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The influence of climate on the radial growth of Scots pine in the northern Scandinavia
Tomeš, Miroslav ; Treml, Václav (advisor) ; Šefrna, Luděk (referee)
The presented master's thesis deals with the influence of climate on the radial growth of Scots pine in the northern Scandinavia. Trees growing at the polar treeline are sensitive to environmental changes, and therefore their wood is used to study growth responses to ongoing climate change. During the period of the 20th and the beginning of the 21st century, air temperatures and precipitation sums were correlated with tree rings and dendroanatomical data of Scots pine from northern Finland. It was found that the widths of the tree rings had a slightly increasing trend during the observed period. Within the framework of the correlation relations, the controlling influence of the air temperatures of the current July on annual increments was confirmed. Thanks to the higher temperatures of the summer season, wider tree rings were formed. In addition, May and summer precipitation have been shown to be important for the final width of the tree ring. The currently often discussed problem of decoupling the tree ring chronology curve from rising summer temperatures ("divergence problem") was not clearly observed in this work. In order to evaluate the dendroanatomical parameters, the tree rings of the studied individual were divided into four sectors with a similar number of cells in the radial file. During...
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Ecological trends in xylem production of woody plants
Tichý, Jan ; Treml, Václav (advisor) ; Schnablová, Renata (referee)
Xylogenesis (wood formation) is one of the most important biological processes on Earth. Woody plants store atmospheric carbon during this process and are thus an essential player in the carbon cycle, and therefore in the interactions of the biosphere and the Earth's climate system. The course of xylogenesis is affected by many factors, the main factors include photoperiod, temperature and water availability. The significance and impact of individual factors on xylogenesis changes with time and place on Earth. The cambium, which by its division forms wood, enters the dormant and active phase during the year. As part of the changes in the activity of the cambium, rings are formed from which it is possible to read the conditions in which the tree was located during the formation of the given tree ring. This characteristic feature of wood is the subject of many studies and can be used to investigate the effects of climate change on xylogenesis.
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Analýza variability tvorby xylému po obvodu kmene smrku ztepilého v rámci vegetačního období
Kašpar, Miroslav
Kašpar, M.: Analysis of the variability of xylene formation along the circumference of the spruce tree (Picea abies L.) during the vegetation period. Bachelor thesis. Mendel University in Brno. 2016 The bachelor thesis is focused on the analysis of the variability of xylum formation along the circumference of spruce stem in the vegetation period. Research on xylogenetic variability was carried out on the research area in Rájci-Němčice. The main task is to compare the variability of xylan production in the same old trees during the 2016 growing season. Sampling was performed at weekly intervals from 31 March to 10 November using trephor. From the collected microwells, continuous preparations were then made. The obtained data were compared with literary sources focused on similar issues.
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Analýza procesů xylogeneze a floemogeneze u jedinců smrku ztepilého (Picea abies (L.) Karst.) ve dvou vegetačních obdobích
Kašpar, Miroslav
KAŠPAR M.: Analysis of xylogenis and floemogenesis of Norway Spruce (Picea abies (L.) Karst.) during two growing seasons. The thesis deals is focused on finding and evaluating the creation of wood and phloem of Norway spruce during the vegetation period 2015 and 2016 at the reasearch area Rájec-Němčice. Six representative trees were selected on the surface and samples were taken periodically. Permanent microscopic slides were prepared and examined for the samples obtained. The activity of cambium, the different phases of differentiation of wood and bast elements and the rate of growth using Gompertz function were evaluated. The data collected for each year were compared with each other and compared with the results of other authors. Growth variations were noted within two growing seasons. Statistically significant differences were seen in the number of kambia cells, whether in dormancy or during the active period. There were statistically significant differences at the time of termination of the individual cell phases. The different values of the years also resulted from the results of the Gompertz function. Generally speaking, in 2016 the growth dynamics was more intense and the number of cells generated was higher than in the previous year.
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Analýza tvorby dřeva buku lesního na výzkumné ploše Rájec-Holíkov
Porvalík, Radim
This bachelor thesis presents xylem formation of common beech (Fagus sylvatica L.) on sample plot in Rájec-Holíkov in one year period,specifically exeptionally dry year 2015. Total of 6 trees were used as sample trees of which micro bores were obtained around the grith with the Trephor apparathus in chronological order from 23rd March to 12th November, once in a week. In laboratory, the samples were processed into permanent slides and analysed with a light microscope. The processes of xylem growth and xylem maturing from the initial phase to the complete differentiation were observed. First symthomps of initial phase and cambium activity occurred when mean day temperature reached 7,5 °C corresponding to end of April and start of the May. The secondary cell wall and gradual lignification occurred from 4th June 2015 (155 DOY) to 20th August 2015 (232 DOY). Fully lignified cells were occurring gradually until October. Total growth of tree ring lasted 90 days. The mean size of newly formed tree ring size 1235 µm according to Gompertz function.
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Vliv solární radiance na strukturu xylému jehlic smrku ztepilého
Bartoňová, Lenka
In this thesis is evaluated the xylem structure of Norway spruce needles depending on solar radiation and altitude. Same-age spruce stand has been selected on the area of Hruby Jesenik at different altitudes on the southern and northern exposure. Sun needle samples were taken on each stand. The analysis of xylem structure was done. The number of tracheids, tracheid diameter, tracheid area and xylem area were evaluated. It was found that more than 50% dependence of xylem parameters on altitude and solar radiation, where exposure significantly affects the xylem structure only at altitudes above 1 200 m. The prediction maps show that the highest values of predicted xylem parameter values are found between 800 m and 1200 m about sea level.
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