Comprehensive Assessment of the Influence of Hydroforestry Reclamation and Silvicultural Measures on the Productivity of Scots Pine (Pinus Sylvestris L.) under the Conditions of the Vologda Region

The relevance of the study is determined by the need for a comprehensive assessment of the long-term impact of hydroforestry reclamation and silvicultural treatments on the productivity and wood quality of pine forests in the context of large-scale climatic changes. Aim of the Work. The aim of the work is to analyze the dynamics of forest inventory parameters, resin productivity, and macrostructure of Scots pine (Pinus sylvestris L.) wood at long-term monitoring sites in the Sokolsky Municipal District of the Vologda Region. Methods. The research was conducted on nine sample plots established in different site conditions: natural swamp forest stands (control), drainage (1970s), and drainage combined with silvicultural measures (intermediate thinning and selective logging; 1990s). Standard forest inventory methods, resin productivity assessment (according to OST 13-80-79), dendrochronological analysis, and calculation of basic wood density were applied. It was found that hydroforestry reclamation had a positive effect on timber stock (an increase of 30–35% compared to the waterlogged control). The implemented silvicultural treatments optimized the stand structure, increasing the proportion of trees in the higher Kraft classes. It was revealed that maximum resin productivity is characteristic of drained stands that underwent intermediate thinning (239 g), as well as natural lowland bogs. Furthermore, wide-crowned trees produced significantly more oleoresin during tapping compared to narrow-crowned trees. A relationship was found between turpentine yield and crown exposure, attributed to the orientation of drainage ditches. Dendrochronological analysis showed that drainage stimulates wood growth: tree-ring width increased by 9% due to the thickening of the latewood zone (by 27%) while earlywood decreased (by 15%). The wood density of pine in near-ditch areas of reclaimed forest strips increased by 5%, exceeding the regional average.