Izvestia Sankt-Peterburgskoj lesotehniceskoj akademii
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Fractional composition of tree litterfall and its carbon content in spruce forests in the Vepssky Forest Nature Reserve
Tree litterfall plays an important role in the carbon cycle of forest ecosystems. The aim of this work was to evaluate the fractional composition of tree litterfall and carbon in blueberry-sphagnum and blueberry old-growth and secondary spruce forests of the Vepssky Forest Reserve situated in the Leningrad region, Russia. The amount of annual tree litterfall in various forest types varied from 1.44 to 2.62 t ha–1 year–1, averaging 2.10 t ha–1 year–1. Needles and leaves represented the greatest part of tree litterfall – 52% in the old-growth forests and 70% in the secondary forests, respectively. The litterfall in the old-growth forests had three times greater content of generative organs (16%) compared to the secondary forests (6%). The carbon content in the main part of the tree litterfall (62% of the mass of the litter) varied from 47.5 to 49.5%. The smallest part – 27% of the tree litter mass – contained 50.1-51.5% of carbon. The carbon content in needles and leaves increased in the raw “aspen leaves (47.5%) – spruce needles (48.3%) – birch leaves (49.1%) – pine needles (51.4%)”. The amount of carbon entering to the forest floor with tree litter in the old-growth forests was 0.69 and 1.02 tC ha–1 year–1; in secondary forests – 1.10 and 1.30 tC ha–1 year–1, respectively.
Population of common oak (Quercus robur) in the widening of the Luga River floodplain (Luzhsky district of the Leningrad region): dendrological, phytopathological, soil-ecological characteristics
This study aims to provide a comprehensive dendrological, phytopathological, and soil-ecological analysis of the English oak (Quercus robur) population within a natural habitat at the northern extreme of its distribution. The habitat in question lies in the southern taiga subzone, specifically an extension of the Luga River floodplain near its confluence with the Kemka River. The focus is on old-growth trees, particularly late-generational and subsenile individuals. A preliminary survey identified 31 English oak trees affected by seasonal spring flooding in the area. A detailed investigation was conducted on the four subsenile-aged trees, ranging from 84 to 134 years. These trees occupy distinct microhabitats: Tree N 1 grows on an alluvial riverbank uplift; Tree N 2 – on a flat isthmus within the central floodplain zone; Trees N 3 and N 4 are situated in a terrace depression sloping toward a bedrock bank. The trees represent three ecotypes – forest (Trees N 1 and N 4), floodplain (Tree N 2) and intermediate (Tree N 3) – and include different biotypes. Three are classified as summer forms (N 1, 3, and 4), while one is a winter form (N 2). All trees are located primarily in well-drained zones despite the periodic flood conditions. Under the tree canopies, oak regeneration appears robust and plentiful. However, young saplings face competition from shade-tolerant broadleaved species – such as linden, maple, elm, and aspen – as well as boreal and nemoral shrubs. Phytopathological assessments concluded that the trees are generally in good health, with an average condition score of 2. Notably, these natural forest oaks undergo self-regulated crown cleansing rather than human intervention, such as pruning. Central rot caused by the polypore Laetiporus sulphureus was identified in most trees except for Tree N 2, which represents the winter form. The soils in this area are classified as alluvial soddy acidic soils, shaped by short-term seasonal flooding. They possess a well-developed humus horizon and exhibit high fertility levels that surpass those of typical podzolic soils found in southern taiga floodplains. This fertile soil underpins a diverse ecosystem typical of northern oak forests. The site encompasses geobotanical features representative of lily-of-the-valley oak forests, sedge oak forests, and slope nemoral grass forests dominated by spruce and linden. While the central floodplain oaks are likely of anthropogenic origin, the other mature specimens reflect habitats where natural regeneration of English oak occurs consistently without human interference. This location serves as an illustrative fragment of northern oak forest ecology, encapsulating key environmental dynamics of this habitat type.
Analysis of potential recreational load on Moscow’s specially protected natural areas
The article presents a methodology for calculating the potential recreational load on Moscow's specially protected natural areas according to MGSN 1.02-02. The calculation was performed for three Moscow specially protected natural areas: Severnoye Tushino Nature Park (Aleshkinskiy forest territory), Shchukinskiy forest park and Vsekhsvyatskaya grove, and Vorobyovy gory nature reserve. The potential recreational load was determined using the QGIS program, which was used to plot isochrones to determine the transport accessibility of the selected areas (10 and 20 minutes' drive from the central point of the park). The list of specially protected natural areas located within the accessibility zone of the designed area was compiled based on open data using the GIS OGD portal. The conclusion on the potential recreational load on the areas selected for analysis was compiled based on Table 4.5 of MGSN 1.02-02. During the study, it was established that the potential recreational load on the territory of the Vorobyovy gory Nature Reserve exceeds the permissible level.
