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The increasing global demand for energy and the negative environmental impacts of fossil fuel exploitation have driven interest in sustainable energy solutions, such as wood. The Russian Federation, as one of the world's largest pellet producers, has an opportunity to utilise pellets domestically. This study addresses the lack of publicly available life cycle assessment (LCA) studies on pellet production and utilisation in Russia, specifically examining the environmental impact of residential heat production from locally produced wood pellets. Utilising primary data from the Northwest region, the study follows ISO 14040 and 14044 standards and employs the ReCiPe 2016 (H) Midpoint v. 1.1 method to assess environmental impacts. The results indicate that the production of pellets is the dominant contributor to the global warming impact category, marine eutrophication, and fossil resource scarcity, while transportation has the least impact across all categories. Sensitivity analyses confirm the robustness of these findings, revealing that using natural gas for pellet drying increases emissions for global warming and fossil resource scarcity, and increasing transportation distance significantly raises emissions across all categories. The findings provide valuable insights for policymakers and stakeholders aiming to enhance the sustainability of similar bioenergy systems.

Soil nitrogen (N) cycling plays a pivotal role in forest ecosystem productivity and nutrient regulation. This review synthesises recent advances in understanding how forest management practices influence soil nitrogen cycling and highlights future research priorities for elucidating underlying mechanisms and optimising forest ecosystem functioning (Figure 1). Management interventions such as thinning, species composition adjustment, and understory vegetation control have been shown to affect N inputs and transformation pathways by modifying litter quality, microbial community structure, and N-cycling enzyme activities. However, current findings remain inconsistent, and mechanistic insights are still limited. Future research should focus on disentangling the multi-scale, multifactorial interactions through which forest management regulates soil N cycling. Integrative approaches that link molecular biology with ecosystem-level processes are needed to clarify the interplay among microbial dynamics, enzyme activity, root exudates, and soil physicochemical properties across spatial and temporal scales. In addition, research should explore how forest management affects community structure, litter inputs, soil aggregation, and subsurface biochemical processes to reveal the synergistic regulation of nitrogen cycling by biological, physical, and chemical drivers. Establishing long-term monitoring networks across a range of forest types and climatic regimes, combined with tools such as metagenomics, high-throughput sequencing, and stable isotope tracing, will enable the precise characterisation of key nitrogen-cycling genes and fluxes. In the context of global environmental change, it is also crucial to assess how forest management modulates the coupling of nitrogen, carbon, and water cycles and the resultant ecological feedbacks.

Global climate change (GCC) is putting increasing pressure on forest ecosystems, leading to more frequent disturbances such as pest outbreaks and other climate-related stressors, all of which threaten forest stability. This study examines how different technical water retention measures (infiltration pits) can enhance the resilience of European beech (Fagus sylvatica L.) to these climatic challenges, focusing on their impact on radial growth, sap flow, and acclimatisation to moisture conditions at two sites in Czechia (430–440 m a.s.l.). Three treatments were compared: a water infiltration pit under a culvert mouth, an infiltration pit without a culvert and a control plot without a technical solution. Results showed that maximum daily transpiration rates of beech ranged between 90–120 L per day. Air temperature had a stronger influence on beech radial growth than precipitation, particularly at the waterlogged sites. The lowest radial growth occurred in the treatment involving a water infiltration pit under a culvert mouth, while treatments with an infiltration pit without a culvert demonstrated notable seasonal stem shrinkage and swelling (tree water deficit – TWD), especially in early spring. On the other hand, no differences were found between the three treatments including the control variant in the maximum growth or the context of minimum TWD. In conclusion, these technical measures had limited or short-term effects on the growth and physiological processes of European beech. Despite the high costs of implementation, sap flow and dendrochronological measurements do not support the construction of infiltration pits as a means of improving water retention in forest ecosystems.

