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Qualitative evaluation of production and qualitative increment in stands at forest district Klokočná
Švec, Otakar ; Remeš, Jiří (advisor) ; Pulkrab, Karel (referee)
This thesis investigates the production and economic characteristics of forest stands in transformation process from even-aged forest stands to irregular forest stands. In the research area of Forest District Klokočná originally pure pine (Pinus sylvestris L.) and spruce (Picea abies L.) stands are being transformed to stands with complex forest structure characterized by selection harvest with the purpose of production and struc-tural equilibrium. Data was collected from eighteen 0.25 ha study plots; nine of them on forest develop-ment type (FDP) A -- acidic forest sites (predominantly 3K - Querceto-Fagetum aci-dophilum) and nine on FDP B -- waterlogged forest sites (predominantly 4P - Querce-to-Abietum variohumidum acidophilum). Within each study plot all woody stems of diameter more than 10 cm were measured. For each stem, the diameter in mm at 1.3 m above ground (dbh), the total height and the crown height (hypsometer Vertex, accuracy 0.1 m) were measured. For selected trees in particular diameter classes increment cores were sampled. For each FDP and stand structural segment a set of trees was sampled before and after the harvest and local assortment tables were crated for spruce and pine. Based on sampled data, financial value of standing timber, annual value incre-ment and target diameter for spruce and pine were calculated. Based on research results it is shown that lower homogeneity of forest stands has led to higher diameter increment of individual trees. On the contrary, negative effect of higher structural complexity of forest stands is lower quality of spruce timber in the range of 3 -- 4% per 1 m3. Generally better quality of pine and spruce timber, and thus also higher value, was confirmed for the FDP A. In this FDP target diameters for both investigated tree species are 8 -- 13 cm higher than for FDP B. It is concluded that forest transformation has strong impact on the production and eco-nomic characteristics of forest stands in the Forest District Klokočná, nevertheless studied forest stands still cannot be considered as stands with ideal selection structure in production and economic optimum. For future transformation efforts model charac-teristics differentiated according to site and structural characteristics are needed.
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@Potential of brassinosteroids for forest seed and nursery management and for forest regeneration@
Bach, Petr ; Kuneš, Ivan (advisor) ; Švec, Otakar (referee)
Brassinosteroids (BRs) are a class of polyhydroxysteroids that have been recognized as a sixth class of plant hormones. In specific conditions BRs can positively influence the plant growth and development. The first isolated brassinosteroid was natural Brassinolide from rapeseed (Brassica napus L.). Recently BRs are extracted primarily synthetically; they are effective even in very low concentrations. Several studies of different plant species show positive influence of BRs on growth, flowering, germination and resistance to stress factors. Existing scientific studies that deal with BRs impact on plants were predominantly applied on agricultural crops. Until presence, the similar research in forest seed treatment and forest nursery was almost missing. In the Czech Republic the Department of Silviculture of the Faculty of Forestry and Wood Sciences of the Czech University of Life Sciences Prague newly started to deal with the use of BRs in forestry. The aim of this master thesis is to elaborate literature review on BRs and to summarize existing research of their impact on plants. Second part of the thesis solves influence of BRs on Scots pine (Pinus silvestris) seeds germination. Tests are performed in normal and in stress conditions. Results of the practical part show that BRs affect positively seed germination in normal conditions; seeds treated with BRs show higher germination rate than control seeds. Positive impact was not registered when the seeds were exposed to stress factor -- heat. Any research paper showing significant positive influence on forest seedlings in Central European conditions was not published yet.
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