Carbon accumulation dynamics of the Klukva peatland at the southern boundary of broad-leaved forest zone in European Russia

Abstract

The study is focused on reconstructing the carbon accumulation rate of the peatland Klukva (1 ha) situated at the southern boundary of broad-leaved forest zone within the Oka river basin in European Russia. The age of the peatland is about 9400 cal years BP and it is one of the oldest peatlands within the Central Russian Upland. The results of our experimental study showed that the rate of peat accumulation is ranged from 0.15 to 0.9 mm/year and it was strongly influenced by climatic factors. Two main stages were distinguished in the peatland genesis. The longest was the mesotrophic stage, which began in the Early Holocene at about 9400 cal years BP and ended in the Late Holocene at about 1500 cal years BP. Since 1500 cal years BP there has been a gradual transition of the peatland from mesotrophic to oligotrophic type. The mean carbon accumulation rate during the peatland Klukva development was about 20 gC/(m2yr). This process was most actively going between 2500 and 6300 cal yrs BP, when the rates of peat accumulation increased to 26-29 gC/(m2yr). Nowadays, the carbon stock in the peat deposit of the peatland Klukva is amounted to 175 kgC/m2 and it is comparable with the carbon stocks of boreal peatlands in Northern Eurasia. This means that the oligotrophic peatlands situated at the southern boundary of broad-leaved forest zone, despite the small areas, continue to be a large stock of atmospheric carbon.