Vol 28, No 2 (2024)

The article presents the study materials of forest crops created at spot mounds in the climate conditions of the Dvinsk-Vychegodsk taiga region. We conducted a field survey of 17 forest-cultivated areas, where we laid quadrats for assessing the quality of forest crops and site preparation. We studied the water-physical properties in the rooting depth at spot mounds and cutting strips where there was no soil cultivation. It has been established that the density of forest crops generally corresponds to the regulatory limits designed in artificial reforestation projects. We have determined the survival rate of forest crops created by planting material with a root-balled and bare root tree system, which varies from 72 to 100 %. The plantations showed the highest survival rate during the first year especially pine crops with a root-balled system, in areas of two- and three-year-old crops, the survival rate is slightly lower, especially when planting bare root spruce seedlings. The results of a correlation analysis are presented, which showed that soil moisture had the greatest effect on the survival of bare root seedlings (ρ = –0,894, p = 0,04). We have analyzed the relationship between the survival rate of seedlings and the physical properties of the soil in the planting spots. We have compared the properties of the soil in the rooting depth at spot mounds and cutting strips, where no soil cultivation was carried out. It was revealed that the soil bulk density at spot mounds was 8 % higher, and humidity was 11,4 % lower. We have found that this leads to a decrease in the total porosity and an increase in the porosity of aeration in the rooting depth of the soil at spot mounds. It is shown that soil cultivation by creating spot mounds by excavators in the conditions of the North provides sufficiently favorable water-air properties of planting sites for the creation of forest crops with pine and spruce planting material with both ball-root and bare root system.

The estimation results of calorific value fractions of aerial phytomass of 76-year-old pine species in lichen, lingonberry and bilberry types forest conditions of the northern taiga region are presented. The calorific value of wood, bark, foliage, branches, dry twigs in absolutely dry state was determined with automated bomb calorimeter ABK-1V. Not any significant influence of forest type on the calorific value of pine ground phytomass fractions was established. The correlation dependence of calorific value of the following parts of pine was revealed: wood — on the average stand height, number of needles per branch, diameter of resin channel in the needles, bark — on the length and surface area of the needles, woody greenery — on the diameter of resin channels in the needles, area of the vascular bundle in the cross section of the needles, branches — from the width and proportion of late wood in the annual layer, area of the vascular bundle, central cylinder and mesophyll in the cross-section of needles, dry twigs — from the area of the vascular bundle, central cylinder in the cross-section of needles. It is recommended to use the obtained parameters of calorific value of pine aerial phytomass fractions as qualitative characteristics of planting materials.

In the western and eastern territories, P. brutia var. pityusa in the Crimean Mountains, four hypsometric profiles were used to establish trial plots. Seasonal growth of shoots was measured on trial plots near model trees. The purpose of the research was to study the biometric parameters of shoots in natural stands of P. brutia var. pityusa in the Crimean Mountains, analysis of the specifics of their seasonal growth depending on the dynamics of growing conditions. As a result of the research, it was found that the seasonal growth of shoots in plantations of P. brutia var. pityusa in the Crimean Mountains varies markedly due to the peculiarities of the orographic conditions and the moisture regime. It has been established that in the western part of the distribution of P. brutia var. pityusa, in the Ayazma tract, in years with low rainfall, the seasonal increase in shoots decreases, to the greatest extent in the plantations of the coastal zone. The prolongation of the drought effect on the growth intensity in the forest stands of the coastal zone of the Batiliman tract and in the upper belt of the Ayazma tract in the first year of the post-drought period was revealed. At present, in terms of the magnitude of seasonal growth of shoots, the most severe conditions for the growth of P. brutia var. pityusa are formed in Mount Karaul-Oba. In the western part of its distribution in the Crimean Mountains, in the Batiliman tract, an increase in the amplitude of the variability of the seasonal growth of shoots is observed due to an increase in the level of climatic factors fluctuation. It is shown that this situation reflects negative trends in the decline in the life potential of P. brutia var. pityusa city of Karaul-Oba and the natural boundary of Batiliman. It is concluded that under the conditions of global changes in the natural environment, this can enhance destructive processes in plantations of P. brutia var. pityusa within the above-mentioned areas.

The article presents the study results of Jack pine growing on the disturbed soils of the Egoryevsk pebble-phosphate field in the European part of Russia. The Jack pine is a valuable species for recultivation purposes in the conditions of the European part of Russia, in this regard, the progenity tests of this species is necessary for its further introduction. As a result of determining the germination ability of seeds, sufficiently high germinative capacity was revealed, which indicates the possibility of using them to create a regional seed base.

A conceptual model for studying the architectural and landscape environment of a pedestrian street in an urban environment is presented. A historical retrospective of Karl Marx street development in the metropolis of Voronezh is presented. The scheme of the street and road network is considered, highlighting architectural and urban planning subjects. The features of visual perception of Karl Marx street are analyzed. Modern concepts and approaches to the transformation and use of the actual landscape are presented. A diagram of the green areas of the studied city block and the most common types of plantings in the city block have been established. An assortment of plants recommended for landscaping the territory of the pedestrian Karl Marx Street in Voronezh has been determined. Indicators of the quality of landscape and recreational territory are indicated using the example of a pedestrian street. A functional zoning scheme for the block with the placement of public areas for various purposes is recommended.