The use of environmentally friendly preparations to stimulate the growth and development of Pinus Sylvestris L. seedlings
The study of the effect of growth stimulants on the quality of planting material for reforestation purposes has great practical importance. Growth-stimulating drugs help accelerate the processes associated with the growth and development of plants, as well as improve their adaptation to environmental factors. The research was carried out in the protected soil of the Vologda Breeding and Seed Forestry Center nursery, located in Kadnikov, Vologda region. As stimulators of seed germination and activation of seedlings of Pinus sylvestris L. technical lignosulfonates (chlorinated and nitrosated) of 10% concentration; birch bark extract (fraction less than 1 mm and fraction more than 1 mm) with a concentration of 1:10000; filtrate obtained by separating suberin from birch bark with a concentration of 1:10000; “Flavobacterin”; “Mizorin”; condensate formed during drying of lumber; the ashes of Ejyafyadlajyokyudl volcano were used. It was found that by 10-15th day of cultivation, the best results were shown by seedlings of seeds treated with chlorinated and nitrosated lignosulfonate solutions (70-94% of seedlings). Seedlings of seeds treated with filtrate solutions from the release of suberin from birch bark, condensate from drying wood, ash from the Ejyafyadlajyokyudl volcano, “Mizorin” and “Flavobacterin” prevail 1.5 times on the 15th day after sowing compared with the control variant. It was noted that the highest average height (12.30±0.32 cm) was observed in seedlings treated with a solution of chlorinated lignosulfonates; the maximum average diameter (2.19±0.25 mm) and root length (17.90±0.26 cm) were recorded in pine specimens treated with “Flavobacterin”. It was found that the yield of standard seedlings increased to 96–99% with the use of lignosulfonates, extracts of birch bark fraction less than 1 mm, condensate solutions, “Mizorin”, “Flavobacterin” and ash from the Ejyafyadlajyokyudl volcano, while in the control area, this figure was only 40%. If the recommended methods of using stimulants are followed, the need for seedling growth is eliminated, which significantly reduces the cost of planting material production.
Current problems of spruce stands regeneration in the Volga Federal District
Spruce stands comprise one-fourth of the total forested area in the Volga Federal District. Amid contemporary global transformations and the economic activity not consistently grounded in scientific principles, there is a reduction in the forest cover and in their ecological and resource potential. The challenges of reproducing spruce stands in the Volga Federal District can only be addressed by leveraging the extensive knowledge of past foresters alongside contemporary advancements. The research aims to identify the most efficient methods for regenerating spruce stands in the Volga Federal District, enhancing production and biological resilience of the plantations while minimising economic expenditures. The data collected are derived from the analysis of research literature, the state forest register, and our own research findings obtained at stationary experimental plots established in the Educational-experimental and Pektubayevsky forestry enterprise of the Republic of Mari El. At each location, an evaluation of the condition, size structure, and production of the stands was conducted using conventional forest inventory methods. The obtained digital data has undergone statistical analysis. The key problems have been identified, and ideal strategies for the regeneration of spruce stands in the Volga Federal District have been delineated, categorised by natural and economic zones: southern taiga, coniferous-deciduous forests, steppe, and forest-steppe. In each instance, it is essential to optimise the methods and strategies of reforestation. In order to properly maintain the spruce stands in the Volga Federal District, the following factors are crucial: a zonal strategy that considers forest conditions and the composition of the forest stand; the advancement of plantation forestry on former agricultural lands, focusing on obtaining paper wood, bioenergy, and carbon initiatives; enhancement of planting density and standards of planting material in alignment with regional characteristics.
Diagnostics of one- and two-year-old seedlings of curly birch using the molecular marker BPCW1, which correlates with the “patterned wood” trait
The results of diagnostics of curly birch (Betula pendula Roth var. carelica (Mercklin) Hämet-Ahti) are presented among one- and two-year-old seedlings obtained as a result of open pollination of trees growing in the Leningrad Region on the territory of the Gatchina PLSU. Using the BpCW1 molecular marker, it was possible to identify potential carriers of figured wood among seedlings already in the first year of life, although its indirect characteristics become apparent in trees on average at the age of 8 years or later. It was shown that 23 of the 95 seedlings studied (24%) contained amplification products (476 bp or 476/530 bp) characteristic of curly birch. It was established that the allele containing the deletion is represented mainly (91.3%) in the heterozygous (476/530 bp) state and only a small percentage (8.7%) in the homozygous (476/476 bp) state, regardless of the age of the seedlings. However, the number of potential carriers of patterned wood is 3.6 times higher among two-year-old seedlings than among one-year-olds. It is hypothesized that the small proportion of plants with patterned wood in the seed progeny of curly birch is due, on the one hand, to their origin (from open pollination) and, on the other, to the specific histogenesis of seedlings during the first two years of their development. Analysis of growth indicators shows that two-year-old plants significantly exceed one-year-olds in average height and diameter (sixfold and threefold, respectively). Based on the conducted work, it is concluded that the use of open-pollinated seeds for growing curly birch planting material is feasible, provided that carriers of the “patterned wood” trait are identified among them using the BpCW1 molecular marker. This is virtually impossible to achieve at an early age using other methods based solely on the analysis of external (morphological) or physiologicalbiochemical characteristics. In the future, this method can be used both for solving scientific problems and for practical use.
