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Effect of elevated CO2 on morphological and photosynthetic parameters in two understory grass species in Beskydy Mountains
Holub, Petr ; Klem, Karel ; Urban, Otmar
We transplanted two grass species, Calamagrostis arundinacea and Luzula sylvatica, to the understory of\na 10-year-old experimental mixed forest exposed to ambient (385 μmol CO2 mol–1, AC) and elevated (700\nμmol CO2 mol–1, EC) atmospheric CO2 concentration using a glass dome facility. Effects of EC on plant\nmorphology and photosynthesis were examined after three years of treatment. We tested the hypotheses\nthat shade-tolerant species can profit from EC even at low light conditions and that relatively low accumulation\nof assimilates at such light conditions will not cause CO2-induced down-regulation of photosynthesis.\nWe expected that EC can substitute insufficient light intensities under the tree canopy and lead to both\nhigher biomass production and survival of plants in deep forest understories. The typical shade-tolerant\nspecies L. sylvatica exhibited positive acclimation under EC allowing higher light use efficiency under subsaturating\nlight intensities as compared to plants grown under AC. In contrast, C. arundinacea showed\nhigher stimulation of growth and photosynthetic rates by EC mainly under saturating light intensities at\nthe beginning of the growing season, when the forest leaf area is not fully developed and the open canopy\nallows a greater proportion of incident light to reach the understory. Our data indicate that growth and\nphysiological responses of EC plants in forest understories are species specific, differ from responses of\nsun-exposed plants, and depend on degree of shading.
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European specifics of the art of percussion instruments: Basics of natural playing
Zhdanovich, Anton ; MIKOLÁŠEK, Daniel (advisor) ; Holub, Petr (referee)
This work is a summary of the information and knowledge about the basics that make up the present tradition of playing percussion instruments in Europe (predominantly Western). Its main purpose is to support the development of percussion instruments in Czech Republic, especially in schools, where the playing level is in the development stage and needs to be supported from other sources. During my Master's study at HAMU (2014-2017), I took part in many of international events in this field, which were focused on the development of young musicians of my generation on musical, technical, mental and aesthetic side. The obtained information by feedbacks and comments from leading teachers and performers in the field is the absolute basis for this work. Awareness of the principles and basics that will be written here requires a presence of certain musical and life experiences, so this work is intended for the age category from the students of secondary vocational schools and above.
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Methods for identification of vulnerable zones for nitrogen leaching in arable land
Zemek, František ; Pikl, Miroslav ; Holub, Petr ; Klem, Karel ; Záhora, J. ; Vavříková, J.
The methodology demonstrates on the case study of a catchment (cca 200 km2 in size) how to identify the areas with high risk of nitrogen (N) leaching to underground water in arable land. It uses synergy between “conservative” characteristics of the catchment, such as orographic features, bedrock and soil hydrological properties, and the dynamic ones, which are represented by vegetation properties. The latter are identified through the imaging spectroscopy of wheat canopy obtained from airborne hyperspectral and/or Sentinel-2 multispectral data.
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The Town book of Pacov from the 1475-1683
Holub, Pavel ; Ebelová, Ivana (advisor) ; Sulitková, Ludmila (referee)
6 Annotation The aim of the thesis is to introduce an urban book of Pacov in term of a diplomatic analysis. This urban book was established from the second half of 15 century to the second half of 17th century. The actual analysis of the registers is introduced by two sub-chapters. The first one is focused on the socio-politico-administrative development of the areas of Pelhřimov and Pacov during the late medieval and early modern period. The environment of Pacov is directly reflected in the section devoted to municipal laws, which aim is to put the content of privileges issued for Pacov to a broader social context. The sub-sections describing the outward signs of the urban book, an analysis of the registers from a diplomatic-content analysis point of view and the urban book in the context of the written production of the municipal office are the central part of the analysis of the urban book of Pacov. The groups sorting of different types of registers is based on the structure of municipal book as Ludmila Sulitková has applied to the urban environment of Brno books in the context of the urban book development in the Middle Ages. This classification is based on the results of a longtime research, whose origin can be associated with Václav Vojtíšek. The main consideration in the discussion of each register...
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Hydrodynamic mixing of water-ask mixture in vessel
Holub, Přemysl ; Franc, Zdeněk (referee) ; Habán, Vladimír (advisor)
Master´s thesis Hydrodynamic mixing of water-ash mixture in vessel is interested in describing fluid and solid particles flow in a vessel. The mixing was conducted in cylindrical vessel by a radial nozzle. The goal of the thesis is to describe flow field and places where the most of the particles are descending according to position, depth, flow rate and nozzle orientation in the vessel. An experiment was conducted in order to investigate and document 8 different positions and orientation of the nozzle. Significant changes in flow fields and mixing time were observed. A mathematical model of the vessel with the nozzle was created in Fluent program. Places with the lowest velocities according to the model were in good agreement with places where the most of the solid particles were descending.
