Carbon accumulation in soils of forest and bog ecosystems of southern Valdai in the Holocene

Carbon stocks and accumulation rates in humus and peat horizons of the contiguous soil series of forest and bog ecosystems have been studied in the Central Forest State Biosphere Reserve, Tver Region. Upland soil types (soddy podzolic, brown, and white podzolic) have been compared to paludified (peat-enriched gley podzolic and peaty gley) and bog soils differing in trophic status, including those of upland, transitional, and lowland bogs. The results show that carbon stocks in mineral soils are many times smaller than in waterlogged soils and an order of magnitude smaller than in bog soils. Mineral and bog soils are characterized by similar rates of carbon accumulation averaged over the entire period of their existence. The highest rate of carbon accumulation has been noted for the soils of waterlogged habitats, although this process may be periodically disturbed by fires and other stress influences.