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Diurnal changes of Rubisco activity under ambient and elevated concentrations of carbon dioxide
Uhrová, Lucie ; Vítová, Eva (referee) ; Hrstka, Miroslav (advisor)
Diurnal changes of Rubisco activity under the impact of ambient (380 µmol mol-1) and elevated (700 µmol mol-1) concentrations of carbon dioxide were studied in beech (Fagus sylvatica). Samples from leaves were taken in the two-hour intervals from 4:00 to 21:30 on the 22. 7. 2009 and activity of Rubisco was determined spectrophotometrically. No statistically significant differences were found between Rubisco activity of leaves growing in ambient and elevated CO2 concentrations. No increase of Rubisco total activity after daylight shows that nocturnal inhibitor CA1P is not present or plays only negligible role in beech. During the day Rubisco activity showed only statistically insignificant deviations. A slight decrease of Rubisco activation state in the afternoon indicates the afternoon depression of Rubisco initial activity.
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The impact of UV radiation on activity and content of Rubisco enzyme in beech
Cigánková, Michaela ; Urban,, Otmar (referee) ; Hrstka, Miroslav (advisor)
This bachelor thesis deals with the influence of UV radiation on content and activity of Rubisco enzyme in leaves of European beech (Fagus sylvatica). Plants were cultivated in ambient (UV), lower (UV-) and higher (UV+) UV-B radiation both at ambient (AC) and elevated (EC = 700 micromol mol-1) CO2 concentrations. Leaves sampling was done four times during the growth season, in the second part of July, at the beginning and in the end of August and in the middle of September. Rubisco activity was assayed spectrophotometrically, the content of Rubisco was determined by SDS-PAGE method and quantified by computer densitometry. The results confirmed a reduction of Rubisco content and down-regulation on Rubisco level at elevated CO2 concentration. With the exception of September sampling, the content of Rubisco was lower in UV+ at ambient concentration of CO2. The same was not demonstrated at elevated CO2 conditions. Hypothesis that UV-B radiation changes a ratio of large to small subunit of Rubisco was confirmed. The influence of UV-B radiation on Rubisco activity was not proved.
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Diurnal changes of Rubisco content and its activity under ambient and elevated concentrations of carbon dioxide
Matulková, Zuzana ; Zemanová, Jana (referee) ; Hrstka, Miroslav (advisor)
In this diploma thesis, the diurnal changes of initial and total Rubisco activity and Rubisco enzyme content in beech (Fagus sylvatica) were studied under conditions of ambient (A) CO2 concentration (350 µmol.mol-1) and elevated (E) CO2 concentration (700 µmol.mol-1) during the day. Samples were taken on July 8th (from 10:00 to 21:30), on July 9th (from 04:00 to 12:00) and then on July 22th (from 04:00 to 21:30). The initial and total activity were measured spectrophotometrically and the activation level was calculated from the ratio of initial and total activities. Rubisco enzyme content was determined by SDS-PAGE method and the initial and total specific activity were calculated from the ratio of initial or total activity and Rubisco enzyme content. In our experiment no statistically significant difference was found between Rubisco activities in beeches cultivated under conditions of ambient CO2 concentration and elevated CO2 concentration, so any down-regulation of Rubisco activity did not appear under the influence of ambient CO2 concentration. Diurnal changes of Rubisco activities showed only statistically nonsignificant fluctuation. After daylight no significant increase of total Rubisco activity was observed, which demonstrates the absence or the immaterial effect of CA1P night inhibitor in beech. Intensive fluctuation of the activation level (40–90 %) proves the regulation of photosynthesis during the day via Rubisco enzyme carbamylation. Rubisco enzyme content in beech cultivated under conditions of ambient CO2 concentration was lower than that one in beech cultivated under conditions of elevated CO2 concentration. Then down-regulation of Rubisco enzyme content is presented under conditions of ambient CO2 concentration. Before daylight Rubisco enzyme content showed an indistinctive minimum on the level of statistical significance, during the day only nonrelevant fluctuation was noticed.