Wood density is a fundamental functional trait influencing ecological adaptation, hydraulic safety, and timber utilisation in temperate hardwoods. This study investigated variation in wood density (12% moisture) across mature stands of two economically and ecologically vital European oak species, sessile oak [Quercus petraea (Matt.) Liebl.] and English oak (Quercus robur L.), growing in their characteristic vegetation zones in the Czech Republic. We assessed wood density at two heights (at 1.3 m and at the crown base) across six trees per plot and examined its relationship with tree-ring width and height. Results demonstrated statistically significant interspecific differences, with Q. petraea consistently exhibiting higher wood density (721 kg·m⁻³) than Q. robur (662 kg·m⁻³) at 1.3 m. Q. petraea showed a statistically nonsignificant higher density of 710 kg·m⁻³ at the crown base and an overall average of 717 kg·m⁻³, while Q. robur had densities of 701 kg·m⁻³ and 669 kg·m⁻³, respectively. Radial density profiles revealed species-specific patterns, with Q. robur showing a more uniform density distribution than the pronounced pith-to-bark gradients observed in Q. petraea. Regression analysis indicated that tree-ring width explained only 12–13% of the variance in density, so other anatomical factors, such as latewood proportion and tree-ring structure (number and cell size), should be examined as anatomical drivers of wood-density variation.

In response to the decline of Central European spruce monocultures driven by various factors, the Demonstration Object of Reconstruction of Spruce Forests (DORS) was established in Husárik locality, Javorníky Mts., northwestern Slovakia. The area includes the Husárik trial site, where the applicability and efficiency of different artificial regeneration methods are studied. The trial was established on a 24-ha area cleared following the outbreak of spruce bark beetles in 2011. Its altitude is 800 m a.s.l., aspect NW, slope 30%, the soil is Ranker on the soft flysch sandstone bedrock. Our study covered 4 conifers – Norway spruce (spruce), European larch (larch), silver fir (fir), and Douglas fir (doug fir). Each species was regenerated using 4 different approaches: planting of commercial bareroot transplants (BR), planting of container transplants (CON), direct seeding (DS) and vegetative cell seeding using seed shelters (VCS). Results concerning the nine-year development of transplants and seedlings, along with the calculation of cost-efficiency, are presented. As to the species, BR and CON transplants of spruce and larch reached the best survival and height. The DS larch was the most cost-efficient method of establishment of a successfully established plantation (survival > 50%; stem height > 2/3 of the weed height; ratio of damaged individuals < 50%) with a total cost of 2 372 EUR·ha^–1. On the contrary, the slow initial growth of fir and Douglas fir and their extensive damage resulted in the incomparably higher cost of establishment of their successfully established plantation, such as 4 980 EUR·ha^–1 for five-years-old BR fir transplants. Our findings documented that current efforts related to the restoration of salvage-felled clearings remained difficult, especially in the case of introduction or reestablishment of coniferous tree species more vulnerable to open site conditions.

Grey poplar (Populus × canescens) is a natural hybrid of white poplar (Populus alba L.) and Eurasian aspen (Populus tremula L.). It could play a significant role in the afforestation of marginal sites which stretch out on ever more areas due to the negative effects of local climate change. Based on stand structure analyses of grey poplar stands grown on the sandy sites of Hungary, the following relations were found: There is a strong relationship between tree height and stand volume (R² = 0.7256), as well as between basal area per ha and stand volume (R² = 0.9158). There is a moderate relationship between diameter at breast height and stand volume (R² = 0.6175). The results could contribute to a more accurate assessment of applied silvicultural technologies.

The environment is characterised by subtle and major mutations that cause changes in land use/land cover. Analysis of its dynamics and identification of vulnerable areas are critical to maintaining ecosystem services. The aim of this research is to quantify and qualify land cover dynamics over a 30-year period. It will also highlight forest degradation from a supervised classification of Landsat satellite imagery (L5 TM1987, L7 ETM+ 2000, and L8 OLI/TIRS 2019). The dynamics of land use/land cover were investigated by a maximum likelihood approach using geographic information system (GIS) and remote sensing (RS). Six major land use and land cover (LULC) types were mapped (build-up, agriculture, forest, clearing, matorral and olive cultivation). The classification reports made it possible to assess a reduction in forest cover (from 14 470.11 ha to 5 203.26 ha) and an increase in buildings (from 6 033.69 ha to 9 515.61 ha), and agricultural land (from 9 517.59 ha to 12 338.19 ha). The results were validated by a kappa coefficient of 0.93, 0.91, and 0.96, which showed that the model had successfully predicted LULC changes. We anticipate that the results will provide a basis for decision-making as well as a starting point for further in-depth studies in sustainable management and development of natural resources in the study region.

