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Fyziologické, anatomické a morfologické reakce sazenic buku lesního a smrku ztepilého na stres suchem a následnou závlahu =: Physiological, anatomical and morphological response of European beech and Norway spruce seedlings on drought stress and subsequent irrigation /
Hájíčková, Martina
European beech (Fagus sylvatica L.) and Norway spruce (Picea abies (L.) Karst) are the most abundant deciduous and coniferous tree species in the Czech Republic. Both beech and spruce are due to their sensitivity to drought threatened by ongoing climate change that can cause deterioration of their vitality in current habitats. Drought periods are already becoming longer and stronger and previously rare spring droughts become more frequent. The dissertation thesis is based on experiments with Norway spruce and European beech seedling exposed to different levels of drought (well-watered, moderate drought and severe drought). After three to six weeks of drought, the seedlings were well-watered for another two weeks and their response of physiology, anatomy and morphology was evaluated. Experiments were conducted with seedlings at early stage of leaf development and with fully developer leaves to compare response to spring and summer drought. Overall drought response was stronger in spring. Both spring and summer drought reduced gas exchange parameters (in both beech and spruce seedlings up to 100 %), hydraulic conductivity and less strongly also fluorometric parameters. Efficiency of water use in stressed seedlings decreased in spring, while it increased in summer. Shoot and leaves biomass was more reduced by drought than root biomass. Tree-ring width decreased about two times more in beech seedlings than in spruce seedlings. Vessel and tracheids in stem and shoots reduced their number and size, on the contrary, vessel size increased in beech petioles. After rewatering the reduced parameters increased, however, hydraulic conductivity, anatomy and morphology did not reach values of well-watered seedlings. While most of physiological parameters restored in moderately stressed seedlings, in severely stressed seedlings mainly gas exchange parameters remained lower.
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Vliv lesa na migraci a sedimentaci rizikových prvků a vybrané environmentální problémy
Juřička, David
The research of the dissertation thesis was focused on the ability of forests to activate and immobilize metals in the environment with their huge grants from deep mining of mineral resources. The research was be located in the area of Rožná with ongoing uranium mining, and area of Olší with ended uranium mining in the Czech Republic. During the years 2014 and 2015 was at the alluvial streams of Nedvědička (Rožná) and Hadůvka (Olší) recipients of pollution by radionuclides and metals from mining, taken in spring and autumn aspect of the overall 380 samples of leaves from trees, herb layer and river sediments. The samples were analyzed by the XFR and ICP-OES methods. In the organic matter were found such as elements Al, Cl, Cu, Cr, Fe, Mn, Mo, Ni, Rb, S, Sr, U, Zn and Zr, in many cases at high concentrations corresponding to polluted areas in the mining or industrial areas. A statistically significant difference in the concentrations of chemical elements in the fytomasss and river sediment between the upper, middle and lower stream areas of interest was not found. In the area of Nedvědička were found higher concentrations of a greater range of metals than in the area of Hadůvka. In the area of Hadůvka were by ICP-OES found significantly higher levels of uranium in the leaves than in the area of Nedvědička, reaching up to 34.86 mg.kg-1 in the dried material.The seasonal dynamics of the content of chemical elements in fytomass was confirmed. The species composition of the forest growth in the areas of interest with a predominance of Picea abies and the type of management has been evaluated as unfavorable for immobilization of metals in the environment. In the area of Nedvědička were suggested corrective actions - planting vegetation with a predominance of Fagus silvatica which should have a beneficial effect on soil and water pH by a suitable character of waste and contribute to the spread of inhibition of metals in the environment. In the area of Hadůvka are the suggested measures focused on the redevelopment of existing vegetation with a predominance of Picea abies on vegetation with a predominance of deciduous trees, especially Fagus silvatica, in order to adjust gradually the pH of the soil and thereby reduce the mobility of metals in the environment.
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MICROCLIMATIC INFLUENCES ON WOOD PHENOLOGY OF TREES AND SHRUBS IN TREELINE ECOTONE
Hejda, Tomáš ; Treml, Václav (advisor) ; Chuman, Tomáš (referee)
This thesis deals with the influence of microclimatic conditions (air temperature near tree/shrub top, temperature of the stem and root zone) on the wood phenology of trees (Picea abies) and shrubs (Pinus mugo) growing on the same site in the alpine tree line (ATL) ecotone. Phenological and microclimatic research was carried out in the Giant Mountains at 1,370 m a. s. l. in the 2017 vegetation period, with the aim to compare the course of wood formation depending on the microclimate, to determine the temperature thresholds of wood growth and differences in the morphology of trees and shrubs. Based on the microclimate analysis of trees and shrubs, individual variables were determined (average, average minimum, average maximum, daily amplitude of air, stem and root zone temperatures) characterizing the growing season. The collection of micro-drills of trees and shrubs took place from April to October in an interval of 6 - 11 days, which were subsequently processed and examined in the laboratory. The following phenophases of wood development were distinguished: cambial, enlarging, wall-thickening, mature cells and cells of the previous ring. Subsequently, differences in the number of cells of individual phenophases were identified between trees and shrubs. Furthermore, the temperature thresholds for...
