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The climate change has an adverse impact on tree species and forest stands. Different tree species tolerance and changes in tree species composition are considered as one of the climate change consequences. The paper deals with assessment and comparison of tree species composition and basal area increment in mixed (spruce-fir-beech) stands, which were left to self-thinning during 45–55 years. The large-scale experimental basis of older thinning permanent research plots established, in the past, in mixed stands situated in the 5th and 6th altitudinal forest zone was used in the research. At the same time the detected changes were compared to long-range goal and tree species models specified for a given forest type. The results showed increased proportion of beech and sycamore maple contrary to decreased share of fir and spruce. At the same time, fir also recorded the highest percentage of loss by self-thinning. The comparison of the current tree species composition with the models showed slight differences in all areas in favour of spruce at the expense of beech. Similarly, the basal area increment of beech was the highest everywhere.
This study focuses on natural processes and their utilization in silviculture. Two pioneer stands with the presence of silver fir in the lower storey were studied – (1) Mokřinky and (2) Padělky. Both stands are located in the lower part of the Nízký Jeseník Mts. (Czech Republic) and represent the oak-beech vegetation zone, although the dominant commercial species for this region throughout the 20th century was Norway spruce. The stands are about 30 (1) and 35 (2) years old with a dominant heights of 20 m and 25 m, respectively. In order to analyse the stand structure, an inventory net of patches (10 m2 for the upper storey; 2 m2 for the regeneration storey) was established. European aspen, as the dominant pioneer species, makes up 56% and 74% of the size of the average basal area of 28.8 m2/ha at the site (2) and 28.3 m2/ha at the site (1), respectively. Silver fir makes up 73% and 65% of total regeneration at (1) with average density 50 385 pcs/ha, and (2) with average density 108 462 pcs/ha, respectively. The age of silver fir regeneration ranged from one to more than ten years. The factor limiting the regeneration success of silver fir and other species in both preparatory stands is a game browsing. Considering closer-to-nature silviculture, the regeneration of silver fir in preparatory stands should be long-term.
Although the ongoing global climate change elicits a shift in tree species composition along the vertical gradient, very extensive areas of pure Norway spruce [Picea abies (L.) Karst.] stands still occur out of their ecological optimum in the Czech Republic and Central Europe. Adaptive measures should be applied in these stands to promote productivity and stability. All measurements were performed in the 2018–2021 period on three permanent research plots located in the North-East part of Bohemia (Czech Republic). Based on the results, the most favourable way to increase solar radiation use efficiency expressed by canopy production index (CPI) and leaf area efficiency (LAE) is in-time heavy precommercial thinning application. The highest CPI and LAE values were observed in the Norway spruce stand after heavy pre-commercial thinning application (CPI = 2.00 and LAE = 1.59). In contrast, CPI = 1.26 and LAE = 0.99 were observed after the mild one, and CPI = 0.73 and LAE = 0.60 were reported in the control treatment with no silvicultural intervention. Overall, the presented results indicate a positive effect of heavy pre-commercial thinning on CPI and LAE in pure young Norway spruce stands. However, more effort should be devoted to studying the impact of different pre-commercial thinning intensities on solar radiation use efficacy across a broader gradient of site conditions, and future work should also be extended to other tree species.
The European hare (Lepus europaeus) is one of the farmland specialists inhabiting agroecosystems. It is particularly sensitive to negative changes in agricultural management and landscape homogenization. The quality of the environment affects not only the hare population dynamics but also the behaviour of individuals, which is reflected in the variation in home range sizes. Preliminary results of the GPS telemetry monitoring in the Czech Republic revealed significant differences in the home range size of hares in high-diversified farmland (18.62 ± 4.14 ha) and conventionally managed agroecosystems (129.96 ± 55.64 ha) during the spring. These results demonstrate that the hare can thrive in a relatively small area, provided there are sufficient food sources and suitable shelter opportunities. However, increasing the biodiversity of the landscape can benefit not only the European hare but also other wildlife including protected birds and animals, which can respond to positive changes in the agroecosystem.
