The sizes of planting material of Pinus sibirica Du Tour of four-year biological age, grown with an open root system without transplantation (seedlings) and with transplantation (saplings), as well as with a closed root system in substrates of different compositions, were analyzed. The planting material differs in height and stem diameter depending on the growing method and type of substrate by the end of the fourth growing season. 

The morphology of tree crowns determines the scale and effectiveness of physiological processes, in particular, of photosynthesis, respiration and transpiration, which determine the growth and development of a tree, as well as the quality of wood. Therefore, researchers are focusing on developing models of such morphological characteristics as crown length, relative crown length, and height to crown base. The morphological characteristics of the crown serve as predictive variables in models of crown diameter, vertical profile, tree biomass, and crown fires. The purpose of this study is to build generic models for estimating crown length, relative crown length (crown ratio) and height to crown base based on easily measurable dendrometric characteristics of the tree based on the materials of the author's database for two–needled pines (subgenus Pinus L.) of Eurasia. To achieve this goal, 2,700 model trees with measured taxation indicators were selected from the author's database. Since the study has a continental level, the analysis was performed at the level of a subgenus of two–needled pines as a set of vicarious species, bearing in mind that no species grows throughout Eurasia. As a result, generic multiple models were built to evaluate the morphological parameters of the crown – crown length, crown ratio and height to crown base – by stem diameter at breast height, height and age of the tree, explaining from 52 to 88 % of the variability of a particular morphological index of the crown, and their regression coefficients for independent variables are significant at the probability level p < 0.001 and higher. The proposed multiple models for estimating the morphological parameters of the crown based on the known dendrometric characteristics of the tree can be used in dynamic models of tree and stand growth, in the development of biomass models of trees and stands, as well as in the modeling of crown fires. 

The size of cones in different populations of coniferous species differs in their indicators depending on the place of growth, heredity and other factors. The aim of the research was to analyze the variability of 8-year-old Siberian pine seedlings grown from selected cones collected in the Choysky forestry of the Altai Republic. The seeds were sown in the introduction department of the arboretum of the Karaulny Forestry of the Educational and Experimental Forestry of Reshetnev University (suburban zone of Krasnoyarsk). The variability of seed progeny was assessed by height, shoot growth, trunk diameter, and needle length. The level of variation of indicators was established according to the scale of S. A. Mamaev. Studies have shown that cones collected from different trees differed in shape, length, diameter, and number of seeds. The length of the cones varied from 7.5 to 11.5 cm with an average value of 9.1 cm; diameter varied from 5.5 to 6.3 cm with an average value of 5.7 cm. The cones were cylindrical and rounded. The number of seed scales varied from 45 to 89 pcs., the number of seeds varied from 85 to 169 pcs. The largest number of seeds was noted in cone No 29 of cylindrical shape. A close correlation (r = 0.995) was established between the number of seeds (y) and scales (x). The highest height is distinguished by seedlings from cone No 9, which has an excess in length. The level of variation in the height of seedlings in the compared families is from low to high, the interfamilial level of variation (11.3 %) is less than the intrafamilial level. The correlation coefficient between the length of the cones and the growth of seedlings is 0.829. The average length of the needles varied from 8.0 to 9.8 cm, that is, the difference between the extreme options is 22.5 %. Specimens distinguished by intensive growth, a large number of buds and long needles have been identified. 

The half-siblings of Siberian cedar pine (Pinus sibirica Du Tour) are grow on the "Ermaki" plantation in the Sayansky district forestry of the Ermakovskoye forestry in Krasnoyarsk region. These are the seed progeny of plus trees certified for seed productivity in 1977 in the Kolyvan forestry district of Novosibirsk region: 89/53, 90/54, 99/63, 103/67, 109/73, and 110/74. The variability of indicators of half-siblings was compared between and within families. The half-siblings were selected for the highest formation of macrostrobili and cones: in family 89/53, halfsiblings No. 10-18 and No. 10-11 (the excess over the average was 120.3 % and 78.0 %), in family 90/54 – No. 10-35 (129.2 %), 99/63 – No. 10-19 (75.1 %), 106/63 – No. 10-32 and No. 10-27 (60.0 % and 50.0 %), 109/73 – No. 10-28 (115.7 %), 110/74 – No. 10-16, No. 10-23 and No. 10-9 (114.2 %, 111.2 % and 80.1 %). The half-siblings with the highest number of microstrobiles were selected: No. 2-6 in family 89/53 (the excess was 126.9%), No. 2-7 in family 90/54 (54.0 %), No. 2-23 in family 99/63 (137.3%), No. 2-30 in family 103/67 (264.3 %), No. 2-24 in family 109/73 (132.8 %), No. 10-23 in family 110/74 (71.8 %). These half-siblings are recommended for propagation to grow planting material with increased seed productivity. 