Changes in the biological activity of soils when adding superabsorbing polymers to them
Due to global climate change, which entails redistribution of intra-annual precipitation, there are continuous periods of draught, which were not typical for this territory before, which directly affects the water availability of agricultural crops. The solution of this problem is in development of various technologies and functional materials. One of such materials are superabsorbent polymers or hydrogels. Many studies prove that hydrogels favorably affect the yield of agricultural crops, due to their ability to absorb water in a volume exceeding its own in several tens of times, thereby retaining moisture in the root layer, preventing it from evaporating and flowing to deeper layers of soil. Three types of hydrogels were used in the experiment: «Ritin-10», «Aquasorb», «B415-K» – and sod-podzolic soil from the Menkovo branch of the Agrophysical Institute in the Leningrad region. Microbial metabolic coefficient (qCO2) is an integral indicator of the biological state of soils. It reflects the change in basal respiration and microbial biomass of the soil: the lower the value is, the better the condition of the microbial community is. In the control samples there was an increase in the value of the indicator by day 30, in the samples with hydrogels this indicator decreased by day 30. For all samples with hydrogels there was a noticeable decrease in the index and, consequently, an improvement in the state of microbiota occurred between day 15 and 18 of the experiment. In this experiment, is impossible to reliably establish whether hydrogel becomes available for microorganisms as a source of elements necessary for life activity, but its presence in the soil improves the state of microorganisms, and in case of hydrogel «B415-K» also contributes to the increase of biomass of microorganisms.
Composition and productivity of forests in tectonic nodes in the Arkhangelsk region
The purpose of the work is to study the influence of the geological component, in particular tectonic knots on the rock composition and productivity of stands of the Arkhangelsk region. Tectonic knots (hereinafter referred to as knots) were distinguished by a set of geophysical data, a hydraulic network and a mesorelief. Knots are the site of the suppression of 2 or more deep faults of the Earth's crust, in which the fragmentation of the Earth's crust is increased. As the number of intersecting faults increases, the permeability of the Earth's crust increases, which leads to increased geophysical anomalies, deep degassing, and changes in the structure of the baric field. In total, 3 knots with a significant area and fragmentation of the Earth's crust were studied. The initial forest management data was the forest management plan and tax descriptions for 1995. The rock composition was studied in 3 knots on an area of more than 11,000 km2, and the productivity of pine forests was investigated in the Velsko-Ustyansk knot. A reliable direct correlation of the proportion of spruce with the geomorphometric parameters of the Kozhezersky knot was revealed, which is associated with an improvement in soil and soil conditions due to improved drainage by means of a high dissection index. The inverse correlation of the proportion of pine and birch in this node with the same parameters is due to the displacement of these species by spruce. The direct correlation of the proportion of marshes with the height of the terrain in the Velsko-Ustyansky knot is most likely due to the widespread distribution of moraine sand deposits and less precipitation in the center of the knot, since the relief is less pronounced than in Kozhezersk. The influence of the VelskoUstyansky knot on increasing pine productivity is no more than 10% and is expressed in an increase in height, diameter, or both by 1-2 m and 1-2 cm, respectively, which is associated with a decrease in precipitation in the center of the knot and an improvement in soil and hydrological conditions. The data obtained allow us to talk about the possible influence of tectonic knots on the rock composition and productivity of coniferous plantations, by changing climatic and geoformometric parameters.
Assessment of the prospects of using topiary forms of coniferous plants in the conditions of the city of Saratov
The article is devoted to current research on the formation of topiary from coniferous plants, as an element that increases the decorative qualities of landscaping objects throughout the year due to the diverse coloring of needles from green to blue. The authors presented an analytical review, according to which data on the influence of geographical origin on winter hardiness and drought resistance of varieties of Juniperus and Thuja species are limited in the conditions of Saratov. The purpose of the study was to assess the nature of growth and development of Juniperus and Thuja species and varieties after shearing, plant resistance to a complex of adverse factors in the conditions of Saratov. The prospects for the introduction of woody plants were determined by the method of integral numerical evaluation, developed in the Department of Dendrology of the SBS of the USSR Academy of Sciences. The prospects of the introduction were determined by the sum of the scores of the indicators and the scale. Species composition of phytopatogens of Juniperus and Thuja varieties and forms in the conditions of Saratov was determined by the macroscopic method. Studies are presented concerning the necessity and optimal frequency of pruning of conifers adapted to the stressful conditions of the urban environment. In the conditions of Saratov, for varieties of Juniperus and Thuja species, molding pruning based on the conducted studies is recommended in early spring before May 15 or at the end of summer. In autumn, only broken branches and bald shoots are cut off from coniferous plants. The studied species have sizes and shapes close to the natural ones characteristic of individuals within the range. All the studied varieties of thuja and juniper are classified as quite promising.
Isolation and selection of valuable forms of common hazel (Corylus avellana L.) in the Voronezh region
Common hazel is a particularly valuable species that combines a range of useful properties. Fruit plantations are created in all regions with suitable climate and soil conditions; the crop is used in protective forest plantations and in landscaping urban and suburban areas. Breeding a variety pool is promising using the local gene pool of wild forms when selecting individuals with economically valuable traits, which determines the relevance of the issue under study. The objective of the work is to identify and select the most valuable forms of common hazel based on a comprehensive analysis, suitable for various purposes when grown in the Voronezh Region. The objects of the study were forest stands of different ages growing in various types of forest growth conditions in the Prigorodnoye forestry of the Voronezh Region, differentiated by hazel density. The studies were conducted using both generally accepted methods for the selection process and the author's methodological approaches. The selection was based on adaptive, reproductive and ornamental properties. Promising forms of common hazel were identified based on various most important selection traits: forms A1, A5, B2, B3, and D5, which can be used to create nut-and-fruit plantations, ornamental afforestation, and to increase biodiversity and sustainability of ecosystems. Forms A1 and D5 are recommended to increase biodiversity and form sustainable forest plantations. Reliable differences were revealed between the average values of winter hardiness and disease and pest resistance traits. Forms B2 and B3, given the increased values of individual fruit quality elements, are recommended for cultivation in garden plots, and form B3, with proper selection measures, is recommended for creating fruit plantations.
