Abstract

The study presents an analysis of aging (falling) organs (leaves/needle-foliage) of Siberian spruce (Picea abies ssp. obovata (Ledeb.) Domin), downy birch (Betula pubescens Ehrh), lingonberry (Vaccinium vitis-idaea L.), mountain crowberry (Empetrum hermaphroditum Hager.), European blueberry (Vaccinium myrtillus L.), Schreber’s big red stem moss (Pleurozium schreberi (Brid.) Mitt.), Polytrichum spp., dwarf cornel (Chamaepericlymenum suecicum (L.) Aschers. & Graebn. (Cornus suecica L.)), and wavy hair-grass (Deschampsia flexuosa (L.) Trin.). We found a significant variation in the chemical composition (the content of lignin, phenolic compounds, tannins, nitrogen, and carbon, as well as the stoichiometric ratios “C/N,” “lignin/N,” “lignin/cellulose”) in different plant species of northern taiga forests. The supply of secondary metabolites with litter depended on the species composition of plant communities and the contribution of different plant species to the composition of the vegetation cover. The content of soluble tannins increased (p < 0.05) in spruce needle-foliage in an automorphic position in the landscape for Siberian spruce growing in different positions of the landscape of dwarf shrub-green moss spruce forests (automorphic, transit and accumulative landscapes), so intra-specific differences were found. Relationships between secondary metabolites, nitrogen and carbon have been studied in the aging photosynthetic organs of dominant various plant species in northern taiga spruce shrub-green moss forests.