CHANGES IN CARBON POOLS OF PEATLAND AND FORESTS IN NORTHWESTERN RUSSIA DURING THE HOLOCENE

Estimates of changes in carbon pools of vegetation and soils during th e Holocene are contradictory due in part to incomplete information. Th e peat carbon pool has increased in northwestern Russia due to paludif ication but the intensity of paludification and carbon accumulation ra te was not constant during the Holocene. We estimate that the average long-term accumulation rate in peatlands of Russia was 44.10(9) kg C/y r or 28.6.10(-3) kg C/m(2) yr. According to our model calculations, th e maximum rate of pear accumulation in northwestern Russia was reached in the Boreal (early Holocene) (34.5.10(-3) kg C/m(2) yr) and the lat e Atlantic time (mid Holocene) (about 30.10(-3) kg C/m(2) yr). The rat e decreased during the Subboreal time to 17.10(-3) kg C/m(2) yr. Moder n rates of carbon accumulation in some types of peatlands of Russia, c alculated by peat-growth model, range from 20.10(-3) kg C/m(2) yr to 1 00.10(-3) kg C/m(2) yr. The forest composition of northwestern Russia also changed during the Holocene, but the changes in carbon pool of ph ytomass did not exceed 5% from the mid-Holocene to the present. (C) 19 98 Elsevier Science B.V. All rights reserved.