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Dendrochronological dating of catastrophic slope movements
Tumajer, Jan ; Treml, Václav (advisor) ; Burda, Jan (referee)
Mass-movements are one example of natural processes that can pose a serious risk for human beings and their possessions. Dendrochronology, a method capable of their reconstruction, can provide parameters of former events, which can be used for planning protective measures. The possibilities for the application of dendrochronological methods have been tested by means of meta-analysis of electronic and printed scientific articles and a case study focused on former avalanche activity in Schustler's avalanche path (Labský důl, Krkonoše Mts.). The main conclusion of the first one is the clear spatial disproportion of the recent dendrogeomorphological research activities - e.g. the dating of avalanches is typical for mountains of Montana (USA); the Alpine region (mainly Switzerland), on the other hand, absolutely dominates in the research of debris-flows. In the case study, the analysis of material with well-chosen indicators led to high accuracy results comparable with the results of scientific articles focused on avalanches, and made the identification of 14 years (in the period 1953-2007) with potential avalanche acitvity possible. Although methods of dendrogeomorphology are usually neglected in the research of avalanches in the Czech republic, their great potential for future applications is shown....
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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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Quantitative vessel parameters of broadleaves as a tool for reconstruction of physical geographical processes
Tumajer, Jan
Trees adjust wood anatomical structure to environmental conditions, predisposing time series of quantitative wood anatomical parameters to be valuable source of palaeoenvironmental information. In this doctoral project we analysed the response of vessel parameters of i) floodplain Quercus robur to groundwater level fluctuation, hydroclimate variability and extreme events (droughts and floods), and of ii) Betula pendula to mechanical damage caused by various disturbances. Although climatic signal as well as pointer years stored in tree-ring width chronologies of Quercus robur largely differ between sites, quantitative vessel parameters contain spatially- homogenous positive signal of previous year summer temperature and current year winter/early spring temperature. The only between-site difference in wood anatomical chronologies is negative effect of moisture on vessel size in floodplain, which does not occur in not-flooded lowland sites. We suggest that while tree productivity benefits from high water availability, the wood anatomical structure of Quercus robur is constrained by high soil water saturation in floodplain zone. In addition, the response of tree-ring widths to moisture availability is not uniform inside single stand, but subgroups of trees with completely opposite response coexist...
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System of natural fire risk indicators (verification of various risk assessment procedures occurrence of natural fires) including instructions for the use of the integrated forecast system
Trnka, Miroslav ; Čermák, Petr ; Kudláčková, Lucie ; Balek, Jan ; Semerádová, Daniela ; Brovkina, Olga ; Zemek, František ; Štěpánek, Petr ; Zahradníček, Pavel ; Skalák, Petr ; Bláhová, Monika ; Jurečka, František ; Janouš, Dalibor ; Žalud, Zdeněk ; Marek, Michal V. ; Cienciala, Emil ; Beranová, J. ; Zatloukal, V. ; Albert, J. ; Tumajer, J. ; Možný, M. ; Hájková, L. ; Chuchma, F.
The presented methodology represents an improvement of the currently used system of wildfire monitoring and forecast. Based on extensive testing, it defines two fire weather indices. The method shows how the combination of both indices can lead to robust fire risk estimates. Both indices were uset to generate a forecast of fire weather, but also to quantify th erelationship between the frequency of favorable conditions for the occurrence of natural fires and their observed numbers, in several time steps (from 1 day to the entire season) The methodology has been implemented within the www. firerisk.cz portal, where it serves as a tool for operational fire risk forecasting. The text of the methodology therefore contains instructions for using the menthodology therefore contains instructions for using the firerick.cz portal. Great attention is paid in the methodology to the aspect of climate change and estimating the impact of this phenomenon on the frequency of wildfires in the Czech republic.
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Recommended adaptation and mitigation measures in risk areas of natural occurrence fires in the light of the changing climate
Trnka, Miroslav ; Čermák, Petr ; Kudláčková, Lucie ; Balek, Jan ; Semerádová, Daniela ; Brovkina, Olga ; Zemek, František ; Štěpánek, Petr ; Zahradníček, Pavel ; Bláhová, Monika ; Cienciala, Emil ; Beranová, J. ; Zatloukal, V. ; Albert, J. ; Tumajer, J. ; Možný, M. ; Hájková, L. ; Chuchma, F.
The methodology formulates graded adaptation and mitigation measures to mitigate fire risk and spread fire in the countryside (forest and agricultural land). To this end, a variant assessment procedure is presented fire risk according to the user's data capabilities. The algorithmization of fire risk in forests is based on forest typology to assess habitats, and adds forest vegetation characteristics. On agricultural Soil agronomic factors include crop type, cover cover, habitat and water characteristics regime. For both territorial categories, the expected impacts of climate change on fire risk are given habitat in the medium term (by 2050). Methodology in conclusion on a case study demonstrates the possibilities of using the model tool FlamMap for the analysis of fire characteristics.
