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This article presents guidelines for assessing the optimal dimensions of forest road pipe culverts, based on input of actual and experimental data to standard engineering techniques. In doing so, we assess the need for (i) changes in the parametrisation of inputs (i.e. culvert micro-catchment dimensions, rainfall and resultant culvert flow, and culvert flow rates during culvert hydraulic dimensioning), and (ii) the need to redesign culvert outlets in relation to flow speed. Our results demonstrate that values for most inputs presently used under current technical practice for forest road pipe culvert sizing are significantly higher than those achieved under experimental conditions. The data on outlet flow velocities strongly suggests that strengthening of culvert outlet aprons will be crucial for their future operation.

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.

Volume models are essential tools for quantifying timber stocks and optimising forest utilisation. This study aimed to develop additive volume systems based on one- and two-entry simultaneous equations for Pinus ayacahuite Ehrenb. ex Schltdl. and Pinus douglasiana Martínez. Destructive sampling of 55 P. ayacahuite trees and 65 P. douglasiana trees was conducted in the communal forest of Ixtlán de Juárez, Oaxaca, southern Mexico. The additive systems were fitted using non-linear seemingly unrelated regression to estimate tree-volume components: stem and branch volumes, with whole-tree volume being the sum of both. The systems were evaluated using the relative ranking method, considering statistical indicators of accuracy, variability, and relative errors. Additionally, the predictive capacity of the equations was assessed through linear regression between observed and predicted values for each volume component, and the biological consistency was verified. The results indicate that two-entry additive systems provide greater accuracy in estimating stem, branch, and whole-tree volumes for both species. These equations are based on the Schumacher-Hall model, and their recommended range of application for both species is for diameter at breast height (DBH) between 9 cm and 75 cm, and for total height (H) between 9 m and 34 m. Therefore, their application is recommended for forest inventories and the planning of sustainable forest management.

National parks (NP) are the last refugia of forests dominated by the Nothofagus species in Chile. However, frequent, careless human-caused fires are destroying these forests even within the national parks. After large-scale fires, N. pumilio stands are unable to recover naturally neither in generative nor in vegetative ways and artificial regeneration must be resorted to in order to maintain their extent. However, even artificial regeneration is not successful without protection against browsing. Therefore, the aim of this study was to experimentally test a range of repellents and other methods of mechanical protection of seedlings against browsing. Five replicates of plots were placed in Torres del Paine NP, in different habitat conditions and with different methods of protection against browsing (11 repellents, wire mesh, plastic tube and control). In each plot, 12 seedlings were treated with each type of protection. In our experiment, only 8% of the seedlings were damaged by browsing, while the mortality rate was 38%. The results indicate a more significant effect of abiotic factors (mainly frost, drought or wind) on seedling mortality than browsing. In parallel, however, it is clear that, compared with the control, six of the eleven repellents used in the experiment showed a significantly positive effect. We suggest the use of plastic tubes as the best option to protect seedlings, which, in addition to providing 100% protection against browsing, are likely to provide more favourable microclimatic conditions for seedlings, similar to leaving the burned snags.

Scots pine (Pinus sylvestris L.) is one of the most widespread and economically important coniferous species in the Northern Hemisphere. However, its regeneration success has recently been increasingly affected by global climate change (GCC), particularly through increasing mortality. This research aimed to evaluate the early establishment success of 30 400 bare-root and containerised Scots pine seedlings and saplings of different height classes, planted at various times on acidic and gleyed sites (479–610 m a.s.l.) across four locations in the Czech Republic. On acidic sites, seedlings exhibited 16% higher height growth and 11% lower mortality compared to gleyed sites. Containerised planting stock achieved significantly (P < 0.05) greater height growth (by 83%) and lower mortality (by 36%) than bare-root stock. For containerised material, spring plantings showed superior growth and vitality compared to autumn plantings. Planting stock height class had a stronger influence on height growth than on mortality. Based on the results, planting containerised saplings of 26–35 cm or 36–50 cm height in April is recommended for optimal establishment success of Scots pine under GCC.