Taxus baccata L. and Acer trautvetteri Medw. on the northern macroslope of the Caucasus
The article presents comparative data on the species composition of the vegetation of the middle belt of mountain forests on the northern macroslopes of the Caucasus. The purpose of the study is to compare the species composition of plants according to the components of the phytocenosis in the vertical zone of Taxus baccata and Acer trautvetteri. The object of the study is forest formations with Taxus baccata and Acer trautvetteri at an altitude of about 1100 m above sea level. The vegetation was studied simultaneously for all components of the phytocenosis on circular accounting sites with a radius of 178.5 cm in accordance with Russian Patent № 2852509. The maple forests are represented by mixed-species stands: 59% – Acer rautvetteri Medw., 14% – Fagus orientalis, 11% – Alnus glutinosa, 8% – Ulmus laevis, 6% – Acer platanoides, and 3% – Fraxinus excelsior. In the stands where yew grows, the common hornbeam dominates, accounting for 66% of the total wood stock. The saplings in maple forests consist of 8 species, with a predominance of Acer platanoides, while the saplings in beech forests consist of 3 species, with a predominance of Quercus petraea. The undergrowth in maple forests is more diverse than in beech forests, with 8 species compared to 4 species. The living ground cover consists of 16-20 species. The species diversity coefficient ranges from 0.33 to 0.45. The coincidence of the upper distribution zone of the Taxus baccata with the lower belt of the Acer trautvetteri has been established. At the same time, maple grows mainly on the slopes of northern expositions, and yew under the canopy of stands – mainly on steep, inaccessible slopes of any exposure. The composition of stands, saplings, undergrowth, and living ground cover varies in the compared forest ecosystems. The co-occurrence of Taxus baccata and Acer trautvetteri has been recorded in the Zilakhar tract of the North Ossetian-Alania Republic at an altitude of 1100–1200 m above sea level. The results obtained can be used in the updating of forest plans and forest management regulations.
The response of biota to changes in climatic factors using the example of birch (Betula L.) phenorhythms growing in the forests of the Voronezh region
The study reveals the degree of influence of climatic influences on the tree species, the fluffy birch, which grows in the Voronezh region. The temperature of the atmospheric air can act as a determining indicator of the impact on vegetation. The purpose of the work is to analyze trends in the timing of the onset of vegetative phenological phenomena in comparison with the nature of climatic changes. The object of the study was the forest regional system of the Voronezh region, and the subject was the downy birch (Betula pubescens) and the correlation of its phenological rhythms with climatic indicators. The temperature of the atmospheric air was analyzed on a monthly basis, and the meteorological data were averaged over two basic climatic periods. Over the entire research period, there has been a shift in the dates of the beginning and duration of phenological phases and phenomena. In comparison with two basic climate periods (from 1961 to 1990 and from 1991 to 2020), there has been a change in the temperature regime in the region. The onset of spring phenological phases has been observed several days earlier than usual. There has been a direct correlation between the onset of sap flow, leaf expansion, and flowering, and the influence of air temperature. The response of the birch plantations demonstrated a strong correlation with atmospheric air temperature. Such studies are useful in selecting the range of reforestation in the context of climate change in the region. The shift in phenological rhythms can be considered as a bioindicator of climate change on Earth.
Contribution of Tree Regeneration to the Formation of Fuel Complexes and Carbon Emissions from Fires in the Minusinsk Ribbon-like Pine Forests of the Krasnoyarsk krai
Forests occupy a significant proportion of the Earth's land surface and act an essential role in accumulating atmospheric carbon. Under conditions of global climate change, forest fires and pyrogenic emissions are increasing, particularly in Siberia. The purpose of this study is to assess the role of Scots pine (Pinus sylvestris L.) regeneration in the formation of forest fuel complexes (FFC) and to estimate carbon emissions from the combustion of FFC in the Minusinsk Ribbon-like Pine Forests. The research was conducted on two sample plots of Scots pine regeneration of combined (SP1) and natural (SP2) origin, formed after the fire of 2007 and re-burned in 2022. In addition, control forest plots that did not burn in 2022 were investigated. It was found that postfire reforestation on the sample plots is successful, with the number of trees reaching 21.5 and 16.3 thousand individuals/ha on SP1 and SP2, respectively. The total phytomass of model pine trees is 50-330% higher on the area with natural post-fire regeneration (SP2) than on the sample plot with combined regeneration (SP1). The total loads of regeneration and ground fuels were 38.3 t/ha and 32.5 t/ha, with the phytomass of regeneration accounting for 77% and 73% on SP1 and SP2, respectively. The fires consumed 11.9 and 13.8 t/ha of organic matter, with a pyrogenic emission of 5.17 tC/ha for SP1 and 6.15 tC/ha for SP2. The contribution of regeneration to fire carbon emissions was 29% for SP 1 and 43% for SP 2, with burnt needles accounting for 22% for SP 1 and 35% for SP 2, which is associated with a more developed tree crown on SP2. Overall, despite the fact that pine ribbon-like forests are characterized by high firefrequency, the forest-growing characteristics of the region and the frequent landscape fires inhibit the accumulation of significant forest fuels, resulting in lower fire emissions per unit area compared to the southern and central taiga zones of Siberia.
