STRATIGRAPHY AND DYNAMICS OF PEAT AND CARBON ACCUMULATION ON THE RYAMS OF THE BARABA FOREST-STEPPE IN THE HOLOCENE (WEST SIBERIA)

Detailed studies of the properties and dating (13 14C dates) of peat sections of the Sherstobitovo and Ubinskoe burnt ryams were carried out. The first data on the dynamics of peat and carbon accumulation in the oligotrophic bogs of the Baraba forest-steppe of West Siberia in the Holocene were obtained. The peat deposits of these sections, respectively, are mixed multilayer forest-swamp and high moor fuscum, 2.5 and 3.47 m thick, 5254 and 6472 cal. years ago, with total reserves of absolutely dry peat – 200 and 267 kg m–2 and carbon – 91 and 124 kg C m–2. The long-term peat accumulation rates are 37.6 and 40.9 g m–2 yr–1, carbon – 17.1 and 19.0 g C m–2 yr–1, the limits of variation of peat accumulation rates in various periods of bog formation are 14.2–78.8 and 14.8–59.0 g m–2 yr–1, carbon – 6.7–32.6 and 6.8–27.5 g C m–2 yr–1. The dependence of peat accumulation dynamics on the hydrothermal climate regimes of the second half of the Holocene, the genesis and age of sections, and the local conditions of their formation is revealed. The confirmed deposition of peats on lake sapropels and organomineral deposits of reed inundated plains occurred after periods of climate aridization. Significant differences between the subsequent dynamics of peat accumulation and presence and location of primary lakes in bog massifs were revealed.