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.

A lack or, conversely, an excess of water during the first growing seasons can bring about a slowdown in the growth of plants, their stagnation or even death. The necessary amount of water is not known for most hybrids of Paulownia. Therefore, one species and four hybrids were subjected to three regimes of watering to find out their impacts on plant height, radial growth, the amount of leaf biomass and leaf area. We planted 30 plants of each species/hybrid into plant pots under a shelter. At the end of the growing season, we measured the above-mentioned parameters. Our results showed that: (i) generally, a mean precipitation of 50 mm per month in the growing season ('per month') seems to be insufficient for optimal growth of Paulownia plants in the first years after planting; (ii) each species/hybrid reacts differently to the amount of water – P. Shan Tong grows better with 100 mm per month, P. tomentosa with 150 mm (and more) per month and the growth parameters of the others did not change (and remained low) with different amounts of water (P. Hybrid 9502, P. Bellissia^® and P. Clon in vitro 112^®).

This study aimed to compare patterns in the genetic structure of 27 mature stands and the natural regeneration of A. alba in the Eastern and Western Carpathians within the introgression zone of two refugial lineages from the Apennine and Balkan peninsulas. The distribution of the genetic diversity of fir stands was analysed using paternally inherited chloroplast DNA and five nuclear dominant inter simple sequence repeat markers (ISSRs). The study showed that the Balkan haplotype prevailed in both parental and progeny populations, and this haplotype was found in many mature Eastern Carpathian stands. Relatively high levels of genetic diversity were found in the mature stands (effective number of alleles Ne = 1.517, Shannon index I = 0.436, expected heterozygosity He = 0.295) and progeny (Ne = 1.515, I = 0.436 and He = 0.294) of silver fir. The analysis of molecular variance (AMOVA) revealed slight differences among the mature fir stands from the Western and Eastern Carpathians, with a value of 1.1%. According to principal coordinates analysis (PCoA) and STRUCTURE analyses, the populations, including stands of mature and progeny trees, were genetically separated into two groups. Slight genetic differences between the mature and progeny populations in the Polish Carpathians indicate sound gene pool transmission, which is essential for creating new selection and breeding programmes.

The mechanical scarification of acorns, although requiring a significant investment of resources, is a process commonly used in container nurseries for seed preparation. Its aim is to increase the number of germinating seeds and to shorten and equalise the length of their germination period. Research results indicate that scarification also affects the production of seedlings with improved biometric parameters. However, there is limited information available on improving the structure of the root system, primarily due to the limited availability of image analysis systems for these plant parts. This study employed modern measurement methods using WinRhizo and WinFolia software (Regent Instruments Inc.; Version Pro, 2022) to comparatively analyse root system parameters, focusing mainly on their structure. The parameters of pedunculate oak (Quercus robur L.) seedlings grown in polystyrene containers were compared with and without mechanical scarification, achieved by manually cutting off part of the acorn. After the end of the growing season, the parameters of all analysed seedlings (200 pieces) were determined, and a detailed analysis of the root system was performed on selected average individuals (64 pieces). Scarification resulted in an increase in the number of germinated seeds and grown seedlings, as well as an increase in the height and diameter of the root collar and a reduction in the variation of the obtained seedlings' parameters. Seedlings grown from scarified seeds were also characterised by a greater number of leaves with larger unit mass, which had smaller dimensions. The root system of seedlings grown from scarified seeds exhibited a higher average diameter and total volume of roots, as well as greater total length, surface area, and volume of fine roots, i.e. in the diameter range: 0.5 < D ≤ 2.0 mm. The obtained results confirmed the positive effect of seed scarification on germination and emergence efficiency, as well as on biometric features and the quality of the grown seedlings.

