Zakalyukina Yulia Vladimirovna

Yu. V. Zakalyukina, A. R. Zaytsev, A. A. Belov, Yu. A. Zavgorodnyaya, M. V. Golichenkov The study assessed the impact of the nest-building activity of Camponotusvagus ants on the biological activity of microbial communities in the nest material compared to the surrounding soil. The objects of the study were samples from the aboveground and underground parts of theblack carpenter’s nest, built in a dead wood of Pinus sylvestris L., collected in the Ryazan region in a pine forest on humic arenosols. Using optical and scanning electron microscopy, a specific "nest material" was characterized, consisting of wood, plant debris and sand, densely woven with fungal mycelium, in which the presence of actinomycetes and unicellular bacteria forming associations was also shown. Comparative analysis of the elemental composition (C, N, P, S) demonstrated that this woody material is significantly enriched in all biophilic nutrients, and the C:N ratio in the nest material is effectively reduced compared to dead pine wood. The microbial community of the "nest material" was characterized by an increased intensity of processes involved in the nitrogen and carbon cycles (potential activity of nitrogen fixation, denitrification, CO₂ emission, and CH₄ production) compared to the microbial communities of the soil part of the nest and the control soil. Thus, during their nest-building activity in pine forests formed on poor sandy soils, Camponotusvagus ants intensify wood decomposition and thereby create unique habitats ("hotspots") with elevated biological activity. This underscores the important ecosystem function of carpenter ants. There are grounds to suggest possible symbiotic relationships between the ants and the mycelial microorganisms that form the so-called "nest material".