Frankincense trees (Boswellia spp.) worldwide are affected by a number of threats, including global warming and changing land management practices. On the Socotra Archipelago (Yemen), which harbours eleven endemic Boswellia species, grazing is generally assumed to be one of the main threats preventing natural regeneration. To test the impact of overgrazing on natural regeneration, we established an in situ experiment on four different Boswellia taxa in different areas of Socotra Island. Mortality and the height increment of seedlings were measured for a period of two/three years in five plots excluded from grazing (fenced) and in five paired control (unfenced) plots. Each plot was 50 m × 50 m in size and contained several adult trees as a source of viable seeds. Our results show that seedling mortality was significantly higher, and seedling height increment generally (4 out of 5 sites) lower in open compared to fenced plots. In the fenced plots, the number of seedlings for all species reached up to 772, with 560 surviving seedlings. In comparison, the control plots reached up to 296 seedlings, with 176 seedlings surviving after 2–3 years. The results of our experimental study indicate that grazing directly threatens the natural regeneration of the endemic Boswellia on Socotra Island. However, seedling mortality remained relatively high inside the exclosures as well, which indicates that even without the pressure of livestock grazing, other impacts remain a challenge for the future conservation of the archipelago's unique frankincense trees.

Riparian vegetation plays a major role in maintaining biodiversity and reducing the negative impact of nutrient leaching into aquatic ecosystems. However, the knowledge on the interactions between riparian vegetation and other environmental factors is still incomplete for planning sustainable riparian forest management. The aim of this study was to explore interactions between riparian forest ecosystem components along a small stream. Interactions between vegetation structure, chemical composition of soil and groundwater, as well as chemical element flows via litterfall and precipitation were studied in seven 50 m long transects located in the riparian forest of different characteristics along a 1.4 km river section in the northern part of Latvia. Our results showed that throughfall input of total nitrogen (TN) and potassium (K) was higher in transects with predominantly deciduous tree stands, but the concentration of TN in forest floor was higher in coniferous tree stands. At some soil layers, a positive correlation between organic soil carbon (OC) and the concentration of TN in groundwater was detected. The concentration of TN and nitrate-nitrogen (N-NO₃^–) in groundwater correlated positively with the deciduous tree basal area. The obtained results suggested that element flows are strongly dependent on tree species' composition and a comparatively small riparian area is able to provide diverse ecological conditions.

The primary objective of this paper was to compare the nutrient content (N, Ca, S, K, P, Mg) of bilberry biomass, both aboveground and underground, growing in different habitats along the altitudinal gradient. The research was conducted in protected areas of the High Tatras National Park (Slovakia). Two different habitats subjected to study, namely spruce forest stands affected by disturbances (D – disturbed forest stands) and stands unaffected by disturbances (U – undisturbed forest stands), were located at different altitudes: 1 100 m a.s.l., 1 250 m a.s.l., and 1 400 m a.s.l. We found significant differences in the soil nutrient content along the altitudinal gradient. The highest content of nutrients was detected mostly at the highest altitudes in both habitats. The minimum reached 0.01 g·kg^–1 (phosphorus), while the maximum was 8.33 g·kg^–1 (nitrogen). In the case of the bilberry biomass, we found statistically non-significant differences in the content of nutrients among the altitudes within both habitats (D vs. U). The principal component analysis (PCA) showed that the aboveground biomass of bilberry had a significantly higher nutrient content compared to the underground biomass. Nutrient content in aboveground and underground biomass ranged from 1.00 g·kg^–1 (phosphorus) to 13.49 g·kg^–1 (nitrogen) and from 0.38 g·kg^–1 (magnesium) to 7.55 g·kg^–1 (nitrogen), respectively. The biological absorption coefficient (element content in dry biomass/element content in soil) reached the highest values mostly at the lowest altitude for both aboveground and underground biomass.