Development of molecular genetic markers of genes encoding adaptive response methods in pine
Under the conditions of global climate change, which leads to increased frequency of droughts, frosts, and pest outbreaks, the breeding of Scots pine (Pinus sylvestris L.) for enhanced resilience is an urgent task. Marker-assisted selection (MAS) is a promising tool for accelerating the breeding process, requiring the development of molecular markers associated with adaptive traits. The aim of this study was to develop and preliminarily test such markers. Due to the lack of a whole-genome reference assembly for Scots pine, a candidate-gene approach was employed. The study focused on genes whose homologs in related species are associated with adaptation: PRR1 and PRR7 (components of the circadian clock involved in response to photoperiod and temperature stress), dhn1 (a dehydrin conferring resistance to dehydration), as well as the mitochondrial genes COX1 and ATP-A (phylogenetic markers). Based on polymorphisms (SNPs and a deletion) identified by sequencing, 4 KASP and 1 STS markers were developed. Their testing was conducted on geographical cultures of pine using a sample of 100 trees from four climotypes (Leningrad Region, Karelia, Estonia, Udmurtia). Statistical analysis using Fisher's exact test revealed a significant difference (p ≤ 0.05) in allele frequencies of the PRR7 gene between the Karelian and Udmurtian climotypes, indicating a potential longitudinal cline for this locus and its potential informativeness for assessing adaptive population differentiation. For the other genes, no clear associations were established within this sample. The results demonstrate the effectiveness of the candidate-gene approach for the initial stage of developing molecular markers for adaptation in Scots pine and lay the groundwork for further research to establish reliable phenotype-genotype linkages with the aim of subsequent application in breeding programs to create resilient planting material.
Development and study of mathematical model of pneumatic vehicle of a lower pressure and soil interaction
This study examines the interaction of pneumatic vehicles of a lower pressure of forestry machines with soil surfaces with reduced bearing capacity. Mathematical modeling and numerical methods were used to implement the developed mathematical model, and a computational experiment was conducted. The study showed that for pneumatic vehicles of a lower pressure on Category III forest soils (“classic” weak forest soils), as well as on more concrete surfaces, the tire bearing capacity is the limiting factor for the vehicle weight. For a standard-size tractor wheel, the bearing capacity weight limitation is observed for soil conditions close to Category II (medium-strength forest soils) or higher. Processing the calculated data revealed a linear function for the tractor's traction and thrust properties at a weight limited by a rut depth of 0.2 m or, for more durable soil surfaces, by the tire's bearing capacity. It was established that, while adhering to the rut depth and bearing capacity limitations, the tractor possesses drawbar-pull coefficient estimate that is a quadratic function of the soil deformation modulus. This is advantageous from a technological perspective, as the presence of isolated obstacles is likely along the vehicle's path. Formulae for calculating the rolling resistance coefficient, net thrust coefficient, and drawbar-pull coefficient for the specified tractor weight limitations are presented for practical purposes. Comparison of the results of the computational experiment implementing the model for standard forestry tires and low-pressure pneumatic tires showed that, with an acceptable vehicle weight, the drawbar-pull of the pneumatic vehicle on the soil is comparable to that of a standard one, while the rolling resistance coefficient decreases by an average of 39%, and the drawbar-pull coefficient increases by an average of 43%.
Feasibility study of the feasibility of using sand and gravel mixture in road surfaces during transport development of the timber resource base in the north of the Republic of Karelia
Defects and unevenness of the road surface reduces the speed of transportation of forest raw materials by 30-35%, increasing the cost of transportation by 50-60%. In areas with low bearing capacity of soils, which are overwhelmingly typical for the Republic of Karelia, this problem is aggravated by the presence of elevated groundwater levels and, as a result, deeps and subsidence of the roadway. Reducing the likelihood of such defects is possible when using local stone materials. Such a material for the Republic of Karelia is a sand-gravel mixture (SGM) obtained in its natural state. The technology of construction of logging roads using gravel mixes requires studying it for compliance with standards in existing and potential quarries, analyzing the location of mining sites, and the possibility of delivering it for the construction and repair of forest roads. The article analyzes the geography of the location of sand and sand-gravel mixture extraction sites in the Republic of Karelia, presents the results of a study of its qualitative properties, evaluates the technical and economic efficiency by calculating and comparing the estimated cost of crushed stone and SGM during construction, depending on the transport and logistics scheme of their delivery.
Method for measuring the width of a stack of round timber placed between stakes
For the logging and timber processing industries of the Russian Federation, which carry out assortment logging and use round timber (logs) for processing, it is important to use the least expensive methods for measuring their volumes, with an error rate acceptable for production. These include the group (geometric) method for measuring the volume of round timber stacked in a pile. The main difficulties in determining the volume and the convergence of measurement results arise when moving timber from the supplier to the recipient, which is loaded in piles on road and rail transport. These volumes are submitted by the participants of the timber turnover process to the Federal State Information System for Forestry of the Russian Federation, where they are controlled and accounted for by the Federal Forestry Agency. To improve the accuracy of determining the dense volume of a timber stack, it is necessary to properly measure its components, including the width. This article proposes a method for measuring the width of stacks and fences.