Silver fir (Abies alba, Mill.) is threatened by many factors in Central Europe, among which bark beetles of the genus Pityokteines play an important role. To improve the silver fir conservation, it is essential to adopt appropriate management practices. For this reason, we studied the occurrence of Pityokteines bark beetles in four sites located in climatically different conditions. In each site, five WitaTrap 5-segment pheromone funnel traps were placed from early April to late September in both 2021 and 2022. Two species, P. spinidens and P. vorontzowi, were captured. P. vorontzowi was significantly more abundant at all sites. Individuals of both species were recorded in the traps mainly in the period of April–August. The most abundant occurrence of beetles was at the site Nižbor, which can be explained by regional climatic differences (lowest elevation, higher mean temperatures and lower mean precipitation). The differences between sites can be also explained by different methods of forest protection applied. The study confirmed the presence of Pityokteines bark beetles and their dependence on climatic characteristics and forest management.
Two different forest types at the pole stand growing stage were compared regarding their transpiration during the peak of the growing season: a pure, artificially established even-aged Norway spruce (Picea abies (L.) Karst.) pole stand and a pure, naturally regenerated silver birch (Betula pendula Roth) preparatory pole stand. Both sites were comparable, as evidenced by the non-significant differences between daily averages of potential evapotranspiration on both sites. Both forest stands had been managed in the past and were reduced to 1,800 and 900 trees/ha for Norway spruce and silver birch, respectively. The forest transpiration of the silver birch preparatory pole stand was significantly higher than that of the Norway spruce pole stand, representing a transpiration rate over 1.4 times higher. Over a 56-day period, the cumulative transpiration was 127 mm for the silver birch stand and 90 mm for the Norway spruce stand. When transpiration was correlated to the potential of transpiration for particular sites, it was found that the portion was over 71% for silver birch and 42% for Norway spruce stand, respectively. Significant correlation of transpiration with the potential of evapotranspiration was established for both forest types, with this relationship being more distinct for the Norway spruce stand, indicating that its transpiration rate is more under control.
In Carpathians, the tinder polypore Fomes fomentarius (L.) Fr. is a well-known fungus commonly classified as frequent wood decomposer typical of beech forest stands. It is one of the most common wood-decaying macrofungi influencing structural stability, biomechanical properties and tree vitality of beech (Fagus sylvatica L.). Until 2023, no published records of this polypore on Norway spruce Picea abies (L.) H. Karst. Were known from the Carpathian Mountains. In this paper we present the first occurrence of the F. fomentarius in the Těšín Silesia (Moravian-Silesian region) in the Czech Republic. It is reported from the forest edge of a Norway spruce stand near the village of Horní Lomná in Frýdek-Místek District, which is located in this range (41°35‘ N, 29°07‘ E). Data on occurrence on coniferous hosts throughout Europe including some unpublished data are summarized.
Forest soil moisture limits (hydrolimits) suggest variation in soil water availability for tree species. In this study, we focused on estimations of soil hydrolimits using multiple regression with grain size, Corg, pH/H2O and cation exchange capacity (CEC) in the overlays between forest site georelief and bedrock in the Czech Republic. The multiple regression parameters were optimized in a system of 615 pits from case studies in 32 natural forest areas during 2002–2020. Light anhydromorphic soils were characterized by a decrease in hydrolimits with a profile depth, while hydrolimit values were higher at greater depths in hydromorphic soils. The dependences of hydrolimits on the granularity and forest soil physico-chemical properties were closer in the subsurface horizons than in the top ones. Higher correlations suggested that the hydrolimit increase appears to be more easily achievable in subsurface soil horizons by stimulating variable contents of Corg and CEC. On the other hand, the dependence of hydrolimits on variable soil properties suggested sensitivity to environmental changes affecting ecosystems.