Missouri Ozark woodlands are a unique, but imperilled ecosystem type due to fragmentation, lack of proper management and a changing climate. The management, restoration, and conservation of Ozark woodlands is a conservation priority. The Ozark woodlands contribute to the sequestration of carbon and nutrients through their robust productivity, effectively removing carbon dioxide from the atmosphere and storing it in the biomass and soil while cycling essential nutrients to support the ecosystem's health and vitality. We have assessed the over- and mid-storey leaf production, collecting leaves in baskets every autumn in a 1 200-ha conservation area in southwest Missouri since 2000. The leaf production data from 2000 to 2021 were compared among sites; control (not burnt for over 80 years), burnt (fire resumed in March of 1999 and repeated in 2001, 2003, 2008, 2010, 2013, and 2021) and reference (fire resumed in 1980 and repeated every 2 years). The average oak leaf production was statistically higher in the burnt site than the reference site, but only marginally higher than the control site. The leaf production varies statistically between the years. We applied a regression analysis among the productivity, temperature, and precipitation to associate the temporal variability in the weather with the productivity. The reference woodland showed statistical significance with the precipitation, but not with the temperature, while the other sites did not show any statistical significance with the precipitation. No statistically significance difference was observed between the productivity and temperature across any of the woodland burn histories. The March–June, March–May, and June–August precipitation statistically predicted the productivity. The results indicate that long-term burning is predictably associated with woodland leaf production and precipitation, but the precipitation is uncoupled with the productivity in woodlands that were more recently burnt or where burning has been suppressed. Sassafras saplings of approximately 1 m in height have emerged as the dominant species in the understorey of burnt woodlands while being completely absent from the control and reference woodlands. However, the productivity is the highest in the woodlands where burning has been suppressed and 20 years of prescribed fire does not significantly reduce the productivity. Oak regeneration over 20 years of burning is being suppressed by competition with sassafras, which may result in a significant shift in the ecosystem variables.

Long-term human activities substantially altered floodplain regions of temperate Europe. Forest management and extensive changes in hydrology greatly affected natural floodplain soil properties, in which microbes play key roles. This study aims to assess the effects of human activities through a gradient of forest management intensity on soil microbial community (SMC), its biomass, activity, and structure. Soil chemical and physical-chemical properties were used to explain the general associations and within-site variation using principal component analysis (PCA), linear regression (LR) and linear mixed-effect regression (LMER) models. It was found that forest management application, regardless of its intensity, led to significant microbial biomass reduction. PCA revealed that microbial biomass, expressed as a sum of phospholipid fatty acids along with recalcitrant carbon fraction (ROC) best explained the variability in data. LR and LMER highlighted that bacteria are affected by floodplain forest management more than fungi, and that bacterial response to pH was highly diversified. Also, pH was identified as the best predictor of SMC structure and activity but not of its size. The study calls for further investigation in SMC interactions with ROC, soil-available Fe and Mn, and the role of redox-active metals in soil organic carbon degradation.

Assimilation (A) and photosystem II (PSII) efficiency value light response curves [A/PPFD and PSII/PPFD curves (PPFD – photosynthetic photon flux density)] of promising black locust clones (NK2 and PL251) and the registered Üllői clone were analysed to study the net assimilation rates and PSII efficiency within the function of PPFD levels. The natural logarithmic regression functions fitted well to the measured data points for A/PPFD, R² values varied between 0.9515–0.9884. For PSII/PPFD values, we used the exponential regression function with R² ranging from 0.9948 to 0.9989. Except for PL251, the A/PPFD curves of the tested clones increased steadily with increasing illumination levels but flattened at the 600 µmol·m^–2·s^–1 PPFD level due to the effect of photorespiration on the assimilation rate. For PL251, the A/PPFD curve decreased at the 1 200 µmol·m^–2·s^–1 PPFD level. Unlike A/PPFD results, the PSII/PPFD exponential curve decreased as the PPFD level increased. Europe is forecast to experience significant negative climate change factors, including increased drought, heat, and irregular precipitation. Under such conditions, relatively drought-tolerant tree species such as black locust will play a vital role in new afforestation and uninterrupted wood supply. Consequently, growing and improving newly bred black locust clones, including the ecophysiological studies of relatively drought-tolerant clones, is increasingly vital.

This review article summarises the results of research on forest liming, fertilisation, nutrition flows and cycles in selected European and other countries. The presented studies mostly deal with assessing the effect of liming and fertilisation applied during planting or shortly after planting. The sporadic studies on fertilisation in older stands are also presented. The application of crushed limestone, dolomite or other alkaline rocks or their mixtures is usually used to improve the soil conditions on a large area through the adjustment of soil acidity and to supply any deficient elements, especially calcium and magnesium. These amendments are typically used on naturally nutrient-poor soils or as a curative technique to neutralise the soil chemistry affected by anthropogenic acidification. Artificial fertilisers are usually applied on small spots to individual trees on the surface of the soil shortly after planting or into a planting hole during planting. The purpose is to give some initial support to young trees to better overcome the post-planting shock and to accelerate the height growth. Less frequently, artificial fertilisers are used on large areas of forest stands for the purpose of increasing stem growth. The methods and the extent of forest fertilisation substantially vary in individual countries and different time periods.

