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Využití ohnutých dílců z borovice v konstrukci "hladké" jídelní židle
Juračka, Jaroslav
The aim of this diploma thesis is to consider the maximum use of bent parts in the design of a smooth dining chair with respect to the physical and mechanical properties of Pine wood. It also compares the strength properties of the three variants of the structural bonding of the reinforcing arc with the bearings and the smooth dining chair legs. Identify the strength properties of selected structural joints in the design of a smooth dining chair and statistically evaluate the results. The bending moment and the stiffness of the joint were determined for joints. They also describe the physical and mechanical properties of Pine Forest and the production of bent parts.
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Vliv částečného poškození kůry na anatomickou stavbu nově vytvořeného dřeva u juvenilních jedinců borovice lesní
Pýcha, Tomáš
The aim of this thesis was to determine whether bark damage on one side of a stem causes changes in wood anatomy. During the growth season a strip of bark was removed on half the circumference of stem of eight trees. After the end of growth season thin cross sections of stems were made from above and below the removed strip of bark. On these sections number of tracheids, their dimensions and radial wood increment were measured. Number of tracheids and radial wood increment on damaged side of the stem was 30-50 % lower below than above the wound. Radial width of tracheids on the damaged side of the stem was 14-16 % lower than on the undamaged side. Tracheid cell wall thickness was also lower on the damaged side of the stem where it was 7-20 % thinner compared to the undamaged side.
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Development and interpretation of site tree-ring chronology of Pinus sylvestris
Mašek, Jiří ; Treml, Václav (advisor) ; Šefrna, Luděk (referee)
The presented bachelor thesis deals with the study of climatic factors that influence the growth of the pine (Pinus sylvestris) in the locality near Rabštejn nad Střelou. The primary objective was to determine the limiting factors of tree growth and to perform dendroclimatic reconstruction. For this purpose, samples were taken at the site and local chronologies were created using various standardization methods. Using the correlation coefficients, limiting growth factors were determined, and reconstruction by regression and scaling was performed based on the highest correlation. The results showed a strong relationship of rings width to rainfall and humidity conditions, especially in the summer months and in various seasons from April to August. Most of the chronologies also showed the positive influence of February temperatures. Observed signature rings in many cases are well responsive to various climatic anomalies. For the most correlated variable, dendroclimatic reconstruction was calculated for the period 1850 - 2016 when the chronology was reliable. The reconstructed average rainfall corresponds well with the Klementinum climate line and other rainfall reconstructions.
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Postavení modřínu opadavého a borovice lesní ve smíšených lesních porostech na ŠLP Křtiny
Dobrá, Alena
The bachelor thesis was aimed at assessing the state Larix decidua Mill and Pinus sylvestris L. in mixed forests at ŠLP Křtiny before the commencement of the application of the principles of natural management. In first part was conducted analysis position of species based of forest management plan data. In second past was established and evaluated two plots of mixed pine and beech. In third part was designed alternative cultivation areas for research. It was found that 77 % area of ŠLP Křtiny forms mixed forests. In forests is most abundant beech (31 %). The pine was represented 9,3 %, larch 9,8 %. The average hight of pine was 25 meters and average breast-height diameter was 35 centimeters in mixed forests. The average hight of larch was 30 meters and average breast-height diameter was 40 centimeters in mixed forests. Stand basal both of species was bigger than the tabulated. Also it found that pine was badly damaged by crown break. The highest production of larch was at research area number two at area mixture (0,63 m3) but total production capacity of species was higher at research area number one. The comparison of beech, pine and mixtures between themselves was founded that pine was bigger everywhere. They were proposed two ways of silvicultural measures. The first method has been designed for near-natural farming and second method has been designed for feeling by regulated areas.
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Ohýbání borového dřeva
Juračka, Jaroslav
This thesis deals with the bending of Pine. What is important is the actual selection of material to be free of defects and with maximum equality of fibers. We soaked wood and then rapped it. We the steamed wood bent manually using a flange and the block into three kinds of radii. By this experiment we found the possibilities of bending pine and we measured the defects during bending
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Remnant of forest at the transition from Late Glacial period to Holocene: dendroecological and palaeobotanical reconstruction
Moravcová, Alice ; Šamonil, Pavel (advisor) ; Rybníček, Michal (referee)
The remains from a sub-fossil pine forest burried in layers of peat deposits at the northern edge of the CHKO Křivoklátsko in the Central Bohemia is completely unique findings for the area of the Czech Republic. It offers new opportunities for palaeoenvironmental reconstruction and related climate changes during the Late Glacial and early Holocene epoch. The methods of dendrochronology and radiocarbon dating were used to date subfossil trees. The results of radiocarbon dating determined the existence of the forest in the period approximately 12,000 to 10,300 cal yr BP. The dendrochronological analyses revealed two continuous floating chronologies. The chronology RD4, which is long 200 years, originates from the Younger Dryas. The chronology RD6, 300 years long, originates from the Preboreal. The growth dynamics of the forest were reconstructed on the basis of the tree- ring analysis. Hydrological regime has been identified as a major disturbancy factor that influenced the growth of trees. This has been evident from synchronous phase depressions in the growth of synchronized tree-ring series. The high water table was the main cause of their extinction. This was in concordance with the results of macrofossils analyses. The effect of hydrological regime was largely influenced by microsite differences...
