Lesnoy Zhurnal (Russian Forestry Journal)

Lesnoy Zhurnal (Russian Forestry Journal)

Basic info

  • Publisher: Northern (Arctic) Federal University named after M.V.Lomonosov
  • Country of publisher: russian federation
  • Platform/Host/Aggregator: Open journal system ojs
  • Date added to EuroPub: 2019/Sep/27

Subject and more

  • LCC Subject Category: Forestry, Technology
  • Publisher's keywords: Forestry, Technology, Machinery of logging, timber processing and chemical treatment of the wood biomass
  • Language of fulltext: english, russian
  • Time from submission to publication: weeks

Publication charges

  • Article Processing Charges (APCs): No
  • Submission charges: No
  • Waiver policy for charges? No

Open access & licensing

  • Type of License: CC BY
  • License terms
  • Open Access Statement: No
  • Year open access content began: 2001
  • Does the author retain unrestricted copyright? False
  • Does the author retain publishing rights? False

Best practice polices

  • Permanent article identifier: DOI
  • Content digitally archived in: eLIBRARY.RU
  • Deposit policy registered in:

This journal has '56' articles

Vegetation Fire Behavior Prediction

Vegetation Fire Behavior Prediction

Authors: A.V. Volokitina, T.M. Sofronova, M.A. Korets
Year: 2020, Volume: 17, Number: 1
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Abstract

The necessity for predicting the behavior of vegetation fires, including forest fires, is keenly felt in a time of severe droughts, which periodically recur in this or that area, and their precise prediction is still hampered. It is unfeasible to maintain sufficient forces and means in each region for suppressing all emerging fires. Merely the increase of technical power won’t solve the problem, as evidenced by the experience of developed countries, where much attention, along with fire danger rating, has long been given to the development of a fire behavior prediction system. Such system in Russia isn’t available yet, and the use of international practices seems to be impossible, since it is complicated by several factors and, above all, different historically developed approaches to the pyrological classification of vegetation and its inventory. Currently, there are all opportunities for creating the Russian system for vegetation fire behavior prediction (including forest fires): fundamental pyrological developments based on the research results of the nature of fires; a fire monitoring system has been created and is being developed; and fire danger (both natural and due to the weather conditions) rating is being improved. The article presents a principle diagram of the vegetation fire behavior prediction and considers its main components. A practical model was chosen for prediction the burning spread rate. The necessary data base for the model is available in the GIS system. Software for creation vegetation fuel (VF) maps and prediction the behavior of surface forest fires, which are up to 97 % of all occurring fires has been developed, retrospectively verified and registered. Examples of the VF maps for the Chunskoye Forest District (Krasnoyarsk Krai) for different periods of the fire season are given. They are created based on the use of forest management information and a type identifier of primary fire carriers (i.e. the first VF group), which is directly shown in the maps. Information on the other groups of VF supporting, delaying burning or not participating in the process of burning spread, is attached to the map in the form of a pyrological description. A list of the data included in the pyrological description is given, as well as the reasons, which hold back on practical application of pyrological developments available in Russia for predicting the behavior of vegetation fires into the forest fire protection service.

Keywords: vegetation fire, fire behavior, model of burning spread, information data base, program of surface fire spread prediction
A Variety or a Separate Species?

A Variety or a Separate Species?

Authors: L.V. Vetchinnikova, A.F. Titov
Year: 2020, Volume: 23, Number: 1
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Abstract

Curly (Karelian) birch is a unique and highly valuable representative of woody flora, whose natural growth has been preserved only in the north-west of continental Europe. The article recapitulates the development of views on the taxonomic status and systematic position of the birch. We have analyzed the numerous facts and observations, which, from our perspective, bear record to correspondence of curly birch to the species taxonomic rank. It was done based on our own and published data, and in accordance with generally accepted criteria of the species (morphological, biochemical, genetic, reproductive, geographical, and ecological). The issues of separateness and relatedness of the birch to other representatives of the genus Betula L. are considered. It is emphasized that the recognition of curly birch as a separate biological species is important not only for scientific reasons, but also has great environmental significance since international and national nature protection documents, regulations and laws are focused on animals and plants with a species status.