Fine roots (≤ 2 mm in diameter) account for up to 50% of total net primary production in forests, representing a major flow of both carbon and nutrients into the soil. We investigated the vertical distribution and production of fine roots in a warm temperate old-growth evergreen broadleaved forest in southwestern Japan. We used a continuous inflow method that considered different rates of diameter-dependent root mortality, decomposition, and thickening. Fine roots were classified into two classes (≤ 1 mm and 1-2 mm diameter). The experiment was conducted over a 1-year period to collect data on the mass of live fine roots and mass of dead fine roots in January, May, November and the following January. Decomposition ratios were assessed for three intervals (January to May, May to November, and November to January). More than 70% of fine roots occurred in the 0-20 cm soil layer, and less than 4% were found in the 50-80 cm soil layer. Decomposition ratios varied seasonally in both root size classes, peaking in summer and reaching a minimum in winter. The same pattern was found for production, mortality, and decomposition. The peak rate of production was 1.62 g.m-2.day-1 in ≤ 1 mm and 0.63 g.m-2.day-1 in 1-2 mm fine roots. The lowest production was 0.62 g.m-2.day-1 in ≤ 1 mm and 0.38 g.m-2.day-1 in 1-2 mm fine roots. Total fine root production over a 1-year period was 6.61 t.ha-1. A mass of 2.70 t.ha-1yr-1 of dead fine roots was decomposed to return nutrients to the soil. It is concluded that a warm temperate old-growth evergreen broadleaved forest in southwestern Japan plays an important role in carbon cycle and nutrient return through a high amount of production and decomposition.

Forests important from a water-management perspective cover 723,000 ha of the Czech Republic (CR), i.e. 27.6% of the forest area. These forests play an important role especially in a mountain landscape. Forests decrease peak flood flows, compensate water discharge and represent a source of high-quality fresh water. The optimum hydrological function is provided by forests that are healthy, ecologically stable, diversified, proper to site, growing on a good forest soil, managed by small-area felling and emulating natural processes. For mountain sites of the CR, the optimum proportion of Norway spruce (+ Silver fir) ranges from 70 to 80% and of European beech from 20 to 30%. Clear-cuts due to air pollution disasters led to replacement of the forest stand by perennial grassland increasing stormflows and decreasing the soil water supply to groundwater resources and the quality of water discharged from the forest. Skidding and hauling operations and an improperly constructed and maintained road network increased the surface runoff from a forest. Intraskeletal erosion occurs on pollution-disaster stone fields and in dying forest stands on stony sites. Reforestation of stone fields is necessary for the preservation of forests on stony and bouldery localities and their services for the cultural landscape situated below. In mountain headwaters, torrent control and forest amelioration are of great importance. These decrease peak flood flows, compensate water discharge and reduce bed-load and sediment transport. Forest amelioration enables the reforestation of waterlogged pollution-disaster areas.

The year 2018 was distinguished by a warm summer with extended periods of low or no precipitation. In this context, we investigated the intra-annual dynamics of xylem differentiation phases and quantitative vessel anatomy to analyse the age effect on the xylem formation response of younger (50 years) and older (135 years) mature European beech trees under summer drought conditions. The xylem formation dynamics of young and old trees were performed on microcores collected at weekly intervals in the Rájec-Němčice ecological station in the South Moravia region (Czech Republic). The onset of xylem formation was found identical in both age trees, and most of the trees ceased their enlargement by the end of July, which is attributed to the harsh environmental conditions of this month. Young trees were characterised by a 10-day extended enlargement period and a higher growth rate, resulting in more vessels and a wider tree-ring width. No significant linkage was found between intra-annual environmental conditions of the 2018 year or age effect and the vessel anatomy traits.

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.

The forest certification is a voluntary programme to ensure that the timber harvested from forests is processed in a sustainable manner by following specific standards. The Programme for the Endorsement of Forest Certification (PEFC) was introduced in 1999 using the bottom-up approach, and it gives flexibility for a country to set up their own PEFC standard based on current practices in sustainable forest management (SFM), regulation, and governance. This practice has led to the development of various PEFC standards for each country; thus, the impact of PEFC certification differs from country to country. In accordance with that, this study aimed to evaluate the PEFC standard application in developed and developing countries, namely in Sweden and Malaysia. The study also analysed the impact of forest certification on governance and economic aspects within Asia Pacific and Europe. The outcome of this study indicates that the PEFC standards developed by these countries showed similarities; for example, both countries are focusing on social and environmental requirements. Meanwhile, the differences were shown in the criteria, terms used, and the focus area. The impact analysis exhibited that countries are facing similar issues, especially market access and premium prices. This study revealed that each country develops different standards based on current practices, forest diversification, and regulations.