The analysis results of the dendrological collection of the South Ural Botanical Garden-Institute of the Ufa Federal Research Centre of the Russian Academy of Sciences, currently numbering 1935 taxa, are presented. It includes 48 species from 33 genera and 19 families, the most species-rich families of Salicaceae and Rosaceae. It was established that 27 out of 48 species are listed by the IUCN and are under special protection in the territory of other subjects of the Russian Federation, 1 species is listed in the Red Book of Bashkortostan. Economically significant groups of woody plants of the natural flora of Bashkortostan have been identified, among which are medicinal — 46 species, wood-cellulose — 20, melliferous — 14, ornamental — 30, food — 9. All these species belong to categories I and II of the state, i.e. healthy or with slight damage to the stem. All of them are located on the Natural Forest area, in the Arboretum, partly in the collection plots, and also sporadically throughout the territory of the Botanical Garden.

Materials for studying the rheological behavior of disintegrated pine wood under uniaxial compressing are presented. The kinetics of disintegrated pine wood deformation was studied in the mode of constant speed movement of the press plunger using a rheological approach. Rheological stress-strain curves were constructed for various fractions (d < 1 mm; 1 < d < 2; 2 < d < 3; d > 5). Compression curves of compact density versus pressure were obtained. It has been shown that fractions with particle sizes less than 1 mm have the best compressibility parameters and achieve higher densities at lower pressures (ρ_заг = 1.03 g/cm³ at P = 180 MPa). Other studied fractions had approximately the same compressibility and density ρзар in the range of 0.85…0.90 g/cm³ at P = 140…160 MPa. A further increase in pressure level did not lead to an increase in density due to elastic expansion after removal of the load. The greatest strength of pressings was determined when a fraction of more than 5 mm in size. An installation and a method for assessing the strength of pressings in free settling are proposed. The results obtained can be used to optimize the process of pressing disintegrated wood and develop more efficient methods for using wood resources.

The currently existing mathematical dependencies are aimed only at substantiating the productivity of harvesters and do not allow a detailed analysis of the complexity of individual elements of the cycle time depending on natural and industrial conditions. In this regard, the purpose of this study is to substantiate the mathematical patterns of harvester operation, which allow for rapid technical calculations of productivity and labor costs with a sufficient level of reliability when performing various logging operations. To achieve this goal, a simulation model of harvester operation in a logging area was created and experiments were conducted on this model. The results of statistical processing of simulation results are shown. Regression dependencies are proposed for calculating the average hourly productivity of a harvester, as well as for calculating individual elements of its cycle time, created as a result of analyzing the results of a study on a model. The regression dependences of calculating the average time of pointing the manipulator at a growing tree, moving a fallen tree to its processing zone and the average time of moving the harvester between working positions per sawn tree, which have scientific and practical novelty, are determined. It is proved that labor rationing is impossible without taking into account the influence of such indicators on these elements of time as the average volume of whiplash in the cutting area, the proportion of the component being cut down, the forest reserve per hectare and the amount of large undergrowth in the cutting area. Diagrams of changes in the values of cycle time elements in the conditions of a variety of natural and industrial conditions in various forest areas are shown. Based on the conclusions obtained in the article, practical and scientific recommendations have been developed that increase the efficiency of labor rationing in logging operations. The obtained regression models are recommended for analyzing work efficiency and labor rationing when using the Silvatec 8266TH harvester.

The paper develops an algorithm for clustering Z-information based on reference fuzzy identification of objects belonging to clusters. The information is represented by linguistic Z-numbers, both components of which (object evaluation and their validity) are values of linguistic variables. Reference fuzzy identification of affiliation is based on information about the importance of the characteristics assessed by objects, formalized on the basis of a linguistic variable. The object evaluation and fuzzy reference identification were used to determine fuzzy rankings of the degree to which objects belong to clusters. The algorithm developed in the article improves the clustering algorithm presented by the author earlier, since it preserves more initial information due to a new approach to data formalization and reduces the fuzziness of rating objects, thereby reducing the risks of errors in decision support tasks.

Significant aspects related to the problems of forming supply chains and production volumes at forest processing enterprises are considered. The main attention is paid to the problem of assessing the optimality of decisions made. The study analyzes forestry enterprises that do not have their own sources of raw materials and seek to find the optimal solution based on information about transactions on the commodity exchange that have already been carried out. A mathematical model has been developed that takes into account the share of the useful volume of raw materials, the time spent on transportation, and uncertainties. To test the effectiveness of the model, data from the exchange and enterprises located in the Primorsky Territory were used. Thanks to this, it was possible to determine the optimal path for obtaining profit, production volume and other important indicators. The issues of planning supply chains and production volumes are discussed, the regions that source raw materials are analyzed, and the advantages and disadvantages of the proposed mathematical model are given. The results obtained can be used to carry out rational transactions on the Russian Commodity and Raw Materials Exchange and are of interest to top management of forestry enterprises that seek to improve the efficiency of their activities.