This study investigated the effect of applying the “Rotstop” preparation, which contains the competitive fungus Phlebiopsis gigantea (Fr.) Jülich, during the partial reconstruction of Scots pine monocultures threatened by Heterobasidion annosum (Fr.) Bref. root rot, on ground beetle (Carabidae) assemblages. The research was carried out in seven forest districts across Poland, in 22−to 28−year−old pine stands on post−agricultural land. Carabidae were collected using pitfall traps and “photoeclector” traps in artificial gaps treated with “Rotstop”, natural gaps, and the surrounding forest stand. The results showed that the application of “Rotstop” increased the species richness of Carabidae assemblages and improved their living conditions in the artificial gaps compared to the natural gaps and untreated forest stand. The artificial gaps significantly enhanced conditions for Carabidae colonising stumps due to accelerated wood decomposition and better access between fragments used as shelters or overwintering sites. These features were not observed in natural gaps. The Carabidae assemblages in the reconstructed stands were characterised by diverse trophic structures and habitat preferences, reflecting their high adaptability to changing environmental conditions. The results indicate that the application of “Rotstop” in the “artificial gap” method is an effective prophylactic and therapeutic treatment that not only limits the development of root rot but also supports the reconstruction of pine monocultures on post−agricultural land towards more resistant and biodiverse systems. By improving habitat conditions for Carabidae, this treatment contributes to the stabilisation and strengthening of biodiversity, which is crucial for forest sustainability in the face of climate change and increasing pathogen pressures.
Grzegorz Tarwacki (Thu,) studied this question.