The paper presents the results of studying the structure patterns of birch forest stands growing in the coastal belt of the White Sea within the breast height. The research aims to assess the structure of birch stands (by trunk diameter and trunk shape variability) that develop under harsh climatic conditions: low temperatures and strong wind loads. Trunk curvature is observed primarily in the butt end and requires adjustments when determining the location of the breast height. Eleven sample plots were laid out following standard procedures and considering the specific features of the tree stands in various forest types. The sites are located in protective forests, and no silvicultural activities have been carried out there. The diameters and heights of all birch trees and trees of other species have been measured. Diameters were measured in two mutually perpendicular directions (N–S and W–E) at a height (or length, in cases where the lower part of the trunk is severely curved) of 1.3 m from the root collar. A trunk curvature coefficient was determined for each birch tree with a visually discernible trunk curvature. The sample populations have been tested for normality. Sample skewness and the reliability level have been taken into account. The study found that the studied forest ecosystems are stable, long-term developing systems that serve as a protective barrier for the mainland’s forests against northern winds. We observed ongoing differentiation of birch tree trunks and stand formation as a result of intraspecific and interspecific competition. We obtained tree diameter distribution series and models of these distributions. A left-skewed tree diameter distribution relative to the normal distribution was observed. Studying the features of the structuring and growth of birch stands along the White Sea coastline will enable the development of recommendations for improving sustainable forest management and refining inventory standards. Funding: The article presents the results of research and development work carried out within the framework of a government-funded project assigned to the Federal State Budgetary Institution “Northern Research Institute of Forestry” for applied scientific research in the field of the Federal Forestry Agency (project registration No. 123022800118–4). For citation: Koptev S.V., Tretyakov S.V., Bogdanov A.P., Golyshev V.A. Birch Tree Stand Structure by Diameter in the Coastal Belt of the White Sea. Lesnoy Zhurnal = Russian Forestry Journal, 2026, no. 5, pp. 195–204. (In Russ.). https://doi.org/10.37482/0536-1036-2026-5-195-204
Forest management activities are essential for the formation of Siberian stone pine forests in burned-out and clear-cut areas. The research aimed at studying the environmental conditions and early development of Siberian stone pine (Pinus sibirica Du Tour) undergrowth of the first generations of subsequent regeneration in young stands forming in burned-out and clear-cut areas. The works were carried out in the middle taiga subzone on the border of the Middle and Northern Urals, in the low-mountain part of its eastern macroslope. In the reforestation composition birch (up to 25,000 trees/ha) and other anemochorous woody plants were found to predominate in the most part of the burned-out and clear-cut areas. As a result, light-coniferous small-leaved young stands develop there. The number of Siberian stone pine undergrowth groups does not exceed 1,500 per 1 hectare. Compared to other forest-forming arboreal plants, Siberian stone pine undergrowth only predominates in the burned-out areas within the upland group of forest types. The formation of Siberian stone pine forests here occurs naturally at the early growth stage. The average projective cover of herbaceous vegetation here is 28–34 %, and the canopy density is no more than 10 %; the height and current vertical increment of Siberian stone pine undergrowth is nearly 1.5–2.0 times exceed these parameters in young stands in burned-out and clear-cut areas in the green-moss group of forest types. The projective cover of tall grasses is 63–79 % and the canopy density of small-leaved trees is 54–58 % in the green-moss forest group. The results of the study suggest a new forest management approach for converting small-leaved young stands into Siberian stone pine stands by the time the trees reach 20 years, through the regular intensive cutting of Siberian stone pine undergrowth. Funding: The work is carried out within the state assignment of the Botanical Garden of the Ural Branch of the Russian Academy of Sciences (state registration No. 123112700125-1). For citation: Tantsyrev N.V., Terekhov G.G., Terinov N.N. Siberian Stone Pine Undergrowth in Natural Coniferous Small-Leaved Young Forests of the Urals. Lesnoy Zhurnal = Russian Forestry Journal, 2026, no. 5, pp. 31–43. (In Russ.).
