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 '88' articles

Formation of a Digital Elevation Model of Soil Moisture Adopted from Terrain Parameters and Forest Management Materials

Formation of a Digital Elevation Model of Soil Moisture Adopted from Terrain Parameters and Forest Management Materials

Authors: S.K. Farber, N.S. Kuzmik
Year: 2020, Volume: 15, Number: 4
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Abstract

The visibility of the spatial distribution of soil moisture is achieved through mapping, which is most simply carried out according to a digital model. Information on soil moisture is stored in the attribute table field of the Geographic Information System (GIS) layer and available for editing and later use. It is shown that a digital moisture model can be obtained through the cross-spectrum analysis of soil moisture with terrain parameters (frame of mapping – a digital elevation model) and ranking of forest types in order of increasing soil moisture (frame of mapping – a feature layer of inventory plots). The mapping results are demonstrated in terms of 2 test sites in mountainous and flat areas. Soil moisture mapping based on the DEM (digital elevation model) data was performed for a test site located in the Axial Western Sayan district of the mountain taiga forests; where forest types, due to the spatial cross-spectrum analysis, are distributed by terrain parameters and ranked by soil moisture. The result of the spatial analysis of the DEM is a raster (digital elevation model of soil moisture). Soil moisture mapping based on the forest management materials is performed for the test area representing the southern taiga forests of the Angara region. Ranking of soil moisture is made on the basis of inventory plot descriptions of the test site. The data of inventory plots was excluded from the analysis. Growth of tree species is a priori impossible down there (wetlands, rivers and lakes). In a simplified form, a ranked range of soil moisture is also demonstrated relative to the forest type as a generalized qualitative indicator of forest site conditions. Regardless of the land category (plantation, burnt area or cutover), each inventory plot receives an additional quantitative indicator of soil moisture, followed by the possibility of determining the regression equations for the potential productivity of tree species. It is found that in the presence of a feature layer of forest management data, soil moisture mapping is preferable to be adapted from the forest management materials. It is shown that there is a dependence of the productivity of stands on soil moisture.

Keywords: soil moisture, terrain, forest type, quality class, potential productivity of forest stands, mapping of soil moisture
Wood Microstructure of Pine Plantations with Different Initial Stocking Rate on Drained Peat Soil upon Fertilization and Herbicide Treatments

Wood Microstructure of Pine Plantations with Different Initial Stocking Rate on Drained Peat Soil upon Fertilization and Herbicide Treatments

Authors: Ya.A. Neronova
Year: 2020, Volume: 9, Number: 4
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Abstract

To secure a steady operation of large wood processing enterprises in north-west of the Taiga zone, accelerated coniferous forest cultivation appears to be the most promising. Treatments with mineral fertilizers and herbicides create optimal conditions for stand growth and thus result in wood increment. Trunk wood qualities and, hence, the output of the most valuable trunk sections are contingent on the volume and anatomical structure of radial increment. This paper shows the effect of fertilization and herbicide treatments on the anatomical structure of wood in pine plantations of different stocking rates in drained peat soils. Variations of late wood share and density are directly associated with the changes in anatomical structure of wood. Fertilization of pine plantations with density of 4000 and 2000 trees/ha increased the number of early tracheid rows in the process of their growth. The application of fertilizers and herbicides in pine plantations stocked at 1000 trees/ha induced a gradual reduction in the number of early tracheid rows. A combined mineral fertilizer plus herbicide treatment enlarged the number of late tracheid rows in wood of the plantations stocked at various rates. The total number of tracheid rows per annual ring increased in the plantations stocked at a rate of 4000 and 2000 trees/ha. The reduction in total number of tracheid rows of plantations with 1000 trees/ha stocking rate is down to mineral fertilization combined with herbicide treatments. Fertilizer and herbicide treatment of the plantations with the initial density of 4000 trees/ha leads to the formation of thick-walled early and late tracheids. Application of fertilizers in pine plantations with 1000 and 2000 trees/ha stocking rates promote the formation of early and late tracheids of a larger diameter. Tracheids of a smaller diameter were formed in the plantations stocked at 4000 trees/ha. The overall impact of fertilizers and herbicides caused an increase of late tracheid size in the plantations with different stocking rates. Comparing the obtained data with the regulatory requirements of GOST 968–68 and the Laboratory of Raw Materials of the All-Union Scientific Research Institute of Pulp and Paper Industry, we have found that cultivation of pine plantations with various stocking rates on dried peat soils using fertilizers and herbicides can be aimed at producing pulpwood (1st and 2nd categories) and high-quality sawlogs.

