National Repository of Grey Literature 18 records found  1 - 10next  jump to record: Search took 0.01 seconds. 
Vliv rozsahu kolonizace kořenového systému vějířovcem obrovským na stabilitu stromů
Cvach, Marek
This thesis investigates the effect of the extent of colonization of the root system of Meripilus giganteus on the stability of Fagus sylvatica. On the basis of pulling tests of infested trees from the Czech Republic, the Netherlands and Belgium and their accompanying photo-documentation, data were evaluated and used to establish relationships between the effects of different factors on the resistance of trees to uprooting. Graphs were produced for each of the dependencies, which were subsequently evaluated and commented on verbally. For example, a high dependence of the resistance to uprooting was found for the proportion of trunk diameter and the angle of colonisation of M. giganteus around the tree, and for the different effects of each parameter.
Biodiverzita dřevních hub v Arboretu Křtiny (Školní lesní podnik Masarykův les Křtiny)
Kotyz, Lukáš
The bachelor thesis focuses on the biodiversity of wood fungi in Arboretum Křtiny. Monitoring of the area started in February 2021, last visit was in January 2022. During this time 15 field trips were done in total. Overall 118 wood fungi were found in the arboretum. Of these, 10 species are in the Red list of fungi of the Czech Republic. Most of the species were found in October of 2021 (97), the least in May and June of 2021 (39). From the total number of macromycetes found, 88 % were basidiomycetes and 12 % ascomycetes. Most of the fungi species grew on Fagus sylvatica (77) and a total of 32 species were found on Salix ssp. White wood decay was noted in more than 90 % fungi species. 93 species were saprotrophic, 21 saproparasitic and 4 parasitic. More than 60 % of fungal species were present in the middle phase of wood decomposition. Over 1/3 of mushrooms preferred the 3rd degree of wood thickness (11–30 cm) and the 3rd degree of bark preservation. The rarest fungi found is Vararia investiens. The most commonly found species were: Fomes fomentarius s. l., Phellinus igniarius, Trametes suaveolens, Hypoxylon fragiforme, Kretzschmaria deusta, Xylodon flaviporus, Bjerkandera adusta, Ceriporiopsis gilvescens, Jackrogersella cohaerens, Eutypa spinosa and Biscogniauxia nummularia.
Růstová odezva dřevin středoevropského temperátního lesa na disturbanční událost =: The growth response of Central European temperate forest trees to disturbance events /
Vašíčková, Ivana
The growth response of trees to disturbance events in 8 beech-dominated natural forests in Czech Republic was studied using standard tree-ring analysis. With the use of circa 2 000 increment cores a disturbance regime of Žofín old-growth forest was reconstructed. The results indicate not only disturbance intensity, but also their spatial characteristics determine the effect of disturbance on further forest ecosystem development. As the picture of past disturbances had not emerged to be sufficient enough to describe a historical forest development, recognizing the statistical error of their reconstructions was of great importance. Thus, the following studies focused on quantification of uncertainty in detecting the disturbance history using dendrochronology. Uncertainty in determination of summary disturbance history within the whole stand as well as disturbance spatial patterns were evaluated. The results uncovered that the specific character of dendrochronological data, i.e. the different reactions of individual trees to the identical disturbance event, was a significant source of this uncertainty. The follow-up study logically concerned on examination the true response of Fagus sylvatica to disturbances, dated by independent dendrometric and photogrammetric datasets. On the basis of analysis of nearly 300 tree responses, new empirically-derived criteria for dendrochronological determination of tree growth response were suggested. Finally, factors controlling growth response of Fagus sylvatica to disturbance events were addressed. Regression analysis determined complex of diverse factors of different spatial levels driving the growth reaction following canopy opening.
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.
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.