The research was carried out on the largest yaylaks of Crimea. The work aimed at defining the seed regeneration patterns of Pinus sylvestris on the Crimean yaylaks. Areas containing P. sylvestris undergrowth were found using transect surveys. The undergrowth distribution density was determined in 10×10 m sample plots laid out with 20 m intervals from the edge of artificial P. sylvestris stands. We studied the biometric and age-specific parameters, and assessed the quality of self-seeding using the forestry and field geobotany methods. As a result, significant differences were found in the occurrence and biomorphological parameters of undergrowth on the Crimean yaylaks. The highest variation coefficient is observed for the frequency of undergrowth occurrence – 52.3 %, which indicates significant unevenness in its spatial distribution. On the Babugan yaylak, the age structure is represented by two groups: 6- and 7-year-old undergrowth. Three age groups have been found on the Nikitskaya yaylak; younger, 5-year-old plants predominate in the age structure. It has been found that the probability of P. sylvestris self-seeding in the conditions of the Nikitskaya yaylak is 30 % higher compared to the Babugan yaylak. The temperature regime is the most important factor controlling the growth and development of seedlings in the ecotopes of the Crimean yaylaks. An increased density of self-seeding was observed at a distance of 100 m southeast from the edge of artificially planted P. sylvestris on the Nikitskaya yaylak. The maximum value of this parameter on the Babugan yaylak was observed at a distance of 300 m northeast from the stand edge. Natural regeneration of P. sylvestris on the Nikitskaya and Babugan yaylaks is assessed in certain areas as promising based on age characteristics and distribution density. For citation: Koba V.P., Krestianishin I.A. Distribution Density and Biomorphological Features of Pinus sylvestris L. Undergrowth on the Crimean Yaylaks. Lesnoy Zhurnal = Russian Forestry Journal, 2026, no. 5, pp. 60–73. (In Russ.). https://doi.org/10.37482/0536-1036-2026-5-60-73
This research focuses on developing the key parameters for aspen bark wood waste (generated during drum debarking) conversion into fuel briquettes, which are in demand on the market. The research object was the fuel briquettes production and the raw materials balance in the production of fuel briquettes from aspen round timber bark waste. The research subject was briquettes made of aspen bark waste. The experimental studies were carried out in actual production conditions with industrial equipment. The criteria for selecting process parameters were the requirements of regulatory documents governing the wood biofuel properties. The manufactured briquettes were tested for their properties by the accredited laboratory equipment. Standard briquettes made of grinding dust produced during the birch plywood processing, as well as briquettes consisting of 50 % aspen bark waste, were manufactured as control products. The requirements for the particle size distribution of wood particles have been determined (based on the literature references) depending on the briquetting technology. The data obtained from the literature analysis have been confirmed by empirical testing. Experiments have shown the effect of the specific molding pressure of aspen bark waste on the resulting briquettes density. The minimum molding pressure required to produce briquettes with the density specified in the regulatory document has been determined. A balance of raw materials has been drawn up to produce fuel briquettes from round timber bark waste, and the main performance indicators to produce briquettes from aspen bark waste have been determined. The higher and lower heating values, as well as the ash content and other properties of briquettes made of aspen bark waste, have been determined. As a result, we have developed a new type of fuel briquette made of aspen bark waste, and determined its properties. The scope of scientific research findings is the effective utilization of bark waste to produce marketable biofuel. For citation: Bastrikov D.V., Polyanskaya O.A., Tambi A.A. Industrial Production Procedure of Briquettes from Aspen Bark Waste. Lesnoy Zhurnal = Russian Forestry Journal, 2026, no. 5, pp. 141–151. (In Russ.). https://doi.org/10.37482/0536-1036-2026-5-141-151
The influence of airborne industrial pollutants on the woody plants state in the taiga zone is a poorly studied and urgent issue. The research aimed at analysis of mycorrhization characteristics and fine roots biomass of Siberian spruce (Picea obovata Ledeb.) in bilberry spruce characteristics located within the zone of airborne industrial emissions impact of the Syktyvkar Timber Industry Complex enterprises. The studies were carried out in old-growth bilberry spruce forests at a distance of 3.5, 9.5, 24 and 50 km from the emission source in the direction of prevailing winds. The biomass and structure of Siberian spruce fine roots were studied in the zone of the Syktyvkar Timber Industry Complex enterprises influence. We have examined the morpho-anatomical structure of Siberian spruce fine mycorrhizal roots by light microscopy. There was an increase in the Siberian spruce roots biomass in the forest litter of coniferous phytocoenosis located in the enterprise’s impact zone. The results obtained for spruce root biomass across all four study plots are consistent with root mass values observed in coniferous phytocoenoses of the middle taiga in the Komi Republic. In the spruce forest within the enterprise’s impact zone, an increase was observed in mycorrhizal density, mycorrhization intensity, ectomycorrhizal diameter and thickness, and the volumetric fraction of the fungal mantle. The spruce forest compared to other communities has the greatest diversity of fungal mantles with a predominance of more complex and physiologically more active mantles of pseudoparenchymatic and double folding. At the same time, in the spruce stand within the impact zone, a trend is observed toward an increased occurrence of tannin cells in the root cortex and a higher proportion of root tips that have lost turgor, suggesting a decline in the physiological activity of absorbing roots. All the listed characteristics indicate an adaptive response of the spruce to the conditions prevailing in the community. All other spruce forests (except the impact zone forest) were defined by a clear predominance of plectenchymatous mantles, a pattern typical of natural coniferous stands in the middle taiga of the Komi Republic. Funding: The research was carried out within the framework of the research and development topic “The Habitat-Forming Role and Productivity of Forest and Swamp Ecosystems of the European North-East of Russia” (Registration No. 125020501547-8) and the contract-based research topic “Assessment of the Long-Term Impact of JSC Mondi SLPK on Biological Diversity in the Production Area” (Contract No. 45-2018 dated April 24, 2018). Acknowledgments: The authors are deeply grateful to the staff of the Department of the Forest Biology Problems of the North, Institute of Biology, Komi Science Center, Ural Branch of the Russian Academy of Sciences E.A. Robakidze, T.A. Pristova, and M.A. Kuznetsov for their assistance in collecting field material and analyzing samples, as well as to the Doctor of Biological Sciences S.V. Zagirova for the valuable comments on the manuscript. For citation: Sizonenko T.A., Manov A.V., Naimushina S.I. Mycorrhization Characteristics and Fine Roots Biomass of Siberian spruce in Aerotechnogenic Pollution of a Timber Industry Complex. Lesnoy Zhurnal = Russian Forestry Journal, 2026, no. 5, pp. 89–106. (In Russ.). https://doi.org/10.37482/0536-1036-2026-5-89-106