Keywords: pine plantations, wood microstructure, fertilizers, herbicides, number of tracheid rows, tracheid wall thickness, tracheid lumen diameter
Transport, Distribution and Consumption of Pine and Spruce 14C-Assimilates in Northern Phytocenoses under Different Illumination and Nitrogen Nutrition

Transport, Distribution and Consumption of Pine and Spruce 14C-Assimilates in Northern Phytocenoses under Different Illumination and Nitrogen Nutrition

Authors: V.N. Konovalov, L.V. Zarubina
Year: 2020, Volume: 18, Number: 4
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Abstract

A rational system of cuttings, mineral nutrition of plants, and preservation of softwood undergrowth during felling is one of the ways to increase the productivity of boreal forests. The physiological methods of research used in forestry and, first of all, the study of donoracceptor interactions, allow obtaining the necessary information on the efficiency level of forestry measures in the stands of pine and spruce undergrowth quickly enough (within 1–2 years) without waiting for the final result in the form of an increment in shoots. The dynam ics of accumulation, transportation and distribution of 14C in organs and tissues of a tree under the influence of selective cuttings and a nitrogen dose has been studied in spruce and pine undergrowth in stands of different species composition and age. The study objects have been: blueberry spruce and birch forests of the forest site types with varying intensity of cutting; lichen pine forests formed from pine undergrowth preserved during the cutting. It were found that, in the summer period under the canopy of spruce and birch forests, the illumination does not exceed 8–10 % of the open area and does not correspond to the biological norm for spruce. The lack of solar radiation and soil nitrogen in the undergrowth of these tree species leads to a decrease in the intensity of photosynthesis and the violation of donoracceptor bonds, delays evacuation of assimilates from a leaf and their transportation to the active zones, suppresses the growth activity and the associated with it “demand” for macronutrients sent to the leaves declines the vitality of plants. The efficiency of the root system deteriorates, the formation of a new assimilation apparatus is delayed, and the growth processes of vegetative organs are violated due to the lack production of assimilates and the disruption of their distribution system. Nitrogen introduced into the stands and selective cuttings in pine and spruce undergrowth activate the synthetic and absorption activity of the root system, improve the functioning of the assimilation apparatus, strengthen the donoracceptor interactions between the aboveground and underground organs of a tree, significantly accelerate the outflow of photosynthetic products from a leaf, and positively influence on the growth processes. It has been found that, according to the level of activity of the donor-acceptor system for the pine and spruce undergrowth, it is possible within 1–2 years to set up a system of felling and a dose of nitrogen introduced into the forest stands that most closely meet the needs of these species.

Keywords: pine undergrowth, spruce undergrowth, illumination, lichen pine forest, blueberry spruce forest, blueberry birch forest, donor-acceptor interactions, selective cutting, nitrogen fertilizers
Changes in the Physical Properties of Segregational Chernozems in Agroforest Landscapes of the Central Chernozem Region

Changes in the Physical Properties of Segregational Chernozems in Agroforest Landscapes of the Central Chernozem Region

Authors: V.I. Turusov, Yu.I. Cheverdin, V.A. Bespalov, T.V. Titova
Year: 2020, Volume: 18, Number: 4
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Abstract

