A comparative assessment of pH, concentrations and fluxes of dissolved organic carbon and total nitrogen was carried out in three types of biogeocenoses: poaceae birch forest, tall herbs alder-willow birch forest and a forb-poaceae meadow. The plots are located on an abandoned arable land in the Cherepovets district of the Vologda Oblast; the soil type is sod-podzolic postagrogenic residual-calcareous. The influx of dissolved organic carbon in forest biogeocenoses is 4.2 times greater than in meadow biogeocenoses; the deflux in forest ecosystems is 3.6 times lower compared to meadow. The influx of dissolved total nitrogen does not differ in the studied biogeocenoses, while the deflux in meadow biogeocenoses is 5.4 times greater compared to forest ones. Carbon accumulation in the soil profile of forest biogeocenoses averages 48.5 kg C/(ha year), while for meadow biogeocenoses the balance between the influx with atmospheric deposition and the deflux with soil water is close to neutral (-1.7 kg C/(ha year)). Nitrogen accumulation rate in forest ecosystems is 1.5–1.7 kg N/(ha year), but only 1.0 kg N/(ha year) in the meadow biogeocenoses. It has been shown that the formation of woody vegetation on abandoned arable land has a significant effect on the fluxes of dissolved organic carbon and nitrogen, both during the passing of organic matter through the tree canopy and the soil profile.
D.V. Gichan (Wed,) studied this question.