Nutrient Cycle in Indigenous Polytric–Sphagnum Spruce Forests of the Komi Republic

This paper presents materials that show the local cycle of chemical elements in the soil–phytocenosis system of a mature middle taiga polytric–sphagnum spruce forest on hydromorphic podzolic soils. The structure of organic and mineral matter of plants of different tiers is also presented here. The work also provides a concept for the nitrogen and ash elements migration in the process of phytomass forming and their influx with plant litter. The main role in the structural composition of annual production of organic matter and litter in the ecosystem of an old-growth spruce forest is played by the forest stand. It is established that 1329.84 kg ha–1 of mineral nutrition elements accumulate in plant phytomass. N, Ca, and K are characterized by a greater accumulation capacity. Spruce forest plants remove 136.18 kg ha–1 of mineral nutrition elements from soils with annual production. With annual litter, 107.00 kg ha–1 of nitrogen and ash elements return to the soil, of which 37.0 kg ha–1 are released in the process of plant litter decomposition. The organic soil horizon is the main accumulator of nutrients, where 2421.79 kg ha–1 of chemical elements are concentrated. With atmospheric precipitation, 22.6 kg ha–1 of nitrogen and ash elements enter the soil during the year. It is shown that the rate of mineral elements leaching with surface waters beyond the root layer (0–40 cm) is 71.78 kg ha–1 per year.