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The bark beetle and decline of the spruce forests - educational program
KOŠKOVÁ, Anna
Bachelor thesis focuses on creation of educational curriculum about bark beetle and decline of the spruce forests. Whole curriculum is aimed to pupils of the 6th and 7th class of elementary schools. The literature review deals with forest vegetation stages, life cycle of the bark beetle, then there are described ways how to avoid its uncontrollable spreading and possibilities of growing new and resistant forests. Practical part of this bachelor thesis is devoted to educational curriculum itself. In conclusion is discussed the usage of this curriculum in other educational facilities.
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Model přežívání smrku ztepilého v podmínkách gradace lýkožrouta smrkového
ONDŘICHOVÁ, Nikola
As a result of the gradation of the bark beetle, there is often extensive damage to spruce stands. Although not only damaged but also healthy stands are attacked during massive gradation, there are individuals who survive this gradation. The aim of this thesis was to determine which selected environmental variables affect the survival of trees in the conditions of gradation of the bark beetle. The area of interest of my thesis was the Březník area, located in Šumava. The evaluation showed that a strong effect increasing the probability of stands survival was manifested in the variable containing edaphic categories, especially in the edaphic category of the 9th class. This class represents a waterlogged permanently wet area, which increases the probability of vegetation survival and largely corresponds to humidity conditions. The distance to the natural edges of the stand also contributes to the increasing probability of survival. This thesis can be useful with its results and conclusions in the field of forest management.
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Detection of bark beetle attack of Norway spruce using spectral and biophysical data at different hierarchical levels
Vesecká, Martina ; Albrechtová, Jana (advisor) ; Tomášková, Ivana (referee)
There was created an overview of key aspects for a correct understanding of the dynamics between bark beetle and Norway spruce, especially the way of life of the beetle and the time course of its life cycles. It is absolutely essential to understand this interaction for a timely and effective solution to the bark beetle calamity. Furthermore, the mutual interaction of beetle and tree is discussed in detail in the text. Great emphasis is placed on the description of the spruce's defense mechanisms and the consequences of the attack. In particular, biophysical changes in the needles, which cause a change in the spectral behaviour of the leaves and thus the entire forest stand. Using sensor capable of measuring the reflectance of surfaces, it is possible to detect a bark beetle-infested tree much earlier than changes in the needles could be detected by the naked eye and remove it while it is still colonized by the beetle and not spreading further into surrounding trees. This is key to managing not only the current bark beetle calamity. An overview of case studies is given in the thesis, where the use of spectral methods at different hierarchical levels was applied and satisfactory accuracy in the identification of early infested trees was achieved. Key words: Norway spruce, bark beetle, bark beetle...
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Influence of mountain farming termination on forest stands in the east part of the Krkonoše Mts.
Mach, Dominik ; Treml, Václav (advisor) ; Romportl, Dušan (referee)
This thesis focuses on the evaluation of the impact of abandonment of agricultural land on forest stands in the eastern part of the Krkonoše Mountains. The aim of this thesis is to reconstruct the evolution of the forest response to gradual termination of mountain farming. Specifically, I analysed the age structure of Norway spruce (Picea abies) and described the dynamics of secondary forest succession in meadow enclaves around huts. Three main research methods helped meeting the above-mentioned objectives of the thesis. The first is the analysis of old maps. The second is segmentation and supervised classification of aerial photographs. The last is dendrochronological research of the age structures of Norway spruce. Research showed the expansion of forest stands into treeless grassland enclaves. The main driving force behind this process of secondary succession has been the gradual decline of mountain farming. After the end of mountain farming in the middle of the 20th century,the dynamics of forest succession in meadow enclaves increased significantly, with the highest rate of succession in the following 20 years. Forest succession took place mainly along the edges of meadow enclaves. Inside the meadow enclaves, trees were mostly established along streams. The most significant factor that...
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Laboratory/Field Spectroscopy and Remote Sensing Image Data for Vegetation Studies
Červená, Lucie ; Kupková, Lucie (advisor) ; Pavelka, Karel (referee) ; Müllerová, Jana (referee)
Dominant vegetation species of two structurally and functionally different montane ecosystems were studied by means of laboratory and field spectroscopy and remote sensing image data: (1) a homogeneous human-influenced evergreen coniferous forest represented by a Norway spruce forest in the Krušné hory Mountains and (2) a heterogeneous natural ecosystem of a relict arctic-alpine tundra in the Krkonoše Mountains with predominance of grasses. The first part dealing with the Norway spruce forest is especially focused on the methods of laboratory spectroscopy. The assessment of Norway spruce stands on a regional and a global scales requires detailed knowledge of their spectral properties at the level of needles and shoots in the beginning, but ground research is very time-demanding. Open spectral libraries could help to get more ground-truth data for subsequent analysis of tree species in forests ecosystems. However, the problem may arise with the comparability of spectra taken by different devices. The present thesis focuses on a comparability of spectra measured by a field spectroradiometer coupled with plant contact probe and/or two integrating spheres (Paper 3) and proves the significant differences in spruce needle spectra measured by the contact probe and integrating sphere, spectra of...
