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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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Influence of total leaf nitrogen and non-structural carbohydrates on Rubisco content and its activity under ambient and elevated concentrations of carbon dioxide
Vičíková, Magda ; Babák, Libor (referee) ; Hrstka, Miroslav (advisor)
This diploma thesis examines influence of content of leaf nitrogen and non-structural carbohydrates on Rubisco activity and its content under impact of ambient (A = 385 µmolCO2 mol-1) and elevated (E = 700 µmolCO2 mol-1) concentrations of carbon dioxide in needles of Norway spruce (Picea abies L.). The Rubisco activity was determined spectrophotometrically, the Rubisco content by using SDS-PAGE, the content of non-structural carbohydrates by using the anthron method and total leaf nitrogen was determined by using the Kjeldahl method. The Rubisco activity in needles of Norway spruce did not show acclimation on elevated concentration of carbon dioxide, but the activity was elevated concentration of carbon dioxide stimulated during the growing season. The acclimation was proved by Rubisco content, its content was significantly lower in needles cultivated under elevated carbon dioxide. Content of total leaf nitrogen was statistically significantly lower in needles of Norway spruce cultivated under elevated carbon dioxide then in needles cultivated under ambient concentration of carbon dioxide. On the contrary, the content of non-structural carbohydrates was significantly higher in needles cultivated under elevated concentration of carbon dioxide then in variant A. Seasonal changes of Rubisco content depended on content of non-structural carbohydrates, the Rubisco content decreased with increasing content of non-structural carbohydrates. No dependence was detected between seasonal changes of the total leaf content and the Rubisco content.
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Influence of elevated carbon dioxide concentration at Rubisco activity and its content in sunny and shaded needles of Norway spruce
Šibravová, Lenka ; Zemanová, Jana (referee) ; Hrstka, Miroslav (advisor)
Diploma thesis’s aim was to determine Rubisco activity and its content in sunny and shaded needles of Norway spruce (Picea abies [L.] Karst.) and confirm or refuse acclimation on Rubisco enzyme level. Samples were taken on the Experimental ecology station Czech Academy of Sciences at Bílý Kříž (Beskydy Mountains) where needles were cultivated in two cultivation spheres with different concetrations CO2. One cultivation sphere contains atmosphere with ambient (A) concentration CO2 (350 mol CO2 mol-1) and the other contains atmosphere with elevated (E) concentration CO2 (700 mol CO2 mol-1). Rubisco activities were determinated spectrophotometric, Rubisco content was determined by SDS-PAGE method. Samples were taken in the modele of June and in the end of September. Elevated concetration CO2 did not have significant influence on Rubisco activity. Whereas different exposition had significant influence on Rubisco activity in June, when was found lower Rubisco activity in shaded needles than in sunny needles. In September were not find significant differences in Rubisco activity beetwen sunny and shaded needles. We did not find statistically significant differences in Rubisco content between A and E needles in June. Incontrary, we found about 34 % lower Rubisco content in E needles than in A needles, which confirms acclimation on Rubisco enzyme level. In September Rubisco content was several time higher than in June, which evidences the long term building photosynthetic apparatus in coniferous trees.
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Influence of needle age at Rubisco activity and content in Norway spruce under the impact of ambient and elevated CO2 concentrations
Bošková, Martina ; Vítová, Eva (referee) ; Hrstka, Miroslav (advisor)
In this diploma work influence of needle age at Rubisco activity and content in Norway spruce (Picea abies) was studied. The plants were cultivated in conditions with ambient (A) CO2 concentration (350 µmol CO2/mol) and elevated (E) CO2 concentration (700 µmol CO2/mol). Sampling was done two times during the growing season (in the middle of June and in the end of September) were taken. Initial and total Rubisco activities were measured spectrophotometrically. Rubisco content was determined by SDS–PAGE method. Rubisco activity in 18-months-old needles was in E higher than in A. Rubisco contents in current-year needles and one-year-old needles were in A higher than in E in September. These differences were statistically significant that demonstrates the down-regulation of Rubisco content in conditions of elevated CO2 concentration. It seems the course of activities and content depending on age of the needles are antiparallel, that means that decrease of content is followed by increase of activity.
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Impact of elevated concentration of carbon dioxide on diurnal changes of Rubisco activity and its content
Zítková, Jana ; Vítová, Eva (referee) ; Hrstka, Miroslav (advisor)
Diurnal changes of initial and total activity and content of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) under conditions of ambient (350 µmol mol-1) and elevated (E = 700 µmol mol 1) concentration CO2 were measured in needles of Norway spruce. Needles of Norway spruce were taken on 22th July in two-hours from 3:30 a. m. till 10:30 p. m. The Rubisco activity was determined by spectrophotometry, the Rubisco content was detected by SDS-PAGE. The Rubisco activity was in most samples statistically significantly lower in needles cutlivated under ambient carbon dioxide then in needles cultivated under elevated carbon dioxide. Diagrams of the Rubisco activity shows absence of night inhibitor CA1P. The Rubisco activity was directly proportional to the intensity of photosynthetically active radiation in time from 7:00 a. m. till 7:30 p. m. The Rubisco content was statistically significantly higher in needles of Norway spruce cultivated under ambient carbon dioxide than in needles cultivated under elevated CO2, which shows acclimation of the Rubisco content during long-term effect of elevated CO2 concentration.