In forest protection, various types of trap systems are used against spruce bark beetles to treat the foci of infested areas. Traditionally, these include pheromone traps, treated trap trees, and recently also the application of Storanet insecticide nets used for the sanitation of infested wood (trees), which also serve as treated trap trees when pheromones are applied, and the Trinet P system, a variation to a treated trap tree – a tripod. On an aluminium tripod, there is a Storanet insecticide net baited with a pheromone dispenser similar to other types of trap systems. The sex ratio proves to be a significant aspect in the assessment of individual types of trap systems. It is more favourable to catch a larger number of female individuals given that they bear the future development of the population. With a higher number of captured male individuals, the number of females per one male in the insect gallery increases, and the population cannot be reduced sufficiently. The results show that all three types of measures can be characterised by a lower ratio of captured males (approximately 40%) and a higher representation of females (around 60%). Differences in individual types of trap systems are insignificant.

Tree volume is a characteristic used in many cases, such as determining fertility, habitat quality, growth size, allowable harvesting, and the principles of forest trade. It is imperative to develop methods that predict forest stand volume to obtain this extensive information quickly and cost-effectively. This study used supervised self-organising map (SSOM), multi-layer perceptron (MLP), and radial basis function (RBF) neural networks to predict forest stand volume based on physiography, topography, soil, and human factors. A sensitivity analysis method called the importance of prediction was used to determine how input variables influenced network output. First, the map of homogeneous units was prepared with ArcMap (Version 10.3.1, 2015) by combining digital layers to measure the tree's volume per hectare. Then, separate tree species in different diameter classes were measured in a circular grid of 200 m × 150 m, 0.1 ha of coverage, 3.3% sampling intensity, and a diameter at breast height (DBH) greater than 7.5 cm using systematic sampling on a homogeneous unit map in a regular random method. The neural network modelling results showed that SSOM, MLP, and RBF predicted forest stand volume most accurately according to physiography, topography, soil, and human factors. Furthermore, the sensitivity analysis results found that altitude above sea level, soil depth, and slope are the most influential input variables. In contrast, soil texture variables are the least effective at predicting forest stand volume.

Due to an increasing risk of further damage to forests, forest managers are considering introducing an alternative direction for their future development – via the cultivation of mixed forests. At middle altitudes in the Czech Republic, an oak-beech-linden stand is the most natural type, and we tried to answer three main questions: (i) How the various thinning types affect dendrometric parameters and quality of the stand; (ii) How long thinning works on this stand until it loses its effect; (iii) How the stand develops spontaneously after abandonment. This experiment was conducted at the Training Forest Enterprise in the Czech Republic in Drahanská vrchovina (highlands in central Moravia). In 1988, four plots were established in a 49-year-old stand where, in three of the plots, different types of thinning (crown, low and heavy crown) were performed, leaving one (reference plot) to develop naturally. The height, the height of the crown base and diameter at breast height (DBH) were measured, and the shape and quality of the trunk and crown were estimated on each tree. Measurements were carried out in 1989, 1994, 1999, 2005, 2010, 2015, and 2020. In the first 10 years, the DBH and height of the crown base did not show any differences, and the linden at the heavy crown plot outgrew the linden trees at the other plots in height. After these 10 years, the thickest linden, the tallest beech and linden, and the greatest height of the crown base of beech and linden were all found at the heavy crown plot. The shape and quality of the trunks and crowns of beech, oak and linden were similar in all plots (including the reference plot) during the entire experiment. After thinning, the plots were left to grow spontaneously. The heavy crown thinning removed a greater number of thicker trees at the middle level, thus supporting the trees growing in the lower part of the middle level and in the below level (i.e. the beech and linden). These trees then grew more quickly compared to the others, but their quality decreased, as did that of the others. Therefore, a forest left to grow and develop spontaneously is practically unusable for commercial purposes.