Climate change resulting from increased carbon dioxide emissions into the atmosphere is an important global issue. Forests and the forestry sector can play a significant role in achieving this goal, as they are crucial carbon sinks. Forest management practices can support or enhance carbon absorption and storage in forests. Significant activities in forest management include care measures such as thinning and cleaning cuts, selective logging, and sanitary cuts. The article examines data on stand volumes, inventory data, and information on care cuts according to the records of two forestry units in the Republic of Karelia: Pedaselga and Pyazhieva-Selga. The accounting was conducted over 20 years: from 1996 to 2016. The data was structured and digitized. An analysis was conducted, revealing dependencies of the increase in stand growth on parameters such as the time interval between care cuts, the volume of felled timber, changes in relative density, and species composition.

The paper formulates recommendations for care cuts in young forests of the Republic of Karelia in accordance with the findings based on the identified patterns. The recommendations are aimed at increasing timber growth and reducing carbon emissions into the environment. 

The role of green spaces, and individual species in particular, in improving the environmental comfort of the urban environment is generally recognized. Due to the significant heterogeneity of anthropogenic impact and its specific characteristics within the urban environment, the introduction of specific types of woody vegetation into landscaping practices should be preceded by a comprehensive assessment of their adaptability to local conditions and types of plantings. Recommendations for the large-scale use of dendroflora are possible only after a detailed study of plant resistance to the existing technogenic load in specific urban biotopes. Taking into account the specifics of pollution and the category of plantings is a prerequisite for the successful introduction and sustainable development of woody plants in an urbanized environment. A method is proposed for determining the assessment of the quality of plant growing conditions based on the asymmetry of the area of halves of leaf blades of woody plants. The object of the study was middle-aged silver birch plants, located in the same conditions in terms of illumination and humidity, but with different intensities of anthropogenic load. To assess the sustainability of Betula pendula development, two criteria were used: the asymmetry coefficient determined by five leaf parameters, and the asymmetry index calculated based on the area of leaf halves using the methods of V. M. Zakharov [Zakharov, 1987] and a modified author's method.

Analysis of the correlation between the area of leaf blades and the degree of environmental pollution demonstrated a general tendency towards a decrease in the stability of development. Statistically significant inverse correlations were found: an increase in technogenic load leads to a decrease in the area of Betula pendula leaf blades and an increase in their asymmetry.

The results obtained indicate that the developed and tested bioindication method based on the analysis of leaf blade asymmetry through the ratio of the areas of their halves correctly reflects the changes occurring in the environment. This method can be recommended for the prompt assessment of the quality of the urban environment as part of environmental monitoring. 

The article provides a brief description of the tasks solved to date to coordinate the spectral characteristics of wood species with the optical properties of an IR radiation generator, as well as a theoretical description of the process of infrared drying of lumber in a vacuum chamber, on the basis of which calculations, design and manufacture of an infrared vacuum drying unit were performed. The technology of the lumber drying process in the developed installation is described. It is noted that the drying process is multiphysical (heat exchange by radiation, condensation of moisture, degree of dilution, form factor effect, etc.), therefore, in order to establish relationships at the developed installation, it is planned to conduct a multifactorial experiment to work out the modes for one type of wood and then adjust them to other species. To reduce the number of natural experiments, there are currently mathematical modeling software products that allow conducting research on multiphysical processes in complex structures, including the developed installation. The purpose of the study is to verify the adequacy of the mathematical model of the lumber drying process in an infrared vacuum drying unit. A natural experiment was conducted on drying wood planks, for which temperature data was obtained for different points inside and outside the vacuum chamber during the entire drying process. Further, a metric model was reproduced in the mathematical modeling software product, considering the details of the installation design, technological equipment, and features of the form factor placement of lumber. And for this metric model, calculations of the temperature field in the lumber drying zone were performed. When comparing the experimental data obtained and using the software product, the identity of the temperature parameters of the film electric heaters is traced, and the temperature difference between the lower and upper rows of stacked boards is proved. The conclusion is that the mathematical model of temperature distribution in an infrared vacuum dryer is correct. 