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Seasonal growth dynamic of norway spruce at the study site of Rájec (Drahanská vrchovina Highland)
Chekuimo Tagne, Georges Herbert
Evaluation of the circumference increment of Norway spruce focused on the effect of inter-tree competition in the mature spruce stand was made at the study site of Rájec (Drahanská vrchovina Highland) over a 5-year period. Data were collected from 49 trees, which were monitored continuously with mechanical band dendrometers from 2010 to 2014. The dependency of the circumference increment on competition index, diameter at breast height, Lang's rain factor, mean temperature of various periods and sum of precipitation of various periods was evaluated. Climatic conditions of the study site are characterised with warm and wet summers and cold-dry winters. In 5 years average around 61 % of the annual precipitation falls during growing season. There was highly significant correlation between relative increment and temperature (p=2.324e-13) and significant correlation between relative increment and precipitation (p=0.0439). The performed results confirmed that inter-tree competition and diameter at breast height are sufficient variables for circumference increment estimation of unmeasured trees in the particular year. Coefficient of determination reached 0.25 - 0.63 for competition and 0.40 - 0.84 for tree diameter at breast height. The present investigation brings important results about tree growth and seasonal growth dynamics and its relation with competition and microclimatic conditions in mature spruce stand. It is obvious that unsuitable climatic conditions for spruce can lead to stem shrinkage during growing season. Here we assume that these responses are caused mostly by water storage deficit in stem and this leads to decreasing of the tree vitality. Such phenomenon will have significantly negative ecological and economic consequences in expected climatic changes in the future.
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The role of DSE (Dark Septate Endophytes) in plant communities in forest ecosystem
Lukešová, Tereza
10 Abstract All plants live in symbiosis with fungal endophytes - they can form mutualistic, commensal or parasitic symbioses. Symbiosis of root endophytes, called for their darkly pigmented and septated hyphae dark septate endophytes (DSE), and plants has been often overlooked although its role for plant communities can be very important. Despite their ubiquitous presence in roots of terrestrial and also aquatic plants the influence of DSE on their host plants is still unresolved. Results of previous studies are inconsistent - some reported that DSE have positive effects on their host plant growth and some negative. The main reason for this inconsistency might be their complicated taxonomy and difficult identification of different cryptic species which are morphologically indistinguishable. We were able to complete a unique collection of the most common DSE species, mainly members of the Phialocephala fortinii - Acephala applanata species complex. The collection includes the most common DSE species isolated from roots of forest plant communities. The goal of my thesis was to describe behaviour of DSE in roots of typical forest plants and elucidate their physiological influence on host plants. In vitro resynthesis experiments were used to observe root colonization patterns. Nutrient flow between the plant...
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Klimatický signál v letokruhových chronologiích borovice kleče
Samusevich, Alina ; Treml, Václav (advisor) ; Vejpustková, Monika (referee)
Pinus mugo Turra (sensu lato) is a prostrate shrub growing above the alpine timberline in the mountain ranges of Southern, Central and Eastern Europe. It is well adapted to the harsh alpine environment creating different mechanisms for survival. The research was carried out in Krkonoše Mountains on base of Pinus mugo individuals compared with Picea abies trees. Samples from shrubs were gathered using serial sectioning from four sites in different elevations located on Sněžka Mountain and Smogornia Ridge. Further analysis of the sampled material was made with the help of different detrending methods to see which method will return the best growth response to climate parameters. RCS detrending and detrending via simple averaging reflected the best climate signal contained in dwarf pine chronologies. The advantage of these methods is based on their ability to reflect growth conditions of the particular site. Upper sites showed significant correlations with temperatures of the growing season, while on lower sites the signal was quite unclear. The amount of precipitation plays the significant role on shrub growth during the vegetation period (especially July month) and early spring when water is very important for growth initiation. Upper Pinus mugo sites showed high sensitivity to droughts, especially...