We compared the biological and economic effects of simultaneous artificial regeneration of mixtures of pioneers (birch – Betula pendula Roth or aspen – Populus tremula L.) and beech (Fagus sylvatica L.) with plots of monospecific beech. During the period of two years, the height of young beech trees, their mortality, and the regeneration cost were analysed in the following treatments: monospecific beech (9 000 pcs·ha⁻¹), monospecific beech (5 000 pcs·ha⁻¹), beech/birch (5 000/2 500 pcs·ha⁻¹) and beech/aspen (5 000/2 500 pcs·ha⁻¹). Four plots (differing in soil and altitude) were established in the region of the Czech Republic in autumn 2021. The positive biological effect of these pioneers was detected only in the treatments where the initial planting stock of the pioneers was substantially higher than in that of beech (on average 39 cm vs. 100 cm, respectively). However, the expenses of simultaneous regeneration were about 15% lower compared to plots with monospecific beech in densities like 9 000 pcs·ha⁻¹, and around 35% higher than in the monospecific beech plots with a density of 5 000 pcs·ha⁻¹.

In recent decades, the interest in searching for procedures and strategies to make energetic and economic use of residues from different industries has been an important part of the political agenda. There are several methods to determine the volume of residues from the forestry industry, but they are too time-consuming to apply. The objective of the present study was to establish a simpler and more efficient method to quantify the volume of residues from the forest industry. Ten controlled piles were made with residues from a private sawmill in the city of Durango, Mexico. To calculate the volume, two manual methods and one automatic method were used to calculate the stacking coefficient of the piles, while the water immersion method was used to calculate the real volume. A completely random experimental design was used for the analysis, where an analysis of variance and mean comparisons were performed at a significance level of P ≤ 0.05. The results of the study show that the threshold segmentation method is faster, more practical and efficient than the other methods used. The estimation of the volume of these residues will contribute to generating sustainable alternatives for the development and use of forest industry resources.

Mediterranean Quercus forests have great ecological importance but face numerous threats, including pests. The spongy moth, Lymantria dispar L., is a major oak defoliator across its geographical range and has a natural enemy complex that may control its population dynamics. This study aimed to investigate candidate predators (Coleoptera: Carabidae) and parasitoids (Hymenoptera: Encyrtidae, Ichneumonidae, Pteromalidae, Braconidae, Bethylidae, Ceraphronidae, Eulophidae, Eupelmidae and Trichogrammatidae; and Diptera: Tachinidae), for the control of L. dispar in two areas in Andalusia (Spain). We studied 10 Quercus stands (Q. suber, Q. ilex, and Q. pyrenaica), with different L. dispar infestation level. Insects were collected using pitfall and cross-vane traps, during the defoliator's larval period. Four genera comprised 92.2% of all the Carabidae predators found: Steropus Dejean (34.1%), Carabus L. (28.4%), Calathus Bonelli (15.9%), and Platyderus Stephens (13.8%); and four Hymenoptera families comprised 93.7% of the parasitoid specimens collected: Encyrtidae (61%), Ichneumonidae (17.5%), Pteromalidae (10.7%), and Braconidae (4.5%). Both the natural enemy assemblage composition and the abundance per tree varied between geographical areas, as well as between levels of defoliator infestation. The candidate enemy complex was markedly diverse and abundant in stands not infested by L. dispar, where no insecticides had been applied. Our results suggest the importance of generalist predators as natural enemies of L. dispar.

Sandy soils represent an extreme environment for tree growth. Traditionally, site preparation before planting involves removing logging residues (LRR) and ploughing. An alternative method is incorporating logging residues (LRI) into the topsoil which may enhance tree regeneration and seedling growth. The aim of this study was to assess whether and how different site preparation techniques affect soil physico-chemical and microbial properties over the long term. The study was performed in the Záhorská nížina lowland (Slovakia) in September 2020. Soil samples were taken in two 25-year-old Pinus sylvestris (L.) plantations along five soil profiles in each stand, down to a depth of 30 cm. Results showed a significant increase in carbon and nitrogen concentration and soil moisture in the LRI plot. However, soil pH and phosphorus content significantly decreased. No significant differences were observed in calcium, magnesium, and potassium concentrations between the differently treated plots. The LRI plot also exhibited a significant increase in microbial biomass carbon, N-mineralisation, and catalase activity. The results indicate that different mechanical site preparation methods may impact soil properties over the long term, likely through improved seedling survival and tree growth.

