National Repository of Grey Literature 95 records found  previous11 - 20nextend  jump to record: Search took 0.01 seconds. 
Vývoj společenstva ektomykorhizních hub na 4 trvalých plochách horských smrčin NP a CHKO Šumava narušených disturbancemi
KREJČÍKOVÁ, Jitka
The aim of this thesis is to describe the development of ectomycorrhizal fungal communities at 4 study plot in mountain spruce forests after different level of disturbances located in National Park and Protected Area Šumava
Effect of climate change on hydrological extremes in montane catchments
Čermák, Daniel ; Langhammer, Jakub (advisor) ; Jeníček, Michal (referee)
This master thesis deals with the issue of low-flows in mountain catchments in the context of expected climate change. The Zdobnice, Vydra and Mumlava river basins are selected for analysis. In the first part of thesis, the meteorological and hydrological historical data are evaluated. This data are obtained from CHMI (Czech Hydrometeorological Institute). The work also focuses on estimating the possible change in flow rates in the distant future (2100). For these purposes, the conceptual model HBV is used. This model is often used for these types of analyzes due to its robustness. To evaluate the change, twelve alternative scenarios were created. These scenarious were based on the results of global and regional climate models related to each selected river basins. The model was calibrated using the automatic GAP optimization function. Based on the best results, the calibration period is set for the years 1980 - 1998. Climate models suggest increase of temperature in far future by 1.5 ř C - 4.5 ř C. At the same time, according to climate models, we can approximate a total precipitation change by 10 %. Based on climate changes, a shift in the runoff seasonality in the all river basins is evident. Seasonality change is most visible in the Zdobnice river basin. In terms of hydrological drought, an...
Detection of the forest disturbance using UAV multispectral photogrammetry
Minařík, Robert ; Langhammer, Jakub (advisor) ; Hofierka, Jaroslav (referee) ; Miřijovský, Jakub (referee)
Epidemic (calamitous) overpopulations of bark beetles (Scolytinae Latreille, 1804) caused by climate change and inappropriate tree species composition currently have the most negative impacts on the development of Europe's mixed and boreal forests. Epidemic overpopulations can significantly undermine forest health and cause economic losses. It is therefore essential to use appropriate methods for early detection of bark beetle disturbance. Multispectral remote sensing (RS) methods using unmanned aerial systems (UAS) represent a new option for contactless landscape monitoring providing quantitative information on vegetation health with high spatiotemporal resolution and therefore appear to be suitable for early detection of disturbance. The thesis focused on the validation of the use of UAS multispectral photogrammetry and image classification methods for the detection of individual forest disturbance stages caused by the spruce bark beetle (Ips typographus Linnaeus, 1758) at the level of individual trees for the study of disturbance dynamics. In this dissertation, all important aspects of detection were elaborated: analysis of the suitability of spectral bands for disturbance detection, radiometric calibration of multispectral cameras, automated segmentation of individual canopies from...
Natural regeneration of spruce stands in Vysoké Tatry (High Tatras) after large scale disturbation
Michalová, Zuzana ; Weiser, Martin (advisor) ; Wild, Jan (referee)
The observational study on natural regeneration of Norway spruce (Picea abies) was provided during seasons 2010 and 2011 in the windthrow area of High Tatra National Park. The main aim of this master thesis was to describe the distribution pattern in Norway spruce regeneration as well as to estimate the spatial scale, which most preciselly describes the differences in its phenotypic variability. Following step was to determine the relative influence of abiotic and stand factors on the growth characteristics and abundance of spruce seedlings. The Main focus lied on stressing the role of biotic interactions, like intraspecific and interspecific competition, leading to certain discrepancies in the phenotype, as well as in abundance of spruce seedlings.The reponse in variability in spruce traits was recognized at each spatial level. The results showed clear causality between soil moisture and vegetation composition, which both directly modified not only the phenotype of spruce seedlings and plants, but have even influenced their counts on particular stands.
Perception of the human disturbance by ungulates in the wild and in the captivity
Šťastná, Tereza ; Komárková, Martina (advisor) ; Frýdlová, Petra (referee)
The relationship between ungulates and humans has been evolving ever since the first predator's interaction with the prey, leading to the current domestication. The behavior of ungulates differs based on the human disturbance. The goal of this thesis was to compare the reactivity to humans of selected species in nature vs. in captivity and determine its correlation, inter or intraspecific. The thesis indicates reactivity to humans of specific species of ungulates (donkeys, horses, reindeers and goats). Following reactions were chosen for comparison: vigilance, alert distance, flight and avoidance distance. There are several acting factors like previous experience with humans, habituation, group size or season. With group size, the vigilance decreased, which was proven with donkeys, reindeers and goats. The behavior differed based on the season by resources availability, offspring's presence in herd (higher vigilance) or rut (lower vigilance). In captivity, there were less human contact avoidance, while the experimenter was known. Based on researches, ungulates tend to avoid humans more in nature, than in captivity. Sources claim, that among chosen ungulates, the most vigilant in both nature and captivity are reindeers. Further researches could later consider the human perception according to the...