Keywords: curly birch Betula pendula Roth var. carelica (Mercklin) Hämet-Ahti, taxonomic status, species criteria, Republic of Karelia
Selection of Resistant Species of Rosa L. for the Purposes of Forest Reclamation, Landscaping and Use in Biotechnology (On the Example of Volgograd Region)

Selection of Resistant Species of Rosa L. for the Purposes of Forest Reclamation, Landscaping and Use in Biotechnology (On the Example of Volgograd Region)

Authors: A.S. Solomentseva, N.I. Lebed’, S.V. Kolmukidi, A.S. Mezhevova
Year: 2020, Volume: 14, Number: 1
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Abstract

Selection of sustainable and ornamental rosehip species is relevant for their widespread use in forest reclamation and landscaping of settlements in the arid region. The objects of research were rosehips with different areas of natural expansion: R. rugosa, including form alba War Rehder, R. cinnamomea, R. beggeriana, R. acicularis, R. spinosissima, R. canina growing at points of introduction on different soils. In 2018, June was the hottest month, while February was the coldest month in Volgograd region. The maximum deviation from the average monthly temperature was observed in March. July and January were the hottest and the coldest months, respectively, in Samara region. During the research period, the species of wild roses retained the life form of habitus, and their height varied from 1.0–2.0 m (medium-grown species) to 0.7–0.9 m (short species). Data on the resistance of rosehip species to the maximum and minimum temperatures can be the factual basis of systemarealogical forecasting for geographical points of introduction. The degree of demand of rosehips to soil fertility and light was revealed by poor-demanding species: R. beggeriana, R. cinnamomea, R. rugosa and R. spinosissima. The observing method of the Main Botanical garden, field and laboratory observations allowed to establish the duration of the phenological phases of the studied species. Rosehips, being ornamental throughout the growing season, are useful in forest reclamation and landscaping, depending on the growth and color of their flowers. Types of diseases and parasitic fungi were determined by mycological analysis and reference data. The most common disease of the studied species of rosehips is powdery mildew from the genus Sphaerotheca. Amino acid profile of rosehip fruits was determined by the capillary electrophoresis system “Kapel” at a wavelength of 250 nm and allowed to identify the most valuable by biochemical composition species. In the period of monitoring the winter hardiness of rosehips, the best result was shown by the species R. rugosa, R. cinnamomea and R. canina, belonging to the North American, European and Far Eastern collections. The method of a priori ranking of fruiting indicators based on the division of factors in the descending order of their contribution revealed the most promising species for use in bio technology. The total sum of ranks and the sum of squares of deviations were determined; the concordance coefficient and the degree of consistency of the researchers’ opinions are obtained in accordance with the degrees-of-freedom breakdown. It was found that the use of biotechnological methods in modern seed production is the most pressing; the obtained results will contribute to the improvement and acceleration of the seed production process in the arid conditions of Volgograd region. Recommendations are given for the cultivation of rosehips depending on the natural and climatic conditions of the different districts of the region.

Keywords: Rosa L., growth, development, biotechnologies, green construction, a priori ranking, phytopathogens
Growth Dynamics and Status Assessment of Scots Pine Crops on Reedgrass Meadow Cuts by Remote Sensing Techniques

Growth Dynamics and Status Assessment of Scots Pine Crops on Reedgrass Meadow Cuts by Remote Sensing Techniques

Authors: O.I. Gavrilova, I.V. Morozova, Yu.V. Olkhin, A.L. Yureva, A.O. Ioffe
Year: 2020, Volume: 12, Number: 1
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Abstract

Well-timed and high-quality artificial reforestation is one of the main factors of sustainable forest management. Efficient forest stand formation is influenced by the right choice of the reforestation method and efficient planting material species. Longstanding research of pine crops’ growth in the taiga zone of the Republic of Karelia was held according to the conventional methods. In order to confirm the objectivity of the obtained research results multitime materials of remote sensing taken from the satellites of Landsat and Sentinel series were used for the first time. The presence of red and near infrared channels in the received data allows to calculate NDVI (Normalized Difference Vegetation Index), which gives the opportunity to estimate the photosynthetic active biomass. The index is the difference between the reflected intensities in infrared and red channels divided by the sum of its intensities. The use of NDVI for the study of reforestation dynamics is of reserach interest. Forest live cover analysis has shown that the quota of cereals and fireweed has essentially decreased, while the quota of forest species has increased. It was found that the coniferous stand of the I and Ia quality classes with the stock not fewer than 29.2 m3/ha has developed after Scots pine crops’ formation on the cultivated land of reedgrass meadow cuts by 2019.