The problem of corrosion resistance of structural elements of forestry machines in industrial mechanical engineering
This paper presents a review of the corrosion effects on structural components of forestry machinery. The material presented is based on literary sources on the types of metal and alloy corrosion, its mechanisms, causes, consequences, and protection methods applied to forestry machinery. The purpose of this paper is to analyze and summarize the results of scientific research on the problem of corrosive destruction of structural components of forestry machinery, as well as to identify promising research areas for improving the protection of forestry machinery from corrosion. A classification of corrosion types is presented. The article examines the effects of gas, atmospheric, soil, and other types of corrosion on forestry machinery components, and provides examples of machine structural components susceptible to this phenomenon. Illustrations demonstrating corrosion processes obtained by the authors at enterprises in the forestry complex are presented. Based on the material presented in this paper, it is concluded that the problem of corrosion effects on the structure of forestry machinery is complex and requires a comprehensive approach ensuring corrosion protection at all stages of the equipment's life cycle. Existing scientific literature largely addresses corrosion protection during the operational phase of forestry equipment, particularly during off-season storage. Less attention is paid to addressing the issue during the design and engineering stages. The authors conclude by highlighting a number of promising research directions in this area.
Analysis of raw materials supply options for the newly established enterprise for low-grade hardwood processing
Using the simulation model of transportation flows for timber transportation, developed by the author and implemented in the AnyLogic software environment, which employs a combination of agent-based and discrete-event modeling, an analysis was conducted on various options for organizing the supply of raw materials for the newly established enterprise focused on processing low-grade hardwood. This new facility is intended for the production of bleached chemical-thermomechanical mass, which will subsequently be utilized for the manufacture of paper dishes, cardboard packaging, napkins, and more. A comparison of different alternative scenarios, based on the involvement of varying numbers of forestry areas located in relative proximity to the planned facility, leads to the conclusion that the preferred scenario is one in which raw material supplies are sourced from two forestry enterprises – Suoyarvsky and Pryazinsky.
Promising areas of modeling the structure of intraregional and interregional timber transportation flows in the context of Western sanctions pressure
The article is devoted to the analysis of promising areas for optimizing logistics chains in the timber industry, taking into account geopolitical, economic and environmental challenges. This information is especially relevant in the context of Western sanctions pressure on Russia. The aim of the work is to reorient the existing system of modeling the structure of intraregional and interregional forest transportation flows, with an increase in the resilience of the forest sector to changing external geopolitical conditions. Special attention is paid to the current state of the system of modeling transport and logistics chains of the forest complex. The features of traffic flow modeling are investigated, taking into account regional specifics and new geopolitical realities. The article considers the need to reorient timber export flows from traditional markets (EU) to new ones (China, India, Middle East countries), as well as prospects for the development of transport infrastructure and deep processing of wood. The paper presents an analysis of the Russian timber industry by federal districts, including data on the forest fund, harvesting volumes, export directions and key issues. Based on this analysis, the main disadvantages of existing models of forest transportation flows are highlighted, such as lack of flexibility, insufficient consideration of environmental restrictions and the dynamics of sanctions risks. The most probable and promising areas of model improvement are proposed, including the integration of GIS technologies, agent-based approaches, and the development of multimodal routes (rail, river, and sea). The recommendations of the article are aimed at increasing the sustainability of the timber industry through the acceleration of deep processing programs, the development of alternative logistics corridors and the coordination of interregional supplies. The study may be of interest to logging companies exporting and processing timber, as well as universities that train personnel in the timber industry.
Methodology for determining the power characteristics of digging on-site using organic digging equipment during the preparation of large-sized planting material
Large-sized planting stock is a special type of product from forest and ornamental nurseries, widely used in landscaping and greening. In forestry, large-sized seedlings have potential for use in establishing forest seed plantations and reforestation within urban areas. Harvesting large-sized seedlings requires specialized digging equipment, allowing for mechanized harvesting of seedlings while preserving the root ball during digging. The aim of this study is to develop a method for determining the principal moment of resistance of the digging tool, which rotates around a fixed axis during digging. Determining the principal moment of resistance of any soil structure, including those containing plant inclusions (e.g., roots), requires a series of experimental studies. Soil resistance forces vary depending on the position of the digging tool, and a differential equation for the change in kinetic momentum is used to mathematically describe the rotation process. During one cycle (rotation of the working element), the pressure force in the hydraulic cylinder and the piston speed of the hydraulic cylinder are experimentally determined. Based on laboratory experiments, the relationships of several key kinematic and force characteristics were calculated for the developed excavating machine: rotation angle, angular velocity, angular acceleration, and the moment of soil resistance relative to the axis of rotation of the working element. The developed methodology is applicable to assessing the force characteristics of other technological machines with similar operating processes (earthmoving, road construction, etc.). The data obtained from the calculations can be used to optimize the design parameters of the developed equipment.
