This article examines the specifics of strategic planning in forestry in the Russian Federation at the regional level. The aim of the study is to analyze forest plans in the constituent entities of the Northwestern Federal District and identify differences in their structure, performance indicator system, and strategic priorities for forestry development. The methodological basis for the study is a comparative and content analysis of forestry plan texts from eleven constituent entities of the Northwestern Federal District. The study revealed that the connection between regional forestry plans and the federal forestry development strategy is, in many cases, primarily formal. Differences in regional strategic priorities, performance indicator system, and the role of forestry plans in forestry management are identified. A typology of regional forestry plans is provided based on their integration with federal forestry policy and forestry planning models. The results of the study demonstrate that, despite a formally uniform document structure, regional plans form a heterogeneous system of strategic forestry management. A conclusion was made on the need to improve methodological approaches to the development of forest plans for the constituent entities of the Russian Federation and to increase the degree of their consistency with federal strategic documents, which is an important condition for the formation of the National Forest Plan of the Russian Federation.
Increasing labour productivity in mechanised logging is constrained by environmental damage from heavy machinery: specific ground pressure reaches 0.08–0.12 MPa, rut depth – 20–30 cm, root system damage to remaining trees – up to 60–70%. Reducing the negative impact is possible by using general-purpose tractors with mounted attachments. Based on the analysis of existing devices (LTN 50 skidding winches, ZT 140 M grapple grabs, UTU 2 “PAUK M”, HRZ and Uniforest grapples), it was found that the most effective is a mounted skidding trolley with a grapple operating in semi-suspended mode. The authors propose two patented design variants [24]. Key parameters: load capacity up to 5 t (bunch volume up to 6 solid m³), trolley weight 380 kg, clamping force of jaws at least 35 kN, hydraulic system working pressure 16–20 MPa, grab/release cycle time 5–8 s. Attachment to a tractor (e.g., MTZ-320) is via a category 2 three-point hitch (GOST 3480–76). During the working stroke, the trolley rolls on 6.50–10 pneumatic tyres, relieving the tractor’s rear axle by 35–40%, reducing traction resistance by 25–30% and specific ground pressure to 0.02–0.03 MPa (3–4 times lower than with choker skidding), and rut depth to 5–8 cm. During idle travel, the trolley is raised to a clearance of at least 400 mm, increasing tractor manoeuvrability (turning radius reduced by 20–25%) and reducing chassis wear. Traction calculation for the MTZ-320 tractor (power 26.48 kW, η=0.85) showed a tangential traction force of 16.55 kN, permissible bunch weight of 30.8 kN, bunch volume of 2.8–3.9 m³ depending on log length (4.5 m). Shift productivity at a skidding distance of 100 m and a log volume of 0.38 m³ is 97.7–104.8 m³/shift depending on the speed mode (idle speed 1.81–2.49 m/s, loaded speed 1.02–1.36 m/s). The developed 3D models and kinematic schemes confirm the trolley’s adaptation to terrain irregularities (angular movements up to ±15°) and high maintainability in field conditions.
Abstract The article presents the results of a study aimed at substantiating the working height of a brush cutter rotor. To describe the branch response, a model based on the Euler–Bernoulli equations with the projection of the impulse force onto modal forms was used, which describes the energy distribution and maximum displacements depending on the impulse, impact duration, branch geometry, and the point of application x_0. Analytical expressions for natural frequencies and vibration modes, formulas for calculating the modal energy and the dependence of the oscillation energy and branch deviation on the impact impulse and the height of its application to the branch were obtained. These formulas make it possible to relate the rotor parameters - rotation frequency, mass, blade distance from the rotor axis - with the expected oscillations and branch fracture. For a branch 1.5 m long and 0.01 m in diameter, the obtained natural frequencies of the first five vibration modes were 2.91; 17.34; 48.25; 94.51 and 156.17 Hz. To verify the modal analysis, a frequency analysis was performed in CAD; the deviation of natural frequencies for the first five modes is less than 1%. A model of the rotor hydraulic drive was developed, taking into account its inertial parameters and pressure changes in the pressure hydraulic line. It was found that when cutting branches with a diameter of 10…30 mm, the energy from the flywheel inertia is primarily consumed, which is restored by the drive between blows. The obtained theoretical values during branch cutting are compared with the results of experimental studies on a prototype brushcutter rotor. It was found that the hydraulic drive model satisfactorily describes the pressure changes in the hydraulic system. The most rational cutting height is shown to be 0.2…0.4 m. The obtained results can be used in the design of brushcutters and the selection of the parameters of their working tools. Limitations of the model: linearization, the need for calibration of parameters for different wood species.
The object of the study is industrial forest plantations of pine aged 6-12 years, created on freshly cleared land in the berry pine forest type of the Middle Urals. The aim of the study is to assess the dynamics of changes in the structure and biometric indicators and parameters of tree crowns in industrial forest plantations of Scots pine. The research was conducted in 2018-2024 on a permanent test plot. During field studies, the number of surviving trees was determined: 66.5% of the total number of planted trees survived in 6-year-old crops, 60.0% in 9-year-old crops, and 55.4% in 12-year-old crops. For all surviving trees in the permanent trial plot, the diameter at mid-trunk height, trunk height, crown dimensions along and across the row were measured, and the length of all annual shoots was also measured. The data obtained during field studies, in laboratory conditions, were processed using mathematical statistics methods. A dynamic increase over time in the average taxation parameters of trees and their crowns, a certain decrease in the value of the variation coefficient and the amplitude of rank coefficients were established. Relative stabilization of the structure along the trunk thickness is observed only in 12-year-old pine crops. The structure of the trunk height significantly stabilizes by the age of 12 years of forest plantations, and the leaders and the most lagging trees in height are finally determined. The coefficient of determination between the height of trees and their trunk thickness significantly decreases from 0.653 to 0.428 with increasing age of pine forest plantations. The multiple correlation coefficient between tree height, tree trunk thickness and crown projection area steadily decreases from 0.897 to 0.522 with increasing age of pine forest plantations.