Keywords: forest crops, Scots pine, planting material, remote sensing, photosynthetically active biomass, phytomass, vegetation index, cut
Understory Vegetation Cover Components Assessment in Anthropogenically Disturbed Birch Stands of Krasnoyarsk Forest-Steppe

Understory Vegetation Cover Components Assessment in Anthropogenically Disturbed Birch Stands of Krasnoyarsk Forest-Steppe

Authors: I.A. Goncharova, L.N. Skripal’shchikova, A.P. Barchenkov, A.S. Shushpanov
Year: 2020, Volume: 13, Number: 1
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Abstract

The vegetation cover characteristics of anthropogenically disturbed birch stands of Krasnoyarsk forest-steppe are studied. The research purpose is to study the current state of under story vegetation cover of the birch stands, which have been exposed to recreational and anthropogenic impacts for a long time, as well as to assess the degree and nature of its change over the 12-year period since the last research. The studies were carried out on the sample plots laid out in mixed herbs birch stands. Cenosises are characterized by V–VI age classes, II–IV quality classes, and 0.6–0.9 density of stocking. The birch stands are located in the main transfer of Krasnoyarsk industrial emissions. Phytocenoses were under significant anthropogenic and recreational impact for a long time. At each facility, 30 sites (1 m2 each) were laid, where species composition, horizontal and vertical structure, projective cover and occurrence of undergrowth and forest live cover species were assessed. The comparative analysis of floristic lists was performed using the Sørensen-Czekanowski coefficient (Ksc). The degree of species diversity was estimated by using the Shannon index; the degree of recreational transformation – synanthropization index. Cuttings were taken from 10 sites (20 × 25 cm each) for recording the phytomass stock of forest live cover on each sample area. Plants were cut off at the litter level, sorted by species, dried and weighed. Rating scales of digression were used to study the recreation influence. The degree of anthropogenic impact was determined by the content of toxic ingredients in plants of living ground cover. It is found that the toxic elements concentration in plants does not reach excessive values at which homeostasis disturbance happens. It was concluded that the changes in vegetation cover observed in 2017 in relation to the state of 2005 are more due to recreational than anthropogenic impact; which changed due to the introduction of a new technology at the JSC “RUSAL Krasnoyarsk Aluminum Plant”, which made it possible to reduce toxic industrial emissions. According to the study results, the species composition of the undergrowth and forest live cover was determined, the features of its change over a 12-year period were revealed. It is noted that species diversity has decreased and the proportion of synanthropic species has increased across all plots. Total forest live cover phytomass and individual species phytomass are determined at each plot. The regularities of change in different species contribution to the total stock of phytomass, depending on recreational impact changes, were identified. The ground cover recreational digression stages are determined by analyzing the changes in species diversity, the quantitative ratio of ecological-cenotic groups, the structure and the absolute value of phytomass.

Keywords: Krasnoyarsk forest-steppe, birch stands, ground layer, species composition, anthropogenic factors, phytomass stock
Changes in Density and Species Composition of Undergrowth at Different Distances from the Forest Edges in Postagrogenic Areas

Changes in Density and Species Composition of Undergrowth at Different Distances from the Forest Edges in Postagrogenic Areas

Authors: P.A. Feklistov, M.V. Averina, I.N. Bolotov, B.Yu. Filippov, D.N. Klevtsov
Year: 2020, Volume: 11, Number: 1
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Abstract