At present, a promising direction is the cultivation of planting material with a closed root system (PMCRS) and its use to create forest crops. Modern technologies for growing seedlings with a closed root system allow saving coniferous seeds by 10–20 times compared to sowing in open ground. When using this technology for growing planting material, the main current trends are: precise sowing of seeds, efficient use of film greenhouses, technologies and equipment for sowing seeds and caring for seedlings, rational use of seeds, mechanization of the process of planting forest crops and further care for them. The main device of this complex is the equipment for sowing seeds. The article presents an analytical review of existing analogues of seeders for sowing seeds in cassettes. The principle of operation of the seeder is to use a vacuum seed capture. For reliable capture of one seed at the capture point in the hollow shaft, the holes are made at the seed capture points. They are able to capture only one seed by vacuum inside the shaft. That reduces the likelihood of accidental capture of two or more seeds and ensure the sowing of a given number of seeds in each well. When seed is dropped from the gripper points of the shaft into the Seed Collector with Distribution Tubes, the vacuum holding the seed is replaced by positive pressure, which allows the seed to be released and the gripper holes in the shaft to be blown out. The article presents a 3D Model of the complete seeder and 3D Models of individual devices, an experimental sample of the precision seeding device, a control unit for the precision seeding device. Based on the results of the work carried out, the design and optimal parameters of the device for precise seeding of seeds in cassettes for growing seedlings with CRS were determined, compressed air consumption was minimized, and the operating speed was increased (one sowing cycle in 3 seconds) which makes it possible to achieve a line capacity of up to 1200 cassettes per hour (100 thousand seeds per hour), which exceeds foreign and domestic analogues. 

It is known that the process of grinding fibrous polymers from coniferous and deciduous wood is very important in the technology of producing paper and cardboard. Knife and non-knife grinding methods are used for this purpose. From the practice of this process, knife grinding is used in the technology of obtaining the finished product in pulp and paper production in the vast majority of cases.

When using knife grinding, the main effect on the fiber is considered to be mechanical. At the same time, with an increase in the speed of rotation of the rotor of knife mills, hydrodynamic effects during the flow of fibrous suspensions in the working areas of knife machines begin to play a serious role in the process of grinding fibrous semi-finished products. It is still not clear at what speeds of movement of fibrous suspensions it is necessary to take into account the effect of hydrodynamic forces on the grinding process.

To solve this problem, the analysis of the contact of the suspension jet with an obstacle during grinding of plant polymers was carried out. The phenomenon of suspension contact during grinding is observed in both knife-free and knife installations. In knife machines, the slurry flows during the process come into contact with the inner surfaces of the rotor and stator, and especially they hit the surfaces of the working bodies of the mill.

In this regard, the calculation of the instantaneous impact of a suspension jet with an obstacle was carried out. 

Humanity has always faced the challenge of finding cheap energy sources that do not require excessive costs. Traditional forms of biofuels, such as firewood, plant residues, and dried manure, account for the majority (54– 60 %) and are used for home heating and cooking. Biofuels are classified by their physical state and the generation of their raw materials. Hydrolysis lignin, like any organic matter containing significant oxygen, is prone to fermentation regardless of storage conditions. Hydrolysis lignin is characterized by a large pore volume, approaching the porosity of charcoal, high reactivity compared to traditional carbonaceous reducing agents, and twice the solid carbon content compared to wood, reaching 30 %, which is almost half the carbon content of charcoal. The aim of the scientific research was the possibility of processing hydrolysis lignin to produce biofuel. Hydrolysis lignin (HL) samples were taken from an industrial sludge dump on the territory of the former Kansky BioChemFactory LLC. Sampling was carried out in dry weather in compliance with the necessary requirements. The studies allow us to conclude that technical hydrolysis lignin is a multicomponent compound, including technical lignin (60–70 %) and related substances: extractives (7–22 %), represented (organic part) by monosaccharides and their decomposition products, terpene hydrocarbons and their oxygen-containing derivatives, aromatic compounds, aliphatic hydrocarbons, highmolecular-weight acids; residual polysaccharides (2–8 %). A method for processing hydrolysis lignin from the dumps of the Kansky Biochemical Plant is proposed, which makes it possible to reduce the anthropogenic load on the atmospheric air and soil by eliminating the storage facility, while obtaining alternative biofuel. 