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Quantitative vessel parameters of broadleaves as a tool for reconstruction of physical geographical processes
Tumajer, Jan
Trees adjust wood anatomical structure to environmental conditions, predisposing time series of quantitative wood anatomical parameters to be valuable source of palaeoenvironmental information. In this doctoral project we analysed the response of vessel parameters of i) floodplain Quercus robur to groundwater level fluctuation, hydroclimate variability and extreme events (droughts and floods), and of ii) Betula pendula to mechanical damage caused by various disturbances. Although climatic signal as well as pointer years stored in tree-ring width chronologies of Quercus robur largely differ between sites, quantitative vessel parameters contain spatially- homogenous positive signal of previous year summer temperature and current year winter/early spring temperature. The only between-site difference in wood anatomical chronologies is negative effect of moisture on vessel size in floodplain, which does not occur in not-flooded lowland sites. We suggest that while tree productivity benefits from high water availability, the wood anatomical structure of Quercus robur is constrained by high soil water saturation in floodplain zone. In addition, the response of tree-ring widths to moisture availability is not uniform inside single stand, but subgroups of trees with completely opposite response coexist...
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Quantitative vessel parameters of broadleaves as a tool for reconstruction of physical geographical processes
Tumajer, Jan ; Treml, Václav (advisor) ; Kolář, Tomáš (referee) ; van der Maaten, Ernst (referee)
Trees adjust wood anatomical structure to environmental conditions, predisposing time series of quantitative wood anatomical parameters to be valuable source of palaeoenvironmental information. In this doctoral project we analysed the response of vessel parameters of i) floodplain Quercus robur to groundwater level fluctuation, hydroclimate variability and extreme events (droughts and floods), and of ii) Betula pendula to mechanical damage caused by various disturbances. Although climatic signal as well as pointer years stored in tree-ring width chronologies of Quercus robur largely differ between sites, quantitative vessel parameters contain spatially- homogenous positive signal of previous year summer temperature and current year winter/early spring temperature. The only between-site difference in wood anatomical chronologies is negative effect of moisture on vessel size in floodplain, which does not occur in not-flooded lowland sites. We suggest that while tree productivity benefits from high water availability, the wood anatomical structure of Quercus robur is constrained by high soil water saturation in floodplain zone. In addition, the response of tree-ring widths to moisture availability is not uniform inside single stand, but subgroups of trees with completely opposite response coexist...
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Dendrochronological dating of the past avalanche events in the Krkonose Mts.
Tumajer, Jan ; Treml, Václav (advisor) ; Kociánová, Milena (referee)
Avalanches are important natural processes which shape the character of large mountainous areas. The reconstruction of their history has been performed on avalanche tracks in the Důl Bílého Labe Valley, Krkonoše Mts. through application of dendrogeomorphological methods. In total 101 trees from the area of 5 avalanche tracks were cored or cross-sectioned, which helped to identify 1253 growth disturbances (abrupt growth suppressions or releases, increases in tree-ring eccentricity, traumatic resin ducts, reaction wood, callus or determination of the tree death). The analysis spanning period from the 1859 led to the identification of 40 avalanche events, which prolong and complement written evidences of avalanche falls (avalanche cadastre). However, because of limitations of dendrogeomorphology (especially impossibility of dating of small events), these results have character of only minimal number of events. Strong influence of monthly snow melting and snow accumulation on initiation of events was pointed out through the statistical analysis of snowpack changes in relation to the reconstructed avalanche activity. Two main possible natural reasons for avalanche activity initiation were identified - vast spring snow melting and loading with fresh snow. The analysis demonstrates the potential of...
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Dendrochronological dating of catastrophic slope movements
Tumajer, Jan ; Treml, Václav (advisor) ; Burda, Jan (referee)
Mass-movements are one example of natural processes that can pose a serious risk for human beings and their possessions. Dendrochronology, a method capable of their reconstruction, can provide parameters of former events, which can be used for planning protective measures. The possibilities for the application of dendrochronological methods have been tested by means of meta-analysis of electronic and printed scientific articles and a case study focused on former avalanche activity in Schustler's avalanche path (Labský důl, Krkonoše Mts.). The main conclusion of the first one is the clear spatial disproportion of the recent dendrogeomorphological research activities - e.g. the dating of avalanches is typical for mountains of Montana (USA); the Alpine region (mainly Switzerland), on the other hand, absolutely dominates in the research of debris-flows. In the case study, the analysis of material with well-chosen indicators led to high accuracy results comparable with the results of scientific articles focused on avalanches, and made the identification of 14 years (in the period 1953-2007) with potential avalanche acitvity possible. Although methods of dendrogeomorphology are usually neglected in the research of avalanches in the Czech republic, their great potential for future applications is shown....
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