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Hodnocení zdravotního stavu smrku ztepilého ve středních a vyšších polohách České republiky s využitím habituální diagnostiky a letokruhových analýz
Žid, Tomáš
Tree vitality is one of the important indicators of forest condition (INNES, 1993). Because vitality cannot be measured directly, only appropriately defined indicators can be used to describe it (GEHRIG, 2004). In order to meet the objectives of this work, a detailed field evaluation of crowns of Norway spruce (Picea abies (L.) Karst.), called habitual tree diagnostics (based on CUDLÍN ET AL., 2001), and dendrochronological analysis were chosen. A total of 2 342 individuals of Norway spruce were evaluated during the years 2005 to 2015. The results of the work summarize the obtained field data according to the individual observed descriptive quantities of the evaluation of crowns, and also present the results of dendrochronological analysis. These data are further subjected to a statistical analysis of the acceptance or refutation of the stated hypotheses, including the confrontation of habitual diagnostics with the arithmetic averages of detrended widths of annual rings. The results showed that spruces had better vitality in water-affected locations, outside the southern exposure, and also at higher altitudes. However, recent years show that growing spruce outside its ecological optimum will no longer be possible and it is therefore necessary to look for new ways out of the current unprecedented calamity of spruce monocultures (HLÁSNÝ ET AL., 2021a), which was probably initiated by the predisposing effects of repeated and prolonged drought years (BÜNTGEN ET AL., 2021).
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Historical acid deposition as a predictor of current growth trends in montane forests in the Krkonoše Mts.
Procházková, Kateřina ; Tumajer, Jan (advisor) ; Vejpustková, Monika (referee)
This diploma thesis is focused on mountain Norway spruce (Picea abies) forests and their sensitivity to acid deposition, which culminated in Czechia during the 1980s. Acid deposition negativelly affects tree growth resulting in high mortality and poor health status of the entire forest stands. Mountain forests provide numerous important ecological services, which increses the need for understanding of the processes affecting their growth. The thesis examines the interaction between acid damage in the past and current growth trends and the resistance of mountain forests to current climate extremes (mainly to the effects of drought). The empirical part of the research is based on data on trends in tree-rings widths over the last two decades together with historical data of defoliation monitoring. Tree-ring width data were sampled using dendrochronological methods in the field. For this research, I selected plots along two altitudinal transects in the Krkonoše Mts. - Pec pod Sněžkou and Špindlerův Mlýn. Defoliation data were extracted from the long-term MONBASE database from the Institute of Forest Ecosystem Research (IFER). The statistical method of correlation analysis was used in order to determine the relationship between acid deposition and current tree growth. The most important correlated...
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Decoupling of environmental pressure and environmental impact from economic performance
Kovalský, Pavel ; Kovanda, Jan (advisor) ; Třebický, Viktor (referee)
7 Abstract The thesis analyses trends of two environmental aspects in spatial terms of the Czech Republic and timal terms since 1993 till 2010. The two aspects are acid deposition as environmental pressure and defoliation of forest crown as environmental impact. Since one aspect is cause of the other the thesis also analyses trends of relationship between these aspects and comapares the results with the concept of decoupling of environmental pressure from economic growth. Important findings are that despite huge relative decrease of environmental pressure expressed by acid deposition the decrease of environmental impact expressed by forest crown defoliation is very low. Although decoupling occured during the analyzed period it's not possible to say that linkage between "environmental bads" and "economic goods" was broken. The thesis reveals factors that had influence on these findings. The thesis also compares particular concepts of decoupling being used and provides author's input on which of these concepts suits the best analyzing the breakage of the links between environmental pressure from economic growth in all of its aspects. Key words: sustainable development, sustainability, decoupling of environmental pressure from economic growth, acid deposition, defoliation, gross domestic product.
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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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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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