Humanity has always faced the challenge of finding cheap energy sources that do not require excessive costs. Traditional forms of biofuels, such as firewood, plant residues, and dried manure, account for the majority (54– 60 %) and are used for home heating and cooking. Biofuels are classified by their physical state and the generation of their raw materials. Hydrolysis lignin, like any organic matter containing significant oxygen, is prone to fermentation regardless of storage conditions. Hydrolysis lignin is characterized by a large pore volume, approaching the porosity of charcoal, high reactivity compared to traditional carbonaceous reducing agents, and twice the solid carbon content compared to wood, reaching 30 %, which is almost half the carbon content of charcoal. The aim of the scientific research was the possibility of processing hydrolysis lignin to produce biofuel. Hydrolysis lignin (HL) samples were taken from an industrial sludge dump on the territory of the former Kansky BioChemFactory LLC. Sampling was carried out in dry weather in compliance with the necessary requirements. The studies allow us to conclude that technical hydrolysis lignin is a multicomponent compound, including technical lignin (60–70 %) and related substances: extractives (7–22 %), represented (organic part) by monosaccharides and their decomposition products, terpene hydrocarbons and their oxygen-containing derivatives, aromatic compounds, aliphatic hydrocarbons, highmolecular-weight acids; residual polysaccharides (2–8 %). A method for processing hydrolysis lignin from the dumps of the Kansky Biochemical Plant is proposed, which makes it possible to reduce the anthropogenic load on the atmospheric air and soil by eliminating the storage facility, while obtaining alternative biofuel. 

The results of the study of a new contact tray for a diabatic distillation column that is recommended for use in the wood chemical industry are presented. The presented tray has low metal consumption, hydraulic resistance and holding capacity combined with high separating one. The device includes a packing to provide a cross current flow of vapors located in coaxially mounted perforated cylinders, above which a heat exchanger device and profiled plates are placed to perform a partial condensation and evaporation. The efficiency of the tray is investigated with a respect to the concentration of volatile components in the mixture and its hydraulic resistance. The intensity of an ethanolwater vapor mixture condensation on the surface of a heat exchanger coil and on the surface of horizontally mounted plates of a tray has been studied. The equations for calculating the values of the heat transfer coefficients are established. The evaporation of volatile components from the surface of the plates is investigated, and dependence is obtained, that makes it possible to estimate the consumption of vapors from the surface of the plate and the specific heat load of condensed vapors under the plate. The concentrations of ethanol in rising vapors and condensate along the height of the tray is shown. A reduction of a metal consumption, holding capacity, flow resistance and efficiency has been achieved in comparison with the adiabatic countercurrent column. 

The raw material base for the pulp and paper industry has a very wide range. However, despite this, the main raw materials are still plant fibers (coniferous and deciduous wood, annual plants), which negatively affects the environment as a whole. Due to the wide range of applications of pulp and paper products, manufacturers of finished products are increasingly using fiber compositions of various origins, replacing from 1 to 90 % of plant fibers. This reduces the consumption of plant-based fibers, which in turn has a beneficial effect on the environmental situation.

Currently, there is increasing interest in fibers of bacterial origin, the so-called bacterial cellulose (BC), which, in combination with fibers of plant origin, makes it possible to obtain a finished product with different characteristics and different purposes.

The study presents the results of obtaining composite raw materials from softwood fibers and BC for pulp and paper production; the results of physico-mechanical tests of finished products are presented.