common way of rehabilitating a destroyed ecosystem is forest restoration. This can be done either by technical reclamation, during which the surface is leveled, and selected trees are planted here, or it is possible to leave the area to natural development, which is called spontaneous succession. The thesis summarizes knowledge about both methods of restoration, including their advantages and disadvantages. In the practical part, the growth production of late successional species, Norway spruce (Picea abies) and European beech (Fagus sylvatica), growing on areas left for spontaneous development and on artificially reclaimed areas, on spoil heap near Sokolov, are compared. The results show that the trees in the stand of natural regeneration have better conditions for growth, but not all measured parameters are statistically supported. Therefore, this work can serve as a survey of potentially suitable parameters for the creation of a larger-scale study. Key words: spoil heaps, forest restoration, succession, technical reclamation
Intraspecific trait variability of plants in the succession on the Sokolov post-mining sites.
Říhová, Eva ; Mudrák, Ondřej (advisor) ; Lisner, Aleš (referee)
In primary succession, the colonization of plants is essential for the development of the ecosystem. Plants colonizing a disturbed site face a number of limiting factors, such as the adverse chemical and physical conditions of the substrate. In general, primary succession follows a trend of development from an unfavorable substrate to a substrate with available nutrients and water. Sokolov post-mining sites are an exception. Previous studies showed that in intermediate parts of the succession, plants should be the most limited by water, due to the formation of amorphous clay, which adhesively binds water. One of the ways how to determine the main limiting factors of plants and verify these assumptions is to study plant functional traits. The intraspecific shifts in functional traits during the succession may show how the plant environment changes for plants. In this thesis I have measured functional traits (plant height, specific leaf area, leaf area and leaf mass) of three species (Calamagrostis epigejos, Fragaria vesca, Tussilago farfara) at three spontaneously developing localities of Sokolov post-mining sites differing in age since heaping (2, 31, and 56 years). The intraspecific trait variability showed that the most limiting conditions for plant growth are at locality of intermediate age....
The effect of soil successional development in spoil heap on plant germination and growth
Pavlíčková, Hana ; Frouz, Jan (advisor) ; Mudrák, Ondřej (referee)
Previous field research show, that late successional species correspond with soil development, especially with organomineral A horizon developing. Aim of my thesis was to compare plant growth on different types of soil from spoil heaps. They were taken from three chronosequencies of different age - nonrecultivated and soils recultivated with planting of alder (Alnus) and spruce (Picea). In my research were used 7 types of plants - Arrhenatherum elatius, Centaureae jacea, Festuca rubra, Lychnis flos-cuculi, Lotus corniculatus, Plantago major, Trifolium medium. Spontaneous sites support more species than reclaimed ones this difference increase with plot age without distinct difference between early and late succession species. Key words Succession, recultivation, germination alder (Alnus), spruce (Picea), Arrhenatherum, Centaureae, Festuca, Lychnis, Lotus, Plantago, Trifolium.
Spontaneous succession and its role in vegetation recovery of post mining sites and other disturbed areas
Dobešová, Alena ; Frouz, Jan (advisor) ; Mudrák, Ondřej (referee)
Ecosystem restoration is vitally important, to return ecosystem in acceptable stage after anthropogenic disturbance. Spontaneous succession when disturbed area spontaneously recovers over time can be also considered as restoration method. This will restore vegetation cover, the interactions between biotic and abiotic components of the ecosystem, energy transfer, nutrient cycling and other important functions. In this thesis, I examined the influence of environmental variables on the cover of vegetation during succession. It was a mean annual temperature, mean annual precipitation, pH and soil types. The optimal course of succession appears to be a large increase of coverage at an early stage and its basically unchanged trend in other stages of succession. This was achived with an average annula temperature of 7řC, with an annual rainfall of 900 mm at pH 5 and the light and heavy soils. Key words: spontaneous succession, vegetation recovery, vegetation cover, disturbed areas
Current occurrence of eyebright (Euphrasia) in the Krkonoše (Giant) Mountains and the evaluation of the effect of the time of mowing
Blahník, Jan ; Krahulec, František (advisor) ; Mudrák, Ondřej (referee)
At the time the Black and Red List of the Vascular Plants of the Krkonoše (Giant) Mountains was being compiled it was found that no information was available about the distribution of eyebright (Euphrasia) or other facts concerning this hemiparasite growing in the Krkonoše. The aim of this work was to fill the gap. This was to be done by creating a GIS layer with the current distribution of eyebright in the mountains, by analysing the soils taken in places of eyebright occurrence, in neighbouring places and those closely resembling them but without eyebright. The soils were taken each time from five places in the particular locality and were analysed as a mixed sample. In all, 107 mixed soil samples were taken, of which 53 in places where eyebright occurred and in 54 similar places where eyebright was absent. Eyebright grows in places with a higher pH and it performs better in lower available phosphorus concentration. Management test was used to test the earlier time of mowing meadows containing eyebright, when a larger number of flowering eyebright occurs among the plants in comparison with the number of flowering eyebright on surfaces mown at a later time.; Management testing was carried out from June to July 2011 in six localities, with five plots in each locality, in the Eastern and Western...

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