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Sensitivity of Scotch pine ring-width chronologies to climatic variables
Lehečková, Eliška ; Treml, Václav (advisor) ; Vejpustková, Monika (referee)
Presented master's thesis deals with the climate sensitivity of radial growth of Scots Pine (Pinus sylvestris) growing in the Protected Landscape Area Kokořínsko. The principal aim was to find out whether there are differences in the climate-growth response of pines growing on dry and mesic sites. To cope with that question tree ring cores were collected from stands on dry sandstones plateau and from stands near valley bottom with better water supply. Residual chronologies were developed and climatic factors limiting growth were identified using partial correlation analysis. The results show that pines on rocky sites respond positively to high precipitation during the vegetation season whereas trees on wetter sites react positively to high temperatures. In most study stands high February temperatures positively affect radial growth. Moving partial correlations analysis showed that the strongest responses to month climatic variables were stable over the studied period 1902 - 2009. Pointer years were determined and compared with precipitation and temperature anomalies in the corresponding pointer year, furthermore the effect of climate on number of trees with growth anomaly was studied using partial correlations analysis. Results of these analyses were in compliance with the previous findings. In...
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Impact of Silvicultural Measures on Some Mechanical Wood Properties of Scots Pine
Schönfelder, Ondřej ; Zeidler, Aleš (advisor) ; Bílek, Lukáš (referee)
The purpose of this study is to assess the impact of silvicultural measures on selected mechanical properties of Scots pine of the area Doksy and Plasy. Each area is characterized by growths that are typical for the locality. From areas Doksy were selected 3 stands and 2 from Plasy region. For each crop were chosen representative of the trees that were cut down, and testing material was produced. On test samples was determined density at 12 % level moisture, modulus of rupture, modulus of elasticity, toughness and compression strength in the fiber direction. All tests were carried out by standardized procedures. Using statistical methods, it was found that a statistically significant value of compared areas were only in the density. The others properties which were examined in the areas are statistically insignificant. However, when assessing individual stands with ANOVA was generally for the most of properties found statistically significant difference. This suggests that the pine wood properties are dependent on location. In horizontal plane strain was found a statistical significance for all of the tested characteristics. That shows that the position of the wood in the stem has impact on the mechanical properties. Furthermore, the individual results were evaluated in terms of dependence on the density. Which resulted in the majority of cases middle to high dependency.
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Comparison of bark boring species composition on douglas-fir and pine
Košík, Kamil ; Pešková, Vítězslava (advisor) ; Šenfeld, Petr (referee)
This work deals a comparison the diversity of species of bark beetles on Douglas fir (Pseudotsuga menziesii Mirb./Franco) and Scots pine (Pinus sylvestris L.). On location the Green Shed in the Central Region of the Czechia were laid 24 traps, so that Douglas fir and Scots pine formed a couple. They were prepared two variants - trees up to 30 years and a trees of 40 - 60 years old. Evaluation took place after four sections in the relative distances. Research has shown that the both species of the trees were not broad spectrum of bark beetles. On Douglas fir it was only a Pityogenes chalcographus L., who was found in only one trap tree at the age of 30 years, and on the Scots pine trap tree was found only Tomicus piniperda L., but it was found in most traps.
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Environmental factors effect to the Scotch pine seedlings survival
Pourová, Marie ; Ulbrichová, Iva (advisor) ; Janeček, Vladimír (referee)
The survival and mortality of the Scots Pine (Pinus sylvestris) seedlings during the vegetation season of 2015 are evaluated in the thesis. The seedlings in greenhouse conditions in Truby were exposed to water deficiency, three variants of shading and simultaneously to environmental temperature, which, due to weather, was extraordinary high at the time of the experiment.
The highest number of grown seedlings from the seed material from Plasy was 89 % from the total of 224 outplanted ones, namely in conditions of mean shading and slightly reduced watering. The highest mortality of the seedlings was found in unshaded environment with slightly reduced watering, in mean shading with the second lowest watering and in the highest shading with the second lowest watering, the mortality was 100 % there. The seedlings from the seed material from Doksy were much more hard put to it. The seedlings grew only in four cases in unshaded environment with the highest watering (4 % from 224 outplanted ones), in mean shading with the highest watering (38 %) and in the environment with the highest shading together with the highest watering (68 %) and slightly lowered watering (1,3 %). In all cases the seedlings mortality was higher than 70 %.
The lowest number of grown seedlings occurred in unshaded environment and between the variants with mean and high shading, there was only a small difference. The results were strongly affected by extraordinary warm vegetation season.
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