The work is devoted to the study of changes in density and species diversity of undergrowth at different distances from the forest edges on postagrogenic lands, as well as factors affecting the distribution of undergrowth by area. The studies were done in the middle subzone of taiga in the Velsk district of Arkhangelsk region. Undergrowth was studied on tapes laid out parallel to the forest edges and at different distances from them with 10-meter intervals. Enumerations were carried out by breed, height class and living state. The type of use, the period of non-use as intended, the degree of grassing down and the particle-size composition of soil were determined for all postagrogenic areas. The most important deriver affecting the process of overgrowth and range of propagation of undergrowth is the period of non-use of this area for the intended purpose (correlation coefficient is 0.94) and the degree of grassing down (correlation coefficient is 0.54). The more time has passed since the termination of agricultural activity, the higher the quantity of undergrowth and the further it spreads from the forest edges. At 10 years of non-use, the undergrowth occurs up to a distance of 50 m, and already at 20–25 years it appears at a distance of 90 m from the forest edge. The range of propagation of undergrowth from the forest edge is not affected by such characteristics of the field as the type of use and the particle-size composition of soil. The total density of undergrowth decreases at a distance from the forest edge from 10,000 (0–30 m) to 1,600 (80–90 m) pcs/ha. These figures for the economically valuable species, such as spruce and pine, are from 7,533 (10 m from the forest edge) to 800 (90 m from the forest edge) pcs/ha and from 2,533 to 400 pcs/ha, respectively. The species spectrum of undergrowth corresponds to the woody vegetation composition within the forest edges adjacent to the fields and includes pine, spruce, birch, alder, and aspen. Aspen disappears from the species composition with a distance of 30 m from the forest edge. The species ratio in the undergrowth composition varies, however the dominant species are spruce and pine at different distances from the forest edges.

Keywords: undergrowth, tree species, density of undergrowth, height of undergrowth, postagrogenic lands
Growth and Productivity of Pine Forest Crops Named after S.V. Alekseev in the European North of Russia

Growth and Productivity of Pine Forest Crops Named after S.V. Alekseev in the European North of Russia

Authors: D.N. Soldatova, A.S. Ilintsev
Year: 2020, Volume: 14, Number: 1
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Abstract

Sowing and planting of forests in the European North are the most important silvicultural treatment that guarantee the regeneration of coniferous species in present-day conditions. Lack of relevant information on the historical experience of forest crop development and current state of such objects is an indicator of a certain information vacuum. The research purpose was to assess growth and productivity of experimental forest crops of pine of the northern arborist S.V. Alekseev developed by the sowing method in 1927–1930 and to compare them with natural stands. The research was carried out at the stationary site “Experimental Forest Crops of Pine named after S.V. Alekseev”, which is located in the central part of Arkhangelsk region. The oldest experimental forest crops in the European North of Russia grow on the site. S.V. Alekseev used different forest crops in order to choose rational ways of their development. We examined forest crops at 4 permanent sample plots in 2018. Collection, processing and analysis of field data was carried out according to the methods generally accepted in forest inventory. The following parameters were determined: average diameter and height, relative and absolute density, quality class, standing volume, stand composition, mean increment, and current mean periodic increment. The dynamics of inventory parameters of forest crops for the period from 1999 to 2018 shows that all forest elements are in a phase of active growth. Over the 19-year period, the share of pine in the stand decreased by 3–10 %, while the share of spruce and birch increased by 3–7 % and by 2–3 %, respectively. Herewith the number of trees of all species decreased by 3–36 % and amounted to 1420–1952 pcs/ha in forest crops. The total cross-sectional area increased by 3.6–11.6 m2/ha. The standing volume increased by 88–133 m3/ha. The current mean periodic increment of forest crops ranged from 4.6 to 7.0 m3/ha. Analysis of the inventory parameters of the studied stands shows that forest crops are not inferior in growth to normal pine stands of Arkhangelsk region. The total density of forest crops exceeds the density of normal pine stands by 29.4–125.7 %. The total standing volume of forest crops have reached high levels by the age of 90. The total standing volume of forest crops is 416–444 m3/ha, including pine (284–342 m3/ha). The mean increment of forest crops is 4.6–5.0 m3/ha, including pine (3.2–3.8 m3/ha). Forest crops growing on the 3rd sample plot (option 8) are the best option among those examined by productivity according to the complex of inventory parameters (density, standing volume, increment, pine share in the composition). The experiments of S.V. Alekseev show that the sowing method can provide guaranteed reforestation of pine in the European North.

Keywords: forest crops, Scots pine, sowing method, increment, productivity, standing volume, natural monument of regional significance
Quantitative Characteristics of Local Strain Fields in a Top-Liner Board Sample under Uniaxial Tension

Quantitative Characteristics of Local Strain Fields in a Top-Liner Board Sample under Uniaxial Tension

Authors: A.N. Romanova, Ya.V. Kazakov, A.V. Malkov
Year: 2020, Volume: 10, Number: 1
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Abstract