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Influence of elevated carbon dioxide concentration at Rubisco activity and its content in sunny and shaded leaves of beech
Vičíková, Magda ; Vitoulová, Eva (referee) ; Hrstka, Miroslav (advisor)
This bachelor thesis focuses on influence of elevated carbon dioxide concentration at Rubisco activity and its content in sunny and shaded leaves of beech (Fagus sylvatica). The initial and total activities were measured spectrophotometrically, the content of Rubisco was determined by using SDS-PAGE method. It was observed statistically significant higher activity of Rubisco in leaves cultivated under elevated concentrations of carbon dioxide in June but not in September. In contrary, exposure of leaves (sunny/shaded) did not have significant influence on Rubisco activity in June, but in September was found lower activity of Rubisco in shaded leaves than in sunny leaves. The content of Rubisco was lower in leaves cultivated under elevated concentrations of carbon dioxide (acclimation), with the exception of shaded leaves in September. There was found significantly lower Rubisco content in shaded leaves than in sunny leaves both in June and in September.
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The dynamics of non-structural saccharides accumulation and Rubisco activity under the elevated carbon dioxide concentration and sink manipulation at beech
Uhrová, Lucie ; Vítová, Eva (referee) ; Hrstka, Miroslav (advisor)
This diploma thesis deals with dynamic of accumulation of non-structural carbohydrates and activity of Rubisco enzyme at elevated concentration of CO2 on beech (Fagus sylvatica L.). Three years old seedlings of beech were cultivated in minisphere with ambient (385 µmol•mol-1, variant A), and with elevated concentration CO2 (700 µmol•mol-1, variant E) for four months. In every variant the first half of plants was fertilized by nitrogen (variant N+) and the second half was control (variant N-). Plants used for experiment were at first adapted for darkness for 12 hours. Subsequently tested leaves were cut off, leafstalk including short segment of branch (approximately 1 cm) was inserted into 0.7 M solution of sucrose (variant S) or water (variant V) and exposed to radiation 200 mol•m-2•s-1 for 0, 30, 60, 120, 180 minutes. Then leaf area and fresh mass of leaf blade were established, samples were fixed in liquid nitrogen and stored in deep freezer to analysis in –70 °C. Rubisco content was determined by SDS-PAGE method, Rubisco activity spectrofotometrically and content of non-structural carbohydrates by anthrone method and HPLC method. Rubisco content was significantly lower in the N- variant than in N+ variant. Rubisco content was also significantly lower in E than in A variant, which is an evidence of down-regulation. Rubisco activity is moderately stimulated at E variant with time, but differences between variant A and E are not statistically significant. Influence of sucrose feeding to Rubisco activity was not proved. Significant differences were detected by anthrone method in non-structural carbohydrates content between variants S and V, but not between variants A and E. Statistically significant increase of sucrose content with time was detected by HPLC method at variant AS, but not at variant ES.
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Biotopové nároky lejska malého (Ficedula parva) v lesích jižní a východní Moravy
Holek, Michal
This study investigates the habitat requirements of the Red-breasted Flycatcher at 41 sites in the Drahanská vrchovina, Chřiby, Hostýnsko-vsetínská hornatina and Bílé Karpaty based on the observed abundance of the species in the breeding season 2022. At the sites, the locations of its occurrence and the locations of checkpoints without the presence of the lei were recorded inside and outside the site. Stand characteristics were then collected at these points and then analysed for their statistical significance for the species' occurrence. Forty-seven Red-breasted Flycatchers were recorded at the study sites. Distance from water, forest development stage, amount of dead wood, distance from the edge of the stand and beech (Fagus sylvatica) cover had a significant effect on the occurrence of the Red-breasted Flycatcher. Distance from water emerged as the most significant characteristic, with 51 % of individuals found within 90 m of a watercourse. Red-breasted Flycatcher preferred emergent and, to a lesser extent, mature logs with significant amounts of dead wood. These were mainly stands with beech cover above 80 %. The Red-breasted Flycatcher was shown to be an interior-nesting species, as 85 % of individuals were found more than 100 m from the edge of the stand. The thesis concludes by discussing the findings and comparing them with the literature. From the results, recommendations for forest management are proposed for effective conservation of the Red-breasted Flycatcher in forest habitats.
