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Vyhodnocení fenologických fází dospělého bukového porostu na Ekosystémové stanici Štítná nad Vláří
Střecha, Jaroslav
At the Štítná nad Vláří Ecosystem station in the White Carpathians, phenology cameras have been taking pictures inside an adult beech forest from a meteorological mast, together with the collection of meteorological data since 1960. Phenology records regularly recurring changes in plants, the so-called phenophases, in relation to the external environment and especially the weather. Therefore, forest ecosystems function as an important bioindicator of climate change. From the phenologial observation in 2018–2020, beech phenophases were evaluated in two ways. Visual evaluation and analysis of the vegetation index from the phenology camera image. Image analyses record the phenological stage earlier than the observer. There was an increase in the average annual temperature, resulting in a longer growing season. The growing season was extended by up to 82 days. This trend of climate change, together with the occurrence of years with a lack of precipitation, will have a negative effect on the vitality of beech and forest ecosystems.
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How will a longer vegetative season affect carbon sequestration in plant biomass
Kasperová, Denisa ; Albrechtová, Jana (advisor) ; Ponert, Jan (referee)
As a result of human activity, a large number of greenhouse gases, especially CO2, is released into the atmosphere, which causes a greater greenhouse effect and an increase in the temperature of the surface of the planet and the air in the atmosphere. Ongoing climate change is one of the great challenges facing society, as rising temperatures on the planet greatly affect the functioning of its ecosystems. Extremes arising from climate change, especially temperature rise and lack of precipitation or a change in the annual distribution of precipitation, affect the physiology and phenology of plants. Higher temperatures cause plant growing seasons to shift and lengthen, which has a direct impact on the sequestration of carbon in plant biomass through a biochemical, physiological plant process called photosynthesis. The increase in CO2 concentration in the atmosphere is slowed down by terrestrial forest ecosystems, as they can retain carbon in their tissues, especially in wood, for a relatively long time before it returns to the atmosphere. However, the efficiency of binding carbon into biomass also depends on other physiological processes, e.g., photorespiration, breathing, gas exchange between the plant and the atmosphere. Stressors caused by climate change can then limit growth, photosynthesis,...
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Optical properties of the leaf in relation to its anatomical traits
Neuwirthová, Eva ; Albrechtová, Jana (advisor) ; Tomášková, Ivana (referee) ; Písek, Jan (referee)
Plant functional traits at the leaf level are commonly used to predict ecosystem responses to environmental factors and describe global climate change processes at the ecosystem level. Plant functional traits include both leaf biophysical traits (e.g., photosynthetic pigment content and water content) and structural traits (e.g., leaf thickness and proportion of photosynthetic and non-photosynthetic tissues). Leaf biophysical and structural traits can be detected either destructively in the laboratory or non-destructively using leaf optical properties. Although estimating chlorophyll content from leaf optical properties is a well-established methodology, the influence of leaf structure and internal anatomy on leaf optical properties has only been thoroughly studied in the last two decades. The papers included in my thesis and my thesis itself are mostly focused on the study of typical European deciduous trees of temperate and hemiboreal forests with leaves having a dorsiventral structure (i.e., the mesophyll is differentiated into palisade and spongy parenchyma). Furthermore, my thesis includes a study on the effect of leaf surface structural traits on optical properties. In this study, two groups of phylogenetically close herbs with comparable internal leaf structure were used (mutants of...
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Changes of length of periods with characteristic temperatures
Holtanová, Eva
Title: Changes of lengths of periods with characteristic air temperatures Author: Eva Černochová Department: Department of Meteorology and Environment Protection Supervisor: doc. RNDr. Jaroslava Kalvová, CSc. Supervisor's e-mail address: jaroslava.kalvova@mff.cuni.cz Abstract: Lengths of periods with characteristic air temperatures were derived using two different methods (linear interpolation, robust locally weighted regression) for 10 stations in the Czech Republic and for output data of regional climate models HIRHAM and RCAO in 4 grid points. Averages for a forty-year period (1961-2000) and for a thirty-year period (1961-1990) were computed as well as averages for every decade. Considerable attention was also paid to the analysis of methods used in the research. Most stations showed lengthening of growing season and summer during the twentieth century. Decennary average length of growing season and summer shortened in the years 1971-1980. The comparison of output data of regional climate models HIRHAM and RCAO and measured station data showed that the thirty-year average lengths of growing season and summer estimated by the two models were reasonably accurate approximately half of all cases. The models' estimates were not accurate at all concerning decennary averages. Keywords: robust locally...