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Control Systems of Gears Changing on Load in Tractors Gearboxes
Holub, Přemysl ; Svída, David (referee) ; Dundálek, Radim (advisor)
This bachelor thesis is interested in the overview of tractor’s gearboxes, which are changing on load. There are reasons, why it has to be costructed and there are requirements for it. There are also described PowerShifts, which allow us gear changing on load. After basic description of concrete gearbox, there is always some example of using in current tractors. In period named Mechanical gearboxes, wchich are changing partly on load there is more space for Zetor tractors and its gearboxes. In one of the last period there is important part about continuously variable transmissions where the driving speed is regulated steplessly. These gearboxes are considered to be modern technology of transfer engine torque.
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The effect of drought and nitrogen fertilization on the production, morphometry, and spectral characteristics of winter wheat
Trunda, Petr ; Holub, Petr ; Klem, Karel
Methods of study based on the spectral reflectance of vegetation are now commonly used in researching both natural ecosystems and field crops.The aims of this experiment were to evaluate the effect of drought and nitrogen (N) fertilization on N use efficiency in winter wheat and use the obtained spectral characteristics to assess stand heterogeneity as a potential consequence of different crop nutrition. Twelve experimental plots of winter wheat were manipulated to drought from 8 May 2013 to 12 June 2013. The effect of drought was observed in two treatments: control without fertilization (N0; 0 kg N ha−1) and N fertilization (N140; 140 kg N ha–1). Plant samples were then taken for determination of above-ground biomass and N content in dry matter. Spectral characteristics of wheat were measured in the earing phase at canopy level. The effect of drought on the morphometric parameters of winter wheat was statistically significant only on N-fertilized plots (N140). Total above-ground biomass decreased by a significant 18% in the N140 treatment as a result of the simulated drought. This decrease was reflected in statistically significant reductions of all individual plant parts (stems, leaves, spikes) in N140. Responses to drought stress were observed in many vegetation indices, particularly in NDVI, GNDVI, and WI/NDVI. The results show there are significant relationships between N content in the grain and vegetation indices. A quite marked separation was observed in the relationships between dry and ambient treatments for vegetation indices NRERI, TCARI/OSAVI, VOG2 and GM. Generally, the impact of drought increased at higher levels of N content in the grain, which corresponded with the results of morphometric analysis. Use of reflectance in the study of vegetation and field crops regarding risk assessment of mineral N leaching from soils has considerable potential especially in mapping large areas and monitoring temporal changes relating to N release.
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Interactive effects of UV radiation and drought on the accumulation of flavonols in selected herbs and grass in a mountain grassland ecosystem
Veselá, Barbora ; Surá, Kateřina ; Rajsnerová, Petra ; Klem, Karel ; Holub, Petr ; Urban, Otmar
The main objective of this 4-year experiment conducted in a mountain grassland ecosystem was to investigate the interactive effects of ultraviolet (UV) treatment and drought on changes in accumulation of UV-screening compounds (flavonols) in selected herbs (Hypericum maculatum Crantz, Rumex obtusifolius L.) and grass (Agrostis tenuis Sibth.). Inasmuch as drought and UV radiation induce similar protective mechanisms, we tested the hypothesis that UV radiation and drought elicit synergistic effects on flavonol accumulation. The experimental plots were manipulated using rainout shelters enabling the exclusion and transmission of incident precipitation and UV radiation. Generally, UV and drought treatments had similar effects on flavonol accumulation. For R. obtusifolius, UV exclusion resulted in a substantial reduction of UV-screening compounds, particularly under ambient precipitation conditions, while for H. maculatum and A. tenuis UV exclusion caused only a slight reduction of flavonol content. Similarly, the drought treatment caused an increase in flavonol accumulation.
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Convergence of morphological, biochemical, and physiological traits of upper and lower canopy of European beech leaves and Norway spruce needles within altitudinal gradients
Rajsnerová, Petra ; Klem, Karel ; Večeřová, Kristýna ; Veselá, Barbora ; Surá, Kateřina ; Rajsner, Lukáš ; Holub, Petr ; Urban, Otmar
Climatic variation along altitudinal gradients provides an excellent natural experimental set-up for investigating the possible impacts of climate change on terrestrial organisms and ecosystems. The present work has explored for the first time the acclimation of upper versus lower canopy leaves or needles in European beech (Fagus sylvatica) and Norway spruce (Picea abies) forests along an altitudinal gradient. We tested the hypothesis that restrictive climatic conditions associated with high altitudes reduce within-canopy variations of leaf traits. The investigated beech and spruce forests were located on the southern slope of the Hrubý Jeseník Mountains (Czech Republic). All measurements were taken on leaves from the upper and lower parts of the canopy of mature trees (>60 years old) growing at low (400 m a.s.l.), middle (720 m a.s.l.), and high (1,100 m a.s.l.) altitudes. Generally, we observed that with increasing altitude, which is associated with adverse microclimatic conditions, a convergence of CO2 assimilation rate and other physiological, morphological, and biochemical characteristics between the upper and lower canopy occurred. However, differences in altitudinal response among individual traits and species were found. Such plasticity in acclimation of leaves and needles has the potential to cause substantial change in the photosynthesis of individual parts of forest canopies within the vertical profile and their contribution to the overall carbon balance of vegetation.
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