The paper presents the method for quantifying the distribution of local tensile (longitudinal), compressive (transverse) and shear strains in a sample of pulp and paper material. The results of its use for the sample of top-liner board when uniaxial tensile testing are provided. Applying this method, we have determined the values, the degree of heterogeneity and change patterns of local strains in inhomogeneous and anisotropic structure of the sample, depending on the total strain and the direction of fiber orientation. The method is based on constant-speed tensile testing of samples with a pre-applied dot matrix to their surface. The test is accompanied with photo fixing and recording a load-elongation curve. The coordinates and displacements of dots are determined by means of the specially designed software. The analysis of data and calculation of local deformations are performed by finite elements method (FEM) algorithms. The outcomes have shown that the local longitudinal deformations increased, transverse – decreased, and shear – had their maximum at 45° to machine direction (MD) when increasing the angle of preferential fiber orientation to MD in the board samples. The rise of the average absolute values of all components of local strains when increasing total deformation in the sample was confirmed. As it has been found, the heterogeneity of local strains, estimated through the standard deviation, rose when increasing their absolute value; the trends of changing depend on the fiber orientation direction in the sample structure.

Keywords: top-liner board, structural inhomogeneity, anisotropy, deformations, FEM
Thermal Conductivity of Wood-Based Cellular Structures

Thermal Conductivity of Wood-Based Cellular Structures

Authors: A.A. Lukash, N.P. Lukutsova
Year: 2020, Volume: 10, Number: 1
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Abstract

A physical model is developed for heating a set of laminated cellular structure formed from peeled veneer, dependences for determining its thermal conductivity under conditions of non-stationary heat transfer are proposed. It was found that for a package of 11 layers of birch veneer 2 mm thick, the thermal diffusivity is 1.93∙10–6 m2/s. Based on the fundamental theory of thermal conductivity of the wood substance, dependencies are obtained for calculating the duration of bonding of heat-insulating materials of a cellular structure. It has been established that the duration of gluing of a 22 mm thick plywood mesh slab of peeled birch veneer under pressure exposure is 14.5 minutes at a temperature of press plates 110 °C. The thermotechnical characteristics of the new wood-based cellular structure material were determined: the thermal conductivity coefficient of a cellular plywood board with a density of 530 kg/m3 was 0.081 W/(m·K), the strength under static bending of the board parallel to the fibers of the outer layers was 14 MPa, and perpendicular to the fibers was 10 MPa. The use of underutilized soft broadleaved species with low operational properties as a heat-insulating material, where high strength indicators are not required, is justified, since its thermal conductivity is two times lower than that of a similar material – solid plywood board.

Keywords: plywood cellular board, hardwood, thermal conductivity, veneer, gluing, heat exchange
Modeling the Process of Sawn Timber Drying

Modeling the Process of Sawn Timber Drying

Authors: A.G. Gorokhovsky, V.V. Pobedinsky, E.E. Shishkina, E.V. Pobedinskiy
Year: 2020, Volume: 13, Number: 1
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Abstract

The article considers the problem of sawn timber drying. The relevance of research is driven by the need to improve the automated process control system for drying sawn timber on the basis of modern information technologies, as well as to reduce the energy intensity of these technologies, which is enshrined in the program documents of forest industry development at the government level. The functional purpose of the automated control system is to provide a set level of the wood moisture content with the required quality of wood (zero ruptures). It is of immense complexity to obtain such functional dependency on the heating temperature in the chamber and the equilibrium air humidity by traditional statistical methods due to the uncertainty conditions of parameters, therefore, the apparatus of the fuzzy set theory should be used. Thus, the research purpose included generation of functional dependences of the sawn timber moisture content and drying time on the heating temperature and the equilibrium air humidity in the drying chamber based on fuzzy inference. The methodological basis of the theoretical studies was as follows: the theory of drying; the provisions of mathematical and fuzzy modeling; and, in terms of checking the adequacy of the proposed fuzzy model, the methods of mathematical statistics and experimental theory. The research results are the obtained dependences of the moisture content of sawn timber and drying time on the heating temperature and the equilibrium air humidity in the drying chamber, the synthesis of which is performed by means of Fuzzy Logic Toolbox of MATLAB application. The proposed functions of the moisture content and sawn timber drying time take into account the basic process configurations (the heating temperature and the equilibrium air humidity) and are experimentally verified for adequacy. The practical applicability of the results lies in the possibility of creating an intelligent system of automatic control of the sawn timber drying process.

