The growing conditions (under the forest canopy and in the openplace) affect the growth rate of Siberian cedar pine plantations. Faster growth is observed in Siberian cedar pine plantations grown in conditions of greater illumination. The trees grown in the open area are 2,7–3,3 times larger in trunk diameter than trees grown in shading under the forest canopy, depending on their geographical origin.

The geographical origin of planting material affects the growth rate of cedar plantations, regardless of their growing conditions. The best growth in the conditions of the arboretum located in the suburban area of Krasnoyarsk, both in the open and under the forest canopy, was distinguished by the offspring of the Siberian cedar pine of Tuva origin. Slow growth was noted for the offspring of the Buryat climatype.

Krasnoyarsk Krai has significant reserves of coniferous boreal forests and a developed river network formed by the tributaries of the Yenisei, Angara, Chulym, Kan, Pyasina, etc. The rivers of Krasnoyarsk Krai are still used for water transport and timber rafting. The length of rafting routes along the Angara and Yenisei rivers is about 3000 km. The main characteristics of a river are length, width, depth, flow, catchment area. Depending on the size parameters, rivers are classified into small, medium and large.

Small and medium rivers have been widely used and are partially used today for timber rafting purposes.

The following types of timber rafting are distinguished: loose floating, bag boom floating, in raft sections and rafts. With loose floating, the timber is transported downstream in the form of unrelated assortments of roundwood and microbundles with a sufficient buoyancy margin. Loose floating is used on non-navigable rivers, where, due to the conditions of shallow depths or the short duration of the rafting period, the effective use of other types of water transport is not ensured. With the adoption of the “Water Code of the Russian Federation” No. 167-FZ dated 11/16/1995, and then No. 74-FZ dated 06/03/2006, a decision to ban loose floating was approved [3; 9; 22; 24].

On 13 February 2020, the Russian Government issued Decree No. 7 on invalidation of regulations that prohibited loose floating on rivers and reservoirs [21].

In this regard, it is necessary to assess the transport role of small and medium-sized rivers, the reasons for the loss of wood in the process of loose floating, the possible negative impact of loose floating on water quality and the environment during its renewal.

The presented work shows the role and importance of small and medium-sized rivers in the transport supply of forest resources to timber industry and wood processing enterprises.

The article includes an introduction with the definition of landscape design. Arguments are given about the increasing role and importance of landscape design in the modern improvement of urban areas and homesteads. The article describes the social significance of landscape design in order to create a system of green spaces of a modern city and homesteads.

The main part of the article includes a description of the factors influencing the formation and development of urban green spaces (climate, relief, existing vegetation, soil, the presence of reservoirs, geological and hydrological conditions). The main guiding ideas in landscape design are listed: the idea of stylistic unity; the idea of continuity – taking into account cultural traditions; the idea of efficiency; the idea of complexity, the idea of combining utility and beauty. It is mentioned in the article how important is the compositional consistency of small architectural and landscape forms with the surrounding buildings, landscape design, their scale to a person and the surrounding space.

The article provides a detailed description of the selected landscape objects that belong to the category of public facilities, are visited and are located in the central district of Krasnoyarsk. A result of the work carried out on the study of the territories of landscape objects in Krasnoyarsk, the principles of modern landscape design are highlighted.

The assessment was given regarding the vital state of the pine forests in the Zatyumensky Ecopark based on indicators of the sanitary and vital status, relative height and a comprehensive assessment indicator. According to majority of indicators, the vital state of pine forests in the zone of active visits is assessed as severely weakened, in the zone of moderate and weak visits – as weakened. Common pattern of an increase in the number of severely weakened and dying trees and a decrease in the number of healthy trees with an increase in recreational impact has been observed. In particular, there is a decrease of healthy trees by 7–9 times in the zone of active visits with an increase of weakened and dying trees by 2.5–5 times compared to the zones of moderate and weak visits. The analysis of tree trunk damage types showed that the most common types are tree scorch marks, resin flow and mechanical damage. Common pattern of an increase in the number of tree damages with an increase in recreational impact has been observed. It was found that the in the zones of active visits the number of trees scorch marks on tree trunks, wood-destroying fungi and with mechanical damage is 1.5–5 times more compared to the zones of moderate and weak visits. In order to prevent degradation of pine plantations of the Zatyumensky Ecopark and increase their sustainability, a number of forestry measures are proposed, in particular, temporary fencing of forest areas in critical condition for the period of their restoration; landscape felling to rejuvenate stands and create recreationally attractive sustainable landscapes of semiopen type, etc.

