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Vyhodnocení plantáže RRD založené na zemědělské půdě v majetku Lesů města Brna, a.s.
Stuchlý, Ondřej
The work deals with the analysis of production and economic parameters of plantation short rotation coppice LMB in LS Deblín. Production plantation was assessed after 7 and 8 years since its inception through a network of inventory plots and stencil poplar. Surveys to be wood volume (m3) and the total biomass (o.d.t). Plantation economy was measured as the difference between revenues and costs. The survey was also regenerative experiment to assess the influence of the width of the cuts on the growth of poplar saplings. Total volume production of tree plantations for 2012 was set at 46,95 +/-9,7 m3. Total volume production of tree plantations for 2013 was set at 63,41 m3 +/-10,5 m3. Total dry weight biomass for 2012 amounted to 23,31 t/ha ie 3,33 t/ha/year. The following year, the total biomass dry weight was for 8,42 t/ha greater. The average production was also greater, it reached 3,97 o.d.t/ha/year. The total cost of the plantation in the first rotation reached 79 022 CZK. The cost of timber harvesting in 2012 amounted to 7 485 CZK. The total yield of the plantation in 2012 was 72 906 CZK. The profit in 2012 amounted to -6 116 CZK . Total revenue for 2013 amounted to 99 249 CZK. The profit in 2013 amounted to 20 227 CZK. Next experiment shows vigorous sprouting capacity. Wider cuts (3 lines) is generally larger than the cuts closer (2 lines). It was also found that the wider lines is greater proportion of sprouts in the greatest height class (+2 m).
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Ekonomická, ekologická a environmentální analýza pro odlišnou dřevinnou skladbu na LZ Židlochovice
Otáhal, Josef
The main content of the thesis comparing selected stands at LZ Židlochovice. Forests were compared with a predominance of English oak (Quercus robur), black walnut (Juglans nigra) and poplar stands (Populus spp.). It was not pursued only production functions, but the thesis deals with evaluation of non-production functions of forests and their social importance for the population. The results indicate that the selected forests at LZ Židlochovice have high bioproduction and sanitary-hygienic function. Conversely ecological functions - stabilization is low. In economic terms can return from the forests very high, assuming grow quality range
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Návrh inovace konstrukční skladby dřevěného jádra snowboardu
Bátěk, Silvestr
This diploma thesis describes the comparison of two different kinds of structures of snowboard wooden core. One is a combination of ash and poplar (long known and reliable structure currently used by the company Hackboards Ltd.). The other is tested combination when abele is replaced by lighter balsa wood. For both types of core the same types of fibreglass, base and top sheet are used (triaxial fibreglass, sintered base, protective top sheet). The individual mouldings were cut to the required sample on which the tests were made for the determination of bending strength according to ČSN EN 310 and impact bending according to ČSN EN ISO 179-1. Then according to ČSN EN 322 and ČSN EN 323 the moisture and density of used wooden boards were set. The measured results were evaluated and presented in charts and tables in the experimental part of this work.
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Produkce výmladkové platáže topolu japonského (J-105) v druhém obmýtí na majetku Lesy města Brna a.s.
Komarov, Tomáš
This thesis deals with the study of a biomass production of a coppice plantation of a fast growing trees. The Poplar plantation of a clone J – 105 (P.niger L. x P. maximowiczii Henry “Maxvier“) is found on a farmland on a property of a Forests of town Brno a.s. (Lesy města Brna a.s.) close to the forest service LS Deblín. This plantation was found in 2006 and the first harvest took place 2013/2014, for the first growth cycle. The production of a biomass for the second growth cycle was found on the base of an inventory and a destructive method of a sampler trees. The production was evaluated both as a dry biomass production and fresh biomass production for the whole plantation and then separately for the vegetations of 7 and 6 growth period of rotation which form this plantation. A total area of the plantation is 1 ha. In this work, the production for 2019 was also compared to the production in 2012/2013 in the thesis of Ing. O. Stuchlý – („Vyhodnocení plantáže RRD založené na zemědělské půdě v majetku Lesů města Brna, a.s. „). An economical appreciation was calculated for the biomass of a freshly cut plantation with 55 % of water content. In terms of results of production, a total dry biomass production in 2019 was 49,1 t/ha for the whole plantation, in other words, 7,52 t/ha/year. For the 7 years growth periods of rotation the production was 52,73 t/ha or 7,56 t/ha/year and for the 6 years growth periods of rotation the production was 44,9 t/ha or 7,49 t/ha/year. By the statistic test there was found no difference between these two increments. The weight of the biomass of the whole plantation right after the harvest would be 123 t/ha. If we count with the production for the 7 years growth period of rotation, the total biomass would be 128 t/ha and 117 t/ha for the 6 years respectively. A yiled of the fresh biomass would be 119 099 Kč/ha. Theoretically higher yield would mean a production for 7 years of growth period of rotation – 124 153 Kč/ha. The yield for 6 years of growth period of rotation would be 113 408 Kč/ha.