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Characteristics of cultivar composition of lupine in the Czech Republic
VOKURKA, Ondřej
This work deals through the method of library research with the current state and options of lupines growing in the Czech Republic, with a closer look on their cultivar composition. Initial characterisation of the vast genus Lupinus and chapters about history, contemporary significance and utilisation of lupine are followed by detailed botanical description of cultural species of this genus. Special attention is given to the growing season, as it is a significant factor that influences the potential of lupines growing in the Czech Republic. The following chapters deal with necessary facts about the habitat requirements of particular lupine species and the agrotechnical principles followed when growing lupines. Then the particular species are examined according to their significance, botanical description and environmental demands. The research concludes with a sketch of the breeding trends and characterisation of the available cultivar composition, including description of lupine varieties currently registered in the Czech Republic.
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Changes of length of periods with characteristic temperatures
Holtanová, Eva
Title: Changes of lengths of periods with characteristic air temperatures Author: Eva Černochová Department: Department of Meteorology and Environment Protection Supervisor: doc. RNDr. Jaroslava Kalvová, CSc. Supervisor's e-mail address: jaroslava.kalvova@mff.cuni.cz Abstract: Lengths of periods with characteristic air temperatures were derived using two different methods (linear interpolation, robust locally weighted regression) for 10 stations in the Czech Republic and for output data of regional climate models HIRHAM and RCAO in 4 grid points. Averages for a forty-year period (1961-2000) and for a thirty-year period (1961-1990) were computed as well as averages for every decade. Considerable attention was also paid to the analysis of methods used in the research. Most stations showed lengthening of growing season and summer during the twentieth century. Decennary average length of growing season and summer shortened in the years 1971-1980. The comparison of output data of regional climate models HIRHAM and RCAO and measured station data showed that the thirty-year average lengths of growing season and summer estimated by the two models were reasonably accurate approximately half of all cases. The models' estimates were not accurate at all concerning decennary averages. Keywords: robust locally...
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Changes of length of periods with characteristic temperatures
Černochová, Eva ; Metelka, Ladislav (referee) ; Kalvová, Jaroslava (advisor)
Title: Changes of lengths of periods with characteristic air temperatures Author: Eva Černochová Department: Department of Meteorology and Environment Protection Supervisor: doc. RNDr. Jaroslava Kalvová, CSc. Supervisor's e-mail address: jaroslava.kalvova@mff.cuni.cz Abstract: Lengths of periods with characteristic air temperatures were derived using two different methods (linear interpolation, robust locally weighted regression) for 10 stations in the Czech Republic and for output data of regional climate models HIRHAM and RCAO in 4 grid points. Averages for a forty-year period (1961-2000) and for a thirty-year period (1961-1990) were computed as well as averages for every decade. Considerable attention was also paid to the analysis of methods used in the research. Most stations showed lengthening of growing season and summer during the twentieth century. Decennary average length of growing season and summer shortened in the years 1971-1980. The comparison of output data of regional climate models HIRHAM and RCAO and measured station data showed that the thirty-year average lengths of growing season and summer estimated by the two models were reasonably accurate approximately half of all cases. The models' estimates were not accurate at all concerning decennary averages. Keywords: robust locally...
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[Population ecology of annual hemiparasitic species \kur{Melampyrum pratense.}
PRŮŠOVÁ, Monika
The thesis deals with the hemiparasitic species Melampyrum pratense. This species was monitored during the growing season 2009 and the relationship between morphological characteristics and reproductive success of plant individuals was assessed. The relationships between population density, the vegetative biomass and the investments in generative reproduction were investigated. Identity of the host species was determined using the DNA barcoding method.
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