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The changes of Rubisco amount in Norway spruce grown at gradient of altitudes
Tomasz, Teresa ; Vítová, Eva (referee) ; Hrstka, Miroslav (advisor)
The study deals with differences of Rubisco enzyme content in Norway spruce needles (Picea abies L.) growing at different altitudes, thus at different concentrations of carbon dioxide. The collection of samples was performed in Jeseníky by Global Change Research Centre, Academy of Sciences of the Czech Republic. The samples of exposed and shaded needles were collected from 39 spruce trees in three altitudes – low (L), medium (M) and high (H). To separate Rubisco enzyme, the SDS-PAGE method was used, the content od Rubisco was determined by computer densitometry. The results of exposed needles confirmed that Rubisco content decreases with increasing altitude, however, in the case of shaded needles, there was no proof of a significant influence of altitudes on Rubisco enzyme amount. At low altitude, Rubisco content was significantly higher in exposed needles in comparison with shaded needles. At medium and high altitude no significant difference was detected between exposed and shaded needles.
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Analýza tahové-tlakové asymetrie u koeficientů příčné deformace pomocí metody korelace digitálního obrazu
Zadina, Jan
This thesis deals with the analysis of tensile-compressive asymmetry in the coefficients of transverse deformation (Poisson's ratios) of spruce wood (Picea abies L. Karst) in all three principal directions of growth, i.e. for the complete set of 6 Poisson's ratios. Tensile and compressive stress within one direction was applied to the same test specimen, and the digital image correlation (DIC) method was used to analyze surface deformations. For this purpose, the surface of the test specimens in two adjacent planes was recorded by cameras during mechanical loading, and the deformations were fully evaluated from the digital images, from which the Poisson's ratios were subsequently calculated. The evaluation of Poisson's ratios was performed using statistical tests. Statistical t-tests were performed to test the equality of means to compare the tensile and compressive Poisson's ratios, which showed differences between the compressive and tensile Poisson's ratios only in some cases. A one-way ANOVA and Scheffé's test were also performed to compare the different directions with each other, which showed a distribution of large and small Poisson's ratios mainly in tension. A regression analysis was also performed to determine the degree of correlation between the tensile and compressive Poisson's ratios, and correlation was demonstrated in the radial and tangential directions. Regression analysis was also performed to examine the relationship with wood density, which showed a slight correlation with some of the Poisson's ratios.
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Posouzení účinnosti stromových mikroinjektáží jako metody aplikace navnaděných stojících otrávených lapáků na LZ Boubín
Řezník, Pavel
The topis of this thesis was to evaluate the effectiveness of tree microinjection as a method of forest protection management. The evaluated data were following:maternal and larval corridors lengths of Ips typographus and mortality of I. typographus on treated and control trees in photoeleclectors . Data collected during the field experiments were statistically tested for the presence of differences using non-parametric analysis of variance (Kruskal-Wallis, resp. Dunn's t-test). The secondary aim of this thesis was to assess the use of the method as a poisoned standing baited trap in forestry practice in the Klet' forest area belonging to the Boubín Forestry Plant (Lesy České republiky, s. p.). Both measurements of the length of maternity and larval tunnels and the amount of beetles captured from photoeleclectors showed significant effectivity on reducing of I. typographus development and increased mortality pressure for spruce bark beetle adults.
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Srovnání citlivosti letokruhových řad jedle bělokoré (Abies alba) a smrku ztepilého (Picea abies) vůči klimatickým parametrům
Jakubcová, Vanda
The presented thesis deals with tree ring research of the Norway spruce (Picea abies) and the European silver fir (Abies Alba) in the area of Czech State Forest (Janovice – organizational unit). The goal of the study was to create as long chronologies as possible from living trees of Norway spruce and European silver fir and compare the sensitivity of radial growth to climate parameters (average monthly/seasonal temperatures and average monthly/seasonal precipitation) between these two woody plant species. Tree cores were sampled by using Pressler borer from the selected individuals of studied tree species. The data were processed by standard dendrochronological approaches (e.g. visual and statistical synchronization, cross-dating, age-trend standardization, climate-growth response analysis). The analysis of climate-growth responses showed that high temperatures in the spring and low temperatures with available precipitation in June are key for radial growth of Norway spruce in studied site. In contrast, European silver fir showed a higher sensitivity to precipitation before the beginning of the growing season (February) and in summer (July). Both European silver fir and Norway spruce showed increasing sensitivity to high temperatures and precipitation since 1980.
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Využití potenciálu přirozené a kombinované obnovy na Lesní správě Nasavrky (Lesy České republiky s.p.)
Zemanová, Anna
The diploma thesis dealt with the topic of the vegetation decline of the Norway spruce and its following regeneration in the Lichnice district, Nasavrky Forest Administration. From the results obtained from the forest economic records, it was found that the beginning of spruce decline was detected in 2018. The highest reported volume of random logging was reported in 2020 (46 405.92 m3). The largest reported clearing was also in 2020, at 53.69 hectares. The most common tree species in natural regeneration and artificial regeneration was Norway spruce, but its share is gradually decreasing year by year, to the benefit of a greater diversity of tree species on the range. Next, an experiment was conducted with the seedlings of the forest tree species that were collected and replanted as an underplanting in spruce stand 326A08. The mortality of the three study areas was evaluated here. The best results were achieved by white fir seedlings, where minimal mortality was found, on the other hand, the worst results were achieved by summer oak seedlings, where mortality was almost the majority.
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