In Central Europe, the most important pioneer species are silver birch and European aspen. Changes in disturbance regime and an economic interest for this species have led to studies on this species and stands. Two naturally regenerated dense stands of birch (Betula pendula Roth – silver birch monoculture) and aspen (Populus tremula L. – European aspen monoculture) were selected from a Querceto – Fagetum mesotrophicum site to observe responses under the same conditions in Central Europe. Both stands regenerated after the allochthonous Norway spruce stands dieback at the site in 1999. Within a 10 m × 25 m transect established in both stands, the diameter at breast height (DBH) of all the trees was measured between 2015 and 2020. In addition, the height and position were recorded for all trees, and sample trees of both species were felled for biomass measurement. A higher volume production of aspen at the beginning (107.48/96.80 m³) and at the end of the experiment (178.32/143.08 m³) was accompanied with a lower above-ground wood biomass (WAB). The WAB of birch increased from 81.9 t·ha^–1 to 103.3 t·ha^–1 and aspen allocated 79.5 t·ha^–1 to 94.8 t·ha^–1 of biomass. The current annual increment of biomass for these stands was 4.3 t·ha^–1 and 3.1 t·ha^–1 in the age range of 17 to 22 years. The culmination of the volume increment has not yet occurred in any of the stands, but the mean annual increment of wood biomass has already been reached for both stands. Furthermore, the aspen stand tended to be more dynamic in terms of biomass allocation and mortality. Also, the lower self-tolerance of aspen confirmed our hypothesis: the two native pioneer species differ in their social behaviour within monospecific stands.

In Czechia, harvesters contributed 43% of the total annual timber production in 2022. It is assumed that harvester technology will continue to be used intensively in the future, even though there is a change in the tree species composition of forests after the recent bark beetle outbreak and an increase in the use of close-to-nature forest management. The aim of this study was to analyse the over- and under-bark volume estimates of European larch timber produced by a harvester in Czechia. This study used the M3s price category for volume estimation. This volume was compared with the M3toDE price category. The M3toDE price category underestimated the over-bark volume by 5.59% compared to the M3s price category. However, for use in forestry practice in Czechia it is currently necessary to use the M3toDE price category. Therefore, the M3toDE price category was used to compare under-bark volumes according to different bark deduction methods. Differences were found between all the five methods investigated. Understanding this sub-issue will help in training operators, acquiring comprehensive knowledge about the functioning of harvester software and maximising the economic effect of the sale of larch timber.

Sri Lanka, as a developing tropical country, faces serious environmental challenges. Forests, as important ecosystems of Sri Lanka, are under pressure from intensive human activities and climate change. Invasive species represent a great hazard to autochthonous plant species and ecosystems, which are, at the same time, hosts to extraordinarily high biodiversity, of which a high percentage is endemic. In this paper, we reviewed the most challenging environmental problems of Sri Lanka and suggested the improvement of a number of them through silvicultural measures and cooperation with international experts, namely Czech foresters. We also reviewed the main forest biomes and addressed the specific problems and management of different forest types.

The objective of the presented research was to create an average image of a harvester operator in Poland and to identify factors influencing the degree of mental workload. We used a survey of environmental assessments of workload. The creation of an electronic survey and the support of a company that indirectly employs operators (State Forests) made it possible to reach a large group of surveyed people. The respondents indicated the occurrence of ailments typical of sedentary work at the researched workstation. These included mainly monotony, back pain and numbness in the upper limbs. Stress at work was felt by the majority of respondents; hence the analyses of mental stress, which also translates into other diseases, should indicate key responses to questions regarding comprehensive ergonomic assessments at the researched workstation.

This paper examines changes in soil physical and chemical properties in relation to tree proximity on different slopes. Topsoil and subsoil were sampled at 12 research plots on four slope types, the soil pits being placed at the base of a tree (near tree, NT) and between the test tree and an adjacent tree (between trees, BT). We observed a significant decrease in vertical topsoil response to slope on lower, middle and upper slopes, and a decrease in fine roots (R < 2 mm) on flat ground. Overall, middle and lower slopes showed the highest similarity, and upper slopes and flat ground the least, with the greatest subsoil changes observed mainly on middle slopes and least on lower slopes. There was clear topographic dependence between subsoil water stable aggregates (WSA) and C dynamics, with BT total carbon (Ctot) higher on flat ground and lower on middle slopes; unlike topsoil, where the strongest WSA correlation was with distance from the tree. The highest N : OM (organic matter) ratios occurred on middle slopes facing north-west, and lowest on lower slopes facing north and flat ground. Our findings confirm the influence of slope type on soil characteristics, with NT soil supporting soil formation by transporting water to deeper layers, especially on slopes > 5°. These observations contribute to a better understanding of the dependence of soil properties on slope type and tree position when planning sustainable forest management.

