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Response of tree rings and NDVI of Central-European conifers to extreme climatic events
Mašek, Jiří ; Treml, Václav (advisor) ; Šilhán, Karel (referee) ; Piermattei, Alma (referee)
Terrestrial ecosystems, mainly forests are important sinks of atmospheric carbon with high year-to-year variability driven by moisture availability. Trees store carbon in various compartments of the biomass, namely in stems, roots, and leaves. In this doctoral thesis, I investigated climate-growth responses of stem biomass (represented by tree rings) and leaf biomass (represented by normalized difference vegetation index; NDVI) of Pinus sylvestris and Picea abies in temperate forests of Czechia. I was interested in (i) general climate-growth responses and specifically, in reactions to drought and (ii) topographical factors influencing these responses at various spatial scales. We demonstrated that climate-growth responses of both species' tree rings in the lowlands revealed a significant positive and negative influence of moisture and temperature, respectively, while in higher elevations the responses were opposite. At a landscape level, the topography of relief modulated responses of Pinus sylvestris tree rings, while at the large-scale level, the geographical position and elevation (temperature gradients) were the main factors for both species. Responses of NDVI were slightly weaker compared to tree rings and did not show the influence of topography at any scale probably because vegetation...
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Dynamics and spatial extension of recent landslides at the foot of Krušné Hory Mts.
Burda, Jan ; Vilímek, Vít (advisor) ; Kirchner, Karel (referee) ; Šilhán, Karel (referee)
Dynamika a rozšíření recentních svahových pohybů na úpatí Krušných hor | Abstrackt 1 ABSTRACT Recent mass movements currently comprise one of the main morphogenetic processes in the extensive anthropogenic relief of the foreground of the Krušné Hory Mountains in the Czech Republic. These mass movements result in several types of deep- seated slope failures, depending on the type of movement, lithological, structural, and geotechnical conditions and the water saturation of the landslide material. This thesis presents broad set of various methods of geomorphology, geophysics, engineering geology, dendrogeomorphology and geodesy in an attempt to fully understand the problem of slope failures in the Jezeří area located at the boundary between the Krušné Hory Mountains and the Most Basin (Czech Republic). An interdisciplinary approach has enabled an in-depth review of both the dynamics and development of recent slope failures as well as morphology and structure of slope failures. There are two sectors - Southeast and Southwest - with different types of slope failures. In the Southwest sector, mass movements occur in thick colluvial mantle and weathered Tertiary claystones. The main factors influencing their development include rainfall culminations, groundwater flowing from the valley of Šramnický Brook and...
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