Аннотация
Studying the causes of forest dieback in Norway spruce (Pícea ábies) and Scots pine (Pinus sylvestris) stands is crucial for predicting their occurrence, promoting sustainable forest management and reforestation, and investigating the properties of forest products derived from fallen wood. This research presents structured data on identified forest dieback hotspots in various regions, establishing that spruce dieback is a part of the overall boreal forest dieback currently observed in Russia, Europe, and North America. A structured review of the main factors influencing the drying out of forest stands showed that the first group includes biotic causes (infection of forest stands by root rot, bacteria, etc.), and the second group includes abiotic causes (waterlogging, swamping, poor soils, windfall, forestry activities, fires, consequences of land reclamation, recreational load). One of the main biotic causes of tree wilting is bacterial infection. Bacteriosis, as the primary agent, manifests itself as a concurrent infection with diseases such as various types of root fungus, Dutch elm disease, and oak tracheomycosis. Bacterial growth is driven by climate change and a number of abiotic factors specific to a given region. Active use of data and predictive modeling based on soil, climate, fire and logging history, species composition, and remote sensing data allows for forecasting the distribution and intensity of key types of decay (especially rot) at the forest stand level, enabling informed planning of management activities and optimization of logistics for the active processing of fallen timber. Monitoring dangerous pathogens and regulating the volume of deadwood to economically and environmentally acceptable levels represents a shift from fighting to managing decay. Sustainable forestry recognizes the environmental value of fallen timber as a component of deadwood and a raw material in the production of advanced chemical processing products based on responsible biorefining, particularly cellulose for various purposes and fuel pellets.