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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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Timpani technique by Fred D. Hinger
Zhdanovich, Anton ; MIKOLÁŠEK, Daniel (advisor) ; Holub, Petr (referee)
This bachelor thesis focuses on contemporary problems of primarily orchestral timpani playing. In this thesis, I tried to explain, why a timpani player is often unable to reach the desired quality of sound and tone of the instrument, which make it impossible to reach the right musical character in the context of that particular musical piece.
The goal of this work is to enrich the Czech school of timpani playing and to contribute to the growth of interpretation abilities of beginning and intermediate timpani players. Another goal is to show a different tradition of kettledrum playing with all its details.
I focused on the practical side of the instrument playing and I describe the methods and the process of solving technical and musical problems of interpreters in this paper.
The character of this thesis is completely practical and focuses on the description of one of the many other world traditions of timpani playing.
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Effects of UV radiation and drouhgt on the accumulation of UV-screening compounds and photosynthetic parameters in selected herbs and grasses of the mountain grassland ecosystem
Klem, Karel ; Holub, Petr ; Urban, Otmar ; Rajsnerová, Petra ; Kubásek, Jiří
The main objective of the experiment conducted on a mountain grassland ecosystem was to investigate the interactive eff ects of UV treatment and drought on the changes in accumulation of UV-screening compounds and photosynthetic parameters in selected herb (Hypericum maculatum) and grass (Agrostis tenuis) species. Th e experimental plots were manipulated using roof constructions enabling exclusion or transmission of incident precipitation and UV radiation, respectively. Generally, UV and drought treatments had a similar eff ect on the accumulation of fl avonols. UV exclusion resulted in a slight reduction of UV-screening compounds, particularly under the conditions of ambient precipitation. Likewise, drought treatment caused an increase in the accumulation of fl avonols per area unit. Under UV exclusion, drought slightly reduced the light-saturated CO2 assimilation rate (Amax) in both the species studied. Th e presence of UV radiation, however, led to less of a diff erence in Amax between [wet] and [dry] treatments. In addition to the increased induction of fl avonols, UV radiation increased water use effi ciency and alleviated thus the negative impact of drought on photosynthesis.
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Vliv hospodářských zásahů na změnu v biologické rozmanitosti ve zvláště chráněných územích: Vliv různých managementových zásahů na vegetaci vřesovišť v Národním parku Podyjí II.
Mendelova zemědělská a lesnická univerzita v Brně, Ústav půdoznalství a mikrobiologie, Brno ; Masarykova univerzita v Brně, Přírodovědecká fakulta, katedra botaniky, Brno ; Botanický ústav AV ČR, Průhonice, pracoviště Brno ; Záhora, Jaroslav ; Chytrý, Milan ; Tůma, Ivan ; Holub, Petr ; Sedláková, Iva
V roce 1992 byly založeny pokusy, které měly ověřit, zda vypalování, kosení a odstraňování drnů jako tradiční typy managementu západoevropských vřesovišť povedou k obnově a zmlazení vřesovišť v NPR Podyjí. Dále bylo v roce 2000 založeno 30 nových ploch na studium vlivu pastvy a kosení. Od roku 2000 je také sledována dynamika mikrobiálních transformací dusíků v půdě, rychlost rozkladu opadu a efektivita využití N a P rostlinami. V roce 2001 byly na vřesoviště naistalovány srážkoměry.
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Vliv hospodářských zásahů na změnu v biologické rozmanitosti ve zvláště chráněných územích: Vliv různých managementových zásahů na vegetaci vřesovišť v Národním parku Podyjí III.
Mendelova zemědělská a lesnická fakulta v Brně, Ústav půdoznalství a mikrobiologie, Brno ; Masarykova univerzita v Brně, Přírodovědecká fakulta, katedra botaniky, Brno ; Botanický ústav AV ČR, Průhonice, pracoviště Brno ; Záhora, Jaroslav ; Chytrý, Milan ; Fabšičová, Martina ; Tůma, Ivan ; Holub, Petr ; Sedláková, Iva
Pokusy mají za cíl otestovat některé metody managementu vřesovišť: vypalování, pokosení drnů, pastvu. V této vegetační sezóně bylo sledováno celkem 38 trvalých ploch na vřesovištích v NP Podyjí. Od r. 2000 je také sledována dynamika mikrobiálních transformací dusíku v půdě, rychlost rozkladu opadu a efektivita využití N a P rostlinami.
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Manager development needs in contemporary human resources management
HOLUB, Petr
The aim of this thesis is specification of new views and demands influencing formation and development of managers in today´s management of human resources. In order to obtain the necessary data, an information probe was created and managers were given a questionare concerning personality developement of managers.
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