The paper examines the impact of biotic factors – mainly pests and pathogens – on the degradation of Betula spp. in the forests of Ukrainian Polissia. The taxonomic structure of the identified mycobiota includes representatives of 9 genera, 8 families, 5 orders, 4 classes, and two divisions (Ascomycota 44.4%, Basidiomycota 55.6%). Xylotrophic Basidiomycetes, particularly Fomitopsis betulina and Fomes fomentarius, pose the greatest threat due to their ability to destroy wood tissues. The bacterial pathogen Lelliottia nimipressuralis, the agent of wetwood, also plays a major role, impairing xylem water transport and causing systemic physiological imbalance in affected trees. Entomofauna significantly contributes to degradation processes. A total of 31 insect species were recorded, belonging to five orders, 24 families, and 29 genera, with Coleoptera being the most numerous (32.3%). The most harmful are xylophagous species (e.g. Agrilus betuleti, Rhagium mordax) and phytophagous species (e.g. Geometra papilionaria, Parornix betulae), which cause mechanical tissue damage and facilitate secondary infections. The results indicate that pathogenic complexes intensify under environmental stress, accelerating the decline of Betula spp. stands. These findings underscore the necessity for ongoing phytosanitary monitoring and adaptive management measures to mitigate further degradation risks in the birch forests of Polissia.

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.

This study examines the floristic composition, structural attributes, diversity patterns, and distribution of endemic woody species along an altitudinal gradient in the Al-Jabal Al-Akhdar mountain of northeastern Libya. Stratified sampling was conducted across four elevation zones on the northern and southern slopes. Phytosociological parameters – including density, basal area, importance value index, and diversity indices – were assessed, and Pearson correlations were used to evaluate relationships with altitude and aspect. A total of 61 woody species from 43 genera and 26 families were recorded, highlighting the region's biodiversity. Tree and shrub density and basal area increased with elevation, particularly on northern slopes. Juniperus phoenicea L. emerged as the most dominant tree, while Phlomis floccosa D. Don and Pistacia lentiscus L. dominated the shrub layer. Diversity indices showed negative correlations with altitude, indicating declining species richness and evenness at higher elevations under cooler temperatures and greater environmental stress. Ten endemic woody species were documented, with endemic richness positively associated with altitude, reflecting the role of habitat isolation and environmental filtering. These findings provide essential insights for biodiversity conservation, climate adaptation, and ecosystem management in Al-Jabal Al-Akhdar and comparable mountainous ecosystems.

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.

Forest management of durmast oak stands [Quercus petraea (Matt.) Liebl.] is focused on the production of high-quality assortments for the furniture industry. Due to various forest management factors and impacts of climate change, their vitality and quality are often reduced. Sudden illumination of the oak trunk caused by management cuts can lead to epicormic shoot formation. This study compared two localities and nine long-term research plots at the stand age of 62–68 years in Slovakia. While one locality was affected by the massive dieback of oak in the past, the other was not. The epicormic shoot occurrence was monitored separately in the lower and upper parts of the trunk, depending on selected quantitative tree parameters and on the various management methods. The formation of epicormic shoot was influenced especially by DBH, crown width and crown volume. The occurrence of shoots was always markedly higher in the upper part of the trunk compared to the lower one. During a 35-year period, the development of the proportion of epicormic shoots in the lower part of the trunk in the locality with massive dieback of oak confirmed a higher occurrence on control plots compared to the managed plots with thinning interventions. It showed that the occurrence of epicormic shoots in durmast oak stands was influenced not only by different methods of management but also by the dieback effect in the past. Promoting more intensive thinning in early-stage oak stands is advised, as it prompts trees to develop larger crowns with limiting formation of epicormic shoots.