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Vliv chemické modifikace na vybrané vlastnosti dřevěné pružiny
Novák, Filip
This thesis focuses on the influence of chemical modification on a wooden spring.The spring was made of beech wood (Fagus sylvatica, L.). Bending ratio was chosen 1:4 thickness to radius. The effectiveness of the chemical modification with acetic anhydride was measured by weight percentage gain (WPG). Acetylation was made with 18 % WPG (at full acetylation 25 % WPG was observed damage of bent wood mostly by compression stress). Chosen spring properties was evaluated in four moisture states (dry, in condition of 65 %, 85 % and 99 % relative humidity and temperature 20 °C). Influence of acetylation on mechanical properties was proven. In wet condition acetylated samples proved higher shear modulus of elasticity a higher rigidity of spring. In dry condition acetylated samples proved lower shear modulus of elasticity a lower rigidity of spring. Influence of acetylation on dimension stability was proven. Acetylated samples proved reduction of equilibrium moisture content (46-56 %) in comparison to reference samples. Acetylated samples proved swelling reduction in radial direction (41-56 %) and in tengential direction (46-59 %). More regular swelling (ratio of radial and rangential) was observed at acetylated samples. Influence of acetylation on shape stability was proven. Shape stability of acetylated spring was evaluated by change in diameter of spring in different moisture states. Wet conditions caused enlargement of acetylated spring diameter (5-16 %) and of reference spring diameter (10-40 %). Reduction of shape changes was observed (57-75 %).
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Výskyt a hodnocení zdravotního stavu hlavních edifikátorů lesních porostů v oblasti Přírodní lesní oblasti č.16 Českomoravská vrchovina
Krajíčková, Dominika
In 2021, the representation of European beech (Fagus sylvatica) in the Czech Republic was 9.3 %, of maples 1.6 % and oaks 7.6 %. These values are slowly increasing, and the representation of European beech has increased by 3.3 % of the total area of arable land over the last five years (Zelená zpráva 2021). This work discusses the life manifestations of European beech (Fagus sylvatica), Norway maple (Acer platanoides), Sycamore maple (Acer pseudoplatanus) and Pedunculate oak (Quercus robur) in selected small protected areas in the Natural Forest Area No. 16 of the Czech-Moravian Highlands. The aim of this work is to evaluate the life manifestations of the above-mentioned tree species. Three small protected areas were selected, of which two localities are located in the 5th forest vegetation tier and one partially in the 5th and 4th forest vegetation tier, and endometrial measurements were performed here. The result was a comparison of the obtained data between individual sets of forest types and individual tree species on the set of forest types 5J. The diameter of the trunk and the height of the beech crown deployment were lower at 5K. The Norway maple reached smaller thicknesses at 5J compared to the other trees, on the contrary, the Sycamore maple and Pedunculate oak reached greater heights.
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Hodnocení stavu lesních geobiocenóz přírodní rezervace Palkovické hůrky (okres Frýdek-Místek)
Žáček, Pavel
The aim of this thesis was to determine the current state of forest stands in the territory of the PR of Palkovické hůrky. On established areas, perform control measurements of dendrometric characteristics and perform phytocenological imaging on the most widespread forest types. As part of the field investigation, assess the occurrence of forestry-significant pests and pathogens on individual tree species. The results of individual phytocenological images show that herb species diversity has decreased in 75 % of forest types. However, the total cover of these species was reduced to only 58 % of forest types. From individual measurements on dendrometric plots, it was found that the vegetation stock increased in 66 % of cases. If there was a decrease in the vegetation stock, it was solely due to the death of a large number of individuals of Norway spruce, mountain elm or Norway ash. The highest increase in stock occurred in forest type 4S1, where the stock doubled. The significant die-off of spruce contributes to the improvement of the evaluation of the naturalness of forests. In the future, in the nature reserve Palkovické Hůrky, there is an assumption that within the framework of this assessment, a forest close to nature will become a natural forest. Finally, according to the facts and findings, forestry management was proposed in the given natural conditions.
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Mortalita podsadeb buku lesního a jedle bělokoré vyzvednutých z přirozené obnovy
Gattnar, Matyáš
The main aim of this bachelor thesis was to evaluate the mortality of seedlings of white fir (from three different natural forest areas) and beech, which were collected and transplanted under spruce forest. The research was carried out in the Moravian-Silesian Beskydy Mountains in the Kyčera area, which is under the administration of the Forestry Service of the Czech Republic. Two decaying spruce monocultures were used. Several variants of forest beech and white fir from three different natural forest areas (Beskydy, Jeseník, Žďár) were planted on the nutrient habitats. The best results were obtained for the variant of rooted beech, which was planted in the spring of 2022. Of the fir trees, those taken from the Beskydy area fared best.
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