Keywords: wood drying, wood moisture content, equilibrium air humidity, fuzzy modeling, fuzzy inference
Combustion Efficiency of Wood Fuel in the Water Boilers KVU-2000

Combustion Efficiency of Wood Fuel in the Water Boilers KVU-2000

Authors: V.K. Lyubov, A.N. Popov
Year: 2020, Volume: 13, Number: 1
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Abstract

Renewable energy use is one of priority areas of power production development. One of the sources is wood biomass. Utilization of wood biomass in the regions with developed timber industry is a prospective decision in ensuring power independence. Wood biomass usage allows to recover by-products of logging and woodworking industries, generate cheaper electric power and reduce an impact on the environment. The North-West of Russia has huge wood reserves. As a result, the issues of efficient utilization of wood biomass are relevant for the region. An effective way of the complex solution of energetical and ecological problems with provision of heating loads is application of modern devices operating on wood fuel such as modern water boilers. This study aims to analyze heat engineering and environmental performance of the boiler KVU-2000 during the combustion of by-products of timber industry. The components of the boiler’s heat balance and gaseous effluents have been determined. Emissions of particulate matter and the content of soot particles have been studied. The study results have shown that the boiler KVU-2000 provides high economic and environmental performance when operating on polydisperse wood fuel. However, a manual regulation of secondary air flow and absence of the flue gas oxygen control systems do not allow to keep optimum combustion air-blown mode. Absence of resistance control devices for ash collectors and thermal insulation of elements in post-combustion gas path lead to irrational heat losses, which conflicts with normative regulations. A limited operational period between cleaning of heating surfaces of a fire-tube boiler demands strict requirements to capacity redundancy. Elimination of identified flaws will ensure substantial increase of energetic and economic performance of the boilers; allow to minimize the emissions of harmful substances of biofuel burning, and recommend these boilers for application in heat supply systems in the Arctic region.

Keywords: water boiler, wood fuel, harmful substances, furnace, heat losses, efficiency
Operating Efficiency Improvement of Machinery and Equipment while Logging in Forests with Radioactive Contamination

Operating Efficiency Improvement of Machinery and Equipment while Logging in Forests with Radioactive Contamination

Authors: A.N. Zaikin, A.S. Toropov, B.M. Merkelov, V.V. Sivakov
Year: 2020, Volume: 15, Number: 1
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Abstract

Due to technogenic accidents at nuclear power plants, including the Chernobyl Nuclear Power Plant, part of the forests of the Russian Federation was exposed to radioactive contamination. As a result, it established the conditions under which multipurpose use of forests and forest resources is impossible over the long run. These forests pose a serious environmental hazard due to the possibility of transfer of radioactive contamination to clean areas, because of the occurrence of antropogenic and natural fires. Logging and use of wood from such regions is an urgent issue, which provides environmental problem solving by reducing the possibility of recontamination with radionuclides of surroundings. One of the solutions within the given senario is our proposed technology for the integrated processing of wood contaminated with radionuclides based on internally powered mobile packages of machinery and equipment operating directly on the cutting area or self-propelled vehicles in order to produce clear timber. Herewith, the arisen need to minimize the operating time of machines and equipment is capable of being achieved through the coordinated functioning of cutting machines with mobile equipment in terms of the volume of processed wood at each stage. Coordination of the production volumes of machines and equipment is possible through the creation and maintenance (consumption, replenishment and production) at a specific level of day-on-hand stocks for particular conditions. The operating modes of a set of machines as a whole are determined taking into account previously developed models, providing for an increase in the number and/or shift of machines and equipment functioning in logging operations. This problem solving approach will allow: to ensure the volume of production of a set of machines and equipment equal to the production volume of the leading equipment of the set; reduce the number of days required to harvest a given amount of wood; reduce the amount of pollutants (for example, carbon monoxide) that selfpropelled engines emit into the atmosphere.