Tree-ring analysis is a valuable tool for understanding long-term climate patterns and their influence on tree growth. This study investigates the climate–growth relationships of Khasi pine (Pinus kesiya Royle ex Gordon) in Doi Khuntan National Park, northern Thailand (at elevations of 850 to 1 035 m a.s.l.), to reconstruct past climate and inform forest management. Using 48 cross-dated increment cores, we developed an 83-year chronology (1936–2018). Standard dendrochronological methods and regression models were applied. The radial growth of P. kesiya was primarily influenced by moisture availability, showing significant positive correlations with March rainfall (r = 0.39, P < 0.01) and April–July relative humidity (r = 0.45, P < 0.01). Growth was negatively correlated with April–July mean temperature (r = –0.47, P < 0.01), indicating that warmer wet seasons induce stress. False-rings served as complementary intra-annual drought proxies, linked to cool-dry transitional periods. Multiple regression models explained 40.6% of radial growth variance and 65.6% of false-ring frequency variance. Reconstructed climate series revealed significant warming trends since the 1930s, most pronounced in April extreme minimum temperature, which increased by +0.98 °C over the study period (Mann-Kendall test, P < 0.01). These findings highlight the vulnerability of montane pine forests to increasing temperatures and atmospheric dryness, providing a multi–proxy baseline for climate change adaptation.

The black locust (Robinia pseudoacacia L.) is the second most planted tree species worldwide, and the most common in Hungary. Phenotypic traits, particularly flowering patterns, are well-established indicators of the species' response to climate change. This study examined four forest subcompartments across three Hungarian regions: Northern-Central, Eastern and Southern-Central. The aim was to identify climatic factors correlating with the onset and duration of the flowering period. Additionally, the relationships between these factors and nectar weight and sugar concentration were defined. Results indicate a strong negative correlation between precipitation levels and flowering time: lower accumulated and average precipitation during the spring months of the preceding year was associated with a delayed flowering period in the following year (r = –0.922, r = –0.918, P = 0.05). However, when examining the 14-day period (r = 0.829) before blooming or examining from 1 January (r = 0.929, r = 0.890), the results indicate that other environmental factors may play a more dominant role. Furthermore, the number of chill and heat days was found to affect the starting date (R² = 0.819, R² = 0.765).

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.

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.

Land abandonment and the emergence of new forest areas create novel dynamics for forest ecosystems and landscapes. Modelling is often used to forecast tree species composition, age group distribution and spatial patterns in the future. The aim of this study was to develop three scenarios for changes in tree species composition, stand age distribution and spatial patterns of new forest areas and permanent forests using Latvia as a case study. We selected 19 study areas of the size 10 km × 10 km to sample the variety of forest cover patterns, tree species, and stand age. Using GIS tools, we developed three scenarios: baseline, commercial and conservation. Results showed that the conservation scenario resulted in the most even-aged group distribution. Scenarios predicted the increase of Picea abies area (reaching 29.3% in permanent forests and even 45.7% in new forests) and the reduction of Pinus sylvestris in most cases. Changes in the median patch area were the best indicator for evaluation of different scenarios with the largest patches of new forest areas for the conservation scenario (1.92 ± 1.23 ha). The existing structural and compositional integrity of sampled forest landscapes was best retained under the baseline and conservation scenarios, while the commercial scenario indicated more fragmented forest landscapes in the future.

