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Drought stress response of European beech seedlings monitored using physiological and optical indicators.
Červenka, Ondřej ; Lhotáková, Zuzana (advisor) ; Gebauer, Roman (referee)
One of the manifestations of global climate change is an increase in extreme temperatures and drought waves, while forecasts of future development indicate deepening negative impacts. The effect of these abiotic stress factors is reflected in the physiological state of the vegetation. It is therefore necessary to find suitable stress indicators that will help detect the worsening of physiological state of vegetation in time series. Indicators can be detected not only by physiological methods, but also optical ones, for further use of vegetation monitoring by remote sensing methods. Forest beech (Fagus sylvatica L.) is a native tree in our context, currently widely used in forestry for planting more species-varied communities of trees that are more resistant to the effects of climate change. The aim of the thesis was to study the responses of beech to drought stress using physiological and optical indicators. Beech seedlings (planting material from the nursery) were placed in containers in the experimental greenhouse for two experimental seasons, water supply was mediated by drip irrigation. The experimental material was divided into three groups with graded irrigation (control, moderate drought and drought). The watering regime consisted of three periods of drought and recovery phases with uniform,...
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Physiological status of young silver fir on stands with different microclimate using biochemical, and optical needle traits.
Kabilková, Eva ; Lhotáková, Zuzana (advisor) ; Pokorný, Radek (referee)
Silver fir (Abies alba Mill.) is a candidate tree species in the process of forest transformation especially of spruce monoculture stands (Picea Abies (L.) H. Karst.), thanks to its better growth characteristics in conditions of mild drought. However, fir, as a very shade tolerant tree, may be more susceptible to various abiotic stressors in more open forest canopies, and therefore it is necessary to study its ecological requirements in connection with the most effective possible application in forestry. In this thesis, the physiological state of young fir stands affected by different light microclimatic conditions, which were represented by different types of forest regeneration, was studied. Specifically, it is shelter-wood cut, which represents the likely highest degree of shading by mature trees, then natural regeneration under sparse canopy, gap cut and small clear cut, which represent a moderate degree of shading by mature trees, and last but not least, clear cut, which represents the lowest degree of shading. Physiological status was evaluated using biochemical and optical properties of the needles, and additional microclimatic conditions of the habitats, namely temperature and soil moisture, were also evaluated. Our results showed that the used biochemical and optical properties of the...
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REMOTE SENSING-BASED ANALYSIS OF MULTISPECTRAL INDICES
Janoušek, Jiří ; Kačmařík,, Michal (referee) ; Nedělník,, Jan (referee) ; Marcoň, Petr (advisor)
The thesis discusses various perspectives on the analysis of multispectral images, emphasizing in particular the technique’s potential in remote sensing of the Earth. Within multispectral imaging, the author has explored diverse methods for scanning plants to examine the impact exerted by the invididual electromagnetic spectrum components on the reflectivity of the investigated vegetation. Regarding the relevant vegetation indices, one of the main activities lay in comparing the approaches employed to compute the indices from applicable multispectral images. To deliver general data on the state of the plants being grown, the research involved designing and structuring relevant indicators that enabled the author to correlate the multispectral indices. In this context, the final sections of the thesis present the spectral maps acquired from the multispectral camera images and expose the analyses centered on the resulting index values, the aim being to help determine reliably the optimum harvest time in agricultural crops. The output of the project outlined within the thesis is then embodied in novel linear regression models that facilitate defining the optimum such a time. Importantly, by extension, the author also proposes a compact methodology that covers the individual phases and steps between the vegetation imaging the crops and finding the optimum harvest time.
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Multispectral Analyse of Image Data
Novotný, Jan ; Druckmüller, Miloslav (referee) ; Martišek, Dalibor (advisor)
The airborne hyperspectral remote sensing is used as an approach to monitor actual state of environmental components. This thesis covers priority treatment to analyse of hyperspectral data with the aim of a tree crowns delineation. Specific algorithm applying adaptive equalization and the Voronoi diagrams is designed to subdivide a forest area into individual trees. A computer program executes the algorithm and allows testing it on real data, checking and analyzing the results.
