Forest Stand Changes Drive Conservation of Understory Composition and Biomass in the Boreal Forest of the Southern Urals

The health of ecosystems, their functionality and the fulfilment of ecosystem functions are all dependent on biodiversity and productivity. The ongoing transformation of forests is intensifying the need for conservation. At the same time, the herbaceous layer has not yet been studied enough by researchers. The aim of the study is to ascertain the impact of the composition and age of the stand of primary and secondary forests on the biomass and species diversity of the herbaceous layer in the most prevalent forest type of the Western Macroscline of the Southern Urals: moss spruce forests. The methodological basis was chosen to be genetic forest typology and generally accepted methods of studying forest vegetation. We studied primary dark coniferous forests, as well as secondary birch and aspen forests of different compositions and ages. Positive correlations with the age of the stand were found to be most pronounced for Oxalis acetosella L. and Lycopodium clavatum L., while negative correlations were found to be most pronounced for Deschampsia caespitosa (L.) P. Beauv., Brachypodium pinnatum (L.) Beauv., and Dactylis glomerata L. The positive correlations with the proportion of birch and aspen in the stand composition are most pronounced for Dactylis glomerata L., Geum rivale L., Aegopodium podagraria L., Aconitum septentrionale Koelle, and Prunella vulgaris L. The research results clearly demonstrate the length of time that changes in species composition and productivity of the herbaceous layer of mountain forests take place over. This must be considered when planning forest management and nature conservation in mountain forests in the Urals. On the one hand, our study is certainly regional, but on the other, similar forests, forest degradation, regenerative succession and the plant species studied are widespread in the boreal zone. Therefore, the research results will be of interest to many researchers whose work relates to forest resources, biodiversity conservation and forest succession. To expand the scope of the research, further studies are planned in other types of forest in the Ural Mountains.