The basic physical properties of chernozems in agroforest landscapes of the Central Chernozem region are studied within the framework of the program by the topic of the state assignment for 2018–2020. The studies carried out in the conditions of agrocenoses and undisturbed ecosystems were divided by the effect of agrogenic and agroforestal nature. Agrogenic effect was considered through a case study of the fallow lands put in operation in tillage. While agroforestal effect was considered through a case study of the influence of forest belts on soil cover. It is found that rearrangement of soil aggregates number takes place under the influence of forest belts and at introduction of fallow lands to agricultural use, but in different scenarios. The soil blocky fraction (less than 10 mm) in the arable horizon increases by 6–14 times under the agrogenic effect in comparison with the fallow. Contrary to this, the share of silt fraction (less than 0.25 mm) on the arable land decreases by 2–4 times and the structure coefficient decreases by 8–13 times. The minimum content of agronomically valuable aggregates (sum of 0.25–10 mm) is registered for the arable land soils compared to the fellow and forest belt for all selected layers. The average amount of aggregates lies in the range of 58–73 % for the arable lands, whereas the share of aggregates in the size of 0.25–10 mm is in the range of 85–95 % for the forest belt and fallow. A content reduction in the fractions of the following sizes 0.25–0.5; 0.5–1; 1–2; 2–3 and 3–5 mm influenced on a decrease in the agronomically valuable structure of the arable land in comparison with the fallow. The agroforestal effect on the structural composition of soil cover is more gently. The share of soil blocky fraction increases slightly. The sum of the agronomically valuable aggregates in the soil of the forest belt in depth of 10–20 and 20–40 cm corresponds the chernozem level of the fallow. Herewith, the share of the silt fraction in the soils of the natural cenoses is higher. And as a consequence of this, the values of the structural soil coefficient of the forest belt chernozem insignificantly exceed similar values in the fallow soils at the same depths. Statistical features of distribution of the basic aggregates in the soils subjected to intensive agrogenic and agroforestal influence are established in comparison with the fallow lands. Some statistical characteristics of distribution of the basic structural separates of the chernozem soils are calculated. The indicators of bulk density at various depths of the study sites are defined. They increase in the row of fallow – forest belt – arable land.

Keywords: forest belts, fallows, chernozem, structural composition of soils, bulk density
Variability Properties of Pinus sylvestris L. Wood in Growing Stock under Technogenic Impact

Variability Properties of Pinus sylvestris L. Wood in Growing Stock under Technogenic Impact

Authors: R.V. Schekalev, А.А. Martynyuk, V.I. Melekhov
Year: 2020, Volume: 10, Number: 4
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Abstract

The issues of variability of pinewood (Pinus sylvestris L.) properties in growing stock located in the vicinity of operating industrial facilities is still relevant. The paper aims to assess the technogenic impact on the radial increment as well as the physical and mechanical properties of pinewood in the conditions of Northern Taiga. The impact of the distance from the source of emissions on variability of the radial increment and the volume and technical properties of wood were determined. Distribution maps of the conventional wood density and its compressive strength along the fibers inside the trunk were formed. It is found that with a decrease in the distance from the source of emissions, the average value of the radial increment of trees occurs. It is revealed that there is a decrease in wood density from the butt to the top, and from the pith to the sapwood. Also, it is determined that wood density increases as the distance to the source of emissions decreases. However, there were obtained no valid differences of the indicator of wood resistance to compression along the fibers at various distances from to the source of emissions.

Keywords: pine, wood, radial increment, wood density, wood compressive strength along the fibers, emission source distance
Technological Resources of Harvesting and Logging Machinery of Bashkortostan Forestries

Technological Resources of Harvesting and Logging Machinery of Bashkortostan Forestries

Authors: A.N. Zaikin, S.A. Konshakova, V.V. Sivakov, S.G. Kuznetsov, N.A. Bulkhov
Year: 2020, Volume: 11, Number: 4
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Abstract

