Dynamics of Korean pine-broadleaf forest recovery after single-time logging in the 1960s in the Southern Sikhote-Alin

Relevance and aim. Korean pine-broadleaf forests of the southern Sikhote-Alin are unique ecosystems with high biological value and complex structure. Under ongoing forest exploitation and degradation of old-growth stands, the evaluation of long-term logging consequences is of special importance. This study aims to assess the state of forest stands 60–70 years after single selective logging operations conducted in the 1960s, and to compare them with preserved old-growth forests. Material and methods. The data were collected within the Verkhneussuriysky biogeocenotic station, where 346 temporary sample plots were established. For analysis, 129 plots of the K4 forest type (multi-shrub Korean pine forest with yellow birch) were selected, including both old-growth and post-logging sites. Tree diameter, height, basal area, and stem volume were measured. Calculations were performed in Python using nonparametric statistical methods. Results show that even after 60–70 years, post-logging forests still differ significantly from old-growth stands: they have lower timber stock, smaller average diameters, and lack large trees. Fast-growing pioneer deciduous species dominate, while the proportion of Korean pine is significantly reduced. These differences are statistically confirmed (Kolmogorov–Smirnov and Mann–Whitney tests). Conclusion. Thus, the restoration of the original structure of Korean pine-broadleaf forests is extremely slow and remains incomplete even decades after logging. This highlights the need to reconsider forestry practices aimed at conserving and restoring these ecosystems.