Obsah/Content: ZLV 1/2024
ZLV, 69, 2024, Issue 10 - 0.
Moericke traps are commonly used to monitor pests in agriculture and at the same time, they have gradually been applied in forestry. Therefore, four Moericke traps were placed in two fir stands (Valšovice, Czech Republic) to investigate the spectrum and intensity of aphidomorphic insects between 2019 and 2021. The traps were consistently positioned at a height of two meters in the monitored stands throughout the monitoring period. Each stand was evaluated separately, and their distribution differences were compared to the nearest Johnson-Taylor suction trap in the locality called Věrovany. A total of 400 samples were collected over three years, out of which 1,674 specimens belonging to 111 species or genera, classified into three families (Aphididae, Adelgidae, and Phylloxeridae), were analyzed. The eudominant species found in these stands was Phyllaphis fagi, while the dominant species was Mindarus abietinus. Additionally, 11 species or genera were identified as subdominant, 5 species as recedents, and the remaining species fell under the category of subrecessive. It means that the majority of the captured specimens was not from fir trees but from undergrowth, adjacent stands, or other woody species.
The state of upper horizons of forest soils under forest stand groups of silver fir (Abies alba Mill.) and Norway spruce (Picea abies /L./ Karst.) was compared in the same site conditions. The study was performed on the site characterized as oak-fir with Luzula nemorosa, soils were determined as Luvisols, altitude 420–440 m a.s.l. Upper soil horizons (L+F1, F2+H, Ah and B) were sampled in five replications, holorganic horizons quantitatively. The amount of surface humus as well as basic pedochemic characteristics were determined: pH, soil adsorption complex characteristics, exchangeable acidity, the content of total carbon and nitrogen, and content of total and plant available macronutrients. The cellulolytic potential of H and Ah horizons was determined in a laboratory experiment. Results confirmed only mild effects of silver fir on the soil chemistry: soil reaction, base saturation, and especially on nitrogen content and C/N ratio. Basic elements content was slightly affected as well. No visible effects of fir on the cellulolytic activity were detected. Silver fir, compared to Norway spruce, showed only minor soil improving function.
The article summarizes and discusses studies focused on the carbon stock in forest soils and the way it is affected by forestry operations with a focus on the Central European (Czech) region. In general, the methods enhancing forests´ vitality and stability are more important than the procedures aimed at carbon sequestration only, as the major risk for carbon stock in forest soils is represented by large-scale disturbances. Important factors that will influence the mitigation potential include the change of tree species composition, as the majority of forests in the Czech Republic is still represented by Norway spruce or Scots pine even-aged monocultures. Careful practices of logging and forest restoration are recommended, with minimal opening of the crown layer. The use of clear-cuts should be reserved mainly for afforestation of light-demanding tree species. Care should be taken of sustainable nutrients content in forest soils, as the soil quality plays substantial role in the future forest vitality, productivity and resilience. Forest protection and all measures preventing large-scale forest disturbances are of key importance for carbon sequestration.
Forest management documents related to the whole Czech Republic contain detailed information about the state of forest stands and tree species. A subset of the data was prepared for stands of Douglas-fir (Pseudotsuga menziesii; 46,929 records) and Norway spruce (Picea abies; 37,761 records from stands where Douglas-fir was also present). Growth models for both species were constructed in the form of simplified Korf ’s function. The data set was divided into subsets according to forest vegetation (altitudinal) zones (FAZ) and groups of edaphic categories. On acidic habitats, both tree species reached maximum growth rate in the 5th FAZ. However, on habitats affected by water this occurred in the 4th FAZ. In the model example at the age of 140 years, Douglas-fir shows an average of 4% higher stand volumes in comparison to Norway spruce, while the felling volume as part of thinning, or left in the stand to decay, is about 32% higher in Douglas-fir.
The aim of this paper was to assess the influence of the silvicultural system (clear-cut and shelterwood), species composition of forest stands, in relation to the fluctuation of raw wood prices, on the economic results of forest management. Model analyses were performed on the example of the conditions of the CZU Forests, specifically for the third forest vegetation zone, SLT 3K. The input to the model evaluation was: data on the growth and production of the investigated tree species in the given site conditions from growth tables, the costs of forestry measures were derived from standards, the assortment was carried out on the basis of assortment tables, the prices of assortments of raw wood were taken from the data of the Czech Statistical Office for 2015 and 2019. The synthetic result of the model evaluations was the gross profit of forest production per hectare and year. The results of the analysis prove the economic advantage and greater stability of the shelterwood silvicultural system, especially with regard to lower silvicultural costs, higher volume of timber production and mutual compensation of the decrease and increase in the prices of raw wood of the evaluated tree species.
The article focuses on the growth response of young stands of Douglas-fir and mixtures of Douglas-fir with Scots pine on nutrient-poor sites. The experiment was established in a seventeen-year-old naturally regenerated stands using a block design with two replications. The silvicultural intervention (thinning) involved reducing the number of trees to 1,800 per hectare in the stand without pine representation and reducing it to approximately 4,000 trees in the less mature stand in the mixture with pine. The results of a thirteen-year time series since the implementation of the initial thinning are presented. The diameter growth of Douglas-fir on these sites is significantly lower compared to Scots pine. Without thinning, Douglas-fir is gradually being displaced by Scots pine in the stand, leading to a decrease in its representation and basal area. The silvicultural intervention have positively influenced diameter increment and improved the static properties of the trees, as expressed by their height-diameter ratio (HDR). In the thinned plot without pine occurrence, it was even possible to temporarily reduce the HDR values of target Douglas-fir trees. In the thinned plot with pine competition, the rate of HDR increase was only reduced compared to the control.
Research, development and innovation are generally formulated as priority attributes of economic growth, competitiveness and, therefore, improvement of living standards and social conditions all over the world. According to the Czech Statistical Office, the main source of funding for research, development and innovation in the Czech Republic are domestic and foreign enterprises. The emergence and history of forestry research in the Czech Republic has a remarkable and deep tradition, enhanced by the longevity of natural and production processes in forestry, not least because of the accentuated social importance of forest and forestry functions. The paper focuses on the research and development activities of selected forestry companies in the Czech Republic. The analysis included the state enterprise Lesy České republiky (Forests of the Czech Republic, s.e.), enterprises in the position of so-called contractual partners (in the outsourcing business model) and companies carrying out management activities in municipal forests. The basic methodological approach was the analysis of publicly available information on research and development reported by the enterprises concerned as so-called non-financial information in their annual reports for the years 2014–2020, on the basis of Act No. 563/1991 Coll., on accounting.
In the period of ongoing global climate change, ecosystems, including Central European forests, face significant challenges such as summer droughts and heat waves, which increase the climate risks also for the European beech (Fagus sylvatica L.), an important and dominant broadleaved tree species in this region. This article provides a comprehensive review of current knowledge on the adaptation strategies of European beech in response to changing climatic conditions, highlighting its ecological demands, development of taxonomy, ecological and economic importance and exploring its resilience, growth characteristics, and challenges such as water regime, pests, diseases, and the impact of climate change. A key finding is that despite the various stressors affecting European beech, adaptive management and the use of mixed forest stands can significantly contribute to its conservation and sustainable use. The importance of integrating the genetic diversity and adaptive capacity of European beech into forestry practices is emphasised. The review of 203 studies highlights the need for further research focused on understanding the interactions between European beech and a changing climate in order to develop more effective strategies for its conservation and sustainable management in the future.