Afforestation of agriculturally used land has many benefits which are described in different publications. As stated in these publications, afforestation of agricultural land can influence soil water content because of rainfall interception and concentration, transpiration, and properties of forest floor layer and soil; also, hydraulic lift may occur. In this study, we attempted to find changes in volumetric soil water content values (at depths of 20 cm, 40 cm, and 60 cm) on agriculturally used land afforested with a mixture of forest tree species (Quercus robur L., Quercus rubra L., and Acer platanoides L.) or Pinus sylvestris L. in the year 2011 (and on agriculturally used land = control). This study was performed in the period from the end of March 2021 to the beginning of April 2022. In this study, we proved our hypothesis on the reduction of volumetric soil water content after afforestation; it is probably because of higher rainfall interception and evapotranspiration as described in different studies. Concerning the afforestation, the average volumetric water content was higher on the plot afforested with broadleaves compared with Scots pine. It was especially in the period after defoliation when the proportion of throughfall (and stemflow) increased on the plot with broadleaves. Our results indicate a higher water-storage capacity of forests compared with agriculturally used land. During the leafless period, this capacity was found to be higher after afforestation with Scots pine.

Increasing the proportion of broadleaved trees in stands during regeneration raises questions about how these trees will be reflected in the economics of forest owners and whether these owners can influence certain economic aspects during stand management. In this respect, the paper focuses mainly on the revenue side of forestry and, crucially, analyses the selling prices of assortments of tree species groups as offered in public tenders of state forests under the outsourcing business model. The price level of spruce is used as a benchmark for comparisons in the analyses. It is clear that the cultivation of species-diverse forests entails an increase in the representation of a higher number of tree species and, presumably, increased stand stability. However, a concomitant consequence may be an increase in costs and a reduction in returns for forest owners. Here, the revenue from timber sales can be improved by appropriate adjustment of the species composition through educational interventions. All this is in the context of the economic viability of forestry, as declared in a number of strategic and forest policy documents, which essentially depends on the timber production function of forestry and the subsequent processing of timber.

Owing to its role in mitigating CO₂ in the atmosphere, the total organic carbon (TOC) stock of soil, a key component of the terrestrial carbon cycle, is of significant interest as regards climate change. To determine TOC stock, it is first necessary to determine the soil's bulk density (BD), determined through intact soil sampling; however, in forest soils, it can be difficult to determine BD in soils with high levels of stoniness and/or tree root coverage. Furthermore, the method is time-consuming and labour-intensive, making it impractical for studies over large areas. In such cases, BD can be determined using a pedotransfer function (PTF) expressing the relationship between forest soil TOC and BD. The aim of this study was to determine a forest soil PTF using actual data obtained from 777 soil pits dug as part of the Czech Republic's National Forest Inventory (NFI). Within the NFI, BD is assessed from undisturbed core samples, while TOC is assessed from mixed samples from the same soil genetic horizons. Both generalised linear (GLM) and generalised linear mixed-effects (GLMER) models were used, with the final GLMER model best expressing the relationship for individual natural forest areas within the NFI dataset. The GLMER-based PTF described in this study can be widely applied to accurately estimate soil BD via TOC concentration at temperate forest sites where stoniness and/or root cover previously made it technically impossible to take undisturbed samples using standard methods.

Lymantria dispar, a well-known defoliating pest species, also presents a health challenge due to the allergenic potential of its hairs, making it interesting to study from various perspectives. As chemical control methods decline in popularity, the search for effective natural enemies of this pest, such as predators, parasites and parasitoids, are expanding. On this occasion, we report the discovery of the primary parasitoid Glyptapanteles liparidis and the secondary parasitoid Gelis areator for the fauna of Slovenia. Illustrations and a short biology are given for both species.