Application of the graph-analytical method to optimize the operation of a forwarder during clear-cutting logging
In modern conditions, when the economic sector of the industry is in a difficult situation, increasing the efficiency of logging equipment and optimizing its operation is particularly important. High-quality preparation of territories, optimization of the technological process of logging and the correct selection of machine systems for work in logging areas make it possible to increase the efficiency of logging enterprises. This article discusses the issue of using the graphoanalytical method on continuous logging using Scandinavian technology using a harvester and forwarder. In the research, a real logging area in the Northwestern Federal District was processed, the forest area is represented as a weighted graph. To process the results, specialized applications were used to shorten and automate the process. The transformation of a cutting area into a graph with connected vertices is presented. Formulas are derived to determine the minimum distance traveled according to the “nearest neighbor” principle. An objective function is presented to determine the task, which boils down to solving the traveling salesman problem. Using the proposed method allows forwarder operators to recommend specific technical tasks with route optimization, reducing the likelihood of accidental relocation operations. Given the difficult economic situation in the forestry sector, the application of this approach to work design may allow loggers to optimize the operation of skidding equipment and increase the efficiency of logging production in general. The considered and derived provisions on finding the optimal path when working with a middle-class forwarder on a weighted graph in the form of a cutting area, allows us to develop this topic in the future with the processing of a large array of cutting areas. Expanding the database of multiple cutting areas and processing information in general will also make the model under consideration more adequate and sustainable for various types of cutting areas.
Overcoming a slope with a model of an autonomous articulated skidder
The paper provides a rationale for developing a technical solution based on an autonomous articulated carriage. A radio-controlled model of an articulated carriage at a scale of 1:16 has been manufactured. The process of the carriage passing along the The paper provides a rationale for developing a technical solution based on an autonomous articulated carriage. A radio-controlled model of an articulated carriage at a scale of 1:16 has been manufactured. The process of the carriage passing along the
Technological aspects of biodiversity conservation measures during logging operations contained in the forestry regulations of the forestry districts of the North-West of the Russian Federation
The work is devoted to the study of technological aspects of biodiversity conservation measures during logging operations contained in the forestry regulations of the forestry districts of the North-West of the Russian Federation. This issue seems to be very important to the author, because it is precisely because of the lack of design and the failure of loggers to take measures to protect wildlife and their habitat they have to pay for the damage. The purpose of this study is to analyze the measures for the conservation of biodiversity during logging operations contained in the forestry regulations of the forestry districts of the North-West of the Russian Federation in order to determine the technological features of their implementation by loggers. Research objectives: to analyze the modern regulatory and methodological framework for biodiversity conservation measures during logging operations; to analyze the practice of carrying out measures for the conservation of biodiversity during logging operations in the conditions of forestry in the North-West of the Russian Federation; based on this analysis, to determine the technological features of measures for the conservation of biodiversity during logging operations in the conditions of forestry in the North-West of the Russian Federation. As a result of a joint analysis of the technological features of biodiversity conservation measures during logging operations in the forestry areas of the North-West of the Russian Federation, using the example of the Priozerny Forest District of the Arkhangelsk Region and the Borovichi Forest District of the Novgorod Region for a number of biological diversity sites, it was found that the predominant biodiversity conservation measure is the establishment of buffer zones, and with regard to logging technology, a number of restrictions, among which: no logging, no laying of portages, non-placement of loading platforms within the boundaries of the facility; high stumps and fallen trees should be preserved outside the technological network; the need to dismantle crossings through temporary watercourses after the development of the cutting area in order to ensure the flow of water and not clutter the riverbed, etc.
Production of fibrous materials by combined cooking of technical hemp processing waste
The purpose of the work is to evaluate the effectiveness of testing combined two– stage sodium oxidative-organosolvent cooking of industrial hemp processing waste for the production of cellulose. The component composition of the raw material: the mass fraction of resins and fats is 1.9%, substances soluble in hot water are 3.4%, cellulose is 56.7%, lignin is 21.7%, ash is 1.1%. Conditions of sodium cooking: hydromodule – 5:1; consumption of NaOH – 20...24% in units of Na2O, % of abs. dry raw materials; temperature rise to 170 °C – 40 min; cooking at 170 °C – 120 min. Conditions of oxidative-organosolvent delignification: consumption of equilibrium peracetic acid – 0.8 g/g abs. dry raw materials, hydraulic module – 10:1, temperature rise to cooking – 15 min, cooking temperature – 90°C, duration – 90 min. At the first stage (alkaline cooking), 2.8 to 3.2% of carbohydrates are destroyed per one percent of the removed lignin, depending on the consumption of active alkali. At the second stage, during the temperature rise to the cooking point, there is a significant decrease in the concentration of cooking components: RPA decreases by 2.5-3.9 times, and H2O2 by 1.6-2.3 times, depending on the consumption of RPA for an absolutely dry soda semi- finished product. The main stage of delignification is characterized by the complete expenditure of RPA. For all variants of oxidative-organosolvent delignification, the reaction rate constant is (2.8 ± 0.2) × 10–1 s–1. During step-by-step cooking of cannabis processing waste with an alkaline cooking duration of 120 minutes at an alkali consumption of 24% in units of Na2O from abs. dry. raw materials and subsequent oxidation-organosolvent delignification within 30 minutes can produce technical cellulose with a yield of 54.9% of the mass of abs. dry raw materials with a mass fraction of lignin of 3% and alpha-cellulose of 88.9% of technical cellulose.