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Vliv zvýšené koncentrace CO2 a sucha na rychle rostoucí dřeviny
Vágner, Lukáš
The main objective of this study was to determine the effect of elevated CO2 and drought on growth of fast-growing trees, hence hybrids of poplar Populus nigra and Populus maximowiczii on experimental station Domanínek. These parameters were measured: photosynthesis, reflectance, fluorescence of chlorophyll and content of chlorophylls and flavonols. The results show a demonstrable effect of greater regulatory abilities stomatas at elevated CO2 concentration, which leads to greater efficiency of water use. Decisive influence on leaf area, specific leaf area and the dry weight has the effect of drought. However, for specific leaf area, contrary to expectations, there was an noticeable increase during drought period. In the case of other characteristics come to reduce them. By contrast specific leaf area slightly decreases at elevated CO2 concentration. Rate of photosynthesis increases with increasing concentrations of CO2, while the effect of drought dampens these characteristics and also reduces the chlorophyll content. Increasing concentration of CO2 during the experiment also leds to an increase in NDVI index, which shows increased chlorophyll content. The values of fluorescence at two concentrations of CO2 when exposed to drought stress differed minimally. The maximum quantum yield of photosystem II is slightly higher at elevated CO2 concentration. Overall, it can be summarized that in the short-term effect of drought stress in hybrid poplar, increased concentration of CO2 increases water use efficiency and thus to mitigate the impact of drought on photosynthetic parameters.
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Fast-growing trees as a renewable energy source
Žvaková, Veronika ; Půčková, Helena (referee) ; Kotlík, Josef (advisor)
This bachelor thesis is focused on biomass as a renewable energy sources. The main topic is fast growing trees and their effects on biological diversity, the local ecosystem and landscape ecology. Literature survey was conducted regarding using this kind of biomass in the Czech Republic. Thesis reviews technological methods of cultivation and treatment of fast growing trees.
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Hodnocení stavu a vývoje sukcese po lesním požáru na kalamitní holině v revíru Janov, LS Jeseník – Lesy ČR, s. p.
Kmínková, Michaela
This bachelor's thesis concern with the investigation of the state and development of the secondary succession after the forest fire, which occurred in 2018 on a calamitous clearcut in the area of Janov, LS Jeseník - LČR, s. p. with a size of 6.75 ha. The assessment method was to evaluate the data from the field survey on 5 test plots, where I determined the type of tree species and forest regeneration, given dendrometric parameters - height and accrue, representation of the tree floor, I also evaluated the damage of regeneration and the development of unwanted vegetation. These values were measured in circular plots with a number in the range of 25 – 33. The plots were located both at the site of the fire and outside of it, with and without fencing. Aspen (Populus tremula L.) was the most numerous tree species in the area under investigation, with the largest presence in the area of the fire with fencing. With the greatest increase in height, the willow (Salix caprea L.) dominated here. The most frequently occurring damage was bite and frost damage occurring on the fireground outside the fence. Therefore, fencing proved to be an effective protection against game in this locality. The area outside the fence and the fireground was covered the most with unwanted plants.
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Ekonomický přínos pěstování japonských topolů pro rodinný rozpočet
Umlášková, Pavla
This bachelor thesis deals with the issue of Japanese poplar as a representative of fast growing species. The first part describes characteristics of the clones grown in our region and production in the world as well as in the Czech Republic. In the second part is elaborated the technology of production from selection of land to its destruction. The following part contains evaluation of recorded costs of wood production and estimation of future expenses that have not yet been paid for. The thesis includes also estimation of the plantation yield and suggested variants of house heating with using the results obtained. In the final part there are mentioned methods for use of harvested wood mass.
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