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Application of imaging spectroscopy in monitoring of vegetation stress caused by soil pollutants in the Sokolov lignite basin
Mišurec, Jan ; Kupková, Lucie (advisor) ; Pavelka, Karel (referee) ; Homolová, Lucie (referee)
Forests can be considered as one of the most important Earth's ecosystems not only because of oxygen production and carbon sequestration via photosynthesis, but also as a source of many natural resources (such as wood) and as a habitat of many specific plants and animals. Monitoring of forest health status is thus crucial activity for keeping all production and ecosystem functions of forests. The main aim of the thesis is development of an alternative approach for forest health status based on airborne hyperspectral data (HyMap) analysis supported by field sampling. The proposed approach tries to use similar vegetation parameters which are used in case of the current methods of forest health status assessment based on field inspections. It is believed that importance of such new methods will significantly increase in the time when the planned satellite hyperspectral missions (e.g. EnMap) will move into operational phase. The developed forest health monitoring approach is practically demonstrated on mature Norway spruce (Picea abies L. Karst) forests of the Sokolov lignite basin which were affected by long-term coal mining and heavy industry and therefore high variability of forest health status was assumed in this case. Two leaf level radiative transfer models were used for simulating spectral...
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Tree-ring chronologies of Norway-spruce on west-east longitudinal gradient in the mountain ranges of central Europe
Ponocná, Tereza ; Treml, Václav (advisor) ; Kolář, Tomáš (referee) ; Vejpustková, Monika (referee)
The Earth's climate system has recently experienced substantial warming which likely impacts temperature-limited communities close to their distribution margins. The alpine treeline ecotone represents upper distributional limit of montane/subalpine forests. This biogeographic boundary relies mainly on decreasing temperature with increasing elevation. Surprisingly the response of treeline ecotone to ongoing warming has varied a lot and the reasons of this variability are poorly understood. The aim of this dissertation thesis is the assessment of growth trends and tree ring response of Norway spruce (Picea abies[L.] Karst.) to climatic oscillations at treelines and montane forests of East-Central Europe. This dissertation deals with both inter-regional and intra-regional (aspect, elevation) variability of tree growth. The presented results are based on an extensive data set of growth curves for almost 1400 trees. All study sites revealed close relationship between tree ring widths and growing season temperatures as well as the temperatures of October preceding to ring formation season. The main site-dependent differences in growth trends and temperature responses were attributed to elevation, the effect of aspect was relatively less significant. At treelines between the Krkonoše Mts. and Nízké Tatry...
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Structure and function of chloroplasts in selected woody plants grown under increased CO2 concentration
Hlízová, Eliška ; Albrechtová, Jana (advisor) ; Kutík, Jaromír (referee)
The effect of elevated CO2 concentration (EC CO2) on photosynthesis has been observed on many hierarchical levels. There was a significant increase in the rate of photosynthesis of examined trees observed in previous studies thus I hypothesised these changes are accompanied by changes of chloroplast ultrastructure and photosystem content and function and the main aim of this study is to evaluate these adjustments. In this study 13 - 14 years old seedlings of Norway spruce (Picea abies L. Karst.) grown in glass domes with adjustable windows - one with ambient CO2 concentration as a control, the other one with simulated EC CO2 (700 ppm) - during the vegetative season were examined. Pigment content, fluorescence and reflectance indexes, activity of photosystem 1 (PS1) and 2 (PS 2) of isolated chloroplasts, size of cross-sectional area of chloroplast and proportion of stromal to granal thylakoids under EC CO2 treatment were investigated. Although there was a significant increase in the maximum rate of photosynthetic assimilation of trees from EC CO2 (observed by other researchers of our team), decreased chlorophyll and carotenoid content as well as the activity of both photosystems were observed, which is usually atributed to photosynthetic acclimation. As the rate of decrease of photosystem 1 and photosystem 2...
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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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Deep learning for tree line ecotone mapping from remote sensing data
Dvořák, Jakub ; Potůčková, Markéta (advisor) ; Lefèvre, Sébastien (referee)
Deep learning is growing in popularity in the remote sensing community, especially as a classification algorithm. First part of this thesis describes deep neural networks commonly used for remote sensing classification and their various applications. Capabilities of selected geospatial software suites in relation to deep models are also discussed in this part. Theoretical findings from the first part of the thesis are validated using two deep convolutional Encoder-Decoder networks - U-Net and its proposed adaptation called KrakonosNet. They are used to perform a sematic segmentation of spruce trees and dwarf pine shrubs in the tree line ecotone of the Krkonoše Mountains, Czechia. A normalised digital surface model is employed for creation of sufficiently large amount of training data, while the classification itself is performed using only optical imagery with very high spatial resolution. Resulting classification is compared to a set of traditional remote sensing classifiers, namely Maximum Likelihood, Random Forest, and a Support Vector Machine. Both U-Net and KrakonosNet significantly outperform the other classifiers on this dataset and will be consequently used in a related research project. Key words deep learning, U-Net, Krkonoše mountains, classification, vegetation mapping, picea abies,...
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