SPATIAL-TEMPORAL VARIABILITY OF SOIL MESOFAUNA BIODIVERSITY IN DIFFERENT FOREST PLOTS

Abstract

The results of the assessment of the spatial and temporal variability of the biodiversity of soil mesofauna of fresh sub-forests (type of forest vegetation conditions B2) of the southeastern part of Volyn Polissya in 2021–2025 are presented. The aim was to compare the species composition and diversity of communities in forest areas that differ like disturbances. 4 places with the same soil type were surveyed: near a highway with recreational load (No. 1), within forestry without anthropogenic impact (No. 2), in the first months after a medium-intensity fire (No. 3) and after a clear cut (No. 4). Sampling of the upper layers of soil with litter was carried out in the first decade of June; mesofauna was removed by manual analysis, sorted, counted and identified by determinants. To compare the groups, species richness S and Shannon index H’ were calculated based on relative abundance (%). During the observation period, 30 species belonging to 9 families and five classes (Oligochaeta, Arachnida, Diplopoda, Insecta, Gastropoda) were recorded. The highest values ​​of H’ and S are characteristic of site No. 1 (H’ 2.74-3.03; S 19-25), which is associated with the mosaic of microhabitats under recreational influence. Site No. 2 was relatively stable (H’ 2.43-2.64; S 14-18) and can be considered as a conditionally background variant. In site No. 3, after the fire, minimum indicators were recorded at the start (H’ 1.28-1.38; S=4) with further recovery by 2025 (H’ 2.24; S 14). At site #4, moderate values ​​were observed after logging in 2021–2024 (H’ 2.30-2.53; S 13-15) and an increase in 2025 (H’ 2.78; S 19). The results confirm the sensitivity of mesofauna to disturbances and the feasibility of using S and H’ for bioindication of forest soil condition and assessment of restoration successions. Differences in soil mesofauna characteristics can be used in monitoring forest ecosystems.