Využití extraktivních látek tropických dřev pro zvýšení přirozené trvanlivosti buku
Přibylová, Zdeňka
This Bachelor thesis focuses on evaluating antimycotic activity of extractive compounds acquired using the FexIKA extraction apparatus. Merbau (Intsia bijuga O.Ktze.) and jatoba (Hymenaea courbaril L.) were used as the sampled material. The extractive compounds were obtained from ground samples of the tropical woods. Then, the beech wood was impregnated with the compounds. A rapid durability test of vulnerability against Trametes versicolor L. was performed. From the data acquired, the weight loss of the impregnated samples and reference samples was evaluated. The results show that the extractive compounds procured from Merbau wood in the highest concentration were able to increase the natural durability of beech from class 5, i.e. not durable, to class 1 - very durable. Impregnation with extractives from Jatoba in the highest concentration level increased the durability from class 5 to class 2, i.e. durable.
SMV-2016-736: Reaction of plants to presence of CdO nanoparticles in air
Večeřa, Zbyněk
Study of the impact of elevated concentrations of nanoparticles of cadmium oxide in the air on Cd content in coniferous Norway spruce (Picea abies) and deciduous beech (Fagus sylvatica). Estimation of the sensitivity of urban forests and woody species to the effects of abiotic stresses and extreme climatic events.
Demography and Dispersal Ability of a Threatened Saproxylic Beetle: A Mark- Recapture Study of the Rosalia Longicorn (Rosalia alpina)
DRAG, Lukáš
This thesis focuses on demography and mobility of an endangered and strictly protected icon of European saproxylic biodiversity, the Rosalia longicorn beetle (Rosalia alpina). Using the mark-recapture method we estimated the size of the population, adult longevity, and dispersal ability of the Rosalia longicorn on three hills in the Ralska Upland, Czech Republic. Furthermore, we assessed the distribution pattern of another 15 populations inhabiting small patches of old beech forest in this area. Factors affecting local survival and the species conservation are discussed.
Phylogeography and conservation genetics of endangered saproxylic beetles in Europe
DRAG, Lukáš
This thesis introduces the use of molecular methods for the conservation of several species of endangered saproxylic beetles in Europe. It focuses on the questions related to the DNA preservation and microsatellites development, as well as the evolutionary history and conservation of threatened species. Using the combination of mitochondrial and nuclear markers, the genetic diversity and reintroduction history of Cerambyx cerdo was assessed and the phylogeography of Rosalia alpina from the whole range of its distribution was studied. This information is valuable for designing more efficient conservation strategies.
Evaluation of FGMRI provenance plot with European beech (Fagus sylvatica L.) on the locality Jíloviště, Baně (Central Bohemia)
Kuklová, Alena ; Podrázský, Vilém (advisor)
Buk lesní (Fagus sylvatica L.) je nejvýznamnější listnatou dřevinou České republiky. V minulých letech se jeho zastoupení velmi snížilo v důsledku nešetrné těžby, přírodních disturbancí a následně hlavně změnou lesního hospodaření, kdy se upřednostňovaly především jehličnaté dřeviny smrk ztepilý (Picea abies) a borovice lesní (Pinus sylvestris). Provenienční výzkum se, díky jejich preferování při pěstování, nejprve věnoval hlavně jehličnatým dřevinám, až v pozdější době se zaměřuje i na dřeviny listnaté. V současné době se naše lesní hospodářství k buku znovu vrací a jeho zastoupení se v našich lesích pomalu opět zvyšuje. Úkolem diplomové práce je provedení terénního šetření na provenienční výzkumné ploše VÚLHM Strnady č. 82 Jíloviště, Baně ve věku 34 let (zjištění počtu rostoucích jedinců, tloušťkového a výškového růstu, tvárnosti kmene, větvení, úhlu větví, tloušťky větví), zjištěná a naměřená data statisticky zpracovat a vyhodnotit rozdíly mezi testovanými proveniencemi buku lesního. V první části práce je zpracována literární rešerše, zaměřena na provenienční výzkum buku lesního, v další části jsou statisticky zpracovány kvantitativní a kvalitativní znaky zjišťované na výzkumné ploše. V poslední části jsou vyhodnocená data porovnávána s daty z minulých let.

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