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The role of DSE (Dark Septate Endophytes) in plant communities in forest ecosystem
Lukešová, Tereza ; Vohník, Martin (advisor) ; Mrnka, Libor (referee)
10 Abstract All plants live in symbiosis with fungal endophytes - they can form mutualistic, commensal or parasitic symbioses. Symbiosis of root endophytes, called for their darkly pigmented and septated hyphae dark septate endophytes (DSE), and plants has been often overlooked although its role for plant communities can be very important. Despite their ubiquitous presence in roots of terrestrial and also aquatic plants the influence of DSE on their host plants is still unresolved. Results of previous studies are inconsistent - some reported that DSE have positive effects on their host plant growth and some negative. The main reason for this inconsistency might be their complicated taxonomy and difficult identification of different cryptic species which are morphologically indistinguishable. We were able to complete a unique collection of the most common DSE species, mainly members of the Phialocephala fortinii - Acephala applanata species complex. The collection includes the most common DSE species isolated from roots of forest plant communities. The goal of my thesis was to describe behaviour of DSE in roots of typical forest plants and elucidate their physiological influence on host plants. In vitro resynthesis experiments were used to observe root colonization patterns. Nutrient flow between the plant...
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Charakterizace společenstva hub, podílejícího se na rozkladu opadu v jehličnatých lesích Národního parku Šumava
Žifčáková, Lucia ; Baldrian, Petr (advisor) ; Schierová, Michaela (referee)
Understanding of carbon cycling in coniferous forests that represent a large carbon sink is crucial for our understanding of natural processes under global climate change. Recognition of fungi as fundamental decomposers can contribute to this understanding. Fungi are able to decompose numbers of substrates and possess a variety of enzymes to do so In this study I present litter decomposing fungi in mountain spruce forest from national park Šumava. The aim of my thesis was to follow succession and community changes of fungi from the early stages of decomposition of Picea abies needles until degradation of organic matter in the organic horizon of the soil. This aim was accomplished partly by recording the extracellular enzyme production of fungi in different stages of decomposition from needles attached to the twigs of a fallen tree to a litter material in later stages of decomposition on the soil surface. In addition to testing of fungi on their natural substrata - needle litter, enzyme activities were also measured in laboratory agar cultures, which allow comparison of diverse fungi with different origins. Enzyme activities were aimed at enzymes decomposing cellulose and compounds found in litter. Although ecology of endophytic and saprothrophic fungi suggest differences in enzyme production, these...
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Fungi associated with tree roots
Charvátová, Markéta ; Baldrian, Petr (advisor) ; Gryndler, Milan (referee)
In contrast to the bulk soil environment, plant roots represent a habitat with higher nutrient availability due to the supply of photosynthesis-derived C-containing compounds. The roots thus support the life of various microorganisms that use such compounds, but the root-associated microbes in the same time may face a limitation in N and P availability. Unlike bacteria, many filamentous fungi are able to transport these compounds from soil and their mycelia thus typically extend into this environment. Ectomycorrhizal fungi are a typical example of this nutrition strategy. Tree roots produce exudates, that differ in thein composition for each species and they can also differ among individuals. It causes a high diversity of root-associated fungi. Soil is also inhabited by parasitic and saprotrophic fungi. Composition and activity of microbial communisies in the rhizosphere differ from the bulk soil. This work points at the differences of the rhizosphere and builk soil, the importance mycorrhizal fungi and it presents an overview of fungal species that have been found on the roots of spruce - Picea abies. Key words: fungi, mycorrhiza, soil, rhizosphere, Picea abies
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Natural regeneration of spruce stands in Vysoké Tatry (High Tatras) after large scale disturbation
Michalová, Zuzana ; Weiser, Martin (advisor) ; Wild, Jan (referee)
The observational study on natural regeneration of Norway spruce (Picea abies) was provided during seasons 2010 and 2011 in the windthrow area of High Tatra National Park. The main aim of this master thesis was to describe the distribution pattern in Norway spruce regeneration as well as to estimate the spatial scale, which most preciselly describes the differences in its phenotypic variability. Following step was to determine the relative influence of abiotic and stand factors on the growth characteristics and abundance of spruce seedlings. The Main focus lied on stressing the role of biotic interactions, like intraspecific and interspecific competition, leading to certain discrepancies in the phenotype, as well as in abundance of spruce seedlings.The reponse in variability in spruce traits was recognized at each spatial level. The results showed clear causality between soil moisture and vegetation composition, which both directly modified not only the phenotype of spruce seedlings and plants, but have even influenced their counts on particular stands.
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