The forest sector of the Russian economy is a complex system of industries and activities, which include logging, woodworking, furniture and pulp and paper productions. The logging organization, which forms to a great extent the operation effectiveness of any enterprise in the forest sector, is the base point for the development of any of the indicated activities. Assessment of the factors determining the efficiency of logging activities is an urgent issue of both theoretical and experimental studies, which allow identifying and specifying problems that reduce the effectiveness of logging and processing production, taking into account regional specificity. The development of competitive relations in forestry provides an opportunity to consider the essential role of forestries in the forest sector of the regions and to form the institutional framework of relations between the forest management participants relevant to the regional policy. There are two variants for the development of forestry: supporting small businesses, which operates in the forest complex, and recruitment of large investors for the forest resources development. The implementation of the national priority projects in the field of forest development is the most attractive procedure for large multiprofile wood processing enterprises with significant financial capacity and ready to develop the forest resources of the region over the long run. Modern forestries, which fulfill a function of the state institutional participant in the forest relations, carry out logging activities in the least attractive forest areas (from a competitive point of view) contributing to the welltimed and high-quality performance of the forest development plan and income to local budgets. If the state autonomous forestry organizations function in the region, then regional policy for the forest complex development should take into account the problem solving of the development of forestries through systemic modernization of their technical basis, which will allow the latter to become full members of the forest relations ensuring the effective development of the logging sector. However, a serious modernization of forestries is impossible without determining the real state of their forestry equipment. The research object is the forest sector of the Republic of Bashkortostan with the forest fund volume of 760.3 mln m3 and the established volume of annual wood harvesting of 9,156 ths m3, where 32 state autonomous forestry organizations work. In December 2017, we assessed the technical condition of the harvesting and logging equipment of the forestry institutions of the Republic of Bashkortostan in order to determine its state and opportunities for efficient use, and give the recommendations on the logging quality improvement. According to the results of the inventory of this equipment, its total number (184 units) was found, 57 % of which relate to wheeled tractors. Specialized skidding equipment is practically absent. The assessment of the wear level of the existing machinery was the important methodological component of the research. The methodology corresponding to the Federal Standard of Assessment “General Concepts of Assessment, Approaches and Requirements for the Assessment” was used for the wear assessment. The loss of the consumer value of the machines due to their wear was used as the criteria for assessing the accumulated wear of logging machinery, herewith the following estimated indicators were considered: change in the machine resource; change in production costs associated with the implementation of the resource unit during the life cycle. In the course of the research it has been found that: more than half of the Bashkortostan forestries are not provided with harvesting and logging machinery for the development of planned volumes of logging; more than 80 % of the available forestry machinery has wear of more than 90 % and its use is not economically feasible; forestries of the Republic of Bashkortostan have a weak repair facility and insufficient number of qualified personnel.

Keywords: forestries, harvesting and logging machinery, technological resources, wear, machinery condition assessment, Republic of Bashkortostan
The Influence of Larch Lumber Drying Technology on the Duration of Dehydration

The Influence of Larch Lumber Drying Technology on the Duration of Dehydration

Authors: Sh.G. Zaripov, V.A. Kornienko
Year: 2020, Volume: 13, Number: 4
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Abstract

Convective drying of lumber should be considered as a relatively simple method of elimination moisture from wood. Such technologies are widely used in bringing moisture content in lumber to a certain level. Meanwhile, this drying method is characterized by an increased duration of the process, which automatically increases the expenses for thermal and electrical energy. The drying time of larch lumber is on average higher by 1.5–2.5 times compared to other species, which further increases the cost of drying. Therefore, there is a necessity of finding ways to solve the problem of reducing the drying time of larch lumber in the conditions of convective heat exchange. One of the ways is to develop and apply such drying schedules, which would allow to accelerate the process of wood dehydration. The option of improvement the drying schedules is offered by the Finnish experts of Jartek Oy company. The developed design of the drying kiln allows to implement a two-stage structure of drying schedules: at the first stage with increasing temperature, at the second with decreasing temperature. This paper presents the results of the analysis of the operation of continuous drying kilns with zonal circulation for larch lumber drying. The analysis showed that the direction of drying agent movement along the length of the kiln during larch lumber drying is critical. This conclusion follows from the fact that larch responses in a peculiar way to temperature variations. In the initial period of drying a film of extractives is formed on the surface of the larch вoard. This film blocks the output of an aqueous solution of extractives from wood. In these circumstances, it is advisable to form such schedules that the drying agent temperature with each step of a lumber pile in the drying kiln increases. The specified principle condition for drying larch lumber is observed only in the kiln section, where counter-flow circulation is carried out. The second section, where the direct-flow circulation is implemented, practically runs idle, since the drying agent temperature with each step of the drying pile of lumber decreases. It follows that such designs of kilns for larch lumber drying is impractical for operation.

