The State and Biochemical Composition of Coniferous Plant Wood in Places of Degradation

Abstract Background. A significant deterioration in the state of dark coniferous forests, which in some cases is accompanied by their drying, has manifested itself throughout the Northern Hemisphere. This process is very dynamic and covers the entire boreal zone from Europe to the North American continent, covering all forest-forming species Research in the field of the ecological biochemistry of wood opens up wide possibilities for studying the stability of spruce stands. Coniferous wood, including spruce, consists of polymer structural components (cellulose, hemicellulose and lignin) and non-structural components (including extractives, ash and other minor substances). Extractives with high biological activity, which are produced as protective compounds during the life of plants from external environmental stresses, play an important protective function in coniferous wood. The structure of wood and its biochemical composition can change under various influences. The content of extractives varies greatly not only in different areas, but also from specimen to specimen, depending on their condition. In this regard, the aim of our research was to study the content of extractives in spruce wood in specimens of different life states.Methods. This work presents the results of studies on the characteristics of the biochemical composition of Siberian spruce (Pícea obovata L.) in mass drying conditions in the territory of the Udmurt Republic (Russia). The enumeration method was used to create a plot taxation. A study of the biochemical composition of wood was carried out based on the content of extractives from specimens in various life states. Results. Trial plot stands are characterized by low tree density in the main canopy. According to biochemical analysis, the highest content of extractives was observed in specimens with good and satisfactory vitality. In trees with an unsatisfactory life state, biochemical parameters were low, which is associated with the lack of self-regulation in dead wood. Conclusions. Obviously, the substances under study play a large role in the adaptive reactions of Pícea obovata, and the increase in their production is a response to negative environmental factors.