Due to climate change and the potential possibility of its stabilization with the help of managed forests and assessment of their carbon depositing capacity, the possibility of operational assessment of biomass and organic carbon of forest cover becomes particularly relevant. In recent years, remote sensing technologies of forests based on unmanned aerial vehicles (drones) have made it possible to obtain the values of the parameters of tree crowns from as close distance as possible. That provides not only high accuracy and speed of measurements, but also the ability to distinguish trees by species composition. In this study, an attempt is made to develop allometric models designed to estimate the biomass of trees of forest-forming genera in Russia by crown diameter. To achieve the research goal, an author's database of 15200 definitions of tree biomass was used. A number of 1665 model trees of five coniferous and 780 model trees of six deciduous species were selected from it. Since the actual values of the biomass of trees are presented in the database by several vicarious species within the genus, the analysis of the dependence of the biomass of a tree on its crown diameter is performed at the level of genera and subgenera. A package of allometric models of the biomass of trees of full component composition for each genera and subgenera is calculated, all regression coefficients of which are significant at the level of p < 0,001. The proposed allometric models can be used to estimate the biomass and organic carbon of trees and stands of forest-forming genera in Russia based on digital photogrammetry of visual data obtained using drones.

The results of soil studies on two fresh cuttings formed as a result of continuous cutting of mixed pine stands in the winter and summer periods of the year are presented. Negative changes in the soil cover of both cuttings were revealed, the degree of which is determined by the intensity of the impact of machines used on various technological elements of cutting areas, as well as the season of logging. These changes are manifested in the destruction of the litter on the loading areas and skidding portages of both cuttings, as well as the deterioration of the structure of the upper mineral layers, an increase in their density and a decrease in overall porosity with a simultaneous increase in small capillary pores, which greatly reduces the water permeability of the soil. At the same time, these changes are less pronounced in the apiaries of both cuttings.

In addition, more negative quantitative changes in the physical properties of the soil are observed during summer logging, which in the future will appropriately affect the course of natural regeneration of the resulting cuttings. Based on this, in the ecological and economic aspect, it is advisable to carry out the bulk of clear-cuttings in winter.

We analyzed the existing methods of determining the abundance of plant species of the living ground cover in the biocenosis and selected the most effective methods for determining bryophyte abundance. Special attention was paid to the use of modern information technologies for full or partial automation of determining the total and partial projective cover of the living ground cover. In our work, we investigated the possibility of using graphics editors having a graphics processing module with the function of auto-extraction, vectorizer programs, CAD computer-aided design systems, which showed good results for accuracy and efficiency of work. Currently, there is no single high-quality specialized program for complete automation of photo plots processing and determination of projective coverage. It is currently impossible to obtain reliable data without operator's correction when digitizing a photoplot and allocating blocks of areas of individual plants. But, using modern information technologies, it is possible to automate many stages of work, which significantly reduces the time spent on the study of plant abundance. Also, our study showed a higher accuracy of determining the projective coverage of bryophytes, and, in fact, the complete elimination of subjectivity, compared to the glance-based methods. The results of the study showed: in spite of the use of several programs, the speed of processing of registration sites with the use of information technologies was significantly higher than the glance-based methods. This makes it possible to recommend the use of modern information technologies in the analysis of bryophyte abundance.

