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Carbon Stable Isotopes in Spruce Tree Rings as a Marker of Pathogenic Fungal Attack of Trees.
NECUDOVÁ, Lucie
Trees are long living plants, which use carbon from the air and hydrogen and oxygen predominantly from soil water for their growth. They deposit these elements largely into a wood where they may persist for thousands of years. Tree growth is influenced by environment, especially by air temperature and precipitation. These factors have an effect on stomatal conductance and photosynthesis rate which influence carbon stable isotope ratio (13C/12C) in the tree tissue. This thesis is focus on stable carbon isotopes in tree-rings of Norway spruce attacked by honey mushroom, and Norway spruce which doesn?t show any signs of disease. The hypothesis of the thesis is based on an expected difference in carbon isotope fractionation during photosynthesis between the spruce attacked by honey mushroom and a ?healthy? spruce. The difference in isotope fractionation could be caused by water deficit induced by honey mushroom disease in the tree. We expect that the attacked spruce defends against water loss by closing stomata, and it could lead to lower CO2 concentration in the needles and higher ?13C value in tree-rings biomass The stable carbon isotope analysis (IRMS) was done on tree-rings of four spruce pairs, each one including an attacked spruce and spruce which didn?t show any signs of disease. Carbon isotope ratio of early wood, late wood and in biomass of the whole annual increment was measured. In contrary to our hypothesis we did not fined any systematic difference in isotopic composition between the attacked spruce and the spruce which did not show any signs of disease.
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The role of wood decay fungi in the dynamics of a mountain spruce forest
POUSKA, Václav
This thesis is focused on environmental preferences of wood-decaying fungi and their relationships with forest structure and development. Relationships of fungi to properties of wood and forest stands were studied on the basis of field observations in Central-European mountain spruce forests. Plot-based approach was used to reveal a general pattern in the diversity of fungi within a single forest stand and between different stands. The analysis of stand structure provided a background for plot-based approach. Substrate-based approach was used to study single species preferences and their communities. In addition, the influence of wood properties (including fungi and their rots) on the regeneration of spruce on logs was studied.
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Site conditions influence on natural regeneration of Norway spruce forests in the Šumava Mts.
ČERMÁK, Martin
The main aim of my thesis was to evaluate natural regeneration status of Norway spruce forest stands on three research plots with different forest managment after windstorm disturbance in January 2007. In addition, an evaluation of micro-site conditions influence on germination and surviving of spruce seedlings and shade effects.Research work was carried out on the Černá hora Mt. in the Šumava Mts. from August to October 2008.
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Site conditions effect on Norway spruce natural regeneration after windthrow on the Černá hora Mts. (National Park Šumava)
ČERMÁK, Martin
The main aim of my thesis was to evaluate natural regeneration status of Norway spruce on three research plots with different forest managment after windstorm disturbance in January 2007. In addition, evaluation of micro-site conditions and shade effects on germination and surviving of spruce seedlings and assessment of crown conditions in forest research plot was performed. Research work was carried out on the Černá hora Mt. in the Šumava Mts. in 2009 - 2010. Obtained results could provide information to help to decide the choice of management of forest stands after disturbance in protected areas.
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Risk ratingo of break up forest stands with dominance norway spruce by the impact of abiotic and biotic stressors in the Štěkeň district.
STRNADOVÁ, Marta
The aim of the work was to evaluate present health status and to estimate the environmental risk of Norway spruce forest stands destabilization in forest area Brdo, belonging to the forest district Štěkeň. The methods of retrospective analysis, using ground observation of defoliation and crown structure transformation and field survey of present impact of abiotic and biotic stressors on Norway spruce, were used on the research plots. In addition, the data processing of the volume of incidental felling using multi-dimensional statistical method in the programme Canoco was carried out. Information from this work could contribute to the forest management adjustments in the Štěkeň district, minimizing the environmental stressor impacts.
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Influence of the light conditions on herbaceous layer in mountain spruce forests in the Giant Mountains using GIS
ČIHÁK, Jan
Mountain forests are an important part of the landscape in our country. In the last three decades they have been seriously damaged by anthropogenic influence, especially immissions. The immissions make worse the health status of Norway spruce (Picea abies) forests, which cause changes in a structure of herbaceous layer, in which the health status of forest stand is reflected. The main goals of my work were to map the cover of herbaceous and mossy layers in two permanent research plots in the Giant Mountains ( Alžbětinka, Modrý důl), to create maps of herbaceous cover, to digitize them and to compare these maps with the extent in years 1993-1994 using a developing analysis in GIS and to detect influence of light conditions on herbaceous layer. Using digitizing and static evaluation of prepared detailed vegetation maps of the both permanent research plots, some important changes were found out in dominant soil cover categories. In the first research plot Alžbětinka, decline of the grass Calamagrostis villosa and increasing of Vaccinium myrtillus cover were evident. In the second research plot Modrý důl, decline of both investigated species, Avenella flexuosa and Calamagrostis villosa, was observed. Another goal of my research was to detect influence of the light conditions on herbaceous layer and nature regeneration of the Norway spruce on permanent research plot Modrý důl. Dependence of the basic categories of the soil cover on the percentual ratio of the light gaps in the crown canopy was proved. Dependence of the height of the seedlings on the ratio of the light gaps was also tested but it was not statistically proved. The negative dependence of survival on the ratio of the light gaps of the seedlings germinated in 1996 was proved, but not of the seedlings germinated in 2004.
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Relationship between \kur{Ips typographus} outbreak and Norway spruce ecosystem status in the Černá hora Mt. and Smrčina Mt. (Šumava National Park)
VAČKÁŘOVÁ, Tereza
The aim of the thesis was to find out whether there is a relation between spruce-bark beetle infestation and health condition of spruce stands. The field work was conducted in Šumava National Park on two research plots ? Černá Hora and Smrčina. In order to determine the health condition of spruce stands the methodology according to Cudlín et al. (2001) was used. The emphasis was put mainly on monitoring the percentage of individual parts of tree crowns, total defoliation, defoliation of primary structure and percentage of secondary shoots. According to the parameters the rate of crown structure transformation was identified and the trees were classified into four stress categories. All the monitored research plots, founded in spring 2009, with an exception of plot ?B? in Černá hora, were infested with a spruce-bark beetle. Only a single tree infested in 2009 was identified in plot ?C?. The methodology according to Jakuš et al. (2009 and 2010) was used to periodically monitor spruce-bark beetle invasion and individual reaction phases of the spruce stands. Furthermore, according to the data obtained a layer of tree occurrence in various stages of bark beetle infestation was constructed in GIS platform using ArcView 9.3 programme. It enabled us to determine the degree into which the bark beetle infestation and consequent colonization of surrounding trees is dependent upon the trees´ mutual position and their crown conditions. A hypothesis that a spruce-bark beetle prefers trees with a more transformed crown structure (Moravec at al. 2002) was proved only on the plots in Smrčina. The thesis should contribute to the study of mutual dependence between bark beetle infestation and spruce stands health condition as well as to their development in reaction to such infestation.
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