Keywords: drying technology, larch lumber, circulation, temperature, drying kiln, aqueous solution of extractives
Dimensional and Qualitative Characteristics of Round Timber Harvested in Arkhangelsk Region

Dimensional and Qualitative Characteristics of Round Timber Harvested in Arkhangelsk Region

Authors: A.A. Tambi, S.A. Ugryumov, A.R. Birman, I.A. Chernogradskaya
Year: 2020, Volume: 10, Number: 4
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Abstract

The efficiency of woodworking enterprises largely depends on the size and qualitative characteristics of round timber. The paper aims to assess the main inventory characteristics of round timber in economically accessible forest areas of Arkhangelsk region. The studies were carried out at a number of large enterprises in Arkhangelsk region using a modern VECTOR 3D photometric scanner. Measurements were made on the line for sorting logs by diameter at the warehouses of raw materials. There were examined 18,931 sawlogs. The length of each log was 6 m. The diameter range of round timber was from 10 to 42 cm. As a result of experiments, the average diameter of harvested logs of pine and spruce were found and the parameters of curvature, taper and bark content were determined depending on the top diameter of round timber. The region continues to trend a gradual decrease in the average diameter of round timber, the value of which in the considered period 2014–2018 varied in the range of 11–16 cm. Simultaneously with a decrease in the average diameter of round timber, the curvature, taper and bark content are reduced, which may indirectly indicate that wood under the age of ripeness is involved in industrial production. If in the 2000s small and medium-sized timber was harvested mainly from the tree top, today, it can be assumed that the source of such timber is young trees that have not reached the age of industrial ripeness but grow near the road infrastructure. Changes in the dimensional and qualitative characteristics of round timber are of a system nature and are makings for the modernization of the machinery and equipment used by logging enterprises and sawmills. In the context of reducing the average diameter of round timber, in order to maintain current performance and volume output of sawn timber, it is necessary to increase feed rates and introduce an optimization system resulting in provision of individual cutting of logs in accordance with their size and shape.

Keywords: round timber, average diameter, curvature, taper, timber scanning, sawlogs
Stiffness Analysis of Connections of LVL Structures with Claw Washers

Stiffness Analysis of Connections of LVL Structures with Claw Washers

Authors: A.G. Chernykh, E.V. Danilov, P.S. Koval
Year: 2020, Volume: 11, Number: 4
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Abstract

The use of claw washers in dowel connections allows to increase the bearing capacity and stiffness of joints. However, joint action of claw washers and dowels in the structures of advanced materials is studied insufficiently. The paper presents the key failures of existing methods for calculating such connections. Differential equations, that simulate the behavior of a dowel connection with claw washers taking into account the possible changes in the shape of claws, wood moisture content and the duration of loading, are presented. Washer dowel and claw are followed the equations for beams secured on a visco-elastic base, using the equation kernel K(τ,t), which reflects the nonlinearity of the factors affecting the deformation of a connection. The dowel deformation equations are given, which are proposed to be solved by the Bubnov-Galerkin method. The obtained expressions are united into a single equation using the Heaviside step functions. The deformation equations are presented as well. They are written taking into account the virtual displacement of a claw in two orthogonal directions. The expressions allow to pass from calculation of washer claws and a dowel to determination the total bearing capacity and joint stiffness. The possibility of plastification due to the changes in boundary conditions is considered for adequate simulation of connection components behavior upon reaching the plastic stage. The article provides a methodology for determining the theoretical displacements and linear stiffness of a connection. The equations are calculated using dependences available from experiments. In the course of solving the equations, it is possible to determine the values of linear stiffness. These values are compared with the experimental data received earlier to assess the adequacy of the obtained solutions. The distribution of theoretical and experimental data have an average convergence of 91 %, which confirms the validity of the presented methodology for determining the stiffness of dowel connections in LVL with claw washers. The proposed methodology can be recommended for more precise calculation of wooden structures in strength and stiffness, which will reduce their material consumption and enhence reliability.

Keywords: claw washers, LVL, wooden structures, stiffness, connections
The Use of Oxidative Alkali Treatment for Sulphate Hardwood Pulp Bleaching

The Use of Oxidative Alkali Treatment for Sulphate Hardwood Pulp Bleaching

Authors: T.A. Koroleva, L.A. Milovidova, G.V. Komarova, A.A. Dryakhlitsyn, V.V. Medvedev, V.G. Moseev
Year: 2020, Volume: 10, Number: 4
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Abstract