Seasonal and long-term dynamic of plankton communities of small water-bodies
Pejsar, Patrik ; Černý, Martin (advisor) ; Juračka, Petr Jan (referee)
Zooplankton pool-inhabiting organisms form metacommunities and metapopulations. Locations are connected through dispersion which is an essential part of colonization-extinction dynamic. Locations vary with the environmental conditions, the specifics of the community and the biotic interactions taking place there. Differences in these parameters may occur between spatially separated pools or in one pool throughout time. These changes are caused by seasonal dynamics, disturbances, long-term development of environmental conditions or biotic factors such as predation, competition and parasite influence. On a long-term scale the locations are classified into rather stable and ephemeral. In pool environment the ephemeral locations may unexpectedly be the driving force of metacommunity and metapopulation processes according to the "inverse mainland-island" theory. Global climate change has an essential influence on zooplankton dynamic in smaller water-bodies. Hydrology of pools and through it also life dynamics of plankton organisms is directly influenced by temperature changes and precipitation. Regional metacommunity and metapopulation dynamics are changing in dependency on regional course of climate change and the specifics of these water-bodies and the communities living there.
Dendrochronological dating of catastrophic slope movements
Tumajer, Jan ; Treml, Václav (advisor) ; Burda, Jan (referee)
Mass-movements are one example of natural processes that can pose a serious risk for human beings and their possessions. Dendrochronology, a method capable of their reconstruction, can provide parameters of former events, which can be used for planning protective measures. The possibilities for the application of dendrochronological methods have been tested by means of meta-analysis of electronic and printed scientific articles and a case study focused on former avalanche activity in Schustler's avalanche path (Labský důl, Krkonoše Mts.). The main conclusion of the first one is the clear spatial disproportion of the recent dendrogeomorphological research activities - e.g. the dating of avalanches is typical for mountains of Montana (USA); the Alpine region (mainly Switzerland), on the other hand, absolutely dominates in the research of debris-flows. In the case study, the analysis of material with well-chosen indicators led to high accuracy results comparable with the results of scientific articles focused on avalanches, and made the identification of 14 years (in the period 1953-2007) with potential avalanche acitvity possible. Although methods of dendrogeomorphology are usually neglected in the research of avalanches in the Czech republic, their great potential for future applications is shown....
Impact of forest disturbance and management on surface runoff
Šmrhová, Zuzana ; Langhammer, Jakub (advisor) ; Váňová, Věra (referee)
Impact of forest disturbance and management on surface runoff Abstract The main aim of this work is to evaluate the current national and foreign literature regarding the impact of the forest disturbance and the forest management on runoff process. The disturbance and methodology, which is used for evaluation of their impact on runoff, is described in the research part of this work. The work is applied to model locations in the central part of umava Mountains, where is mapped and described the health status of the forest for the individual river basins. The scope of this work is to evaluate the behaviour of selected model basins during precipitation situations and demonstrate the influence of the forest health status on character of the flow. Key words: forest, disturbance, management, land use, runoff, GIS
How do bird species richness and abundance differ between military training areas and surrounding landscape? A case study from the Hradiště military area
Bušek, Ondřej ; Reif, Jiří (advisor) ; Koleček, Jaroslav (referee)
Since the beginning of the 20th century human land use changed drastically in Central Europe. These changes included: homogenization of the landscape mosaic, intensification of agriculture, urbanization and land abandonment. In turn, these changes affected bird species and perhaps most significantly manifested in population decline of open habitat birds. Therefore, it is important to investigate sites, which were not affected by the changes mentioned above, such as military training areas (MTAs) - places dedicated to training of armed forces. Previous studies have shown that MTAs seem to host remarkably high bird diversity and abundant populations of bird species of conservation concern. This may be caused by two major factors. First, closure of MTAs to all human activies besides military training spared them of the landscape changes mentioned above. Second, the military training itself produces a very heterogeneous habitat mosaic that allows coexistence of many species with different ecological requirements. To my knowledge, no study compared bird assemblages between MTAs and surrounding landscape directly. At the same time, such data are crucial to assess the value of MTAs for bird conservation reliably and, as a consequence, they enable to think more deeply about mechanism generating this value....
Effects of wild ungulates on vegetation in an abandoned landscape
Horčičková, Eva ; Herben, Tomáš (advisor) ; Diekmann, Martin (referee) ; Tichý, Lubomír (referee)
Wild ungulates are considered one of the major drivers for shaping terrestrial ecosystems, which has been developing since the early Cenozoic. Understanding the effects of ungfulates on vegetation is necessary for qualified knowledge how European landscape looked prior to human habitation and how it would look like without human intervention. Further, such understanding is of practical importance as management information necessary for managing abandoned landscapes. While the present-day wild ungulate European fauna does not contain several large grazers like auroch (Bos primigenius) anymore, the landscape has long been affected by them. It thus possesses historical experience of response to large grazers, which has been further maintained by livestock grazing. Importantly, the European landscape is experiencing a steady increase of populations of deer (Cervidae) and wild boar (Sus scrofa) with major effects of vegetation and landscape structure. While the effects of these present-day dominants have been studied mainly in forest habitats, there is a growing evidence that they both promote species diversity of forest understory and, interestingly, preferably feed in open vegetation and thus can affect broader landscape heterogeneity. The main aim of this thesis is therefore to examine effects of...

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