The Colchis forests contribute to the biodiversity hotspot in the Caucasus eco-region. We investigated the plant diversity of these forests in the central part of Adjara (W Georgia). The aims of our study were (i) to differentiate the forest vegetation diversity in the mountain belt forests by means of phytosociology, (ii) to associate endemic taxa with the revealed forest types, and (iii) to assess degradation of the forest vegetation diversity by means of environmental abiotic and biotic factors. We sampled the forest vegetation on 135 plots with the size of 10 × 10 m2 and 237 plant taxa were recorded. Principal Component Analysis (PCA) was used to reduce environmental variables to a few orthogonal composed variables. The derived factors (PC1, PC2) were used in ordination analysis to group the plot measured forest vegetation diversity. One-way ANOVA was used for the comparison of means between the separated clusters in PCA. Two-Way Indicator Species Analysis (TWINSPAN) and Indicator Species Analysis (ISA) were applied for the association of the plant taxa with the vegetation cluster groups separated by PCA. Our analysis revealed two general ecologically distinct forest types which were characterized as dry and humid forests. Endemic species had the main occurrence in dry forests of the studied territory which are heavily impacted by the local land use. The results indicated that the vegetation diversity of dry forests is under higher threat of degradation than that of humid ones because these forests are not protected and are subjected to non-sustainable forest exploitation. Additionally, many rural and invasive plant species change the native plant assemblages. Based on our findings, we recommend to the organization which manages the local forests to find a balance between the use of forest resources and protection of the unique floristic diversity of local forests in order to avoid their degradation.

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.

The European Union (EU) provides both financial and expert support for sustainable forest management initiatives and also boosts compliance with such initiatives in Africa. Thus, there is a need to monitor the progress of implementing such initiatives. The objective of this paper is to describe the role of timber harvesting entities in environmental impact discussions, and to also identify the role of EU institutions in promoting forest sustainability in Sierra Leone. Data were collected in a controlled survey from four communities, using a questionnaire formulated according to guidelines recommended by Babbie and Mouton (2010). The reliability test shows a 0.68 internal consistency among the latent variables (Cronbach alpha test). The selected four communities were Bambawo, Dia, Basara, and Menima, with a population of 6 000, 5 400, 7 500, and 5 600 inhabitants, respectively (Stats SL 2021). A Confirmatory Factor Assessment (CFA) was used for a descriptive statistical analysis of the data. The results showed that the environmental impact has an eigenvalue of 1.08, where only variables with a factor loading exceeding 0.5 were used. The paper concludes with discussions and relevant recommendations on mitigating the impacts of timber harvesting on the environment within the study area.

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.

The response of carabid beetles to extensive livestock farming and vegetation structure in two traditionally managed 'dehesa' ecosystems was investigated. From March 2011 to January 2012, sampling was done, using pitfall trapping, on two forestry farms located in the Sierra de Hornachuelos Natural Park (Córdoba, Spain), both with hunting use, but one of them also with a heavy livestock load. On each forestry farm, two sampling plots were selected according to the vegetation structure. Faunal differences were proved through the ecological indices, and the faunal uniqueness was checked by the Coldwell and Coddington Complementarity Analysis. To identify the most influential factor on the carabid biodiversity, a Generalised Linear Mixed Model (GLMM) was performed. Results show that abundance and richness are higher in the plots with open vegetation, similarly like the number of recorded tribes. Nevertheless, the ecological indices do not reflect any significant differences. The complementarity between different vegetation structures exceeds that of the exploitation types. In fact, the GLMM analysis indicated that the livestock itself does not have a significant effect on the fauna. In addition, all exclusive, rare or endemic species came from the closed vegetation plots, suggesting that these areas may act as a reservoir of unique species in terms of biodiversity.

Natural regeneration is a crucial factor in improving the economy of forest estates. The presented study analysed the economic parameters of three different approaches to forest regeneration: (i) artificial regeneration with Norway spruce, (ii) a 25% admixture of soil-improving and stabilising species (SSTS), and (iii) natural regeneration. The expenses for these specific operations related to individual regeneration methods were derived. These variants were investigated before the bark beetle calamity (2014) and after the outbreak (2023) for management sets (MS) 531, 551, 571, and 591, i.e. for acidic, nutrient-rich, gleyed, and waterlogged sites of higher elevations. In all cases, natural regeneration decreased expenses by approximately 2 000 EUR·ha^–1 (50 000 CZK·ha^–1) to 6 000 EUR·ha^–1 (150 000 CZK·ha^–1). The 25% admixture of SSTS increased the expenses. The proportion of natural regeneration subsequently decreased due to the bark beetle calamity from roughly 40% to 10% in recent years, which is comparable with the Czech Republic as a whole.