Pulp and paper plants use chlorine dioxide, oxygen, and hydrogen peroxide for pulp bleaching. The paper aims at analyzing the effect of oxidative alkali treatment with the addition of oxygen and hydrogen peroxide on hardwood sulphate pulp bleaching using ECF technology. The results of an experiment in assessing the performance of oxygen and hydrogen peroxide in alkali treatment are presented in relation to the conditions prevailing at the Russian plants. The scheme of hardwood pulp bleaching was as follows: D0–E (EO, EP, EOP)–D1–D2; where D – chlorine dioxide treatment, E – alkali treatment (with oxygen, with hydrogen peroxide, and with oxygen and hydrogen peroxide). Evaluation of the experimental findings allows to conclude that the oxygen utilization at the alkali stage is insufficient in pulp bleaching under a pressure of 0.2 MPa. The maximum reduction in the amount of kappa sulfate pulp and a decrease in the consumption of chlorine dioxide at the final bleaching is provided by oxidative alkaline treatment with the addition of hydrogen peroxide with a flow rate of 3.0 kg/t. For the D0–EOP–D1–D2 scheme, the addition of 1.0 kg/t of hydrogen peroxide reduces the consumption of chlorine dioxide at the stages of the final bleaching of pulp to 2.7 kg/t.

Keywords: pulp bleaching, ECF technology, sulphate hardwood pulp, oxidative alkali treatment, pulping degree, pulp brightness
Contact Interaction of a Claw Washer with Wood at Limiting Shear

Contact Interaction of a Claw Washer with Wood at Limiting Shear

Authors: E.V. Popov, A.V. Ruslanova, V.V. Sopilov, N. Zdralovic, S.M. Mamedov, B.V. Labudin
Year: 2020, Volume: 12, Number: 4
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Abstract

When designing, manufacturing and maintaining of woodworks and elements of wooden structures it is necessary to solve the problem of providing the calculation of strength, stiffness and their bearing capacity. This problem becomes particularly relevant while reconstructing and new wooden house building, as the correct choice of connection type influences the technical possibility to use wood in the elements of structures. Such types of special connectors as claw washers, gang nails, dowel connections, etc. are used for these purposes. The existing range of claw washers implies different diameters, thicknesses, and claw configurations depending on the required bearing capacity and cross-sectional dimensions of sawn timber. The accepted physical model of wood is a transtropic body. The forces transmitted in the joints of the elements of wooden structures are perceived by the total contact surface of the mating elements. However, the work of individual teeth of claw washers has been poorly studied: research on influence of geometrical characteristics of the tooth on the bearing capacity of the connector is absent; variation in thickness of the connector is not assessed. A double-sided claw washer of the Bulldog type (prototype) with the diameter of 50 mm was adopted as the object of study. Various schemes of cutting of the claw washer with predetermined dimensions (width and height) of a triangular tooth are considered. The influence of dimensions on the bearing capacity of the thickness of claw washers is estimated within 1–1.5 mm. The main criterion for the selected cutting patterns is the ability to produce the washers by single-impact stamping without additional trimming. Double-sided claw washers of 5 different types with the number of cog-teeth from 8 to 12 items on each side were studied. A differential equation of the 4th order is accepted as a mathematical model of cog-tooth action. The equation describes the behavior of a dowel on an elastic base with a fixed value of bending stiffness EI. The transition to which was carried out from the variable value EI = f(x) by searching for the equivalent width of the cross-section from the bending conditions of the element of the triangular section of a variable directed normal to the frontal surface and a constant directed normal to the lateral surface.

Keywords: wood, wooden structures, anisotropy of wood, strength, deformability, claw washers, gang nails
Obtaining Woody Greens Enriched with L-Arginine during Forestry Management of Young Scots Pine Stands (Scientific Review)

Obtaining Woody Greens Enriched with L-Arginine during Forestry Management of Young Scots Pine Stands (Scientific Review)

Authors: E.V. Robonen, N.P. Chernobrovkina, M.I. Zaitseva, B.V. Raevsky, A.V. Egorova, G.N. Kolesnikov
Year: 2020, Volume: 26, Number: 5
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Abstract

