HIGH-RESOLUTION GIS-BASED INVENTORY OF THE WEST SIBERIAN PEAT CARBON POOL

Peatlands in the West Siberian Lowland (WSL) store a significant fraction of the global terrestrial carbon pool in the form of peat. However, the areal extent and total carbon pool of WSL peatlands have not been investigated in spatial detail. Here, a high-resolution, GIS-based inventory of WSL peatlands is used to provide a refined estimate of total carbon storage. Assimilated data sources include (1) an archive of printed data reports based on ~40 years of field surveys conducted since the 1950’s by Geoltorfrazvedka, Moscow, as well as recent updates from the 1990’s. These reports consist of detailed maps with associated field and laboratory measurements of peatland depth, area, bulk density, and ash content for 9,691 peatlands throughout the WSL; (2) our own field data from 1999, 2000 and 2001, including peat physical properties from 87 cores, 78 additional measurements of peatland depth, and sixteen ground-penetrating radar transects; (3) A Russian wetland map (Romanova et al., 1977) extending coverage beyond that of the Geoltorfrazvedka reports; (4) Visible/near-infrared MSU-SK satellite images from the Russian RESURS-01 satellite; and (5) 62 additional depth measurements gleaned from the published literature.

Our inventory finds that the WSL peat carbon pool is substantially larger than previously thought, yielding a new WSL peat carbon pool estimate of 70.2 Pg C. This value is highly conservative because like previous investigators we do not consider thin peats (<50 cm) in our inventory, and we conservatively assume 52% peat organic carbon content. However, even at 70.2 Pg C the WSL represents a substantial Holocene carbon sink, averaging 6.1 Tg C yr-1 over the past ~11.5 ka and 7 – 26% of all terrestrial carbon accumulated since the Last Glacial Maximum.