|
|
Response of forest succession to agricultural land-abandonment in the Giant Mountains
Dobíhal, Michal ; Treml, Václav (advisor) ; Chuman, Tomáš (referee)
Response of forest succession to agricultural land-abandonment in the Giant Mountains ABSTRACT: Since the end of the 19th century, there is undergoing process of land-abandonment of mountain meadows and pastures in most of the European mountains, including the Giant Mountains. Mountain agriculture in the Giant Mountains was terminated no later than before World War II. Abandoned meadows were then subjected to secondary forest succession. The question is, how fast was this succession and how was its dynamics. My research was focused on 4 areas of interest, located in the vicinity of former mountain huts. Methods applied included the analysis of historical maps and aerial photographs and dendrochronological research of age structure of Norway spruce (Picea abies) stands. The aim of this thesis was to find out the extent of mountain agriculture near the huts and the dynamics of forest succession following land abandonment. Main peaks of seedlings establishment were observed in a very short time (10 - 20 years) following termination of mountain agriculture and in most cases these peaks were further followed by one or two more weaker peaks in the later periods. These peaks became evident in the change maps of forest development with approximately 20 years delay. Forest succession was moving gradually from the...
|
|
|
Assessment of lignin content in needles of Norway Spruce (Picea abies L. Karst.) using laboratory and image spectroscopy
Suchá, Renáta ; Kupková, Lucie (advisor) ; Brodský, Lukáš (referee)
The master thesis deals with determination of selected biochemicals (lignin, carotenoids, water) content in Norway spruce needles using laboratory and imaging spectroscopy. The first part of thesis summarizes literature dealing with methods of estimating lignin and other biochemicals content. Three types of data are used in this thesis: 1. spectra measured by contact probe and ASD FieldSpec 4 Wide Res spectroradiometer, 2. spectra measured by integrating sphere and spectroradiometer and 3. aerial hyperspectral image data acquired by APEX sensor. The most useful transformation methods - first derivative and continuum removal are applied to the spectrum. Further the linear relationship between measured spectrum and content of biochemicals is analysed. Stepwise multiple linear regression is applied to select suitable wavelengths for modeling of biochemicals content in spruce needles. The model is also calculated and applied on the level of image hyperspectral data. Maps of lignin content in Norway spruce are the final output of these part of this. Next part of the thesis compares spectra measured by contact probe and spectra measured by integrating sphere. Diffrerence between the studied areas based on biochemicals content in spruce needles and several chemical elements in the soil and based on...
|
|
|
Surface ozone as a factor of oxidative stress in mountain forests.
Bendáková, Hana ; Hůnová, Iva (advisor) ; Matoušková, Leona (referee)
This study presents mountain forest Norway spruce (Picea abies) injured by surface ozone and oxidative stress. Norway spruce is not a sensitive species but it is the most representative tree in our country and this is the reason to pay attention on its injury. Study was connected to the ozone measurement by CHMI in Jizerske mountains. Aim of our study was to find influence of surface ozone on the forest and show correlation between ozone concentrations, altitude and Norway spruce injury. Ozone concentrations are growing with the altitude. Increasing percentage of injury with growing concentrations and altitude was expected. Needles were collected at the altitude 750-1100 meters. Collected needle years were 2006, 2007 and 2009. The 2009 year was not evaluated because no symptoms were found. Injury was observed on the maroscopical, microscopical and biochemical level. Visual injury was assessed by percentage of injured needle surface by chlorosis and necrosis. Microscopical analysis studied injury on cross and longitudinal sections of needles. On the longitudinal sections were visible typically bone-cells. These cells have lost its shape by ozone stress and were narrowed in its width. Bone-cells were best visible near the stomata. Four symptoms were observed on the cross sections: tannin...
|
guest ::