Forests produce a huge amount of organic matter, which is a source of renewable raw materials for the production of technical, feed, food and pharmaceutical products. The logging and woodworking industry in Karelia, as in Russia as a whole, is based exclusively on stem wood. Woody greens are formed while felling ripe and over-mature stands, thinning and implementation of measures for the conservation, protection and reproduction of forests including forest stands cutting. The development of technologies for the use of woody greens is necessary for the multi-purpose utilization of the entire phytomass produced by forest plant communities. An additional economic incentive for young stands thinning and limbing, that are used to improve the quality of logs, is the ability to reduce costs or even ensure the profitability of these measures driven by the development of processing plants and the use of wastes generated during transportation: thinners, low-quality and low-value decidous wood, woody greens, that are raw materials for the production of biologically active preparations of various action. The urgent tasks are to increase the use of importsubstituting pharmaceutical substances and to search the alternative methods for producing raw materials for nutrient mixtures and feed stuff. Technologies for modifying the biochemical composition of coniferous greens, resulting in production of plant raw materials enriched with target biologically active substances, are being developed for the exploration of new plant sources. The water-soluble fraction of coniferous greens contains free amino acids, in particular L-arginine, which plays an important role in the life of animals. A promising way is to increase the free amino acids content in coniferous raw materials and change their quantitative ratio by regulation of the mineral nutrition regime of woody plants. An original scheme of additional supply of coniferous plants with nitrogen and boron is proposed in order to obtain coniferous greens enriched with L-arginine. The use of conifers as bioproducers of L-arginine and the study of its metabolism with reference to climatic factors, conditions of mineral nutrition, seasonal and daily dynamics in the natural environment, the search for ways to increase its level in organs and tissues is of current interest both on the theoretical and practical sides. Obtaining coniferous greens enriched with L-arginine will allow organizing the production of coniferous products for nutrient and pharmaceutical use. It is necessary to analyze the potential sources of raw materials taking into account their availability, costs for enriching the needles with L-arginine and product yield per unit area to assess the economic feasibility of organizing such production. A developed sequence of forestry measures will make it possible to obtain needles enriched with L-arginine, both in the process of implementing various types of forest use, and in carrying out activities aimed at increasing the productivity of forests and preserving their useful functions. Herewith, it is possible to turn costly cleaning and fertilizing of young Scots pine stands into profitable ones with additional products. Technologies of intentional changes in the chemical composition and pharmacological properties of plant raw materials obtained from woody plants will allow the development of new raw materials for biologically active substances.

Keywords: forest crops, thinning, nitrogen, boron, fertilizers, Scots pine, woody greens, L-arginine, efficient use of resources
Introduction of Eucommia ulmoides Oliv. to in vitro Culture

Introduction of Eucommia ulmoides Oliv. to in vitro Culture

Authors: A.V. Zhigunov, Q.T. Nguyen
Year: 2020, Volume: 12, Number: 5
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Abstract

The increasing need for herbal medicines requires the study of not only biological resources of medical plants, but also methods for their reproduction. Of special value are the medicinal plants that have a long history of success in traditional medicine. One of such plants is Eucommia ulmoides Oliv., which belongs to a rare relict species growing in natural conditions, for the most part, in the undergrowth of humid subtropical forests in China, mainly in the middle course of the Yangtze river. E. ulmoides compares favorably with most subtropical plants owing to its significant frost resistance, which makes it possible to cultivate it outside the humid subtropics. It has been widely introduced in Krasnodar Krai and in the Republic of Adygea (Russia) since the mid-20th century and successfully adapted to various environmental conditions in the Northwest Caucasus. The increasing demand for E. ulmoides bark can only be satisfied by laying out industrial plantations. However, the difficulties encountered in the traditional seed reproduction of E. ulmoides (dioecious species, pollen low quality, parthenocarpy, prolonged seed dormancy, irregular fruiting, long juvenile period, etc.) make scientists turn to modern biotechnological methods of plant propagation. While considering cultivation of planting material, we should focus on highly efficient methods that ensure stable and mass reproduction of the plants under study. An important role is played here by in vitro plant regeneration. The effectiveness of biotechnology methods is due to a reduction in timing of obtaining a large number of vegetative progeny of plants difficult for propagation, as well saving of the area required for their cultivation. The conditions for producing an aseptic culture of E. ulmoides were chosen based on the results of the studies. The highest degree of sterilization of E. ulmoides shoot segments was achieved when the explants were sequentially immersed first in 70 % ethanol (30 s) and then in 0.1 % mercuric chloride solution (5 min). With such a sterilization procedure, 63.3 % of the studied cuttings were made sterile, and 56.7 % of them proved to be viable. The optimal composition of the nutrient medium for regeneration of E. ulmoides microshoots has been determined: MS medium complemented with 1 mg/L 6-Benzylaminopurine (BAP) + 0.2 mg/L 1-Naphthaleneacetic acid (NAA). The best media for explant rooting are the following: 2/3 MS + 1.5 mg/L NAA + 30 g sucrose + 7 g agar; 2/3 MS + 1 mg/L NAA + 0.4 mg/L IBA + 30 g sucrose + 7 g agar.

