Regeneration of Dark Coniferous Species in the Groups of Picea orientalis (Pinaceae) Drying in the Teberda Nature Reserve (Western Caucasus).

The paper presents the results of a survey of the groups of oriental spruce (Picea orientalis (L.) Link.) decline in the Teberda State Natural Biosphere Reserve, Western Caucasus. Mass drying of the spruce from the European spruce bark beetle (Ips typographus) was noted both in monodominant spruce forests and in mixed stands with Abies nordmanniana (Stev.) Spach and Fagus orientalis Lipsky. Dark coniferous species currently predominate among the regrowth in the sites of spruce drying, and the participation of deciduous trees is minor. Broadleaf species are present in small numbers in the second layer in a half of the sample plots and do not have a noticeable effect on the abundance of coniferous regeneration. The fir regeneration is more uniform and stable as compared to the spruce. In most of the sample plots, the numbers of fir regrowth naturally decrease with maturing, while spruce has "bursts" of regeneration. The height and radial growth of the fir and spruce regrowth, as well as their density and distribution over the area, are discussed. It is shown that in 7 years after the beginning of the mass spruce drying in the Teberda Nature Reserve, no more than 1/5 of the area of the drying groups is provided with a reliable regrowth of dark coniferous species. In the coming years, the regeneration of dark coniferous species will be replenished only by the fir, since there are scarcely any remaining generative spruce trees. In the future, provided that fires are prevented, part of the large spruce regrowth can become a source of spruce renewal, and the fallen dead wood can become a suitable substrate for young trees.