Keywords: radionuclides, contamination, longitudinal cutting, recycling, cutting area, set of machines, stem, sawn timber
Substantiation of the Technology of Mechanized Clear-Cutting of Reservoir Beds and Equipment Arrangement for Its Implementation

Substantiation of the Technology of Mechanized Clear-Cutting of Reservoir Beds and Equipment Arrangement for Its Implementation

Authors: S.N. Orlovsky
Year: 2020, Volume: 18, Number: 1
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Abstract

The issue of cleaning reservoir beds during the construction of cascades of hydroelectric power plants is relevant. In current practice, forest clearance is carried out in the form of clear-cutting 15–20 years before the flooding of the area. Herewith, the fact that even before flooding, the reservoir bed is secondly overgrown with fine-sized deciduous species with trunk diameter of up to 15 cm, average volume per tree of which is 3–5 times less than that of previous stands, is ignored. In view of this, it turned out that the use of existing harvesting and logging equipment is ineffective in this type of works. It is necessary to develop machines and technologies that ensure the fulfillment of the assigned task. The research purpose is to develop a technology for cleaning the reservoir bed (on the example of the Boguchany Hydro Power Plant (HPP) on the Angara river) from secondary overgrowing after clear-cutting; as well as the design and arrangement of equipment for the fellerbuncher LP-19V for trees cutting, and the technology of its application. The research agenda includes an analysis of wood cutting forces with regard to inertial forces; calculations of the productivity of the unit for cutting stands and their transportation to the place of loading; sizing of forest swathes, their number and skidding or haulage distances; study of use modes of equipment for cutting stumps, forest clearance and hauling. A design of the working body for the feller-buncher LP-19V is proposed, including a disk cutter and a packer, which allows to increase its productivity in cutting areas by 3–4 times with a whip volume of about 0.14 m3. A technology for loading and delivering timber to barges, and processing unmerchantable wood has been developed. The proposed technology for recleaning the reservoir bed of a hydro power plant allows to fully mechanize the technological process of forest clearance, reduce labour costs and improve the cleaning quality, reduce the negative effects associated with flooding of tree stands while filling HHP reservoirs.

Keywords: reservoir, forest clearance, technology, mechanization, cutting of stands, arrangement, design
Study of Modified Wood by Electron Microscopy

Study of Modified Wood by Electron Microscopy

Authors: V.A. Shamaev
Year: 2020, Volume: 10, Number: 1
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Abstract

Wood modification is a popular method for improvement of wood properties of low-value deciduous species. The method of pressing across the wood fibers preliminarily plasticized with urea was used in order to increase the strength properties. Impregnation with Biol mineral oil was used for the improvement of anti-friction properties. Metallic nickel is introduced into wood in the form of a continuous metal film lining the inner surface of wood cavities for thermal conductivity increasing. Studies carried out with the listed catalog samples using scanning and upright electron microscopes allowed to find, that: carbamide is located in the walls of cells and manifests itself in the cavities very sharply in the form of single crystals; pressing of wood plasticized with urea leads to flattening of anatomical elements without their destruction; Biol oiling with its low content spreads as a film on the cell walls and is not visualized; metallic nickel is present in wood in the form of film and individual elements on the cell walls. Weight and atomic microanalyses of the longitudinal section were performed for it.

Keywords: wood, microstructure, modification, electron microscopy
Elastic and Relaxation Properties of Larch Wood and Their Role in Production of Wood and Charcoal Briquettes

Elastic and Relaxation Properties of Larch Wood and Their Role in Production of Wood and Charcoal Briquettes

Authors: A.A. Pekarets, O.A. Erokhina, V.V. Novozhilov, Yu.G. Mandre, E.L. Akim
Year: 2020, Volume: 9, Number: 1
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Abstract

Processing of sawdust, which accounts for 10…12 % of the volume of processed raw wood materials in products with high added value, is one of the areas of woodbiorefining. This became a premise for sawdust processing into secondgeneration biofuel, as well as carbonized briquettes based on it. The relaxation properties of larch wood are studied and their role in the technological process carried out in creation of new generation biofuel with a given set of operational properties is analyzedtaking into account the specific features of relaxation transitions at the stages of obtaining wood and charcoal briquettes.The relationship between the directed change in the relaxation state of the wood polymer components (lignin, cellulose and hemicelluloses) and the operational parameters is considered. The experimental data findings confirm that cellulose and hemicelluloses are in a high-elastic state in the initial wood and sawdust.It is advisable to ensure that the wood polymer components are transferred below the brittle temperature, in other words, wood should be dried to the lowest possible residual moisture, in order to grind wood sawdust to a powdery state with minimum energy consumption. Subsequent steam humidification to a moisture content of 3…4 % gives the system extrusion ability due to the formation of hemicellulose gel layers on the surface.

Keywords: wood biorefining, larch wood, biofuel, wood briquettes, charcoalbriquettes, pellets, physical and mechanical properties, relaxation properties

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