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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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Modelling of land cover change in abandoned landscape using time series of aerial photography
Brůna, Josef ; Vojta, Jaroslav (advisor) ; Jačková, Kateřina (referee)
Obsah 5 English abstract This thesis deals with modelling of land cover change in abandoned landscape. The study site is located in the military area Hradiště, around the former village Tocov, it is 2,5 km long and 2 km wide. Due to lack of historical vegetation data on landscape scale, historical aerial photographs were used as a primary source of data. They were orthorectified, mosaicked and automatically object oriented then classified in two categories woodland and grassland. Changes between two successive classified images were modelled with generalized linear models with mixed effects (lmer). Variables that were derived from digital elevation model, former land use and spatial variables computed with algorithms based on cellular automata were used. In order to verify the model predictions with the actual situation and for easier interpretation and visualization of results, a new application PEMZOK (Spatially explicit model of overgrowth of abandoned landscape) was developed and is one of the results of this work. Rapid rate of overgrowth of remaining grasslands was found. The largest observed effect on the spread of trees had the distance to the nearest tree or shrub and density of trees in the vicinity (15 m × 15 m) and the wider neighbourhood (105 m × 105 m). Models with these variables and land use...
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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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Fytocenological survey of the wetland in Řevnice and proposal for its revitalization
Szücsová, Veronika ; Čihař, Martin (advisor) ; Vojta, Jaroslav (referee)
This study deals with the main environmental factor that can influence river bank vegetation on the site V Túních in Central bohemia, near Berounka river. This is the rest of the old river arm of the river Berounka which is adjacent to the soft meadow willow, poplar and meadow communities. The site is now heavily influenced by human activities and the pool is becoming degraded, part of the work is to propose measures for their protection Phytosociological survey and mapping of plant communities was carried, . The pH, conductivity, water level, moisture and organic matter in soil were measured. Effect of these enviornmental parameters on vegeration composition was explored using CCA. Tracking the historical development of plant cover using orotofotomap from 1950, 1976, 1985, 1994 and 2008 show komplete removal of woody vegetating in 50s and their regeneration. The proposed management is recommended to remove or reduce the incidence of invasive plants and invasive species, restore the hydrological regime of the artificial deepening of the pool.
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Spoil heap heterogenity and its effect on vegetation
Pochmanová, Pavla ; Frouz, Jan (advisor) ; Vojta, Jaroslav (referee)
One of the major industrial activities in North West Bohemia is brown coal mining. Mines and heaps originated during the mining process represent main elements of adverse changes in the local landscape. They are causes of changes of all subsystems of landscape, soil and mineral environment, water situation, atmosphere, etc. Subsequent recovering of these impacts of mining activities is not easy in terms of technology or time. Reclamation engages in such activities. Its aim is to restore production function of land and to create a balanced, aesthetically, naturally and hygienically valuable landscape. This thesis deals with the development of mining and descriptions of various methods of reclamation with regard to the heterogeneity of reclaimed areas. In conclusion, own experiments carried on the surface of succession area "Radovesice XVII.B" are presented. Key words: succession, land reclamation, heaps tailings, mining activity and heterogenity
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Historical and present anthropogenic gradients in landscape
Staněk, Ondřej ; Vojta, Jaroslav (advisor) ; Klinerová, Tereza (referee)
My bachelor thesis is concerned in determining and classification of main anthropogenic influences in various ecosystems. Intensity and direction of landscape transformations such as nutrient income, terrain changes, disturbance, biomass removal or fragmentation is discussed and evaluated. Other landscape factors taking part in ecosystem endurance like different structure and pH of soils or various microclimatic conditions are also taken in notice. It seems that intensity of human influence varies depending on it's nature and it is difficult to propose a linear scale of these changes. From this point of view German hemeroby concept is discussed as possibly suitable scale of human influence. Historical and present anthropogenic gradients in landscape - Abstract (EN) Ondřej Staněk, 2010
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Habitat characteristics accounting for the attractiveness of military training areas for birds: a case study from the Hradiště military training area
Hernová, Jana ; Reif, Jiří (advisor) ; Vojta, Jaroslav (referee)
Military areas are extraordinary biodiversity-rich due to limited economic activities and a specific way of using the areas for military training. Previous research has also revealed their positive influence on bird species diversity, this applies to endangered species in particular. However, the exact biotope characteristics attracting birds are insufficiently known. In this regard, I expected an important role of heterogeneity of the environment. The aim of the thesis was therefore: (I) to find out the difference of environmental heterogeneity between a military area (MA) and the surrounding landscape, both in a forest and a non-forest sites, (II) to find out what biotope characteristics attract birds in open landscape and (III) what characteristics attract birds in forest. Fieldwork took place in a still active MA of Hradiště and neighboring controls of Bochov and Ostrov. In total, 80 study plots were surveyed for representation of individual biotopes (39 types in total) and the number of fragments of woody vegetation. Data on bird species richness were taken from the thesis of Bušek (2015), surveyed birds at identical study plots and calculated total number of bird species and the number of endangered bird species at each plot. The open landscape of MA has, compared to the surrounding cultural...
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