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Evaluation of the physiological status of European beech in its plantings on localities following the gradient of its ecological valence
Palouš, Daniel ; Albrechtová, Jana (advisor) ; Tomášková, Ivana (referee)
European beech (Fagus sylvatica L.) is one of the dominant tree species in Europe, presenting a keystone species for forest ecosystem functioning. The ongoing climate change alters the environmental conditions in the areas of the current distribution of European beech, leading to stress. Concerning the critical health status of forests in the Czech Republic and other European countries, it's even more urgent to monitor the health status of forests. For this, tools for early detection of a stand's physiological status decline are needed. The aforementioned tools can consist of indicators of the physiological status suggested by this thesis. This thesis aims to evaluate the applicability and sensitivity of the preselected set of indicators of the physiological status of European beech to the gradient of environmental conditions (temperature, precipitation) within its ecological valence. Four stands of European beech presenting the gradient of beech's ecological valence were observed over the peak of one vegetation season. Stand Kocanda presented the microclimatic and ecological optimum; stand Hradecko was on the lower margin of the altitudinal gradient of European beech distribution and presented the limit of low water availability; stand Deštné was on the upper margin of the altitudinal gradient of...
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Possibilities of using satellite data Sentinel-2 in landscape planning
TOMS, Petr
The diploma thesis focuses on the analysis of land cover changes and characteristics of humidity in the Dobřejovický stream basin, using Sentinel-2 data. The aim of the work was to find out how the obtained results can be used for landscape planning. The first part of the thesis deals with the literature search, which is based on the principles of remote sensing, electromagnetic spectrum, spectral expression of objects, multispectral data and and satellite data Sentinel-2, provided by the European Space Agency. The practical part contains the description of the area of interest, the methods used in processing Sentinel-2 data. An important part is focused on the classification of data from which the outputs are created, the results are interpreted and the evaluated accuracy of the classification of land cover changes. Furthermore, the practical part is devoted to the calculation of vegetation indices, thanks to which we can obtain information about humidity characteristics. Part of the work also points to the usability of the obtained results in the forms of landscape planning.
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Analysis of long-term changes of vegetation indices
Beránková, Petra ; Štych, Přemysl (advisor) ; Jedlička, Jan (referee)
The work deals with the issue of research of long-term changes of vegetation indices concretely indices NDVI (Normalized Difference Vegetation Index). The first part is devoted to detailed analysis of domestic and foreign literature, which deals with the calculation and interpretation of vegetation indices values. The main theme of this work is to explore relation between temperature and NDVI changes and precipitation and NDVI changes over the period 1982-2006. These connections are examined using correlation and regression analysis. Attention is concentrated to the Czech Republic, Central Europe and Finland. The average value of NDVI in Central Europe increased over the study period of 0,0012 per year. The average value of NDVI in Czech Republic increased of 0,0014 per year. On the territory of the Czech Republic increased the value of NDVI in three seasons (spring, autumn and winter). In the summer, in some areas, decreased NDVI values. Correlation coefficients between NDVI and temperature and NDVI and precipitation appeared consistently the highest in the spring. Keywords: NDVI, vegetation indices, temperature, precipitation, Central Europe, Czech Republic
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Development of selected invasive species and meadow vegetation classification algorithm in the Krkonoše Mountains using hyperspectral data
Jelének, Jan ; Kupková, Lucie (advisor) ; Halabuk, Andrej (referee)
Development of selected invasive species and meadow vegetation classification algorithm in the Krkonoše Mountains using hyperspectral data Abstract The thesis deals with utilization of airbone APEX hyperspectral image data for selected invasive species and meadow vegetation classification in the study area of the Krkonoše Mountains National Park. The mian goal of the thesis was to develop of classification algorithm based on proposed vegetation indices. The approach was based on the utilization of in-situ LAI, fAPAR, chlorophyll content data and analysis of their relation with vegetation spectral properties. The work also deals with several problems regarding LAI - vegetation indices relationship, namely saturation of LAI and mutual correlation of LAI and chlorophyll content. Tha classification was focued on invasive species Rumex alpinus and Lupinus polyphyllus, meadow vegetation with dominant Nardus stricta and dominant Trisetum flavescens and cutted lawns. Besides the proposed approach, the presented work resulted in several classification maps of study area and in spectral libraries, containing ground level spectra of studied invasive species, meadow vegetation types and several other meadow species. Keywords: hyperspectral image data, APEX, LAI, fAPAR, vegetation indices, invasive species, meadow...
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