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Srovnání stavby, chemického složení a trvanlivosti různých druhů dubu
Šorejs, Karel
This bachelor's thesis examines the average widths of annual rings, the percentage of summer wood, the amount of extractive and phenolic substances, the loss of wood mass by Trametes versicolor and the mutual relations between the resulting values. The samples evaluated in this thesis were of Quercus alba, Quercus petraea and Quercus robur. It was found that the least durable species was Quercus alba, which showed the widest average widths of the annual ring, the highest percentage of summer wood and the lowest content of both extractive and phenolic substances. Quercus petraea and Quercus robur showed very similar contents of extractive and phenolic substances and the average width of their annual rings with the percentage of summer wood, but they showed differences in the loss of wood mass – Quercus petraea at 4.64 %, and Quercus robur at 8.41 %. The annual ring width and the percentage of summer wood on the content of extractive and phenolic substances showed dependence. Thus, with decreasing annual ring width and increasing summer wood diameter, the content of both extractive and phenolic substances increases. Furthermore, the fact that the content of phenolic substances significantly affects the resulting durability of wood, i.e. with increasing content of phenolic substances, its durability also increases.
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Jarní aspekt korunové fauny v lesních porostech s výskytem chrousta maďalového (Melolontha hippocastani Fabr.)
Švaříček, Tomáš
The aim of this Master’s Thesis is to evaluate the changes of spring aspect of the crown fauna of invertebrates in the year of swarming of the forest cockchafer (2019) and in the years without swarming, in the gradational area in the forest area belonging to administration of Buchlovice, the forest district of Bzenec. In the second gradational area of the forest cockchafer, belonging to administration of Brandýs nad Labem – forest district Býchory, was the aim to evaluate the changes of the crown fauna of Quercus petraea, Quercus rubra before and after application of different kinds and concentrations of chemical substances (Neem Azal, sulfate Mn, chloride Mn, Mospilan) in the year of swarming (2020). The observation was realized by the method of shedding the fauna from the crowns to tarps on selected forest covers and wooded plants (Quercus robur, Quercus petraea, Pinus sylvestris, Fagus sylvatica, Betula pendula, Robinia pseudoacacia, Alnus glutinosa, Carpinus betulus, Tilia spp.) fortnightly in the spring period sampling 150 pieces of invertebrates in the forest district of Bzenec and 50 pieces of non-target component in the forest district of Býchory. Each sample was conserved in 75% ethanol solution and then sorted to the family or, with a cooperation of a specialist, determined to concrete species. In 2019, the forest cockchafer was swarming in the forest district of Bzenec, the percentage of this species was 46,8 %. The phytophagous component was dominant in the overall representation with occurrence of 67,9 %. The year after (2020), the forest cockchafer was swarming in the forest district of Býchory, where chosen spraying substances were applied. Spraying substance Mospilan 20 SP 24 g appraised to be the most effective one. From the non-target component of the crown fauna were most numerous the families of Araneae, Curculionidae, Elateridae a Heteroptera. In 2020, species Pseudeuparius sepicola (F., 1792) and Acallocrates colonnellii (B., 2003), from the Red List of Threatened Species of the Czech Republic, were identified in the forest district of Bzenec.
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Response of Soil Respiration, Temperature and Moisture to the Harvest of a Sessile Oak Forest\n
Dařenová, Eva
Forest management, particularly thinning and harvesting measures, has a significant impact on the forest carbon balance. In this study, we investigated the effect of the harvest of a sessile oak forest on soil respiration as a main source of CO2 emissions in forest ecosystems. Soil respiration, temperature and moisture were measured during the two growing seasons, one before and one after the harvest applied on six out of nine studied plots in April 2018. The harvest increased soil temperature by up to 6 °C. Soil moisture did not differ between the plots in 2017, but it was higher in the harvested plots compared to the control in 2018. In the first half of the growing season 2018, the difference between the control and harvested plots ranged between 5 and 100 % in proportion while in the second half the differences decreased only up to 5%. Soil respiration ranged between 1.2 and 3.3 µmol CO2 m-2s-1 during 2017 with no difference between the following variants. In 2018, soil respiration ranged between 1.2 and 7.0 µmol CO2 m-2s-1 and it tended to be higher in the harvested plots compared to the control. The exception was observed shortly after heavy rainfall on 5th September when soil respiration in the control significantly exceeded that in the harvested plots.
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Haplotyping of oak populations by chloroplast sequencing reveals origin and homogeneity of populations
Vlasák, Josef ; Cvrčková, H. ; Máchová, P.
The aim of this publication is to present new method of DNA isolation from young\noak leaves that enables efficient amplification of trnD-trnT region of chloroplast\nDNA and direct sequencing of crude PCR reaction mixture. Sequence data of trnDtrnT region have been used to examine Quercus robur and Q. petraea populations variability. High discrimination power of this method is demonstrated, comparable with previously used restriction analysis of four similar chloroplast DNA regions. Variable positions in trnT-trnD chloroplast DNA fragment are mapped and their use for oak haplotyping indicated. As an example, 20 Czech Republic oak populations were analyzed and their history, geografical origin and homo/heterogeneity were revealed.
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