The article is devoted to the assessment of functional indicators of litter decomposition in forest areas. Forest litter influences processes such as the intake of nutrients, the formation of humus, carbon accumulation, and the frequency of ignition. The annual dynamics of litter is characterized by an increase in its quantity by the end of the dry period and is closely related to the rainy season. The main factors affecting the decomposition of litter in forests are temperature and moisture content, as well as various microorganisms. The decomposition of litter in the forest is an important factor in the transport of CO₂ from the forest into the atmosphere. It is obvious that this dependence of the CO₂ release rate leads to a seasonally dependent estimate of the amount of CO₂ released in forests. At the same time, there are averaged model estimates of the decomposition of litter mass in forests per year. The density of wood negatively affects the rate of CO₂ release during the decomposition of wood pulp. Taking into account the above, the issue of an average estimate of the rate of CO₂ release from litter in forest areas where litter collection and processing measures are not carried out is considered.

Two questions are investigated: (a) the question of the existence of such an optimal functional dependence of the exponential decomposition rate of the litter on its initial mass at which the total remaining mass of the litter reaches a minimum value. The existence of such an optimal velocity is shown, which is directly proportional to the logarithm of the initial mass of the litter. The question of the dependence of the CO₂ release rate during the decomposition of the litter on the initial mass of the litter is also investigated. The analysis showed that there is no such dependence in the above optimal mode.

The article discusses a method for calculating the physical parameters of a thermally stretched unit for surface treatment of wood composite boards in order to achieve the most beneficial economic results and obtain the lowest surface roughness of such boards. The necessary requirements for surface treatment of wood composite boards are given. The kinematics of the drive of a thermo-drawn processing tool is considered in order to achieve optimal characteristics of the surface of a chipboard for lamination and use in the furniture industry. The necessary requirements for processing technology to achieve the optimal values of chipboard roughness are considered.

The article discusses the design of the working body of a forest fire soil thrower, designed to fight forest ground fires by laying a mineralized strip with simultaneous throwing of the edge of the fire with mineralized soil, with the determination of its power indicators depending on the depth of the strip.

For the design of the working body of the forest fire ground thrower, a utility model patent of the Russian Federation No. 117091 was received, the patent holder of which is the Siberian State Technological University.

The utility model relates to devices designed for laying protective mineralized strips, as well as extinguishing ground fires with soil, especially in waterless forests. The utility model allows to increase the width of the mineralized strip due to the implementation of the working body in the form of throwing knives, made in the form of a "rod" spiral section, installed on the carrier disk at an angle α between the rear edge of the knife and the plane of rotation of the milling disk, and rotated relative to the trailing edge in the direction movement through the angle β. In this case, the diameter of the carrier disk is equal to the diameter of the circle described by the ends of the throwing knives, which increases the ground support area enclosed between the front surface of the carrier disk and the throwing knives.

Throwing knives separate the chips from the soil mass, while the cut volume of soil rests against the walls formed by the interface of the frontal plane of the carrier disk and the throwing knives. Throwing occurs as a result of imparting kinetic energy to the cut off part of the soil from throwing knives and the frontal plane of the carrier disk.

The scheme and princip endences of the required power on the depth of the strip being laid are obtained.le of operation of the working body of the forest fire ground thrower are considered, the dep

The introduction and use of ground throwers in the fight against forest fires will minimize damage and harm to the forest ecosystem.

Unstudied are the properties of flooded standing wood, the amount of which in the water area of the Angara-Yenisei HPP cascade, in particular in the conditions of the Bratsk reservoir, is quite large and there is the possibility of its harvesting and processing.