Keywords: Eucommia ulmoides Oliv., microclonal propagation, microshoot, sterilization, regeneration, growth regulator
Components of the Increment Dynamics of Early and Late Wood of Quercus robur Stem in the Upland Oak Forest of the Southern Forest-Steppе

Components of the Increment Dynamics of Early and Late Wood of Quercus robur Stem in the Upland Oak Forest of the Southern Forest-Steppе

Authors: N.F. Kaplina
Year: 2020, Volume: 7, Number: 5
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Abstract

The stem radial increment contains information on the tree growth, development, and condition. The early and late wood increment has essential features. The increment dynamics contains monotonous and cyclic components. Retrospective and predictive assessments of growth and development of a tree and a stand based on the patterns of radial increment are possible. The purpose of the article is to analyze the properties of the components and their contribution to the increment dynamics of oak early and late wood, depending on the favorability of growth period and the crown development. The research object was the artificial upland oak forest of the first quality class (pure in composition). Two periods of growth were considered: 1st – favorable (1968–1996) and 2nd – unfavourable (1997–2014). We studied three groups of oak, each group of 10 trees. The groups were distinguished by the evelopment of crown (original classification) and its dynamics. The stem cores were taken at a height of 1.3 m from the southeast side. Indicators of radial increment were defined in the images of cores scanned at 1200 dpi resolution. Three components of the dynamics were identified: a long-term trend and cyclic components with 12- and 2–5-year cycles. The variability of cyclic components of the dynamics of early wood increment was more than twice lower, than that of the late wood. The contribution of the component with 2–5-year cyclicity to the dynamics of early and late wood increment prevails during the favorable period of growth. The contribution of the component with 12-year cyclicity increases during the unfavorable period and the more, the less developed the crowns. The transition of the radial increment to a lower level occurred during the minimum of the component with 12-year cyclicity. There is no significant correlation between early and late wood increment of the component with 2–5-year cyclicity, which makes the major contribution to their ratio. The correlation between early and late wood increment of other components is closer during the unfavorable period and with a decline in crown development. The correlation between the early and late wood increment of the previous year is closer than that of the same year.

Keywords: English oak, crown development, early and late wood of stem, dynamics of radial increment, monotonous and cyclic components of dynamics
Response of Annual Ring Width and Latewood Content of Scots Pine to Weather Conditions in Provenance Trials

Response of Annual Ring Width and Latewood Content of Scots Pine to Weather Conditions in Provenance Trials

Authors: S.R. Kuzmin
Year: 2020, Volume: 16, Number: 5
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Abstract

Tree-ring width and latewood content were studied to assess the response of wood to growing conditions. Samples were taken from the trees of six Scots pine climatypes with contrast origin, grown in the conditions of provenance trials in southern taiga of Central Siberia (Boguchany forestry) and forest-steppe of Western Siberia (Suzun forestry). A comparative analysis of variance of mean values of the studied features between the climatypes within each test point and between the points is carried out. Correlation analysis was used to analyze the dynamics of the studied traits and as their response to weather conditions over a long period. It was revealed that in the forest-steppe conditions maximal radial increments for all climatypes were observed on average at the age of 9 and in southern taiga at the age of 12–16. Tree-ring width of the climatypes from the south is significantly lower in the foreststeppe conditions than that of of the representatives of northern origin. Climatypes transferred from a warmer climate to southern taiga are characterized by significantly larger values of tree-ring width than in the northernmost of the studied ones. The latewood content decreases in all studied climatypes of pine in southern taiga in comparison with foreststeppe. Significant response of the latewood content of climatypes in forest-steppe is observed not only with average monthly weather conditions of the second part of vegetation period but also with the first. It indicates a higher sensitivity of their wood structure to the complex of climatic and ecological conditions in the provenance trials of forest-steppe compared with southern taiga. The research results show that the Boguchany limatype is genetically stable in terms of the average values of tree-ring width and latewood content in foreststeppe and southern taiga.

Keywords: provenance trials, Scots pine, tree-ring width, latewood content

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