Additional files [RJEE Vol. 7 (1). 2022 – 5]

• Fig. 1. The study area in (A) Eurasia and (B) within the Ural montane forests and tundra ecoregion. Legend: – Visim NBR, II – Pechora-Ilych NBR; 1 – Intact Forest Landscapes [39, updated in 2018]; 2–7 – Terrestrial Ecoregions [40]: 2 – Scandinavian and Russian taiga, 3 – West Siberian taiga, 4 – Sarmatic mixed forest, 5 – Western Siberian hemiboreal forests, 6 – East European forest steppe, 7 – Ural montane forests and tundra; 8–9 – geographic provinces in the Urals [41]: 8 – the North Urals, 9 – the Middle Urals; 10 – areas of state nature reserves
• Fig. 2. Physiognomy of the studied communities in the Visim NBR: (A) the primary fir-spruce forest (PrFS); (B) the post-fire birch forest (PfB). Photo by R. Sibgatullin
• Fig. 3. Physiognomy of the studied communities in the Pechora–Ilych NBR: (A) the primary fir-spruce forest (PrFS); (B) the post-fire birch forest (PfB). Photo by A. Aleinikov
• Fig. 4. Parameters of structure and vascular plant diversity in the primary fir – spruce (PrFS) and the post fire birch (PfB) forests in the Visim NBR. A–D – the cover of vegetation layers: A – trees, B – tree understorey and shrub undergrowth, C – herbs, D – mosses. E–O – number of species: E – total for vascular plants, F – all trees, G – all shrubs, H – all herbs; I–O – in the considered functional species groups (all life forms together): I – forest boreal, J – forest-edge boreal, K – forest nemoral, L – forest-edge nemoral, M – forest nitrophilous, N – forest-edge nitrophilous, O – meadow. Symbols represent the vegetation relevés by variants of sub-coenosis parcelles: 1 – fir–spruce, 2 – spruce-deciduous, 3 – gap with abundant tree understorey and shrub undergrowth, 4 – opened gap with little tree understorey and shrub undergrowth. For the compared relevé samples, significant differences (Mann – Whitney test, p < 0.05) are indicated by arrows: ↑  –  higher values, ↓  –  lower values
• Fig. 5. Parameters of structure and vascular plant diversity in the primary fir – spruce (PrFS) and the post fire birch (PfB) forests in the Pechora – Ilych NBR. A–D – the cover of vegetation layers: A – trees, B – tree understorey and shrub undergrowth, C – herbs, D – mosses. E–O – number of species: E – total for vascular plants, F – all trees, G – all shrubs, H – all herbs; I–O – in the considered functional species groups (all life forms together): I – forest boreal, J – forest-edge boreal, K – forest nemoral, L – forest-edge nemoral, M – forest nitrophilous, N – forest-edge nitrophilous, O – meadow. Symbols represent relevés from the (1) PrFS and (2) PfB. For the compared relevé samples, significant differences (Mann – Whitney test, p < 0.05) are indicated by arrows: ↑  –  higher values, ↓  –  lower values
• Fig. 6. Demographic structure of tree species populations in the studied forests of the Visim NBR. The ontogeny spectra by the studied communities: A–C – the primary fir–spruce (PrFS) forest, D–I – the post fire birch (PfB) forest. The ontogeny spectra by tree species: A, D – fir (Abies sibirica); B, E – birch species (Betula pendula + B. pubescens); C, F – spruce (Picea obovata); G – Scots pine (Pinus sylvestris); H – aspen (Populus tremula); I – goat willow (Salix caprea). Explanations of the ontogeny stages see in the text section “Study of demographic structure in tree populations”
• Fig. 7. Demographic structure of tree species populations in the studied forests of the Pechora–Ilych NBR. The ontogeny spectra by the studied communities: A–D – the primary fir-spruce (PrFS) forest, E–G – the post fire birch (PfB) forest. The ontogeny spectra by tree species: A, E – fir (Abies sibirica); B, F – pubescent birch (Betula pubescens); C, G – spruce (Picea obovata); D – Siberian pine (Pinus sibirica). Explanations of the ontogeny stages see in the section “Study of demographic structure in tree populations”
• Fig. 8. The soil invertebrate numbers (ind. per 1 m², annual average values) in the primary fir–spruce (PrFS) and the post fire birch (PfB) forests in the Visim NBR. А – total, В – saprophages, С – earthworms
• Fig. 9. Taxonomic (А) and morpho-ecological (B) structure of earthworm fauna (the shares of the total population numbers) in the studied forests of the Visim NBR. Decoded abbreviations see in Fig. 8 and in the text section “Study objects”