Flooded spruce wood has a gray and gray-brown uneven color and well-defined growth rings with smooth transitions between the zones of early and late wood, which are clearly expressed. A number of changes in the structure of spruce wood have been revealed. It has more saturated dark shade of the cell walls of axial tracheids. The structure of the layers of the cell walls of the tracheal anatomical elements is decompressed, which leads to partial delamination of the walls of early tracheids when transverse sections are obtained. The brown contents of the protoplasts of the parenchymal cells of the rays and the cavities of the ray tracheids are often observed. On the surfaces of cavities, mainly late tracheids, a thin dark-colored layer is revealed, which is the inner layers changed during staining with additional “sedimentary” organic components. In all tracheal and radial anatomical elements of wood, the same type of thin nonseptate hyphae of a wood-destroying fungus are revealed.

The destruction of wood under the influence of a mycological factor may has made a contribution of amorphous deposits in the cavities of wood cells, as well as to a decrease in the mechanical properties of the studied material. In general, during the anatomical analysis of flooded spruce wood, structural changes were identified that could affect the mechanical properties of wood in comparison with non-fusible wood of similar macrostructure. The obtained results of the macroand microstructure of spruce wood samples allow us to conclude that this wood can be further used to obtain new wood composite materials, as well as to improve the modification technology based on the use of flooded wood.

The significant use of imported technological equipment is one of the problems in the development of the reforestation complex in the Russian Federation. To reduce the backlog in this area from the level of development of the leading countries of the world, the Order of the Ministry of Natural Resources and Ecology of the Russian Federation dated December 4, 2020 No. 1014 "On approval of the Rules for reforestation, the composition of the reforestation project, the procedure for developing a reforestation project and making changes to it" was adopted. Special attention in it is paid to accelerating the renewal of the technical base. The development of a complex of equipment for precise seeding of seeds, which includes a device for the formation of holes in cassettes with a substrate, which has an adequate cost and does not require complex maintenance, is an urgent topic of this development and research work. The article presents an overview of the production process of growing seedlings with a closed root system (ZKS) in the Green Building Department of Krasnoyarsk, designs of analogues and experimental developments of a hole-forming device. An analysis of the designs of similar devices made it possible to identify the advantages and disadvantages and take into account the development of new equipment for the hole former, determine the design and parameters of the device to optimize the technological process of sowing seeds in cassettes, achieve a device productivity of 20 cassettes / min. That allows to achieve the productivity of the entire complex up to 1200 cassettes per hour (100 thousand seeds per hour), which exceeds foreign and domestic analogues.

Currently, a promising direction is the cultivation of planting material with a closed root system (ZKS). In many countries (Finland, Sweden, Norway, Canada), reforestation and afforestation is carried out mainly with seedlings with a closed root system. Greenhouse complexes have been created in the countries of Europe, America and Asia, in which all methods of growing ZKS are performed. There are nurseries in Russia that mainly use foreign equipment for sowing seeds. One of the ways to solve this problem in Russia is the development and implementation of an import-substituting set of equipment for growing seedlings with a closed root system in greenhouses. An important device of this complex is the equipment for grinding the pressed substrate. The article presents an analytical review of existing analogues of equipment (Russia, Sweden, China) for grinding a pressed substrate for sowing seeds in cassettes. Both advantages and disadvantages have been identified. In the course of research and development, 3D models of a device for grinding a substrate for sowing seeds for growing seedlings with a closed root system were developed, the number of cutters was substantiated, productivity was calculated, parameters were optimized taking into account the experience of foreign and domestic analogues.

The pulp and paper industry is one of the basic branches of the economy, it plays an important role in improving the scientific and technical level of almost all sectors of the economy. The main source of raw materials for this industry is coniferous wood.The huge base of natural resources attracts investments in this industry, stimulates the growth of production. In Russia, an extensive model of forest management is mainly used, i.e. natural forest is being cut down. The difficulty of restoring forest resources in a natural way is that this process takes a lot of time and there are various factors on which the speed of restoration of forest ecosystems depends.

The paper considers a method for obtaining fine-dispersed cellulose from an alternative source of raw materials to wood and factors influencing the development of a fibrous suspension in a disc mill. The value of the degree of polymerization of cellulose that has previously passed the grinding stage, with different degrees of grinding on the Shopper– Rigler scale, is analyzed.