Co-pyrolysis of biomass with technical glycerin
The forest industry complex in Russia plays a key role in the economy, but the efficient utilization of wood waste remains a pressing issue. Biomass, including forestry waste, is an important renewable resource for producing liquid, gaseous, and solid fuels. However, traditional biofuels have drawbacks, such as high viscosity, corrosive activity, and low stability. This study investigates the co-pyrolysis of wood with technical glycerin to enhance the process efficiency and improve the properties of the resulting fuel. Experiments were conducted using a bench-scale thermogravimetric analysis setup. The raw materials used were birch wood and sawdust impregnated with glycerin (20–40%). The pyrolysis process was carried out at temperatures up to 700°C. The resulting products (char, condensate, and gas) were analyzed for calorific value, sulfur content, moisture, and ash content. The chemical composition of glycerin and pyrolysis products was studied using gas chromatography and mass spectrometry (GC/MS). The addition of glycerin increased the yield of condensable products to 63.4% (compared to 28.7% without glycerin) and reduced the share of gases and losses to 17.45% (compared to 44.8%). The heavy fraction of the condensate demonstrated a high combustion heat (39,920 kJ/kg) and low sulfur content (0.02%), outperforming fuel oil, coal, and firewood. Co-pyrolysis of biomass with glycerin is a promising method for producing high-energy and environmentally friendly fuel. The results demonstrate the potential for industrial application of this technology, including use in thermal power plants and heating systems. Further research may focus on optimizing process parameters and scaling up the facilities.
Review of studies on the extraction of pectin and by-products from non-wood parts of coniferous trees
The special characteristics of conifers determine the complexity of their study and their great importance from various points of view. Conifers are generally considered to be one of the most difficult lignocellulosic raw materials for the extraction of biologically active substances suitable for fermentation, primarily due to the nature and amount of lignin. In terms of chemical composition, conifers contain a large number of valuable biologically active substances: pectin, pine wax, anthocyanidin dye. Pectin protects cells from oxidative stress, promotes rejuvenation and strengthens the immune system; pine wax is a promising component for the cosmetic industry, possessing antiseptic, anti-inflammatory and moisturizing properties; anthocyanidin dye is widely used in the food industry, especially in the production of beverages, confectionery and dairy products, due to its naturalness, bright color and antioxidant activity. The paper presents the results of studies on the extraction of pectin and byproducts from the needles and bark of pine, spruce and larch growing in the Russian Federation and Europe, and a comparative analysis with the quality indicators of pectins from the peel, kernels and cake of apples, beet cake and lemon peel. It has been established that pectin from Scots pine wood greenery is characterized by the highest value of the complexing capacity indicator and the number of carboxyl groups, and has a low degree of esterification compared to fruit and berry pectins. According to the results of an analytical study on the extraction of pectin and by-products from non-woody parts of conifers, it was revealed that: various types of acids are used as the main extractants, such as nitric, hydrochloric, orthophosphoric, sulfuric, citric and an aqueous solution of ammonium oxalate; to assess the quality of the extraction of substances, various analytical methods and analysis techniques using modern equipment are proposed (to determine the degree of esterification – potentiometric titration, to study the sorption capacity of pectin – the method of reverse complexometric titration, etc.); there are no optimal technologies developed in industry. In this regard, the development of new technologies for the extraction of pectin and by-products from non-woody parts of coniferous trees is relevant.
Morphological characteristics of fibrous semi-finished products from sunflower husk Morphological characteristics of fibrous semi-finished products from sunflower husk
The problem of waste processing at oil processing plants and the urgent task of finding alternative sources of raw materials for the pulp and paper industry became the impetus for the development of methods for obtaining fibrous semi-finished products from sunflower husk. The method of alkaline-peroxide low-temperature treatment with subsequent grinding was used to obtain a fibrous semi-finished product of high yield (yield 82-86%), the method of alkaline-sulfite cooking was used to obtain cellulose of high yield (yield 56-68%). The study of the morphological characteristics of the fibrous semi-finished products obtained from sunflower husks showed that the mass of medium-fiber and long-fiber fractions suitable for paper production is about 50% in high-yield cellulose, and up to 70% in the fibrous semi-finished product of high yield. This allows us to consider these semi-finished products as potential raw materials in the production of paper and cardboard, taking into account modern achievements in paper technology, with the use of various chemical additives and methods for preparing paper pulp.
Preparation of Sulfonic Derivatives of Sulfate Lignin
Sulfate lignin is a large-tonnage by-product in the pulp production. It’s mainly used in black liquor recovery boiler in the production of sodium sulfide, and only a small part of it, due to its complex structure, is used in a chemically modified form. Nevertheless, sulfate lignin has the potential to synthesize sought after products with high added value. Unlike sulfate lignin, lignosulfonates, due to their individual physics-chemical properties, are in stable demand due to their use in various industries. However, the production of sulfite cellulose is disproportionately lower than that of sulfate cellulose, and as a result, the total number of commercial lignosulphons does not meet the needs of the market. Thus, there is an ambiguous situation – the underutilization of the potential of sulfate lignin in the synthesis of products with similar properties of lignosulfonates, against the background of an increased demand for lignosulfonates. The study shows the possibility of modifying sulfate lignin. The method of functionalization of the coniferous sulfate lignin structure, including the oxidation of hydroxyl groups with hydrogen peroxide or sodium hypochlorite, and their methylation with dimethyl sulfate, followed by the addition of sodium hydrosulfite to the formed carbonyl groups, made it possible to obtain a product soluble in acidic and neutral media. The obtained soluble lignin is almost identical in its physics-chemical properties to industrial liquid lignosulfonates, which makes it promising for use in similar technological processes.